Monthly Archives: November 2015

#18 USMC Sherman Use: The Sherman Became A Key Part In Victory In The Pacific.

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Shermans used by the United States Marine Corps:  “The enemy’s power lies in his tanks.” – Lieutenant General Mitsuru Ushijima, Okinawa.

Most people have the idea the Marines used the Sherman tank extensively during the war. Through most of the war, they used the M4A2, but the A1 and A3 saw use as well.   The reason they got more A2 tanks, was that’s what was available when they asked, there wasn’t much choice involved, and they should feel lucky the army didn’t dump M3 Lee’s on them. The Marines also used M4A1s in one campaign, and M4A3 from Iwo Jima on in increasing numbers, all with the 75mm gun.

By the end of the war, the Marines would be experts in employing the Tank, Infantry, team. The Marines, like their European Army counterparts, used, Yankee ingenuity to modify their Shermans to help them survive combat their designers had no idea they would see. These modifications included improvised waterproofing and deep wading kits. They also included improvised add-on armor made of wood and concrete, and the use of spikes and screens over the hatches to help prevent the Japanese from using explosives directly on the periscope ports and hatches.

The Marines had toyed around with tanks in the 20 and 30s but never had the budget to buy many. The ones they did buy were all light tanks that wouldn’t see combat use. The first tank they would use in combat in WWII was the M3 light, using it on in all major campaigns until 1943 when the Sherman entered the scene. The first combat for the Sherman would be Tarawa, where they used a battalion of tanks that were mixed, two companies of lights, and one of the mediums. After Tarawa, the use of lights would not be fully suspended, but the Sherman would be the tank of choice for the rest of the war and lights would be phased out.

The Marines ultimately ended up with six tank battalions and a training school at Camp Eliot California. The first two battalions formed were the 1st and 2nd and deployed without training at the tank school, and a lot of rejects from other units. After the first two battalions formed, most of the Marines’ tankers went through the school, and the school trained almost all the new NCOs and officers.  When the war ended, all but the 1st and 2nd were disbanded, and the 1st and 2nd have remained active since the beginning, and are still in operation today.

When the fighting was over on Okinawa, Major-General Lemuel Shepard, the Marine ground commander had this to say: “If anyone supporting arm can be singled out as having contributed more than any others during the progress of the campaign, the tank would certainly be selected.”

The Sherman would go on serving the Marines in Korea, though by then it was just the M4A3 105 tanks and Sherman based recovery vehicles.

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#17 The WWII Medium Tank Battalion: The Heart Of An Armored Division, Or The Heavy Gun Support To An Infantry Division

The US Army Tank Battalion:  How Sherman tanks were deployed

There were two types of  tank battalion, the type attached to infantry divisions, as ‘independent’ tank battalions,  and the type that were a part of an armored division. They were pretty much the same in organization, if not in how they were used. The life of a tanker could vary wildly from another’s depending on where he got assigned, and the tamest would probably be when they got sent to an armored division.

The Tank Battalion at the start of the war was composed of a much smaller number of vehicles and almost no specialized ones.  As the war progressed, the Tank Battalion filled out a lot. They even added a whole service company with a large number of trucks, wreckers, and ARVs. Early in the war, they seem to have relied on the M3half track to fill in for specialty vehicles they didn’t know they needed yet. Once they figured it out in 1943 though, the tank battalion doesn’t seem to have changed much

The Tank Platoon:  The Smallest Official Tank Unit

Let’s start with the smallest subunit of the Tank Battalion, The tank platoon.

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A Lee tank platoon in North Africa or training in the US would have (1) Officer, (9) NCOs, and (25) enlisted men. Later this would be reduced by five enlisted as the radio operator was dropped. In the US the tanks could be several kinds of Lee, but the units that deployed with M3 Lee tanks for Torch were M3 Lee models with the R975 powering it.  The Lee was pretty short-lived in US Service, and the US only took them into combat because there was a shortage of Shermans because of British needs, but once supplies were up, the US removed them, even from training. Many got shipped to the Australians.

A Sherman platoon would be made up of five Sherman tanks, Early in the war, M4s and M4A1 75 tanks, by late 44, they might be a mix of M4 75s, M4A1 75s, M4A3 75w tanks, and M4A1 and M4A3 76 tanks, though some units kept all 75mm tanks. The likely mix would be some M4A3 75 tanks, and M4A3 76 tanks, with some M4A1 76s mixed in with some small hatch M4s and M4A3s. The optimal number of men for a tank platoon is 25, (1) Officer, (9) NCOs, and (15) regular GIs.

These men would be permanently assigned to one of the tanks. In most cases, the tanks were named, and the name reflected the platoons, company designation, for this example we’ll say the platoon belongs to B Company, so all five tanks will be named something starting in B. In the field, the tank would be home, and they would sleep under its tarp next to it, or in it if they were paranoid.  The men of a tank platoon would be very close, as they would spend a lot of time with each other.

No. 1 Brenda: M4A3 76w, Platoon leader, Commander by a Lieutenant, Gunner: Corporal, Loader, Driver, and Co-Driver: Jr enlisted.  The tank has commander’s radios.

No. 2 Bonnie: M4A3 75w, Commander by a Sargent Gunner: Corporal, Loader, Driver, and Co-Driver: Jr enlisted. Nice new large hatch tank

No. 3 Battlingbitch: M4A1 76w, Commander by a Sargent Gunner: Corporal, Loader, Driver, and Co-Driver: Jr enlisted. This tank has been around since Cobra.

No. 4 Bronco: M4A3 75, Commander by a Staff Sargent Gunner: Corporal, Loader, Driver, and Co-Driver: Jr enlisted.  Another small hatch survivor has all updates and C/O radio.

No. 5 BettyW: M4A1 75, Commander by a sergeant, Gunner: Corporal, Loader, Driver, and Co-Driver: Jr enlisted.  This tank is a small hatch survivor.

This was as small as the unit was broken down in an Armored Division, at least most of the time. In a separate tank battalion, things would be different. Often a battalion would be assigned to an infantry division for an extended period of time, a few of the divisions the entire war, and they used tanks differently. Sometimes assigning two tanks to a company of infantry, or three.  Two tanks were called a Light Section, three a Heavy Section, and that was as small as the tankers wanted to go, but sometimes even single tanks could be working with a couple of platoons of infantry more than their partner tank.

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A Platoon of M4A3 76W HVSS tanks

In a separate tank battalion, once assigned to a division for a battle they were often broken down much further. The way they usually did it was each regiment of the division would get a company, and then each battalion of the regiment got a platoon. The HQ platoon would be held in reserve or used to beef up a special combat team.  One tank platoon could get to know a battalion of troops very well if they worked together often, and that made for a better team. The longer they stayed assigned together the closer that bond got. Some Army officers even encouraged the exchange of men in bivouac, so infantry and tankers could see how the others lived.

The Tank Company:  17 Shermans Tanks and one Assault Gun or 105 Tank, 5 Officers, 39 NCOs, 73 EM

The next unit up in the Battalion is the Medium Tank Company. An early war US Medium Tank Company was made up of 3 tank platoons containing 5 Lee tanks, and an HQ platoon with 2 more Lee tanks, and 1 jeep and 1, M2 halftrack. They also had an Admin and Mess platoon, with 2, 2 ½ ton trucks, 1, 2 ½ Kitchen truck, and 1 self-propelled 37mm GMC.  Last but not least, a Maintenance platoon, made up of 2 M3 Halftracks with winches, and 1 Jeep. To run this outfit, you needed 5 officers, and 144 enlisted men, including 40 NCOs, but it was pretty primitive compared to the later TO&E.

Lee Company, March 1942

HQ Section: (2) Lee Tanks (1) M2 Halftrack and (1) Jeep

Tank Platoons: X(3) Platoons with (5) Lee tanks in each

Admin, Mess, and Supply Section: (2) 2 ½ ton truck (1) 2 ½ Ton Kitchen Truck (1) SP-AT gun

Maintenance Section: (2) M3 Halftracks (1) Jeep

Personnel: (5) Officers, (144) EM

A later war Sherman Company is made up of three Platoons, just like the example we just talked about and a headquarters platoon with two gun tanks and an M4, or M4A3 105 tank or M7 Priest.

The unit has shrunk a little, B Company has 5 Officers, 39 NCOs, and 73 Jr. EMs The HQ Platoon had three tanks, a pair of M4 tanks of any 75/76 variety for the Company Commander and 1st Sargent. The third tank would be an M4A3 105 tank or an M7 priest if the 105 tank was in short supply. The HQ platoon would also have ARV assigned.

It would also have a maintenance section and admin, mess, and supply section attached. This part of the company HQ would have their own trucks and jeeps and would hang back with the ARV and the 105 tank while the fighting was going on. Sometimes the truck would run ammo out to a tank or the ARV would move out to get a tank unstuck or deal with another problem of that type.  It would not be uncommon for the men in the HQ platoon not assigned to the combat vehicles to not see the rest of the men in the company for weeks at a time when assigned to a separate tank battalion. When part of an armored division, the companies worked together, and the company commander would lead his company into battle. One of the main differences here are the 105 tanks or M7 Priests and the Tank ARV, that the early company lacked.  They had fewer trucks since they were moved into the battalion Service company.

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Sherman Company, Late 1943

HQ Section: (2) Sherman Tanks (1) Sherman 105 tank or M7 GMC (1) Jeep

Tank Platoons: X3 (5) Sherman tanks

Maintenance Section: (1) M32 ARV (1) M3 Half Track (1) Jeep

Admin, Mess, and Supply Section: (1) 2 ½ Truck with trailer

Personnel: (5) Officers (112) EM

The Light Tank Company: 17 M5A1 Light Tanks or Chaffee tanks late in the war, 5 Officers, 35 NCOs, and 54 EM

Now is as good a time as any to talk about the light tank company. Early in the war, when the Lee was the main tank, no light tanks were included in the tank battalion TO&E, but they were added by 1943. So from 1943 onward, the tank battalion had four combat companies, three medium tanks, and one of lights. There were also light tank battalions that had all light tank companies.

The light tank company was configured more or less the same way as the medium tank company, three platoons of five tanks, with two HQ platoon tanks. They were used was very different. Even early in the war in North Africa, the light tanks armed with 37mm guns were having trouble. When used in the recon role they had to rely on speed alone to get them out of trouble since the gun wasn’t very useful against anything but the lightest of armor.

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An M4A1 and M5 Stuart

They were fast, and they had lots of machine guns, so they could be used, to a degree against soft targets, so they were used for rear security, messenger duty, and screen flanks and scouting. They would be useful against infantry without good AT weapons. Late in the war when the M24 Chaffee started showing up, these light tank companies really got some teeth, in a very nice little package. The M24 had a 75mm gun that was an improved version of the M3 75mm gun and had a concentric recoil system. Once they got the new light tank they probably took scouting duties back on to some degree, but even the Chaffee was a light tank, and all sorts of AT weapons knocked them out pretty easily.

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an M24 Chaffee

 

Light Tank Company late 1943

HQ Section: (2) M5 Light tanks (1) Jeep

Light Tank Platoons: 3X (5) M5 Light Tanks

Maintenance Section: (1) Jeep (1) 1 ARV (1) M3 Halftrack

AM&S Section: (1) 2 ½ ton truck with trailer.

Personnel:  (5) Officers (89) EM

The Tank Battalion: 53 Medium tanks, 17 Light Tanks, 6 Assault guns or 105 Shermans, and 3 SP 81mm Mortars, 40 Officers, 220 NCOs, and 460 EM

When you look at the tank battalion and compare the early Lee tank battalion to a later Sherman one, there are some very big differences. This stemmed from the lessons learned fighting these units in North Africa. The size of the battalion grew overall but some units got a little smaller.

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M3 Lee

A Tank Battalion in March of 42

Battalion HQ  

HQ section: (1) Motorcycle (3) Jeeps (1) M2 Halftrack

Recon Section: (2) Motorcycles (4) Jeeps (1) M2 Halftrack

Tank Section: (3) M3 Lee tanks

Headquarters Company

HQ Section: (2) Jeeps (3) 2 ½ ton trucks (2) M3 Halftracks

Assault Gun Platoon:  (3) T30 75mm HMC (3) M3 Halftracks with Trailers

Mortar Platoon: (1) M3 Halftrack (3) M4 81mm Mortar Halftracks

Tank Companies

Company A:  (2) Jeeps (17) Lee Tanks (1) SP AT Gun (3) 2 ½ ton Trucks (3) M3 Halftracks

Company B:  (2) Jeeps (17) Lee Tanks (1) SP AT Gun (3) 2 ½ ton Trucks (3) M3 Halftracks

Company C:  (2) Jeeps (17) Lee Tanks (1) SP AT Gun (3) 2 ½ ton Trucks (3) M3 Halftracks

Total Men: (27) Officers (572) Enlisted

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This was not a small unit, but by 1943 it had grown a lot. The new TO&E has a whole new Light tank Company and Service company really fills the unit out.

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A Tank Battalion in September of 1943

Battalion HQ Company

Battalion HQ Section: (4) Jeeps (2) M3 Halftracks

Company HQ: (1) M3 Halftrack (1) Jeep

Tank Section: (2) M4 Sherman Tanks

Maintenance Section: (1) M3 Halftrack (1) Jeep

AM&S Section: (1) 2 ½ Truck and Trailer

Recon Platoon: (1) M3 Halftrack (5) Jeeps

Mortar Platoon: (3) M4 81mm Mortar Halftracks (1) M3 Halftrack

Assault Gun Platoon: (2) M3 Halftracks (3) M4 105 Shermans (4) Ammo Trailers

Medical Detachment: (2) ¾ ton WC truck (2) M3 Halftracks (1) ¾ ton ambulance (1) Jeep (4) ¼ ton trailers

Total Men: (15) Officers (154) Enlisted Men

Service Company

HQ Section: (1) ¾ Ton Weapons Carrier Truck

HQ Maintenance Section: (1) Jeep (1) 2 ½ Truck (1) ¼ Ton Trailer

Battalion Maintenance Platoon: (1) Jeep (1) ¾ WC Truck (2) M32 ARV (2) 6 Ton M1 Wrecker (2) 2 ½ Ton Truck (2) ¼ Ton Trailers

Administration, Mess & Supply Section: (1) 2 ½ Ton Truck (1) ¼ Ton Trailer

Administration & Personnel Section: (1) 2 ½ Ton Truck (1) ¼ Ton Trailer

Battalion Supply and Transportation Platoon:  (1) Jeep (1) ¾ WC Truck (29) 2 ½ Trucks  (13) M10 Ammo Trailers

Total Men: (4) Officers (112) Enlisted

Tank Companies

Medium Tank Company A:  (2) Jeeps (17) M4 Shermans (1) M4 105 Sherman (1) M32 ARV (1) M3 Halftrack (1) 2 ½ ton truck (2) ½ trailers

Medium Tank Company B:  (2) Jeeps (17) M4 Shermans (1) M4 105 Sherman (1) M32 ARV (1) M3 Halftrack   (1) 2 ½ ton truck (2) ½ trailers

Medium Tank Company C:  (2) Jeeps (17) M4 Shermans (1) M4 105 Sherman (1) M32 ARV (1) M3 Halftrack   (1) 2 ½ ton truck (2) ½ trailers

Light Tank Company D: (2) Jeeps (1) M3 Halftrack (17) M5A1 Tanks (1) M32 ARV (1) 2 ½ Ton Truck (2) ½ Trailers

Battalion Personnel Total

Officers: 39

Enlisted Men: 709

This image is of the 752nd Tank Battalion in Bologna Italy. They are in the Plaza Emanuel and it still looks like that to this day. I found the info for the image on the Sherman Minutia site, along with a much larger version.

This was the whole kit and caboodle, three medium tank companies, one light, six assault guns, and a service company with three more ARVs. In an AD, all these units would work and train with each other for years. There weren’t that many revisions to the way ADs were configured, so the same units would stay in the same Armored Division for years or the whole war. There would also be a fair amount of competition, not only among the battalions but amongst the companies in the battalions.

They would also have a chance to work with the same Armored Infantry Battalions, and the tank infantry team tactics would become ingrained, and they would have far less trouble working together than many of the independent tank battalions. They also had no issues with supply, since they were part of the division’s supply system.

The independent battalions had a tougher life in many cases. Many got moved around from Infantry Division to Infantry Division, and how well the infantry knew to work with the tanks varied a lot. This could mean the infantry officers may not know the best way to employ armor and would often ask the tankers to things that a tanker knew were suicidal. This sometimes resulted in the tanks being forced into attacking infantry in towns, or even just dug in positions alone, and in the few cases they succeeded, if they were not relieved or supplemented by infantry, they would be pushed off the objective by being overwhelmed by sneaky infantry who can surround tanks without support. They also spent more time on the line than the AD battalions.

They also had to order the supplies, including spare parts through the ID they were attached to, and if the ID supply officers had no experience with this, shortages could take place. The experiences of the independent battalions really varied though. Some worked with the same ID the whole war, others got moved around so much no one got used to them or vice versa, and of course, there was a range of experience in between.  Often though, the independents rarely worked in more than platoon size groups, and the only time they would see each other on a regular basis is if they were supporting units in the same fights, or after the battles when the units went into the reserve to rebuild, but in many cases, this is where the tank battalion was detached and sent to another ID in combat.

9th Armored Division, Westhousen, Germany, 10 April 1945
9th Armored Division, Westhousen, Germany, 10 April 1945

One final thing to keep in mind about these TO&Es, is they are for an ideal, or full-strength unit. Once in combat, and sometimes even before, because of shortages of items, vehicles, or people, any given tank battalion might be missing several people or vehicles.  Once the unit was in combat, and usually, they wouldn’t be deployed unless they were pretty close to their authorized strength, combat losses would be replaced based on the replacements in depots on hand, as would vehicles. Plus, at any given time several tanks, halftracks or trucks, but if the items were not in depots, they went without until they were. The same with men, and once in combat, they would almost never have a full complement of officers and men.

Sources: The 100thwwII.org websites page on the 784st TD, Armored Thunderbolt, US Tank and Tank Destroyer Battalions in the ETO 1944-45 by Zaloga, Yeide’s TD and two separate tank battalion books, Sherman by Hunnicutt, Combat Lessons, The Rank and file, what they do and how they are doing it 1-7, and 9.  The Sherman Minutia Site, Son of a Sherman by Stansell and Laughlin, M4 Sherman tank at war by Green, Tanks are a Might Fine Thing by Stout, the Lone Sentry, TM9-731B M4A2,  TM9-750M3, TM9-752 M4A3, TM9-754 M4A4, TM9-759 M4A3, TFKSM 17-3-2 Armor in Battle, FM17-12 Tank Gunnery, FM17-15 Combat Practice firing, FM17-30 The Tank Platoon 42, FM17-32 The Tank Company medium and light, FM17-33 The Armored Battalion, FM17-67 Crew Drill and Service of the Piece M4 Series, Another River, another town by Irwin

#16 The Sherman’s Motors: Four Motors Made It Into Production.

The Sherman Motors: Why So Many, And Why The Weird Ones?

The Sherman had four different motors that made it into production tanks. The R975 radial, The GM 6046 ‘twin’ diesel, the A57 multibank, and the Ford GAA V8.  There was also a Caterpillar motor they were trying out I cover in the Shermans of the Future section.

There are several reasons the US went with the radial aircraft engine instead of a dedicated tank power plant, and this was mostly due to lack of money to develop tanks and their drivetrains between wars. When the US got serious about tank motors, there were a limited number of choices and the R975 was the best one. Then they turned to the US auto industry for other motor ideas, but only after the war was clearly looming. The US Government went to General Motors, and Chrysler, and asked for a tank motor ASAP, they got motors ASAP, but they were lash-ups, but they ultimately worked well. In this case, desperation produced the weird motors, and American automotive know-how, made them reliable.

GM came up with their twin bus motor, the 6046 and it was well-liked right from the beginning. Then Chrysler came out with the nutty but fantastic A57. The US Army didn’t like either and didn’t want to even use them for training. If the British hadn’t been willing to take the A57 versions, the Army would have regulated them to training use only. It wouldn’t be until Ford figured out the bugs in the GAA V8 that the US Army would make the switch from the R975. R975 powered M4s and M4A1s would serve with the US Army until the end of the war in just about every unit that used Shermans though, and they would not be phased out until after the war.

Post-war many A4 tanks would have R975s put in them, or in much rarer cases, the 6046.  Parts of the A57 became rare post-war, and people who knew how to keep them working were probably rarer. I’m pretty sure almost all A4s used post the 50s were converted to one or the other of these motors. Conversions to the Ford GAA were not done as far as I can tell, I think because the US Army was stingy with this model and spares for it, so they could keep them for their own use or close allies.

The Continental R975 C1/C4: The Motor the Sherman was designed around

The Continental R975 C1/C4:
Type: 9 cylinder, 4 cycle, radial
Cooling system: Air       Ignition: Magneto
Displacement: 973 CI    Bore and stroke: 5×5.5 inches Compression Ratio: 5.7:1
Net Horsepower: C1/C4 350/400 hp           Gross Horsepower: C1/C4 400/460 hp
Net Torque: C1/C4 800/ft-lb/940/ft-lb       Gross Torque: C1/C4 890ft-lb/1025ft-lb
Weight: 1137 lbs dry    Fuel: 80 Octane gasoline     Engine Oil Capacity: 36 quarts

This motor was a license-built version of the Wright R-975 built by Continental for tank use. It had been around nearly ten years and used in civil aviation before the army started putting it in tanks, starting with the M2 medium in 1939, and would go on to produce more R-975s than Wright ever would, 53,000 motors total. The military version put out more horsepower than the civil version as well.  This was a solid and reliable tank motor, but not ideal. It was a little underpowered and had to be revved up a lot to get the tank moving. The Army considered this a superior choice over the 6046 diesel and A57 motors, probably because it required a lot less maintenance than the other two motor choices.  This motor would be swapped into M4A4 hulls by the French post-war, the French would use the A4, and A2 with the original motors during the war.

Another reason the motor was not ideal was the shape, the R975 is wide and tall, and this dictated how large the rear hull of the tank had to be.  The only motor larger was the A57, and it was huge. There are still a lot of Shermans still running with this motor, either in civilian collections, or museums that keep running tanks.

The General Motors 6046: The Motor GM Came Up With To Power The Sherman

The General Motors 6046:
Type: 12 cylinder, 2-cycle, twin in-line diesel
Cooling system: Liquid Ignition: compression
Displacement: 850 ci     Bore and stroke: 4.25×5 inches Compression Ratio: 16:1
Net Horsepower: 375    Gross Horsepower: 410
Net Torque: 1000 ft-lbs Gross Torque: 885-lb
Weight: 5110 lbs. dry     Fuel: 40 cetane diesel oil    Engine Oil Capacity: 28 quarts

First used in the M3A3 and M3A5 and then in the M4A2. This motor tied two GM supercharged truck diesel together on a common crankcase. The motors could be run independently, so if one was damaged the other could be used to get the tank back to a repair depot, or to keep fighting. The engine weighed more than the R975 but had better torque characteristics, and the tanks with this motor handled low-speed operation better because of the superior torque.

This version was ruled out for use by the Army because they didn’t want to complicate the tank supply chain by adding another fuel to it. This motor was well-liked by its users, and the only version of the Sherman the Soviet Union would take via lend-lease were the ones powered by this motor.  The Army testing of this motor found it was as reliable as or more so than the R975.

M4A2 6046 underside

This motor would run and drive the tank if one of the diesels failed. It has also been reported the Russians would use the ability to only run half the motor to sneak the tanks closer to German lines without being heard. They were impressed with how quiet the Shermans tracks were.

The early drawbacks to this motor were tied to its air cleaner system for the motors; they would clog quickly and required a lot of maintenance. Getting the two clutches for the motors synchronized was difficult on early tanks with these motors as well and this made for short clutch life.  There were some other teething troubles with the fuel injectors and other problems, but these would all be solved early in the M4A2 productions, including improved injectors, air cleaners, and clutch system.

The US Army hadn’t wanted to use tanks with this motor in combat, but they ended up doing so since this motor also powered the M10.

 The Chrysler A57 Multibank: The Motor Chrysler Came Up With To Power Tanks, It Was Crazy, And It Worked!

The Chrysler A57 multibank:
Type: 30cylinder, 4-cycle, multibank
Cooling system: Liquid Ignition: Battery
Displacement: 1253 ci   Bore and stroke: 4.37×4.5 inches Compression Ratio: 6.2:1
Net Horsepower: 370    Gross Horsepower: 425
Net Torque: 1020 ft-lbs   Gross Torque: 1060 ft-lbs
Weight: 5400 lbs. dry      Fuel: 80 octane gasoline     Engine Oil Capacity: 32 quarts

This motor was a bit of an orphan in US Service. It powered the M3A4 and M4A4. The Army used the motor for training and tried to pawn a few off on the Marines. That lasted about two months at the Marine Tank School. The ever-growing need for tanks by the British ultimately solved what to do with the tanks that ended up with this motor. They would end up taking nearly 8000 of them. Chrysler sent tech reps to England with these tanks and showed the maintenance crews how to keep them running.  This worked well and the engines served their purpose with little trouble. Often powering the best pure AT version of the Sherman, the Sherman VC Firefly.  This motor saw a lot of use, during the war, and after with many countries being given Firefly Shermans to help out their recovering militaries. Some even ended up in South America, but I’m not sure what versions. This is my favorite Sherman motor because it’s so absurdly complicated, it’s almost German, but it actually worked, so not German at all.

M4A4 labeled image front A57one water pump

This motor was fairly robust and would continue to run and allow the tank to move with three of the five-cylinder banks not working. This would make the tank severely underpowered but would be useful to get it back to the repair yard or onto a dragon wagon. I’m sure it was much more common to have one of the five not operating right, and that level of power loss would be an annoyance, but wouldn’t keep the tank from fighting if it was really needed.

a57 top multipump

m4a4 a57 throttle linkage
The A57 Carb Linkage

During the war, Chrysler really went to bat to keep these motors working well. Since it was based on a motor already long in production, spare parts were readily available. I’m not sure how long support for the motor lasted after the war. I doubt it was very long, and American car parts were probably not easy to acquire to keep these motors running. Because of this, the M4A4, more than any other model seems to have its engine replaced in post-war service.  I’ve read about the twin diesel and the R975 being swapped in.  There are a few M4A4s around in Europe with running A57 motors, both fireflies if I recall right.  You have to love anyone willing to keep one of these motors running.

a57 single pump right side a57 right side multiopump

Daily maintenance could be done with the motor in the tank, carburetor and timing adjustments, fluids and filters, and things like that. If anything major needed to be fixed, one of the motors had a bad piston or valve, or even something minor like a big vacuum leak on the intake of one of the motors, or even a leak in the cooling system, the whole motor would have to be pulled. Chrysler knew this and made getting the motor in and out as easy as possible, including huge lifting eyes built on the common block to help lift the motor out.  The British probably had several depots set up to rebuild A57 power packs that were in need of major work, and Chrysler made a lot of spare motors and parts to support the motor.

a57side single waterpump A57 side view multipump

To be fair, many serious problems with the other tank motors would require pulling the motor to fix them as well.

The Ford Motor Company GAA V8: The Best Sherman Motor

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The Ford GAA:
Type: 8 cylinders, 4-cycle, 60-degree V8
Cooling system: Liquid           Ignition: Magneto
Displacement: 1100 ci              Bore and stroke: 5.4 x 6 inches Compression Ratio: 7.5:1
Net Horsepower: 450 Gross Horsepower: 500
Net Torque: 950 ft-lbs               Gross Torque: 1040 ft-lbs
Weight: 1560 lbs. dry                Fuel: 80 octane gasoline Engine Oil Capacity: 32 quarts

The Ford GAA only made it into one Lee as a testbed. But it powered a lot of Shermans, both large and small hatch. It would go on to be the motor of choice for the US Army for the rest of the war, and in the next tank, the M26. Just look at the numbers above and compare them to the rest of the motors. The GAA is really a much better motor for a tank in the Shermans weight range. This tank was not lend-leased to the other allies in large numbers if at all. The USSR may have gotten one to evaluate, the UK too, but the Army wanted to switch over to this and stop using R975 powered tanks. After the war, the only Shermans they kept were M4A3 76 w tanks, and over time they converted as many of these to HVSS suspension as possible. They went as far as swapping T23 turrets from M4A1 76 W tanks onto M4A3 75 hulls. The army would produce several other gas-powered tank engines, but none would really shine like this one did in the Sherman.

The motor started life as a V12 Ford had designed to compete with the Rolls Royce Merlin, after a deal to produce the RR engine fell through. Ford was incensed that a deal could not be worked out and decided to build his own V12 aircraft motor. When he tried to sell it to the Army he was turned down, but later when the army needed tank motors he used the V12 as a basis for the V8, by removing 4 cylinders. As a tank motor, it was under very low stress putting out only 500 horsepower, and could have been really upped in horsepower with a few tweaks.

This motor does not get much credit for how advanced it was. The much talked about, and unreliable as hell,  German Maybach HL 230 P30, the motor used to power the Tigers, and Panther tanks, was not nearly as advanced, or as reliable as this amazing V8. This V8 is apparently the largest gas-powered all-aluminum V8 ever produced. It has some very advanced features, even for a modern V8, like a one-piece cast aluminum block with dual overhead cams and four valves per cylinder a true, dual, overhead, cam, motor, or DOHC. It had a very innovative 8-way power drive system for its accessories, like the generators, fuel and water pumps, and two magnetos. The motor used no belts or chains, everything was gear and shaft driven.

M4A3 firewall diagram engine in place m4a3 engine compartment rear

This motor saw post-war use in civilian hands, from powering logging equipment, to use as stationary pump motors. The most interesting post-war use is in pro-tractor pulling and hotrod use. These installations in most cases just update the intake and exhaust using modern carbs, but in one crazy case down in Brazil they have updated a GAA with coil and spark plug and crank sensor` computerized ignition, fuel injection and twin turbos, and just 8 pounds of boost it makes 1500 hp, with a higher boost number the engine is capable of 3000 HP. For more info on these modifications and some pics, check out this link.   

GAA Data Sheet

Ford GAA V8 Data Sheet

gaa ignition wiring diagram GAA throttle linkage

Sources:  Sherman by Hunnicutt, The Sherman Minutia Site, Son of a Sherman by Stansell and Laughlin, M4 Sherman tank at war by Green, Tanks are a Might Fine Thing by Stout, TM9-731B M4A2, TM9-731G M10A1, TM9-745 GMC M36B2, TM9-748 GMC M36B1, TM9-750M3, TM9-752 M4A3, TM9-754 M4A4, TM9-759 M4A3, TM9-1725 R975 C4, TM9-1731B Ford motors(GAA, GAF, GAN), TM9-1750F A57 Multibank

# 15 Turrets: They Are The Combat Power Of The Tank

Turrets: They Rotate, and have Guns

Cute puppies!
Marine Cleaning his Tommy gun on a Late model M4A3 75 Sherman. Note the all-around vision cupola with periscopes mounded in the center of the hatch.

The Sherman had two turret types the 75mm turret and the later T23 turret with the M1 series of 76mm guns. The Jumbo had an up-armored version of the T23 turret.

split hatch details

One of the things that really set the Sherman apart from its peers, and gave it very good longevity, was the size of the turret ring. The Shermans were 69 inches, positively huge for when it was designed, the early T-34 had a 56-inch ring, and the later version with an 85mm gun had a 63-inch turret ring. Nazi Germans are not very good in this area, PIII having a 60-inch ring, PIV having only 63 inches, and the Panther only having a 65-inch ring. Even the Tiger wasn’t huge, at only 70 inches! So what makes the size of the ring important? It is one of several factors that determine the maximum size gun you can mount on the tank. The other factors are the mechanical reliability of the vehicle and its load capacity, and how good the country building the tank was at making recoil absorption systems for the guns. The combination of automotive reliability, load capacity, turret ring diameter, and turret size allowed the Sherman to be up-gunned for decades. These factors were far more important than armor thickness when it came to the Shermans longevity. That the Sherman received more powerful guns than the Panther had, or could have had, is just one more reason why the Sherman was such a great tank, and better than the Panther.

turret collector ring
The turret collector ring allowed the turret wiring to go into the hull and still allow a 360-degree traverse and not tangle any wires. All Shermans had essentially the same one.

Now let’s talk about turret drive motors.  There were three types used on the 75mm Shermans.

Oilgear: All models of Sherman tank had both powered and manual turret traverse. They did try various brands and types though. The preferred on the early Shermans were the hydraulic mechanism made by Oilgear Company. The Oilgear unit was more precise because it had veritable sensitivity and more robust since it was able to keep the turret spinning even with minor flaws in the race or ring gear, than the other choices. Oilgear could not keep up with all the factories producing Shermans, so they had to go to other companies.

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The Oilgear traverse system and gunners station in an M4A2 76 HVSS tank
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The Oilgear Traverse System, and foot pedal triggers, and elevation wheel in a restored M4A2 76w HVSS tank

The Oilgear unit was hydraulic but powered by its own electric motor that spun a hydraulic pump and turbine set up to rotate the turret. The whole assembly was small enough to be mounted to the side of the turret, with a fair amount of room for the gunner.

Logansport: This Turret drive was very similar to the Oilgear unit, just not as precise, nor as good at dealing with imperfections in the turret race or ring. This unit was so similar the electric motor powering the hydraulic pump and turbine used the same reduction gears as the Oilgear unit.

The Logansport unit used the same mounting bracket as the Oilgear unit as well. The sensitivity to problems with the tolerances on the turret ring would make this drive more likely to fail from minor damage that the Oilgear unit would shrug off.

Westinghouse: The Westinghouse unit was just a big electric motor hooked to reduction gears. Since the motor ran at a faster speed, it had to be adapted to the stabilizer system but was still able to fit the same space and use all the mounting brackets of the other systems.

M4A4 Armament diagram westinghouse traverse 75mm early turret
Westinghouse traverse controls

The Westinghouse unit had the same problem with minor flaws in the race or was sensitive to tightness in the ring gear.

Now, this would be a quality assurance problem at the factory in most cases. IE, when the tank got to the end of the line, and the QA inspector rotated the turret, and it screeched and slowed down over 10 degrees of rotation, it would be rejected, and sent to the factory’s QA shop to be fixed.  Battle damage might have caused some problems as well, but if the tank took enough of a hit to damage the teeth on the ring, or gear, it was probably going to be knocked out, and in really bad shape. That speculation based on how well many turret rings held up after years on firing ranges when the wreck they were in was restored into a beautiful working tank.

On the later T23 turrets, the Oilgear system was used for traverse control and an improved Westinghouse stabilizer was used as well.

The Westinghouse stabilizer: All models of the Sherman but the 105 armed tanks had a stabilizer to control the main guns in elevation while on the move. It used a gyroscope and hydraulic power pulled from the turret drive system to keep the gun steady in the vertical while on the movie. The system is often disregarded as an advantage by detractors, for a few reasons, but none are valid in a technical sense. The stabilizer was a very advanced piece of kit, and something the Germans could not copy, and never installed a similar system on a wartime tank. That it was complicated and the crews lacked training in using it, doesn’t mean it didn’t work and offer advantages to crews who bothered with it.

The original stabilizer was a little complicated to set up properly since many armor units received their tanks and maybe some manuals for them, when they formed, they often did not have a single man in their company who really knew how to make the stabilizer really work. This lead to it being turned off by a lot of early war crews. The wrongheaded belief the equipment was useless followed that. The Army did a test on it and found the stabilizer, when set up, and used by a crew who knew how to use it, it helped a great deal in getting off a fast first shot when the tank came to stop to shoot.  If the tank rocked, the gun stayed more or less on target. This was a big advantage to getting that all-important first shot/hit in combat.

The Westinghouse stabilizer was improved and simplified in the second generation Shermans, the large hatch 75 and 76 tanks would have gotten it.  It was easier to set up and maintain, and the Army worked on getting crews trained on it.

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M3 2 inch Mortar

The M3 2 inch Smoke Mortar:  The M3, 2-inch smoke mortar was installed in the turret, with the muzzle opening on the forward left of the turret, on both the 75mm and 76mm gun turrets.  It was added to the tank at the request of the British and was loaded and fired by the loader. The mortar was loaded from inside, but protruded into the loader’s space, and was not well-liked. It could only be aimed by rotating the turret, and not all late model 75mm and 76mm turrets got them. Postwar, most were removed and the hole welded over.

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An M4 Composite hull, probably in the Philippines, with a good shot of the late model, split commanders hatch

The Hatches:  The Sherman’s turret started off with a single large split commander’s hatch. This hatch incorporated the m2 .50 HMG mount and rotated. It also had a standard periscope mounted on one side of the split hatches. This hatch went through several changes throughout its long life. Initially, the split commander hatch just depended on the weight of the armored hatch cover halves to hold them in the 45-degree angle position that sat in when open. They could be knocked loose when the tank was moving over rough terrain, and really hurt the commander.  They added a pair of hatch locks at the factory and fixed them in the field with kits. The final version of the split hatch had internal springs in the hinges to hold them open. There was also a version with a defect that passed factory inspection that showed up on some M4A1 76W tanks, where the split loaders hatch, essentially the same hatch that had been the commander’s hatch, was used for the loader, .50 M2 mount, and all.  This was fixed pretty quick though, and then the hatch was replaced by the oval loaders hatch.

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In this massive image of an M4A1 76w tank, that has been modified with a flamethrower, after being repaired, note it has the split loaders hatch with the flaw that won’t let them open all the way.

When the second generation Shermans with the T23 turrets went into production, they all got much improved all-around vision cupolas. There must have been a shortage of contractors who could make it, because it was in short enough supply, the second-gen large hatch, M4A2 75s, M4 Composite hulls, and M4 (105) tanks were all built with the original split commanders hatch.  The all-around vision cupola production was reserved for tanks armed with the M1A1 gun.  The cupola offered very good all-around vision, with six armored glass viewing blocks, that were all replaceable, and a larger periscope mounted in a rotating center section of the hatch door. Towards the end of the war, the new cupola became more available and was fitted to some of the ultimate production M4A1 75, M4A3 75w tanks, and M4A3 (105) tanks.

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in this nice photo of an early production M4A1 76w Tank with the split loaders hatch. It’s also a pretty good shot of the all-around vision cupola

The oval Loaders hatch: The version of this hatch on 75mm turrets looked the same but was slightly smaller than the one used on the T23 turrets. The hatch was a spring-loaded oval hatch, either just big enough to get through or, big enough to get through comfortably, in the T23 versions. On the T23 turrets, when the oval hatch was installed, a new fully rotating periscope foreword of the hatch replaced the one that was mounted in the old split hatch.

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Soviet M4A2 76W tanks with oval loaders hatch.
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A late production M4A2 75 with a large hatch hull, oval loader’s hatch, on what is probably a high bustle turret, with a split commander’s hatch.

. . .

Now for a final bit of information on the turrets and the stuff mounted on them. Over time the turrets picked up an external vane sight the commander could use to roughly put the gunner on a target, it looked like a whale fin in front of the commander’s hatch on older 75mm Shermans. This was refined into a more useful, and less odd-looking site that could be used from inside or out of the turret.  The .50 caliber machine gun mount started on the commander’s hatch, eventually moved to the loaders hatch, and then to the middle between the two hatches.  There was also a spotlight mount added, and it ended up being on late 75mm turrets, the T23 76mm turrets, and even retrofitted to older 75mm Shermans.  The mount had an armored plug, the spotlight plugged into, and could be controlled from inside the tank, much like the spotlights you see mounted to the side of police cars. The turrets also started out with no brackets for storing the heavy machine gun, but they started showing up on 75mm turrets and were on almost all T23 turrets.  Even where the lifting eyes were moved around on the turrets.

♠♠♠

From looking at period pictures, it was very common for the gunner or loader to ride standing in the commander’s hatch, while he was in it as well, the split hatch cupolas were that big. I thought I wouldn’t see the practice on tanks with the all-around vision cupola, but I found a few where the crews did it there too.

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This Marine M4A1 in the jungles of Cape Gloucester has its commanders hatch being shared by two crewmen

 

Riflemen of the 29th Marine Regiment ride a M4A3 Sherman 105mm of Company A, 6th Tank Battalion during the 6th Marine Division's drive on Chuda along the west coast of Okinawa. After expecting a contested landing on April 1, 1945, and seeing little of the Japanese, the Americans were in high spirits as objectives are taken ahead of schedule in Northern Okinawa; the Shuri Line would rob them of their high morale. The 29th Marines cut off the Motobu Peninsula and seized Chuda at 1200 Hours on April 6, 1945. Tank-infantry teams encountered sporadic resistance during the initial invasion; most problems were from the Japanese blowing bridges as they retreated inland. Destruction of bridges had been inept; frequently only a span of the bridge had been blown or cracked. The engineers cut quick bypasses for the vehicles, repairing the broken spans later. 500 M4A3 Shermans with the M4 105mm gun were built in late 1944. Later versions of the 105mm Sherman had a more advanced horizontal volute spring suspension (HVSS) with wider tracks that allowed for a smoother ride. Note partially dismantled deep wading gear to allow the M4A3 to move through deep water during the landings a few days before. The M4A3 Sherman with the M4 105mm howitzer was not popular with the tankers, who preferred the M1 76mm high-velocity gun in case of tank-against-tank engagements. However, the 105mm-equipped Shermans were very popular with ground troops, who used tanks as mobile pillboxes, taking out Japanese positions with point-blank high explosive fire.
On this M4A3 105 in Marine Service, you can clearly see the commander and probably gunner sharing the all-around vision cupola!
Classy-Peg-passing-destroyed-Japanese-Shinhoto-Chiha-tank-on-Luzon-in-the-Phillipines-17-Jan-1945
An Army M4A3 75 tank with a split commander’s hatch, oval loaders hatch, and the commander and gunner sharing the split commander’s hatch, somewhere in the Philippines.

. . .

M4A4-Sherman-latrun-6
An M4A4 that has been modified to take a different motor, with a mid-production 75mm turret, with split commanders hatch, and a welded up pistol port. It also has the stubby mantlet, and you can just make out the original commanders vain sight in front of his hatch

 

The standard 75mm Turret:  The Sherman’s First Turret, It Had Many Minor Changes

The standard 75mm turret started out with a stubby rotor shield that just covered the base of the 75mm gun. These early turrets didn’t have a direct telescopic sight for the gunner either. The gunner had to rely on the M4 periscope to aim the gun. The turret had one large hatch for the whole turret crew to get in and out from and a pistol port on the loader’s side that could be propped open and spent 75mm shells dumped out.  The loader and commander had fully rotating periscopes to view the world through, the commander’s periscope was in his hatch, the loaders right above his station, and the middle of the turret roof had an armored ventilator. Many of these turrets had a weak spot in the armor due to an area machined to fit the turret drive. This area was covered with additional armor once the problem was discovered.

207786550-2 M4 wrecking yard
In this shot of a Sherman wrecking yard in Europe, you can see the early 75mm turret with depot or even factory level rebuilds, on these tanks before they were knocked out. They could be M4s or M4A3 tanks that were used in the US for training and refurbished on shipped to the ETO. You can see the split commander’s hatch, though missing the hatch doors on two of them, the full-length gun mantlet, the welded on cheek armor over the weak spot, and the commander’s old-style vane site.

The small rotor shield and lack of telescopic sight were some of the first production line changes, and older tanks were field modified with kits to update them, often only covering half the turret with added armor on the mantlet to protect the new telescopic sight. The new factory full-size rotor shield covered the majority of the turret face with much thicker armor. The next big change was a weak spot in the right side of the casting where a thin spot was made while machining the turret for the gun mount was discovered, and armor was welded on the outside of the turret to thicken it back up. Tanks were retrofitted with this armor in the field, and later the casting was changed to include the thicker armor over the area, eliminating the need for the welded on cheek armor.

US775TB_Luzon_45 (1)
This M4 Composite hull tank in the Philippines has the split style commanders hatch on a 75mm turret with most updates

At some point, while all the above was going on someone decided the pistol port was a weak spot and it had to go. So they started welding them closed at the factory, and then the casting had them removed. Then the men in the field went ape poop, and they put it back in, around the time the ultimate 75mm turret went into production, with the thicker armor cast in, the pistol port back, a new all-around vision cupola for the commander and an oval hatch for the gunner.  This would be the final configuration of the 75mm turret. The tolerances used by US tank factories were close enough turrets cast at one factory could be used at another with no modifications. Many older surplus turrets left over from the tank retriever conversion program were used in later production, with all the updates added, and a hatch cut in for the loader. Due to a shortage of all-around vision cupolas, many 75mm turrets with a loaders hatch ended up with the old split style commander’s hatch.

pistolport inside

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This M4 has split commanders hatch, commanders vane sight, full gun mantlet, and welded up pistol port

When hull production switched over to the 47-degree frontal armor configuration, and they went with the large driver and loaders hatches on the M4, M4A2, and M4A3 production, the 75mm turrets needed modification. The hinge for the larger drivers and co-drivers hatches stuck up higher than the older small hatch hulls, they could interfere with the turret’s rotation, since they barely cleared the bustle was the radio was mounted in the back of the turret. The first solution was to notch the bustle a little, but they also changed the turret casting, raising the whole bustle area and making the top of the turret flatter.

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Clod hopper is an M4A3 75  tank, used by the Marines on Iwo Jima

The turret drive motor was either an electric motor driven hydraulic system or a straight electric motor driven system. The hydraulic system was preferred, but when that system was in short supply the electric system was substituted.  The 75mm turret could rotate 360 degrees in 15 seconds with the power traverse. It had a manual traverse system as well, and elevation was handled through a manual wheel.

For the very best in minute detail on this subject, please check out the Sherman Minutia site. One minor bit of trivia about the original style turret, the D50878, and D78461 castings, the ones produced for the 105 armed tanks were unique, in that they had an extra armored ventilator whole drilled in so another one could be mounted. So the 105mm turrets really are 105mm only. I’m still not sure if there is a 1/35mm Sherman M4 105, or M4A3 105 with the correct turret.

 

T23turret
An early T23 turret on an M4A1 76w tank. Not all-around vision cupola for the commander and the split loaders hatch

The T23 Turret: Developed For the Failed T23 program, It Found a New Purpose on The Sherman

T23_SN12_30103061
The origin of the T23 turret, the fascinating T23 medium tank. It used a gas generator-powered electric drive system, but unlike the ones the Germans used on the Elephant, it worked.

While the 75mm turret was still in production and being improved, the T23 turret, taken from the failed T23 medium tank project, went onto the Sherman with the M1A1 gun on the big hatch, wet ammo rack hulls. This turret was larger and could fit the 76mm gun with much more comfort than the basic 75mm turret. All T23 turrets had loaders hatches, though early production T23 turrets used the hatch that had been the commanders hatch on older Shermans for the loaders hatch and used the new all-around vision cupola for the commander. This didn’t last long; it was found the narrow area between the two large hatches on the roof was a weak spot. The big loader’s hatch went away and an oval hatch went in.  These turrets had the same traverse speed as the 75mm turret and the same ROF.

Division-Photos
Pn this M4A1 76w tank you can see the commander in the all-around vision cupola, and the split loaders hatch open

The T23 turret came in around 4000 pounds heavier than the 75mm turret. The automotive systems of the Sherman tank were strong enough to support the extra weight without any real change in performance or longevity. The drivetrain didn’t receive any changes at all as far as I can tell, and only the Jumbo tanks got a different gear ratio in the differential. All the extra weight in sandbags, concrete and real armor did shorten the life of the automotive components but not by a significant amount.

All T23 turreted 76mm gun tanks, had wet ammunition storage, as did the Jumbo tanks, but not all large hatch hulls did. The M4 (105), M4 composites, and M4A2 large hatch 75mm tanks all had dry ammo racks.  The T23 Turret would get the smoke mortar, and an extra periscope hole machined in when the split loaders hatch was replaced with the oval hatch.

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T23 turret on an M4A3 with the 14th AD
14AD_M4A3_Sherman_03_1945
Another M4A3 76 tank with T23 turret serving with the 14th AD

Sources: Armored Thunderbolt by Zaloga,  Sherman by Hunnicutt, Ballistics and Gunnery by Bird and Livingston, The Sherman Minutia Site, Son of a Sherman by Stansell and Laughlin, M4 Sherman tank at war by Green, Tanks are a Might Fine Thing by Stout, the Lone Sentry, TM9-731B M4A2, TM9-731G M10A1, TM9-745 GMC M36B2, TM9-748 GMC M36B1, TM9-750M3, TM9-752 M4A3, TM9-754 M4A4, TM9-759 M4A3,  FM17-12 Tank Gunnery, FM17-15 Combat Practice firing, FM17-67 Crew Drill and Service of the Piece M4 Series

#14 Main Guns: Things That Go Boom, Some Bigger than Others, but None Bad

Main Guns: The Sherman Mounted Six Different Guns, But Not On All Versions, 

The Sherman tank and its chassis was host to a variety of guns.  Most had the M3 75mm gun, or the M1A1 76mm gun, but many were also equipped with the British 17 pounder, the M3 90mm, 3-inch AT gun, and the M2/M4 105mm howitzer.  I will cover each below.

The M3 75mm gun: When it first saw combat, it was a great tank Gun

The M3 75mm gun was a great tank gun for the time the Sherman was first introduced to combat and was based on a well-liked WWI French field gun. When it first saw combat it could punch through any German tank it faced, from just about any angle. It’s a myth the Sherman was designed to only support infantry, though its primary role was not anti-armor, it was still designed to face other tanks.  The gun worked well in the infantry support role as well, with an effective HE and WP smoke round, and a canister round. This gun had a very high rate of fire in the Sherman (20rpm) and was mated with a basic stabilization system. This system did not allow shooting on the move accurately but did allow the sights and gun to be put on the target faster when the tank came to a stop to shoot. No world war two tanks could shoot on the move with a real chance to hit even a stationary tank-sized target. With a twenty-round a minute rate of fire, the Sherman could pump out a lot of HE in support of the infantry, and it was not unheard of for the tanks to be used as artillery. The Sherman tank was equipped with all the gear to act as artillery if needed and was a regular occurrence in the MTO, less so in the ETO.

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M4A2 75

Sherman tanks with the 75mm gun carried between 104 and 97 rounds of main gun ammo. Only 10 to 15% of this ammo was AP, that’s how rare other armor was, HE would make up the majority of the rest of the load, with maybe another 10 to 15% being WP smoke, since this was also a somewhat destructive shell, because it caused fires and WP when it landed on a person was hard to put out. There was also a canister shell, but I think it was only used in the PTO.  The rate of fire on the gun is a little misleading, since depending on the Sherman, you would have between 6 and 12 ready rounds, more on the very early Shermans with ready rounds around the base of the turret basket.  Once the ready rounds were fired, and often, the ready rounds are kept in reserve anyway, to deal with unexpected threats.  Wet Shermans had an armored 6 round ready box mounted in the turret, the rest of the ammo was in armored boxes under the floor. Most wet tanks had a half turret basket or none at all. This was a problem common on pretty much all tanks.

m4a3 75 m70f reticle

The M3 75mm gun was so well-liked, the British essentially ended up converting many of the QF 6 pounders to fire the same round, fired with basically the same ballistics, with the advantage of not needing to modify the current tanks mount.  The WF 6 pounder was a better AT gun, but, its HE round was not very good. The M48 HE round used by the m3 75mm had 1.5 pounds of TNT inside, and since the Sherman could fire them fast, and the shell was fairly handy, it’s easy to see why the gun was good at infantry support.  It really only lacked the ability to pen the frontal armor of the German Tiger and Panther, but those tanks were rare enough, or easy enough to get side shots on, the 75 did the job, and did it the whole war since the 76mm armed Shermans never totaled more than 53% of the Sherman force in Europe. The M3 75mm gets a lot of flak thrown at it by ignorant people who think it was a low-velocity gun that could not penetrate armor. These people must be confusing it with the German KwK 37 L/24 75mm gun that armed the first versions of the Panzer IV.

 

75mm M3 spec booklet MK VI Download. 

The M1/M1A1/M1A2 76mm gun: Made by Oldsmobile, It Was Not a Great Gun, but Did the Job

The M1 series of 76 mm guns went into production before the US Army had any idea of German heavy tanks or the Panther. They were just looking ahead, to keep the Sherman as good a combat weapon as possible, and to stay ahead in the arms race.  They had the 3-inch AT gun on hand and had used it in the M6 and M10, but it was really too bulky to work in a medium tank turret.  The Army decided to design a gun with the same ballistics, but in a much lighter, and less bulky package, in doing so the M1 gun was born.  The gun overhung the front of the Sherman a lot so the Army decided to shorten it over a foot. It still seemed to match the ballistics of the 3-inch AT gun though; guns with the shorter barrel were designated M1A1 guns.  The first three hundred or so guns produced by Oldsmobile lacked muzzle brakes or the threads to install them. Gun’s produced after that had the threads and a protective cap over them so a brake could be installed later. The final variant of the gun was the M1A2, installed in late production 76mm Shermans, this gun always had the muzzle brake, but had a slightly different barrel, with a minor change to the rifling twist.

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M4A1 76W with the unthreaded M1A1 gun

Much of the later large hatch hull tanks were produced with a larger turret to accommodate the M1 family of 76mm guns. This turret came on M4A1s, M4A2s, and M4A3 tanks.  The M1A1 on the early tanks, like the M4A1 76 w tanks used in Operation Cobra, came without muzzle brakes. When firing during dusty -conditions the view of the target would be obscured by dust stirred up from the guns blast, the fix for this was for the commander or another crewman to stand away from the tank and talk to the crew over the intercom, via a long wire, and correct the shots onto the target. Not a great fix…The final fix was muzzle brakes; it took a little while for supply to catch up with demand but they were showing up on Shermans in Europe by late 44, and by March they seemed to be in stock and showing up on tanks that had the protective cap before.

Another problem was the gun was not a huge improvement over the M3 75mm as a tank killer, and was not as good as an HE thrower. As mentioned before, several tank divisions didn’t want the improved Shermans at first. The penetration problem would be partially solved with HVAP ammunition, but by the time it was common, German tanks to use it on were not.   Post-war, ammunition would be further improved and there would be no shortage of HVAP ammo in Korea, so the US Army would soldier on with the gun, in its final improved form, the M1A2.

The M1 series of guns were also stabilized when installed in the Sherman, but it was the same system used with the 75mm gun, offering limited advantages. The Nazi Germans never fielded a stabilization system of any kind on their tanks. Tanks with the M1 and M1A1 guns carried 71 main gun rounds in wet storage racks under the floor, with an armored 6 round ready rack on the turret floor.

M1-M1A1-M1A2 guns 76.2mm Sherman Tank Gun PDF file.

The M3 90mm Gun: The Most Powerful AT Gun the US used During the War.

The US M3 90mm tank gun started out life as an AA gun, a very good AA gun, unlike the very overrated Flak 18/36/37.  As the AA gun was developed, its mount gained the ability to be used against ground targets, with up to -10 degrees depression.  The ballistic performance on the gun was good, but what really made the AA gun shine was the AA gun system that incorporated Radar, and proximity fuses, sci-fi tech to the Germans, but pretty typical American technology for the time, it was the best land-based AA gun system of the war.  Contrary to some claims, it was pretty rare for US 90mm AA guns to be used in the direct fire role. The US Army was rarely desperate enough to have to resort to such tactics.

American soldiers of Patton's Third Army standing in front of their M36 TD while rolling up a Nazi flag they have taken as a trophy after the capture of Bitberg.
M36 with M3 90mm

When the US Army started looking into a bigger AT gun than the 3-inch, the M1/M2 90mm AA gun was a natural choice.  The tank-mounted weapon would be designated the M3, and with a barrel threaded for a muzzle brake, the M3A1. When tested against the British 17 pounder gun, the M3 had slightly inferior performance but was more accurate. The US Army preferred the 90mm over the 17-pounder for various reasons, the biggest being it didn’t have scary flashback out of the breach on firing, making it seem like a somewhat shoddy design. The 90mm M3 would soldier on the in the M26/46 tanks but would be replaced by improved 90mm guns on the M47 and M48.

reticle m76f

As a dual-purpose tank gun, the M3 90mm was good. Its rounds were not too big for one man to handle. It had good AT performance and a more potent HE round than the M3 75mm gun. When installed on the M36 Tank Destroyer, it was able to deal with the rare heavily armored German threat, if the regular Shermans hadn’t already killed it by the time the M36 got there. Since the gun was not overly hot, it didn’t wear barrels out fast, so it could still be used in an artillery role.  

M3 90mm gun data on PDF

The 3-Inch AT gun: An Old AA Gun Finds a New Use

The 3inch AT gun started out life as a AA gun. It was still being used as one for the first half of the war.  It was a natural choice as an AT gun since it was being replaced by the M1/2/3 90mm AA gun system. The gun was large, heavy, and bulky, and the M10 tank destroyer’s turret had to be rather large to fit it.  They were also able to fit it in the T1/M6 Heavy tank, but it was clear it needed a redesign to fit in a smaller turret like the regular Sherman. This ultimately leads to the M1A1 gun discussed above.

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M10 with three-inch gun

There was also a towed AT gun version of this weapon, it was generally not well-liked. It was too big to move around easily by hand, hard to hide, and didn’t have great pen to work well as a fixed gun. At one point in the war, nearly half the Tank Destroyer Battalions were towed and equipped only with the towed guns and trucks to move them. These TD battalions had little luck, and some really got clobbered in the Battle of the bulge.

Ultimately this gun use was more about taking unused guns on hand and getting a decent AT weapon out the door fast, by using them for this new purpose. They were not perfect, and as towed weapons, even really good, but on a mobile platform like the M10 or even the M6 heavy tank they did the job well enough.

3 inch M7 Gun spec sheet PDF download

The M2/M4 105mm Howitzer: Artillery in a Sherman Package

105mmM4gunM4105ShermansFLTSMALLER

The US 105mm M2/M4 howitzer was the biggest gun installed in the Sherman, the versions of the Sherman with this gun were developed to replace the M7 Priest, but never fully did so during WWII.  They were used in the same role, or in limited direct support roles. These tanks did not have a stabilized gun or wet ammo racks but did have a large hatch hull. All 105 Sherman tanks, either M4 (105)s or M4A3 (105)s were produced exclusively by Chrysler. 105 tanks carried 66 rounds of main gun ammo, in dry ammo racks.

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Sherman tanks equipped with the 105 often found themselves pooled with the others from the three companies of a battalion, with the two from the battalion HQ, so the Tank Battalion could have their own mini 105 battery on call. When working with their assigned company, they were often held in the back and supported the gun tank platoons with indirect or direct fire.

The 17 pounder gun: 76.2mm of British High-Velocity Boom Boom

The 17-pounder was developed to replace the 6-pounder, it was clear the 57mm 6-pounder wasn’t going to be able to handle tanks with thicker armor, but it stayed surprisingly relevant late into the war.  The 17-pounder started development in the final months of 1940 and was going into prototype testing in late 1941.  The first few AT guns were made by slapping the gun onto the 25 pounder carriage called the 17/25 pounder, and some were shipped to North Africa, to counter the supposed Tiger threat. The full production QF 17 pounder AT gun was available by the Italian Campaign.

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American Test Firefly with 17 pounder

The main reason the gun was a better AT gun than the US M1A1 gun was the round had a lot more propellant behind the projectile and then the Brits came up with the super velocity discarding sabot round. This new round had very good penetration but had some serious accuracy problems.  The accuracy problems with the SVDS ammo were not fully solved until after the war.  The gun was intended for tank use, but the British Tanks meant for it had too many developmental problems, and were not going to be ready by Normandy landings, so the Sherman Firefly was born. See its own section for more info on these Shermans.

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M4A1 with 76 gun

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M4 105

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What’s left of an M4A3 75w on Iwo Jima

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M36 with M3 90

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Sources: Armored Thunderbolt by Zaloga, Sherman by Hunnicutt, Combat Lessons,  Archive Awareness,  WWII Armor, Ballistics and Gunnery by Bird and Livingston,  TM9-374 90mm Gun M3

#13 The Suspensions And Tracks: A Smooth And Comfortable Ride Was The Goal, And It Was Achieved, Somewhat

Suspensions and Tracks: It Suspends, and gets laid! 

UPDATE! See the new Suspension and Track pages found here this post will no longer be updated, all the latest info I have will be put on these pages to make it easier to find. 

M4 tanks came with three types of suspension the early VVSS, VVSS, and HVSS. The early VVSS suspension system used 16 inch wide tracks. In the link above about Sherman details, you can see all the changes the basic VVSS system went through. The VVSS suspension went from the basic two road wheel one return roller with no support module as seen on the Lee, to the later production VVSS bogies that had bolt-on return rollers, that could be bolted to either side of the suspension unit, and sheet steel track supports and much beefier structures that were still usable on either side of the hull. The suspension was one of the parts of the tank that went through so many minor changes, keeping track of them is out of the scope of what this document is meant to do. The Sherman Minutia site does a great job of covering these changes. These changes had little effect on the performance of the tank; think of them as more of fine-tuning of the basic design for strength, longevity, and ease of manufacture.

What would be the final VVSS, with the return roller that could be swapped to either side, was developed for the M3A4, with the A57 multibank motor. The combo of heavier hull and engine was putting the basic VVSS suspension with the built in return roller under to much stress and causing premature failures. The heavy duty unit was developed to solve this problem was later standardized as the M4 suspension type, though, the bolt on roller and skids would still receive improvements, a beefier skid, and a spacer to lift the return roller, and later a new assembly that raised the return roller higher, the core remained the same. The M3A4 would be the only version of the Lee to receive the heavy duty VVSS suspension units from the factory.

Early VVSS: Using 16 Wide Tracks

vvss early dia

Mid VVSS: Still Using 16 inch Wide Tracks

suspension unit late

vvss suspension broken down
vvss brakedown key
HVSS: The Improved 23 inch wide Track and Suspension System

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late VVSS diagram
Late VVSS diagram the whole suspension

The VVSS was later replaced by the HVSS system that had twenty three inch wide tracks, but the suspension was still a bolt on module. It was very well received and used on many late production Sherman models and a few of the variants. It solved the floatation problem of the narrow tracks with few drawbacks.  Thousands of 75mm Shermans received this suspension coupled to large hatch wet hulls. This would become the preferred suspension type for US Army Shermans, and many 75mm hulls either lost the suspension or had its 75mm turret removed and replaced with a T23 turret and 76mm M1A2 gun after the war

Sherman Idler diagram
Sherman Idler wheel parts

This type of system, that could be unbolted, was much easier to work on or fix when damaged than an internal torsion bar suspension or Christie suspensions found on other tanks. Changing the one bogey setup, or even two and putting the track back together was a lot easier than trying to get the stub of a broken torsion bar out of the hull so a new one could go in.

An experimental Sherman with torsion bar suspension was produced and found to be little better than the basic VVSS tanks, and no better than the HVSS tanks and production was never considered. The HVSS suspension made it onto a lot of things built on the Sherman chassis.  HVSS was also retrofitted onto hulls used in Israel’s M51 Super Sherman program.

Tracks:  They are a weapon too you know

 

The Sherman VVSS had at least 14 different types of track, and there was another 4 typesfor the HVSS. I will cover them in more detail later. Most of the track types were ways to minimize the amount of rubber used in the tracks or to produce an all steel track, as good as the basic rubber and steel T41 track.

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The narrow VVSS tracks limited the Shermans mobility in soft mud, sand, boggy terrain. The Tiger and Panther tanks were better off road than the VVSS Shermans. It’s a good thing they were so rare, and there was a limit to how much mud they could deal with. The mud also accelerated the maintenance problems both these tanks faced and eventually mud got so deep in late 44 no take could go off road much until the ground froze.

end connector wear tracktool tracktooluseThe Army came up with a field expedient solution called a “duck bill” end connector. The was an end connector with a sheet steel foot welded to it, when bolted in place on the track it added several inches to the tracks width in soft terrain. The only drawback was they broke off fairly easy, but were easy enough to replace.  This was a very popular and widespread modification, and many little local factories in France were contracted to produce them. They were also factory produced and installed on production Shermans.

Factory Duckbills
Factory Duckbills (image from the Sherman Minutia site.)

Sources: TM9-1750K Tracks-Suspension-Turret and Hull Mods M4 series,TM9-731B M4A2, TM9-731G M10A1, TM9-745 GMC M36B2, TM9-748 GMC M36B1, TM9-750M3, TM9-752 M4A3, TM9-754 M4A4, Sherman by Hunnicutt, The Sherman Minutia Site, Son of a Sherman by Stansell and Laughlin

#12 The Sherman’s Armor: It Was Better Than The German Armor Of Comparable Weight.

The Sherman’s Armor: Not As Bad As People Like To Say It Was.

Austerlitz
Look at all the dings in this free French M4

The M4 had well-balanced armor in the same class as the other medium tanks of the war. We have covered ‘welded’ and ‘cast’ hulls, but even the ‘welded’ tanks used many cast parts welded to form the plates. In either case, all M4 Shermans used rolled homogenous, or cast homogenous, steel armor. It was well balanced between hardness and ductility and was resistant to spalling and cracking. It was easy to repair and weld.  All versions cast or welded had sloped frontal armor, but the early welded Shermans had a lot of weak spots due to all the welding lines, and thinner armor used in the driver’s hoods. This was solved by adding external plates in front of the hoods. Over time the front plate was simplified to eliminate as many welds as possible, and the later large hatch hulls used a single plate.  Most early welded Shermans used cast armor plates welded together to form the front hull plates.

A mid-production M4 Sherman had 2 inches of armor at 56 degrees. The hull sides were 1.5 inches at 0 degrees, the rear was also 1.5 inches at 0 to 10 degrees. The hull roof was .75 of an inch thick and floor 1 inch under the driver and a .5 inch everywhere else. This version of the Sherman was welded; the front plate was made from many smaller plates welded together, with the cast fittings welded in place as well. This was a lot of welding, and one of the reasons why the cast version was well-liked from a manufacturing perspective because it took a lot fewer man-hours to produce, the problem was, not all the factories could do the large castings.  The hybrid hulls were a solution to the casting capacity problem since more factories could handle the much smaller front casting the highbred used a casting on the front of the hull, and the rest of the hull was welded and very similar to the standard M4 hull.

In some cases, when cast parts were called for, but if there was a shortage, a particular tank maker might come up with their own built-up part instead of cast fitting. This is one of the major reasons why there are so many little details differences between each factory’s version of the tank, they each left a signature on the fittings they used and how they installed them. These details are the thing of nightmares for a scale modeler who really needs to get the details right, the classic ‘Rivet Counter’ could be driven insane by all the places they could go wrong on a Sherman kit.

The M4 would have a cast, 75mm gun turret. These turrets had 3.5-inch thick gun shields, a 2-inch rotor shield, and 3 inches of armor at 30 degrees on the turret face. The sides were 2 inches, and the rear 1. The top was 1 inch thick. This turret armor was the same throughout the 75mm turret run, though many early castings had a weak spot on the frontal armor, near the gunner, this was covered with a large section of welded on armor, and the casting was improved in later versions of this turret, thickening the armor over the weak spot so the add-on armor was not needed. This is much better armor than say the armor on the PIV, and very similar to the armor on the T-34. Most of these mid-production tanks would not have a loader’s hatch unless it was retrofitted at a major tank factory, but this would only be done when a tank was being completely rebuilt.

A mid-production M4A1 would have the same turret, but the hull armor was cast and would be 2 inches at 37 to 56 degrees. The rest of the armor, with the exception of a few places in the hull roof as thin as .5 of an inch, was the same, and there was a contour difference inside the hull. Many of the cast fittings welded onto the M4 would be cast directly into the hull of an M4A1. All spare parts would be interchangeable between these two tanks.

The Shermans armor was pretty good against 37mm and 57mm anti-tank guns. It was ok against 75mm guns like the one mounted on later production PIV tanks. Anti-tank guns larger than 57 mm could be hard on the Sherman and some guns could cut through them like butter. This was no surprise to the US Army, and they had a whole plan worked out to use infantry, artillery, and air support in conjunction with tanks to help them deal with anti-tank guns and other tanks. The Shermans M3 75mm main gun was a very good gun for handling AT guns, it was accurate, had a high rate of fire, and an excellent HE round. Even a tank with armor as good as the M26 Pershing or Jumbo was still vulnerable to AT guns 75mm and larger, being able to flank that AT gun or strong point was more important than being able to slug it out in the long run. Without AT guns, enemy infantry had a very tough time with the Sherman, and even the Panzerfaust wasn’t all that effective unless used very close to the tank, and if the Shermans had infantry working with them and could hang back a bit, the Panzerfausts were much less effective.

In the Pacific, Shermans would really help defeat the Japanese and then be forgotten about, barely mentioned in most books on the PTO. You may not hear much about the M4 in the Pacific, but it saw a lot of action. A few of these Shermans are still out there, some rotting away in the surf for tourists to play about on, in Saipan, Tarawa, and I think Guam too. There’s still an M4A3 rotting away on Iwo Jima. The Japanese saw them as the most serious threat they would face and used some desperate tactics to kill them. Basically, the Japanese used man-powered mines and shaped charges, and or the largest caliber guns that could be aimed at the tanks. They also had a rare but effective 47mm AT gun as well. In many cases, just getting the tanks ashore killed a large number of them off with things like holes or shell craters in reefs.

Later production tanks with the improved large hatch hulls, in some cases would still have the 75mm gun turret, these tanks would all have final production turrets with loaders hatches and cast in improved cheek armor, or early turrets retrofitted with the armor and hatches.  Most of the large hatch hulls would have wet ammo racks, but a few large hull tanks, mostly M4A2 75mm tanks got the large hatches but standard ammo racks, with the add-on armor.

These large hatch welded hulls had a simplified one-piece front plate. It was now 2.5 inches thick at 47 degrees. The improved final drive (lower hull) housing offered 4.25 to 2 inches of armor. The rest of the hull armor thickness stayed the same, but it was not only stronger from being thicker, but many of the ballistic weak spots and welding joints were gone. Even these later large hatch hulls, only produced at three factories, have many minor cosmetic differences. The M4A1 received and improved large hatch casting, and its frontal armor and slope changed as well. It was 2.5 inches at 37 to 55 degrees and the rest of the hull remained the same thickness.

Many of these large hatch hulls had the larger and T23 turret. This turret had a 3.5-inch thick gun shield, a 2-inch rotor shield, and front armor of 3 inches. The sides were 2 inches thick and the rear 1, the top was also 1 inch thick. All these turrets had loaders hatches. They were also made from castings, just like the 75mm turrets.

Many tank divisions modified their tanks with add-on armor. The most common was sandbags. Many units came up with very elaborate steel frames welded to the hull to hold the sandbags in place. Even though army tests showed that sandbags did not help much, this was still popular. Patton banned their use in his 3rd Army. Another thing they came up with was adding a several inch thick layer, usually three to four, of concrete, to the front and sometimes the sides of the tank.  This armor was little better than the sandbags.

M4A3E2_54

There was a field armor upgrade that did work well; it was employed extensively by Patton’s 3rd Army. By this point in the war, late 44, early 45, there was an abundance of large hatch 75, and 76mm tanks in use. They would take the armor from knocked out tanks, often large hatch Shermans, and cut off the whole front plate, and weld it onto the front of an M4A3, A3E8, or even A1 tanks. They would also add an armored plate extended over the differential housing in many cases. They would also upgrade the turret armor by adding extra plates around on the turrets cheeks on 76mm turrets. One famous example of this upgrade package is General Creighton Abrams’s personal tank, an M4A3E8 76 tank, named Thunderbolt VII. This armor package was found to be almost as effective as the Jumbos armor and didn’t put as much strain on the tanks automotive bits as the sandbags and concrete. Steven Zaloga’s Armored Thunderbolt and Armored Attack books have extensive pictures of all the armor modifications and their use in action.

M4A3E8 with add-on armor plate.

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M4A3E8 with sandbags

sandbagged E8_zpsmjp5prjo

Jumbo with concrete

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Sources: Armored Thunderbolt by Zaloga, Yeide’s TD and two separate tank battalion books, Sherman by Hunnicutt,  Oscar Gilbert’s, Marine Tank Battles in the Pacific, WWII Armor, Ballistics and Gunnery by Bird and Livingston,  Son of a Sherman by Stansell and Laughlin, M4 Sherman tank at war by Green, Tanks are a Might Fine Thing by Stout, the  DOA Army Battle Casualties and Non Battle Deaths in WWII,  Another River, another town by Irwin, Tanks on the Beaches by Estes and Neiman, Cutthroats by Dick, 

#11 The Radios: The Sherman Tank Had Some Of The Most Advanced Radios In The World At The Time

The Radios: The M4 Tanks Radios Were Cutting Edge Technology For Their  Time, and Better Than German Tank Radios

turret rear
An SCR-528 Radio in turret bustle of an M4A3 76w HVSS tank.

US Army and Marine Radios

The Sherman tank came with an SCR-508, 528, or 538 radio set. Command tanks had an additional SCR 506 mounted in the right front sponson. This lets the tank listen on the net for the HQ they answered to while still talking to his own unit. The main radio set also had the tank intercom built into it.  This intercom allowed the crew to talk to each other, but not transmit on the radio, only the tank commander could do that, and as we will see, in a few cases he couldn’t either.

IMG_3076
An SCR-528 with the canvas dust cover installed and open.

Let’s talk about the radios, now that I know a little more about them.  The SCR-508, 528, and 538 were all in the same family. The TM covering these radios was TM 11-600 Radio Sets SCR-508-A, C, D, AM, CM, DM; SCR-528-A, C, D, AM, CM, DM; and AN/VRC-5 and it was very informative on how these radios worked. These radios were all FM band radios, used because FM radios deal with interference from the tank’s electrical system and motor better than AM radios. This did present a problem, in that the only radios the infantry or artillery used that could talk to the tanks were at battalion level since they were using AM Radios at the company level and lower.

SCR-508: This radio had the most options of the three basic radios that could come in a Sherman tank.  This radio set included a BC-604 Radio Transmitter, and two BC-603 Radio Receivers mounted on an FT-237 Mounting Tray. This gave the basic Sherman with this radio the ability to transmit on 10 FM channels, and listen on up to 20 if they had the crystals for all the channels. I’ve read a few things here and there that make me think they may have restricted how many frequency crystals could be carried, but that may have been just for the infantry. The BC-604 has a drawer with room for all the crystals for its frequency range. The frequency range was (Mc) 20 to 27.9.  This radio transmitter was 25 watts and had a range of 7 miles moving, and 10 to 15 while stopped. It could be powered by 12 or 24v dynamotors. This radio came in at 181 pounds. The tank’s intercom was also controlled through it, and BC-606 Interphone Control Boxes mounted at each crew station.  These radios would be found in platoon leaders and company commander’s tanks.

SCR-508_Data
SCR-508 Data Sheet

SCR-528: This radio was exactly the same thing as the 508, but with one less BC-603 Receiver. In most cases the spot where the 603 would have been was taken up by a CH-264 Parts Chest. A 508 could be turned into a 538 or the other way very easily. This radio would normally be the radio installed in the standard gun tanks of the platoon and company. This Radio came in at 181 pounds, and the same specifications other than only having one receiver.

SCR-528_Data
SCR-528 Data Sheet

SCR-538: This radio would only be installed in tanks when there was a shortage of 508 or 528 at the factory or in a battalion itself.  This radio did have one feature that set it aside from the ones above because it lacked a transmitter, it needed a BC-605 Interphone Amp for the crew intercom system. This one came in at only 135 pounds.

Data Sheet for SCR-538
Data Sheet for SCR-538

SCR-506: This radio would be the rarest of radios installed in Shermans. This “Command Tank” radio would only be installed in the battalion commander’s tank. On early small hatch Shermans, this radio would have taken up some ammo space in the right sponson near the BOG. In later large hatch wet tanks, they lost some .30 cal storage. It could be operated either on 12 volts or 24 and was designed for vehicle use. It would only be able to talk to Battalion level HQs and higher, and the tanks’ normal radio, probably in most cases an SCR-508, would be used to talk to the tanks in the battalion. This radio could have four preset frequencies, and also an adjustable range from 2-4.5(Mc) transmitting, and 2-6 (Mc) receiving. This radio was hefty and came in at 176 pounds. It was made up of the BC-652 Receiver, BC-653 Transmitter, and the FT-253 Rack Mount.

Data Sheet for the SCR-506
Data Sheet for the SCR-506
USWWIIM1938andM1Helmets2
US Army M1938 tanker helmet, along with an M1 steel helmet, also the intercom control box and throat mikes are seen on the left, along with the headphones in the tanker helmet’s ear covers. The Steel pot helmet was often worn over the Tanker Helmet. Photo Source: Mike Roof.
USWWIIM1SteelHelmets1
This image shows the Sherman tanks intercom gear adapted to the steel helmet M1. It also shows an M6 periscope and an odd microphone I’m not familiar with. Photo Source: Mike Roof.  Photo Source: Mike Roof.

Here’s a Video of an SCR-508 the has been restored in use.

Here’s a Video of an SCR-506 that has been restored in use.

. . .

Destruction of these Radios would be top-priority for the crew if they had to abandon a disabled tank. After watching videos of restored versions of all these radios, I have to say the biggest surprise is all the mechanical noise as they warm-up or transmit. It was also a surprise at how clear the voice was on a 508 in good working order. After reading through the manual for the 508 it is clear, these old radios needed a lot of work to keep them operating. There is a long list of things that have to be inspected, cleaned, and lubricated to keep the thing working. These radios all used tubes, and those tubes, (much like a little lightbulb, if you have no idea what one looks like), also had been removed, and inspected, and cleaned. These tasks would all add to the daily grind of being a tanker and keeping the steel monster working.

Radios used in Commonwealth and Lend Lease Shermans

VC-WirelessBustle-2
a Wireless Set Number 19 in a Sherman tank.

When the British took possession of a Sherman they installed the British Wireless Set Number 19, and it replaced the intercom system as well. It was designed by the British Company Pye Ltd. It was slightly smaller than the US radios. At the level these radios were on, I doubt a British Sherman and an American Sherman could talk to each other. These Radios were made in the USA by RCA and installed in tanks slated for Lend-Lease use.

These Radio sets were both more advanced, and less advanced than their US Counterpart, A true Transceiver, the first, meaning the receiver and transmitter were part of the same unit and shared circuitry. They used UHF for short-range direct view tank to tank communications and the HF portion could transmit up to 50 miles. These radios were not on the same frequency ranges as the US Army, and they were not as suitable for vehicle use. They were cheaper and simpler to build though and they were powerful Transceiver.

wireless
Another Wireless Set Number 19 in a Sherman, this one with Wire Guards.

The WS19 set had three systems. The A portion was a High-Frequency radio transceiver with a range of up to 50 miles. The B Portion was a Very High-Frequency transceiver for short-range, line of sight communications up to a mile. The final part was an audio amplifier for the crew intercom system. It had control boxes mounted at each crew station just like US tanks.

CanadianWWIITankerEquipment

Photo Source: Mike Roof.

Frequency range:

A setMkI: 2.5 – 6.25 MegaHertz (MHz), MkII & III: 2 – 8 MHz

B set – 229 – 241MHz

Modulation modes:

A set: Amplitude Modulation (AM) for speech, Continuous Wave (CW)

and Modulated Continuous Wave (MCW) for Morse code transmission.

B-set: AM speech only

Approx Power output: A-set: AM & MCW 1-3 Watts (W); CW 3-5W, B-set: 0.4W

Number of valves: 15 thermionic valves (termed tubes in the USA)

Size/weight: WS19 17.5×8.5×12.5 inches – 40lbs,Power Supply Unit 6×8.5×12.5 inches – 25lbs

Aerial Variometer 10×5 inches cylinder – 5lbs

Power Supply: 12 Volt (V) or 24V lead-acid batteries driving rotary motor-generators,

which provide 275V at 120 milliAmps (mA) for the receiver and 500V at

50mA for the transmitter.

Here’s a video of a Wireless Set Number 19 in use after restoration.

. . .

Sherman Radios in use:

Here is a fascinating transcript of a marine tank company’s radio chatter, taken by a US destroyer offshore during the fighting on Okinawa. You can find this on page 64 of Michael Greens M4 Sherman at War.

Troops_and_M4_Sherman_tanks_of_10th_Army_advancing_on_Okinawa

“This is Red Two, Red One; heartburn says that he is ready to start shooting at those pillboxes”

“Tell Heartburn I can’t receive him. You will have to relay. Tell him to give us a signal and well spot for him”

“Red Two wilco”

“Heartburn, raise your fire. You’re firing right into us”

“That’s not Heartburn, Red Two, That’s a high-velocity gun from our left rear. I heard it whistle. Red One out.”

“Red Three, this is Red One. Can you see that gun that’s shooting into us?”

“Red One, I think that’s our own gunfire.”

“Goddamnit, it’s not, I tell you. It’s a high-velocity gun and not a howitzer. Investigate or there on your left. But watch out for infantry; they’re right in there somewhere”

“Red Two, tell Heartburn down fifty, left fifty”

“Red Two wilco”

“Red Three, what are you doing? Go southwest!”

“I’m heading southwest Red One.”

“For Christ’s sake, get oriented. I can see you, Red Three. You are heading northwest. Fox Love with hard-left brake. Cross the road and go back up behind that house”

“But”

“I don’t know why I bother with you, Red Three. Yellow One, take charge of Red Three and get him squared away. And get that gun; it’s too close.”

“Red One from Red Two, Heartburn wants to know if we are the front lines”

“Christ yes we’re plenty front right now”

“This is Red Two, artillery on the way”

“Red one wilco”

“Red One from Yellow One. I can see some Japs setting up a machine gun about 100 yards to my right”

“Those are our troops Yellow One, don’t shoot in there”

“The man at my telephone –  I think he’s an Officer, – says we have no troops in there.”

“Yellow Two, go over there and investigate. Don’t shoot at them; that man at the telephone probably doesn’t know where the troops are. If they’re Japs, run them over.”

“Yellow One, wilco.”

“Go ahead, Yellow Two. What in God’s name are you waiting for?”

“I’m up as far as I can go and still depress my machine guns.”

“The hell with your machine guns! I told you to run over them! Run over them, Goddamnit; obey your orders!”

“Yellow Two, wilco”

“Yellow One, what have you to report on that machine gun?”

“Red One, a Jap stood up and threw a grenade at us so I gave him a squirt.”

“Did you run over that gun like I told you?”

“No. Red One, we put an HE into it and wrecked it.”

“Christ, won’t you people ever learn to conserve your ammunition…”

“Red One from Green Two, I’m stuck between two trees.”

“Green Three stand by him. After the infantry has cleared up around there, get your assistant driver out and tow him clear.”

“Green Three, wilco”

“While you’re waiting, Green three, keep an eye out on that house on your right. I see troops coming out of there with bottles in their shirts.”

“Can I send my assistant driver over to investigate?”

“Stay in your tank”

“Yellow One, from Red Three, where are you going?”

“Red One from Green Four. I am moving out to take out a pillbox the infantry pointed out I will I will take care of it and let them catch up.”

“Where is it, Green Four?”

“In that clump of bushes to my right.”

“Can you see it? It is all right to fire? Wait Green four”

“Green Four wilco”

“Green Four, you better not fire. The 4th Marines are over there somewhere.”

“Run up on the box and turn around on it”

“It’s one of those coconut log things. It looks like it may be too strong to squash. Is it all right if I fire into the slit?”

“Affirmative, but be careful, wilco”

“Red One, this is Hairless. We’ve got some Japs bottled up in two caves in Target Area Four Baker. We’d like you to leave two tanks to watch them.”

“You know damn well that’s infantry work. We’re a mobile outfit, not watchdogs. Put your saki drinkers in there.”

“Ok Harry, Red One out.”

“All tanks start ‘em up. Move out now. Guide right and form a shallow right echelon. As soon as we hit the flat ground around the airfield, spread out to one hundred and fifty-yard interval. Alright, move out, move out

. . .

The fighting on Okinawa was brutal and they lost a lot of tanks. There were Army and Marine tankers there, all operating Shermans, mostly M4A3s, but a few late model M4A2s were mixed in with the Marines. I thought it was very interesting how much they talked about what they wanted to shoot, and how they had to rely on each other to confirm if a target was friendly or not.

I also thought it was amusing when Green Three asked if he could send his assistant driver to check out the log bunker. I really suspect it was sarcasm. The tankers seemed reluctant to run over the Japanese out in the open. Was it because getting in that close was dangerous, or because cleaning people out of the treads after the fight was really gross? Morbid questions aside, being a tanker in the Pacific had its own share of risks, and took men with a lot of guts, and stamina.  Many of the fights took place in very warm locations, and late in the war, colder ones. The Japanese willingness to throw away their lives made being a tanker a dangerous place,  but if it followed the same pattern casualties in the ETO did, then being an infantryman was by far the most dangerous thing you could be.

The website www.radionerds.com was a huge help with this post. Not only do they host a lot of info on Radios, but they have the manuals, datasheets, and pictures to go with them. They also have a whole site dedicated to the Army’s amusing PS Magazines. Please check them out!

Sources: Armored Thunderbolt by Zaloga,  Sherman by Hunnicutt, Combat Lessons, The Rank and file, what they do and how they are doing it 1-7, and 9.  The Radionerds website  TM11-67

#10 Tank Infantry Communication: They Couldn’t At First, Shocking But True!

Tank Infantry Communication: That’s Right, Tanks, and Infantry radios Did Not Talk to Each Other!

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The only decent image I could find of the phone on a tank( I found more)

M4 tanks and US Armor, in general, couldn’t talk to the infantry they were tasked to support. When I first read about the communication problems between tankers, and the ‘doughs’ they were fighting with I was surprised. It’s hard to believe in today’s world; talking to people inside a vehicle right next to you would be a problem, like send a text right bro? Well not back in the forties, they did have two-way radios, but the technology used vacuum tubes, because transistors had not been invented, and they were not very reliable and had a limited number of radio frequencies they could talk on. They also had the problem that tank radios and infantry radios did not share frequencies or even band!

M4_Sherman_Tank_30_96th_Division_Big_Apple_Ridge_Battle_1945_Okinawa
This M4 Composite hull supporting the 96th ID on Okinawa has an infantry phone, and there is Dough on it.

So Shermans would be sent to support Infantry, usually, a separate tank battalion would send a platoon over to regiment of infantry, often the battalion would be assigned to the same infantry division for a long period of time so they could get used to working with the same people. This helped, but in combat, they still had real communication problems, no matter how long they had worked together in training. This problem didn’t really come to the top until after D-Day when the Sherman was supporting infantry in the bocage country, and close cooperation was needed. A platoon could be broken down further to support smaller units as well, and it wasn’t unheard of for a single tank to support a company, though they really tried to at least keep tanks paired up.

Things would normally go well communication-wise before the shooting started; at least the tank commander would be riding with his head stuck out; so he could talk to the infantry riding on his tank or walking around it. A savvy infantry officer may be on the tank talking to the commander. Once the tank started taking enough fire for the crew to close those hatches, everything changed. No amount of yelling or even banging on the tank would get the crew’s attention. Since the tanks and infantry were not on the same radio nets, if they wanted to get orders to the tank through the radio, they had to radio up to battalion or regiment level, get someone to find the tank battalion commander or someone who could talk to the tank on the radio, and then hope, they could get that actual tank on the net during the firefight. This did not work well. Often it took a man standing in front of the tank and waving his arms to get them to open up, this clearly was not an ideal solution either, and even when the commander did pop his head out, he had a very hard time hearing anything with his helmet on.

If the tank unit and infantry units got to train together and had been working together for a long time, this was less of a problem than a tank battalion assigned to a new infantry division with no combat time and little tank/infantry training. This lack of combination became a clear and prominent problem in the bocage fighting in Normandy when infantry wouldn’t be able to warn the tank they were working with of an imminent threat in a timely manner. The infantry would often be forced to fall back from the tanks leaving them alone, and easy targets for enemy infantry close assaults.

Various solutions were improvised in the field; they tried using the infantry’s handy talky from inside the tank, but the tank’s electrical system caused too much interference. They also tried giving company level infantry headquarters spare tank radios, mounted to a backboard, but they were really too heavy to be practical, and not common enough to be all that useful. Some smart tanker figured out if you poked the handy talkie’s antennae out of the hatch, it worked, and that was the best solution for a little while. They also tried rigging up field telephones, with spools on the back of the tanks to let out the phone wire as they advanced, but the wire broke easily and restricted how the tank could move.

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The best solution was worked out by Operation Cobra, and many tanks went into combat sporting it. The fix was mounting an EE-8 field telephone in a .30 caliber ammo box on the back of the tank. This phone was wired into the tanks intercom so anyone could walk up and say, “Hey! You blind Sonsobitches!! Shoot the machine gun nest over to the right, that house you’re shooting up is empty, you stupid bastards!!” or something to that effect. This, of course, could get the infantry guy, who wanted to talk to the tank shot, since he had to stand up behind the tank, but they still haven’t come up with something better, and M1A2 Abrams tanks are getting infantry phones installed on them now.

The Marines came up with this solution as well, but faster since they used the M4 for much less time than the Army. They did come up with it around the same time as well, in July of 44. They found it essential for working in close with the fellow marines. The Japanese at this point was using man-powered shaped charges on a pole, or magnetic mines, and the tanks really depended on the infantry around them to be their eyes. Marine tanks operated buttoned up once the shooting started, without the phone, they were much less effective.

Sources: Armored Thunderbolt by Zaloga, Yeide’s TD and two separate tank battalion books, Sherman by Hunnicutt, Combat Lessons, The Rank and file, what they do and how they are doing it 1-7, and 9.  Oscar Gilbert’s, Marine Tank Battles in the Pacific,  Son of a Sherman by Stansell and Laughlin, M4 Sherman tank at war by Green,  the Lone Sentry,

#9 The Crew And Their Stations: The Human Part Of The Tank, How They Lived, Worked, And Fought

The Life of a Sherman Tanker: The Crew the Tank, and How They Lived With it,  Babied it, Loved and Hated it. 

This section is about the crews and their life in the Sherman tank. It will cover the responsibilities of each crew member. It will try and cover the day-to-day routine of a tank crewmember. No man facing war in the modern world has it easy, and the men who fought the Sherman fit this category, but the claims of bad writers aside, the crews of Sherman tanks had a better chance to make it through the war than your average dough. Tankers faced dangers regular infantry didn’t, but overall, being a tanker was more comfortable, safe, and less likely to get you killed than being a grunt. No man who had to face down Nazi Germany, or Imperial Japan, had it easy.

M4A3(76) 31st Tank Battalion 7th Armored Division

In most cases the crews loved their tank, this point was really driven home in a recent Chieftain’s hatch, he mentioned how he was interviewing an American tank crewman from WWII, and the crewmember loved the Sherman because it protected him from all the stuff he saw kill the infantry around his tank.  When any kind of artillery fire comes in, the tankers can just close their hatches, buttoning the tank up, and wait it out.  The exterior cargo on the tank is going to get some holes but the crew was safe, and even a direct hit, unless it was a really big gun, probably wouldn’t hurt the crew.  The doughs around the tank had to find any cover they could, and lots of infantry died to mortar and artillery fire.  The tankers also didn’t have to worry about machine guns, AP mines, grenades, and bayonets either.

Being a tanker has its own set of dangers and horrible ways to die, but overall, it was a lot safer to be in a tank, than to be any kind of grunt. Sure, the beast you live with, service, and fight can hurt or kill you if you are not careful, ripping off a carelessly placed foot as a turret rotates or losing fingers to hatches can suck, but training can minimize those, no training can save you from an artillery barrage as grunt if you didn’t have time to dig a hole and it’s flat.  The gruesome ways tankers could die in combat are somewhat offset by the things he can stash in the tank to make life more comfortable. Booze and non-army food were popular items for tanks, plus, you’re not walking around with a heavy pack all the time.  

Drills: Monotonous Training, because ‘Second Nature’ means it’s easier to do under fire!

Along with the Technical Manuals that the crew received on the radios, guns, tracks and suspension, and more, there were Field Manuals that the crew used to drill on the tank. The main one for the M4 gun tanks was FM17-67 Crew Drill and Service of the Piece, Medium Tank M4. This was a 132-page book that contained instructions on the crew composition, and on foot formations, crew control, drills, serving of the piece, mounted action, dismounted action, removing wounded from the tank, inspections, sight adjustments, and destruction of the tank and its components. Training means practicing these things over and over.

The idea behind the Field Manual was to give the tank commanders and platoon leaders a set of standard instructions to teach their men so they were all trained to do their jobs the same way, to make everything about the tank and using it as familiar as possible, so it could be used in combat effectively, even under the most terrifying conditions, and still accomplish its mission.  The commands being standardized meant the crew members could be moved around and know the standard way things are done, even in another tank, with an unfamiliar crew.

Now let’s talk about what drilling is all about, because unless you’ve been in the military (I haven’t been, but you can learn about this stuff without having served, and that’s the idea here), you may not really know what drilling means, and it doesn’t involve power tools. Sportspeople will have some idea, drilling on something is doing it so often, exactly the same each time, hundreds of times or more, to make the drill second nature. So when a tank commander yells abandon tank, no one thinks about it, they just do it, and they’ve done it so many times, they do it flawlessly and fast because they practiced over and over knowing their lives could depend on it later.

Here’s a list of some of the drills: Do Something Over and Over until it bores you to Tears

Each of the drills would be called out by the commander as a verbal order, and each crew member including the commander would carry out a series of actions to accomplish the order. For example, Drill/Order Dismount would be called out, each crew member would have specific instructions for what they were expected to do. Starting with disconnecting their headset intercom cable, then standing on the seat and climbing out, the open hatches order would already have been given.

Prepare to mount the Medium tank; Mount/Dismount: The order/drill for getting in or out of the tank.

Close all doors/hatches open Doors/hatches: The order/drill for Opening or close the hatches on the tank.

Prepare to dismount through escape hatch; DismountThe order/drill for the whole crew prepares to leave the tank through the belly escape hatch.

Pep Drill: A drill, made by making a series of drills into a command to be carried out. for example, Commander orders; IN FRONT OF YOUR TANKS, FALL IN; MOUNT; DISMOUNT; FALLOUT SERGEANT; ON THE LEFT OF YOUR TANKS, FALL IN; FORWARD, MARCH; TO THE REAR, MARCH; MOUNT.

Prepare to fire; Various Fire orders: The orders for shooting the guns at various things, including the main gun AA gun and CO-AX.

Secure Guns:  This was all the actions taken to secure the guns, including unloading them and lowering the periscopes.

Restow Ammo:  This order/drill was for re-stowing the hard to reach ammo so the loader could reach it better by restocking the ready racks and racks nearest him that were depleted by firing.

Load Ammunition: This is the command/drill for loading the tank up with fresh ammo through the hatches.  Main Ammo came in 2, and 3 round crates or tubes, so the crew would have to unpack it all then load it into the tank.

Prepare to fight on Foot; Dismount: This is the order/drill for the crew to get their personal weapons ready, and prepare to exit the tank and fight on foot.

Out of Action: This is the order/drill to get back in the tank after fighting on foot.

Engine FireThis is the order/drill for what to do when the tank’s engine is on fire.

Air Horn Fire: This one is similar to the one above, but for a specific type of fire that only happened on the tanks powered by the R975.

Perform halt inspection: This is the drill/order for doing all the inspections involved with maintaining the tank on a road march.

This list is just a sample, there are many more in the crew drill manuals, and the drills vary a little depending on the vehicle. There were a series of drills specific to the various models of Sherman I didn’t list along with numerous inspections related and maintenance related drills too. If there was a common action or job to do on a Sherman tank, there was a Drill involving it. Once in a combat theater drilling would be a lot less common, unless they were refitting and training a lot of replacements or in a rear area for a long period of time. 

Inspections drills involved inspecting parts for wear and tear, and were not the same type of inspection officers would carry out to makes sure all men and gear were present and working.  There would be those as well, but they are not really a drill.

Another responsibility of the crew that was covered in FM17-67 is destroying the tank if it is disabled in an area likely to fall into enemy hands. If they had a good chance of escaping capture, they were to take the periscopic and telescopic sights, if not they were to be smashed.  Then basically, what was destroyed was based on what you had the most time to do. If you had very little time to get away, you might only disable the main gun, machine guns, and stabilizer, with more time the gun recoil mechanism and or the whole tank. The manual gives instruction on methods to destroy everything from the machine guns and main gun to the tank itself.  The Army has refined this over the years, and now the tanks have charges just for destroying them as part of the tanks gear.      

Now let’s go over each man of a Sherman crew and the things he was responsible for and what his job involved.

Commanders position: The Boss, the Man in Charge, the Big Cheese

comand2

The commander sat in the back right side of the turret directly behind the gunner. His job was to command the tank. This meant he took the orders from the platoon leader or company commander and made his tank perform the tasks he’d been given to accomplish the missions he was on. He had the radio in the bustle of the turret to his rear to help him communicate with the rest of the tanks in his unit. To do this he could stand on his seat with his head and shoulders out of the tank, and direct the crew over the intercom. Only he could transmit on the radio, but the other members of the crew could listen. They could all talk to each other on the intercom. On early M4s, when ‘buttoned up’ or when the tank was all closed up with its hatches closed, the commander only had his rotating copula periscope. Later versions of the Sherman had an all-around vision cupola, discussed earlier, that provided a much better view around the tank for the commander. As some of the charts show in the data section, this was the most dangerous crew station. The commander spent a lot of time with his head stuck out, when the rest of the crew was buttoned up, it made him a prime target for basically anyone and anything being shot at the tank.

His job in combat was to call out directions to the driver and call out targets for the gunner. He had a sight vane mounted on the roof of the turret to use outside, by using it and his turret override; he could put the gunner roughly on target by rotating the turret. If he was the platoon leader or company commander, he would be calling out directions to the other tanks and trying to sort out what everyone was doing and keep things under control, or in the company commander’s case as much control as he could over the tanks in his company. He would be depending heavily on the platoon commanders to run their platoons and keep him informed of what was going on.

He was responsible for the tank up to a point and had to make sure the crew kept up on all the required maintenance to keep the tank in proper running order. He was also responsible for the well-being of his crew. The commander was for obvious reasons, the most experienced man in the tank in most cases, as well. Crews that had that belonged to the platoon, company, and battalion commanders were often short a man on tank maintenance since the officer would be off doing officer stuff, like planning and thinking, sometimes the tanks had a sergeant who stood in for the officer when he wasn’t using the tank as well.

The commander’s position was the only spot open to officers under normal operations.  The most common officers would be 2nd lieutenants, and lieutenants as platoon leaders, captains as company commanders, and lieutenant colonels as battalion commanders. You might find a major or two in there as well. NCOs of various ranks from the lowly buck sergeant to staff sergeants and maybe higher on rare occasions would be the enlisted side of the tank commander scale. All the other positions in the tank were filled with lower ranking NCOs or PFCs.

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M4 Commander and his cute puppy crew!

Gunner: The Man behind the gun Big Gun and the Co-Ax.

The gunner was usually the next senior man in the tank. He sat right in front of the commander and used the commander’s hatch to get in and out. He had his own set of turret controls, and only he could control the elevation of the main gun. Along with the gun controls, he had all the controls for the stabilizer in front of him.  In early Shermans, he only had a periscope with a reticle, it had a fixed 6x power zoom, but also could be looked through with no zoom. Later gunners had the periscopes and a direct view scope. He was dependent on the commander to get him near a target and then took five to six seconds for him to pick up the target. This took a much longer time on German tanks like the Panther, with gunner target acquisition times in the minutes, not seconds.

gunnerandcommandrgunners spot

The gunner controlled the main gun, and the coaxial mounted M1919A4.30 caliber machine gun, though he was still following the commander’s orders on what to shoot. Each weapon was fired with a footswitch on the gunner’s footrest, and a manual lanyard for backup use. The gunner controlled the turret either with a hydraulic system independent of the tank’s motor, and a manual system that just used a crank and gears. You would think the gunner would have the best view out, but in tanks, most of the time, at least in the older models, their view was very limited, but for the era, the Sherman was better than most other tanks. A good gunner working with a good loader in the 75mm armed Sherman could get off, two or three aimed shots in a very short time, a very big advantage in tank combat.

GUnners periscopeII

A Tank gunner also had to be able to shoot, like all other WWII tanks, the Sherman lacked any kind of aiming aid for the gunner other than his scope and periscope. Limited range finding could be done with the reticle in the sight, based on the known height of something, but it was not very exact.  The gunner’s brain was really the tool that did the correcting based on experience, skill, and innate ability and feedback from the commander on fall. Modern tankers have it much easier in this area, since modern tanks have laser rangefinders, and sensors to check for windage, temperature, and barrel wear, and a computer to use all the data to compute the aiming corrections for the gun. That was something that probably couldn’t even be dreamed of by a WWII tanker. Better rangefinders were right over the horizon though.

M4A4 Armament diagram westinghouse traverse 75mm early turret
This is the all-electric Westinghouse Turret drive, the least popular of the three units used.

Loader: The Man Who Feeds the Hungry Beast!

The loader’s job was to service the 75mm M3 gun and the coax .30 caliber machine gun. The commander or gunner would call out the ammo type for the main gun, and the loader would load the gun and yell “Up!” and the gunner would know the gun was ready to fire. The loader was supposed to watch the belt on the coax and make sure the gun didn’t run dry. He was also supposed to be trained on how to clear a problem with the main gun or machine guns. Even canons can have duds, or shell problems, or even just break.  There were a small number of spare parts kept in the tank for the common things that failed on the guns.

Sherman-Easy-8-tank-interior-02loader

loader2

The loaders station was on the left of the gun, opposite of the gunner. He had a lot of space to move around compared to other tanks of the time, and a fold-up seat. He also had a fully rotating periscope on the roof above him for his viewing pleasure.  In early Shermans, the loader had twelve ready rounds around the base of the turret basket, with another eight in a ready rack at his feet. This was the primary reason so many early Shermans burned, anything that penetrated the turret or the hull and hit those exposed rounds would set off a chain reaction of the propellant in all the ready rounds igniting, destroying the tank, and often killing most of the crew. This problem was figured out pretty fast and the twelve exposed rounds were deleted and an armored four-round ready rack replaced it and an eight-round ready rack was used on improved models. Later armor was added to the inside and outside of the sponson ammo boxes as well, before removing them completely for the wet ammo installations in later improved hulls floor.

co ax moun 75mm turret

If a lot of firing was taking place, the loader was a very busy guy, on early Shermans the sponson racks, even without all the turret ready ammo, he had a fair number of easy to get to ammo racks for the main gun, but since the turret basket was screened, he could only get to them with the turret at certain bearings. With the switch to all ammo but the ready ammo in the floor of the hull, his job got much harder. On the wet ammo rack tanks, he would have to pull open doors in the bottom of the turret basket, then open an armored box and pull ammo from it. He had to know what was in all the ammo boxes, and was responsible for what got loaded into where, and remembering it all.

M4A4 small hatch storage

The loader on some models also had a 2-inch smoke mortar to load and fire at the commander’s desire. It was a short-lived feature. It protruded into the loader space and was not well-liked by that member of the crew.  Part of the crew drills for the Sherman involved almost the whole crew, during combat, if the tank wasn’t moving, the co-driver and driver helped the loader by handing him ammo from harder to reach ammo racks near them, and in lulls, in the fighting, the whole crew would help, so the loader could re-arrange the ammo racks getting hard to reach ammo into the easier to reach racks.

After spending some time as a co-driver, a crewmember may be moved up to loader. A good loader was important, the 75mm and later 76mm guns were capable of very fast rates of fire, but only if the loader could keep up. When he wasn’t scrambling around the floor of the turret opening armored doors in the floor to find ammo to feed the gun, he was another set of eyes. On early tanks using his periscope, on later ones he could stick his head out of his own hatch. Many crews mounted extra machine guns to the roofs too, and if there was one on the loaders hatch it would be his to shoot. Some units would put the M2 .50 mount in front of the loader, and put a .30 Cal M1919A4 on a mount in front of the commander.

Early to well into later production 75mm gun, armed Shermans did not have a loaders hatch. This meant if the loader had to bail out of the turret through the commander’s hatch, he had to get around the main gun to do it. It would be a very hard thing to do if the tank was burning or the loader was wounded and the tank filled with smoke, but that’s why they drilled so much.

The Driver: The Man Who Drives But At the Behest of the Boss

The driver and co-driver were separate from the turret crew; they sat in the forward part of the hull. They could only climb into the turret if the turret was rotated to line up the holes in the turret basket, at least on early models, with the driver’s compartment. The transmission sat between the driver and co-driver and only the driver had a set of controls. Only the driver had any instruments as well. On early tanks, the drivers and co-drivers hatches were oval-shaped and small and required the man to twist sideways to get through. On very early tanks the driver had a rotating periscope in his hatch and a direct viewport with an armored cover. The viewports were removed from production and extra armor was added over them. This was done very quickly at most factories when it was found bullet splash could get through even a closed port. They were also a big ballistic weak spot in the armor.

drivers and co driversdrivers

The driver needed to be able to drive the tank, often without knowing what he was driving into, trusting the eyes of the other crew members and commander to keep him out of trouble. He needed to know what his tank could drive over and climb, and what it couldn’t. Getting your tank stuck in the mud was an embarrassing thing to do. If the tank was really stuck, it might require more than one tank to pull it out, if the resources in your platoon couldn’t do it, you had to call in other help. The crew would get a lot of heat for that type of thing.

M4A4 drivers control group

Driving the tank was important, and the driver had to work well with the commander. A savvy co-driver could be moved into this spot, or a good loader would be given a shot. The position was roomy and fairly comfortable as tank positions go. He had a good view forward from a fixed periscope and rotating one built into the driver’s hatch. The seat could also be adjusted up, and the tank driven with the driver’s head stuck out. In the movie Tank with James Garner, you get a lot of shots of him driving the tank with his head stuck out a small hatch M4A3.

M4A3 drivers hatchm4a3 compass

As tanks go the Sherman was reputed to be pretty easy to drive, the R975 powered models the hardest, the GAA the easiest, with the diesel and A57 powered models being almost as good as the GAA when in fine working order. Learning to drive the Sherman was the easy part, where and how to drive it in combat and just over what terrain it could go that was the real challenge.  The Sherman tank’s mechanical toughness made it easier for the driver to worry about the important parts of t his job and not breaking the tank.

M4A4 instrament panel keyfor M4A4 instrament panel

blower for the crew
Air blower for the crew mounted  between the driver and co-driver, not the light mounted on it

The Co-driver: The BOG, the Low Man On The Pole

The co-drivers position was on the right front of the hull and has its own hatch. The position had no controls or instrument panel. This position had a .30 caliber M1919A4 machine gun, aimed by tracer through the periscopes. This gun had a very limited fire arc and wasn’t very effective, but the extra crew member was nice to have around to help keep the tank up and running.

M4A4 BOG DV Tank from TMdriver and co drivers seats

This was the position most new tankers started in. As they learned how the tank worked they got moved around. Not all crew changes were due to losses. You could have a man transfer out or be sent to the rear for a disciplinary situation, to leave, or some other reason. Crew members could be moved from tank to tank. If another Sherman lost its commander and no one in it was ready to replace the man, a really good gunner or driver might get pulled out of another tank to take it over. Crews were kept together for as long as practical. The co-driver was the closest to the escape hatch built into the floor of the tank; it was right behind the seat and would be the best way for the driver and co-driver to get out of the tank in some cases, or the only way if the turret was in the wrong place.

machineGunner

The BOG would be ready to help the loader re-store ammo when needed in combat or would be the crew member the commander asked to get out and check something. On command tanks, he would have an extra command radio mounted in the sponson next to him and he would assist the commander in its use.

Living with the Beast: In the Field, the Tank was Home

The five men of the crew were responsible for keeping the tank running. This meant keeping up on a long list of daily chores from checking track tension and adjusting it, to tightening the bolts on each end link on both sides of the track run, to checking the oil and radiator fluids, or the batteries. There were also numerous things that had to be hit with a grease gun, others that had to be adjusted. Depending on the motor type various engine maintenance tasks had to be done, and they all needed their air cleaners cleaned often. Plus cleaning and maintaining the main gun, and all the machine guns, loading ammo and fuel. The radios would require constant attention to keep working reliably. That’s just how everyone’s radios were, and US Radios were better than most.

Lube chart for M4A3
The lubrication chart for the M4A3 is just one page. There was another for the mechanical stuff that wasn’t related to the powertrain or motor too.

Getting food and eating, and other person chores all had to be done as well, and sometimes the crews ate while they worked on the tank. Many tanks ended up piled with extra gear to help make the tanker’s lives easier. They only had to keep the tank up to a point, if it needed major work, like a new transmission or engine; a company or battalion level maintenance crew would come and help, ideally, or a replacement tank would be issued if too much work was needed.

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Fort Knox Barracks Building Circa 1972.
Typical WWII barracks, this one at Fort Knox.
The inside of the Fort Knox Barracks above.

Daily life at a major base or rear area base in a combat theater would be similar to the infantry or the other combat arms. On a major base, they would be living in heated barracks, their tanks in a tank park somewhere, with an area set aside for maintenance. They would be living in barracks organized the same way as their units, though if in the US some men could be living off base. There would be mess halls and bathrooms with plumbing and hot water. Daily life would be drilling, cleaning and maintaining the tanks, drilling on the tanks. Practicing on the tanks, driving it around, using the weapons, fixing it when it broke, or getting it unstuck when it got stuck. Generally learning how the tank worked and how to use it, with field training and bigger exercises mixed in. There would also be a lot of cleaning, the tank, the barracks, the area around the barracks, and probably KP duty and other watches or duties.  Tanker probably didn’t spend as much time running or doing calisthenics as the infantry either.  One of the most common training drills would be getting in and out of the tank fast under various circumstances.

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Another picture of Fort Knox Barracks, this one from much later. Hmmm, odd-looking soldiers…

In a combat theatre rear area, life would be like a stateside base with more tents, and fewer amenities, and worse food. They would also be spending more time training on the tanks and later in the war, training with the infantry they would be working with. They would be spending their time training new people or replacements, and getting ready for their first combat or going back in combat.

US_3rd_Armored_Division_M4_Sherman_Tanks_in_Action_in_Belgium_1944
M4A1 and M4 tanks loaded with a lot of stuff on the back deck. Extra food and ammo were common fare, along with things to make life a little easier.

Once out operating things would be different, though much time would still be spent not fighting, working on the tanks, eating, and generally being bored. The living conditions would be worse, the men would be sleeping under tarps hung from the sides of the tanks as makeshift tents, and sleeping on the ground or another tarp on the ground or cots if they could steal them somewhere and they didn’t get shot up while fighting, since they would be tied down somewhere on the outside of the tank. Once free of the daily grind that base life was, free from junk on the bunk, or tarp in the tank inspections, tanks start to look more like something out of the movie Mad Max than tanks from a military unit. Tankers collected all manner of junk to haul on their tank, logs were common, maybe for the added stand-off armor value against AT sticks, or for the value in getting the tank unstuck from the deep mud. It was really up to the officers and senior NCOs to stay on top of the crews to keep the tanks in running condition, and it was common in badly run units for daily maintenance to stop on the tanks once the fight started.

us armor in ww2

Tank crews like any other soldiers look for things to make their life easier when stuck out in the field and at war. Tankers have the advantage of being able to stuff things in the nooks and crannies of the tank, or just strap it on the outside. Things including extra food, and small arms ammo, water, gas and oil cans, stuff pilfered from abandoned homes or occupied ones once the Army made it into Germany. It’s really no surprise the US Army liberated goods from the Germans, after having to fight them and seeing what they did in the camps, it seems no one really cared as long as US Soldiers didn’t shoot the Germans while taking their things.  Tankers could haul a lot more loot than an infantry grunt could. I will not judge allied troops for taking things from the Germans; the Germans did a lot of stealing themselves, and most stood by while the Gestapo shipped 12 million people off to their deaths, so having their stuff, often stolen property itself, taken by troops who didn’t want to be there in the first place doesn’t bother me. It surprises me the Allies didn’t slaughter more Germans outright after seeing their ghastly inhuman crimes though.

Another key difference is, in anything but the most desperate situation, Army or Marine Corps tanks withdrew to the rear, not far, but far enough to not be in the line, at night. Tanks are blind during the day, at night they are almost cripplingly so and tanks were rarely used in night attacks, no countries experimental night vision systems were good enough for that. Holding the line was left to the grunts, at night the tanks would spend their time getting their tanks reloaded, refueled, and repair any damage, on top of all the normal day to day maintenance a tank still required. This was done before eating, and sometimes under harassing artillery fire.  In the few cases, tanks were forced to be part of a line at night and an attack happened, they often ended up alone since they had little chance of noticing their infantry was pulling back without them. This left the tanks very vulnerable to infantry close assault.

Infantry always had mixed feelings about armor.  They complained about it when it drew artillery fire, and it often did. When the ground pounders ran into something really dug in, even something like a light machine gun, if their ability to maneuver to flank and take it out was hindered, they really liked tanks. If there was even a hint or rumor, of enemy armor in the area, the infantry loved the tankers and their steel mounts.  A tank-infantry team, working together like a well-oiled machine, was hard to beat, as Germans and Japanese found out.

One thing the tankers were advised to do, is once an objective was taken, they needed to withdraw out of view of the enemy and off the objective so the infantry could reorganize and prepare for the standard German counter-attack. If they stayed on the objective, the amount of fire they drew, both direct, and indirect, made it harder for the infantry to reorganize, so the tanks would pull back and rearm and refuel and wait somewhere out of sight until they were needed again.  If they could not get out of view completely, they would have to do maintenance, under harassing mortar or artillery fire.

A whole tank company or more parked in a sqaure.
Several Companies of Tanks parked in a town square. A large mix of M4 types. The crews are probably living in the surrounding buildings. This is a really interesting photo, and I found out it’s the 752nd Tank Battalion in Italy. The location is Plaza Emanuel in Bologna. (UPDATE: We got a great comment from a reader, Tommaso Gollini, ‘the pic taken in Bologna (my hometown) is fantastic. I already saw it in other places. Our main square is called Piazza Maggiore after the end of WW2 but was called Piazza Vittorio Emanuele at the time of the pic. The members of the tank battalion weren’t lodged in the nearby buildings. The edifice on the back of the tanks is called “commune”, and was the place where the Major of the town (called Podestà during the fascism) and the government were operating. Mostly offices and such. On the left, the other edifice is called “Palazzo dei notai” and was the house of the notary corporation (also, offices). On the left of the Palazzo dei notai, not visible, there is our greatest church (San Petronio). On the other side of the pic, the left side of the tanks, there is another historical building. So it’s easier thinking the gi was just camped around spread in civilian houses, or in some other building, not in the pic’

I would say, just based on the fact a tanker rides in a tank everywhere they go, and that they get to carry more food and water and other things to make their lives easier. They also fight under armor, and though the inside of a tank may be hotter than hell, and smell bad, it was way safer than being an infantry soldier. Short of a direct hit from a large artillery piece, say bigger than 105mm, it would be safer to be inside a tank than in a foxhole. That they were not used to occupy areas also made their lives safer, but they have harder work to do. Working on a tank is hard, heavy, and dangerous work all on its own. But not having to walk everywhere is nice, and so is all that armor, and those cushy Sherman seats.

♦♦♦

In the Pacific, things were a little different.  At least for the Marines, it seems like they were rarely put ashore to train anywhere they could actually train on their tanks until very late in the war, before a battle. In one case the tanks were stored on an Island, and couldn’t even really be driven around, so the crews got no training time in the tanks before the battle.  After combat, sometimes there was little space for the tanks to pull back to reload and do maintenance, and out of desperation, they got used as part of the line occasionally.  This would make keeping the tank running a lot harder, but the Sherman was reputed to run even after a lot of neglect and abuse, and then when they finally did have a mechanical failure, it was easy enough to fix.

In a number of battles, the tanks couldn’t pull far enough back to be safe while they tried to reload and repair the tanks. Supply was a problem, particularly early in the battles, because of a combo of loading the tank supplies too deep in the ship and losing so much cargo as they tried to get it ashore. Getting spare parts for the tanks was hard, the crews would have to search around, and going through wrecked landing craft and amphibious tractors and that was if there were parts to be had. In most cases, spares were robbed from damaged and destroyed tanks.  I know of at least one case crews went through tanks that had been knocked out or swamped to get ammo for the next day’s fighting.

Crap on the Tarp tank style.
Ammo and weapons of an M46 laid out for inspection on the tank’s tarp. This was one of the few images I could find of a tank’s items out on the tarp for inspection, but it would look just like this with smaller main gun rounds!

As the war progressed, the tankers in the Pacific, Army, and Marine, learned how to use the Sherman to great advantage. After each campaign they improved their game, and as far as I can tell there really wasn’t much cross-pollination in tank tactics between the Marines and Army. In both cases tankers trained at Fort Knox, and yes the Marines sent officers through the armor courses the Army taught there, seemed to try and shoehorn standard armor tactics into the war in the Pacific, and in most cases, they just didn’t work. The Marines also put together their own Armor school eventually.

The threats the tanker in the Pacific faced were very different. Since they rarely could pull far enough back, they faced the real risk of Japanese night raiders attacking them. As a counter, they came up with a system of digging a trench under the tank and putting sandbags around the suspension and they would even go so far as setting up one of the M1919 machine guns in a sandbagged nest right in front of the tank. They could back out of these positions and then return and pull right in after they were done for the day.

The Pacific tank had no tank versus tank worries, in the extremely rare cases of US tanks running into Japanese tanks, the Sherman dominated. Japanese tanks were not well armed, well armored, or very common, and a Bazooka was a very serious threat to any of them. The real threat to the Sherman in the Pacific was the 47mm AT gum, any and all large-caliber artillery the Japanese may have had around, mines, though not seriously until late in the war, and Japanese Suicide squads with pole mines and satchel charges.

This M4 seems to be under fire, and has a lot of junk on the back. Notice the soldier looking at the camera.This M4 hybrid is loaded down with a lot of stuff. Probably in the Philippines.

The climate of the various campaign locations in the Pacific was pretty diverse. Early on, in the SWPAO, places like New Guinea, Bougainville, and Tarawa are pretty close to the equator and hot and humid, the Philippines are also in the tropics. Fighting inside a tank in these areas was not pleasant, and it wasn’t unheard of for crewmembers to pass out from the heat and smoke inside the tank. The environment offered almost as much danger to the Pacific tanker as combat since there were several diseases the caused mass casualties, the main being malaria. The US was very aggressive at controlling the malaria problem, issuing preventive medication and spraying massive amounts of DDT to kill mosquitoes.  Later in the war, the battles had left the tropics and were much like the battles in European climate-wise and the malaria risk fell off.

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Wounded crewmember being helped out of a damaged M4

Sources: Armored Thunderbolt by Zaloga, Yeide’s TD and two separate tank battalion books, Sherman by Hunnicutt, Combat Lessons, The Rank and file, what they do and how they are doing it 1-7, and 9. Archive Awareness, Oscar Gilberts, Marine Tank Battles in the Pacific,  M4 Sherman tank at war by Green, Tanks are a Might Fine Thing by Stout, the Lone Sentry, TM9-731b, TM9-752, TM9-754, TM9-759

#8 Sherman Accessories: Pimp Your Sherman YO!

Duplex Drives: wow, floating tanks and it worked!

duplexdrive16

The Duplex Drive Sherman story starts with the British. They came up with the idea of making a canvas skirt system for a tank and tried it on the Valentine tank. It worked so well they went on to try it on their M4A2s, and then on the M4A4s. They worked so well when they were shown to the US Army in a demonstration, the US Army was so impressed they decided to they would use some for the coming D-Day invasion. They had planned on just using Sherman tanks with deep wading kits and LSMs. They would use both.

Though any version of the Sherman could be converted if the M4A4 could, the US chose to only use M4A1 tanks. They wanted the most modern version they could get for the conversions the M4A1 76w, but the first 150 of these tanks were reserved for use in England for crew familiarization. They got M4A1 75 tanks, some late large models in the batch. At first, they thought the conversions could be done in England, but the complication of moving the air cleaner to the inside of the engine compartment made the conversions complicated enough it was decided to build and install the kits on tanks in the US, and the M4A1s were there waiting.

The kits were engineering marvels, if not a little fragile, they still worked very well. I think the impression they were failures comes from a single battalion that mostly sank on D-Day, but they launched into conditions that were known to be very dangerous for the tanks. All the other D-Day DD battalions had the vast majority of their tanks make it into shore just fine and then help a great deal on the landing beaches. The kit was made from a steel frame with rubberized canvas skirts. They were raised by inflating them. There was a little air pump mounted on the right rear of the tank’s engine deck that kept the inflatable parts inflated. Much of the structure that supported the canvas skirts were made of inflatable ribs.

The tank was propelled in the water by a pair of propellers built into a modified idler wheel mount. I don’t think they had a ruder of any kind and the tank was steered by braking with one track or the other. The British converted tanks were slightly different and had sprocket teeth added to the idler.  On the American conversions, these sprocket teeth were found to clog with sand and cause tracks to be thrown, so they were removed from the entire run of American made DD tanks. The kits included periscope extensions for the driver and commander so the tanks could, in theory, be operated buttoned up. There were extensions for the head and taillights for use in training only and extensions to the controls so the tank could be driven from outside. While in the water all DD conversions could make 4 ½  MPH.

In use, the biggest drawback was how fragile the skirts were both in and out of the water. Even a small tear would cause the DD to sink. There were several cases of DDs being lost because they tore their skirts driving off the ramp of an LCT. They were also vulnerable to bad weather, and the weather on D-Day was not ideal. It was only deadly for one tank battalion through.  The American 741st tank battalion launched 32 DDs 5000 yards from Omaha beach, 1000 more than ideal, into very rough surf conditions. 27 of the DD sank, 3 three from damage to their skirts, the rest foundered in the rough seas. They had it by far the worst accounting for most of the lost DD tanks.  Of the 122 total launched, this total is all the DD tanks, British and American, 36 were lost, and that includes all the tanks from the 741st. When they were used in other landings later in the war they had a better success rate. They also came up with metal flaps to cover the screen when it was down, to protect it from being torn on just about anything.

duplexdrive1

For more detailed info, check out the info on the Sherman Minutia Site.

M4 105 with dozer kit.

M4A3-Sherman-105mm-Dozer-latrun-1

Dozers:

Dozers got so big, it has its own post! Click here to go to it. 

Hedge Row cutters:

Hedge Row cutters were developed during the fighting in the hedgerows of Normandy, They were basically sections of tank traps from the beach, cut into crude cutting blades and mounted to the front of a Sherman tank.  They allowed the Sherman to charge through a hedgerow, cutting a Sherman wide hole through it. They probably looked scary to the Germans too.

Calliope: A Sherman with Rockets!

T34_Calliope_14AD 0_78d7_a08c5401_orig 0_12eb6_9d37ac5d_orig (1) M4_Sherman_T34_Calliope (1)

The E9 kit:

Sources: Armored Thunderbolt by Zaloga, Yeide’s  The Infantries Armor, and Steel Victory, Sherman by Hunnicutt, The Sherman Minutia Site, Son of a Sherman by Stansell and Laughlin, M4 Sherman tank at war by Green

# 7 More Things Built On The Sherman Chassis: ARVs

M30 and M74 series of Armored Recovery Vehicles: Tanks Get Stuck, ARVs get them unstuck

The M31, M32, and M74 armored recovery vehicles based on the M3 Lee and M4 tanks and almost all their sub-chassis types seem to have been used in the conversions as well.

ARVs Based On The Lee Hull: The Combat RV Gets A New Role

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A nice colorized photo of an M31, you can see the fake gun/door into the tank. Note the side doors are welded closed.

M31: based on the Lee, and there were subtypes based on other Lee hull types. 509 Lees were converted. This version was powered by the R975.

M31B1: was based on the M3A3 and 296 were converted. This version was powered by the 6046.

M31B2: Was based on the M3A5. I am unsure how many of this version was made.  This version was also powered by the 6046.

There was other Lee based conversion, but ‘A history of the American Medium tank’ doesn’t have production numbers for them. On the Lee conversions, the 75mm gun mount was replaced with a door, that had a dummy 75mm gun, and the back of the 37mm turret had a fake 37mm gun, and the front had a boom for lifting things like motors, or turrets.  The idea was to make it look like an armed Lee. A crane was installed in place of the 37mm gun and mount, and it had a 10,000 capacity.  With boom jacks, it could carry 30,000 pounds. It was also equipped with a 60,000-pound winch. The M31s had a single .30 caliber machine gun, in a fixed hull mount!

The information I have here is very basic, but the Sherman Minutia Site has a very nice history, with very nice photos, of the M31 series. Joe Demarco is an unsung hero of Sherman research, and he put the page together, and it is far better than what I have here, right now, it just covers the ARVs based on the Lee, but I’m sure more will be added over time. You can find the page here, the first link is to the main page. If you have not taken the time to check out the Sherman Minutia site and you like this site, you should love them!

ARVs Based on the Sherman hull: They Ran Out Of Lee Hulls.

M32: Was a tank recovery vehicle based on the M4 Sherman hull, 163 converted.

M32B1:  Was a TRV made from an M4A1 hull. There were 1055 M4A1 tanks converted

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A Very nice M32A1
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M32B1

M32A1B1: This version received an update, to A1 status, which meant improvements to the recovery capability and HVSS. There were only 37 of these converted.

M32B2:  TRV based on the M4A2 hull. There were 26 of these conversions.

M32B3:  TRV based on the M4A3 hull.  There were 318 of these tanks converted.

M32B4:   TRV based on the M4A4 hull. One pilot model made, not approved for production.

T14E1: was an M32B3 with HVSS made for the Marines in the last half of 45. They produced 80 of these.

The M32 series had a 60,000-pound winch, powered by powered take off, or PTO, from the drive shaft. The winch was mounted behind the driver and its drum mounted to the vehicle centerline outside. It had a crane mounted on the front of the hull, and the crane was moveable, folding back over the TRV for storage. It had an A-frame used for towing mounted on the rear hull.  It had stabilizers in the suspension that locked it in place when using the boom. If an M32 was equipped with HVSS suspension it was designated as with an A1.

The M32 was armed with an M2 .50 caliber machine gun, mounted on the top of the vehicle, on the main hatch. They also retained the bow-mounted thirty caliber machine gun. The early version was also equipped with an 81mm mortar to put out a smokescreen, it had 30 smoke rounds available. All these weapons were purely defensive, and the last thing an ARV crew wanted to do was get shot at.

M32-ARV-batey-haosef-2

The M74 ARV: In early 1954, Bowen McLaughlin-York Inc. began production on the M74, converting M4A3 tanks to this configuration. Rock Island Arsenal conversions around this time and continued into 1958 but no total number of the conversions is known.

These ARVs had a 90,000-pound winch and a hydraulically raised boom. It also had a spade on the front to help stabilize the vehicle when the boom was being used. The spade was hydraulic and could be used for light dozing work. These updates allowed the vehicles to retrieve heavier medium tanks like the M26 and M46 and were only replaced in service by the M88.

The M74 had an M2 .50 caliber machine gun mounted on its all-around vision cupola. It also retained the bow machine gun.

. . .

m4a1_lima35

Tanks when in combat and when not in combat break down, get stuck in the mud, sand, or on a tree stump. A pair of trees too close together could hang a tank like a Sherman up. Mines blew off tracks and damaged the suspension. It was not unheard of for a tank to fall into a basement, or cause a bridge to collapse. Sometimes they tip over or lose a track or have a major mechanical problem and won’t run; it’s nice to have an ARV around and for some of the above cases like recovering a tank from a stream after a bridge collapsed, the boom and rigging on an ARV are essential.

ARV’s were assigned to tank battalions; usually, a pair of them would be assigned to the Battalion HQ Company with a dozer tank. I will need to dig up a tank battalion TO&E to confirm this. I’m sure the units that went out and salvaged knocked out tanks and repaired them would have these vehicles as well, though I’m pretty sure I read they used M26 Dragon Wagon trucks. If you need help with pulling a turret, final drive, and tranny housing, changing a motor, or repairing mine damage an ARV crew would be useful to have around.

These vehicles would be assigned one per Tank. I have not read any accounts of what an ARV crew charged in WWII or Korea, but, I read has to be pulled out of a rice paddy in Vietnam would cost the crew several cases of beer. I wonder how it worked in Korea and WWII.

One more interesting note on the ARV program, the turrets from all these conversions were stored. Later, when M4A3 and M4 Composite hull 75mm production was still going, they collected these turrets and shipped them to the factories still producing 75mm tanks and used them instead of casting more. The turrets that came from early runs that did not have the thickened cheek armor, had it added, and since most had no loaders hatches, they were added too. I think most of these modified old turrets went onto M4 composite hulls.

Tank Park, Jumbo in the front, but note the M32A1 to the right
Äâå ÁÐÝÌ ARV M31 (èç 3rd AD) âîçëå ïîäáèòîãî "Øåðìàíà". Saint-Fromond, Íîðìàíäèÿ, 14.07.1944ã.*
A pair of M31s tow away an M4 that has been knocked out

#6 WWII Variants Other than Tanks: Things Built Using the M4 Chassis, Like the M10 and M36

WWII Variants, Other Than Tanks, Based on the Sherman: The Main being TDs like the M10 and M36

Tank Destroyers: Tank Hunters, Failed Role, Successful Killers

  They did great things but the whole idea was bad. The TD Battalions of the US Army had very good combat records, but the whole concept was flawed. The idea of holding back battalion-size units to be rushed in to fight the tanks in a major attack just didn’t work in practice, and since the US Army was on the attack most of the time, the TD units ended up being used a lot like the separate Tank Battalions, just not as good at it.

The Vehicles themselves proved useful and often found themselves attached to Tank Divisions, and used in ways never planned for, like direct infantry support.

M10: The First M4 Based TD to See Combat.  

Click the link above for a dedicated page on the M10. ↑

M10
A late production M10 with duckbill counterweights on the turret and wading trunks engages targets in France.

M10: The First Good American TD

The M10 was a tank destroyer mounting a 3-inch anti-tank gun. It used the M4A2 chassis with the GM 6046 to power it. These tanks only had an M2 .50 caliber machine gun other than their main gun. The turret lacked a power traverse. It had a five-man crew and was generally liked by its crew. The American TD force was deemed a failure, but not because the men or vehicles performed badly, it was the doctrine that failed to pan out, the battalions themselves performed well overall. It was used until the end of the war, and many TD battalions preferred it over the faster M18.  The TDs lacked a co-ax machine gun, this and their open-top made them more vulnerable to infantry than a tank. Even so, these units were often given tank missions. The open-top did offer a big advantage in finding any enemy tanks to shoot, and spotting close infantry.

One aspect of the design that shows how rushed it was, is the driver’s hatches. They were larger than the Shermans, but could not be opened or closed if the turret was forward. So the crew had to make a choice if the driver and co-driver were going to be able to see well or be buttoned, before the battle or movement.  The M10 lacked a turret basket, so the driver and co-driver had an easier time getting out of the roofless turret. Like all American designs, it went through a series of upgrades through its service life. The turret was upgraded and balanced better, and the crews liked to add their own roofs.  Extra machine gun mounts were a common modification. A power turret drive was never added to the tanks in US service.

The M10A1 version of this vehicle had a Ford GAA engine. There was no difference other than and minor improvements between an M10 and M10A1. Crews added on armored roofs to their turrets, often all hinged so they could open up to really see what was going on, in the field. It was not uncommon for TD units to be used as fixed artillery for several days. This was common practice in the MTO.

The M10 Turret went through several changes, the first versions were badly out of balance, and they tried to solve this by mounting the grousers for the tracks on the back of the turret. This didn’t work well and wedge-shaped counterweights were added. This helped, but eventually, the final production M10 turrets were widened, and even bigger counterweights were added with a distinct duckbill look to them.  They came up with a full roof armor kit for the final turret, and a half cover for the early turrets that could be field retrofitted. In spite of these minor issues, the M10 started out popular with the troops, and never lost that affection.

The M10 and M10A1 had all the gear aboard to be used at artillery. A few TD battalions spent almost as much time as artillery as they did in their TD role. This capability was used often in Italy because the 3 inch gun on the M10 didn’t tear up the vital roads as much as the larger guns did. I would be surprised to find out the M36 didn’t have the same gear. They built 4993 M10s and 1713 M10A1s. At first, only M10 TDs were authorized for service overseas, and the M10A1, even though found to be automotively superior, was to be used in stateside training only. There was some doubt about the usefulness of the motorized TD before the Normandy landings, and production of the M10 was halted as many TD units were converted back to towed gun units or disbanded.

The M10 saw action in North Africa, Sicily, Italy, and Northern Europe, and various Pacific Campaigns, the most notable being the retaking of the Philippines. It wasn’t really until the action started after the Allies went into Normandy that it really saw a lot of anti-armor use. In the MTO the TD units spent an awful lot of time being used as artillery units, to the point they had to learn how to swap barrels on their 3-inch guns after wearing the tubes out. The M10 in northern Europe saw lots of action but was also being replaced by the M18 and M36. The M36 was very popular, the M18 was mixed, some units love it, some units refused to give up their trusty M10s. The M10 was not popular in the Pacific, the thinner armor, lack of hull and co-ax machine guns and open top made for a much easier target destroy for Japanese troops.

M10_Wolverine_St_Fromond_France_703_TDBn_3ADiv

An M0 on the move in St Fromond France. The M10 is with the 703 TDB attached to the 3rd Armored Division.
M10_Wolverine_Tank_Destroyers_30th_Infantry_Division_Magdeburg_Germany_1945
A pair of M10 TDs supporting the 30th Infantry in Magdeburg Germany in 1945
M10_Wolverine_Tank_Destroyers_Head_For_Front_In_Tunisia_1943
A semi-early M10 with wedge-shaped counterweights on the way to the front in Tunisia, 1943
M10_Wolverine_77th_Infantry_Division_Leyte_Island_1944
An M10 or M10A1 supporting the 77th Infantry Division on Leyte 1944
M10_M4_Jeep_And_2_12_Ton_Truck_76th_Infantry_Division_Speicher_1945
M36 GMC moving through Speicher in 1945 supporting the 76th ID(Good Eye Stephen Weaver)
M10_Wolverine
An early M10, maybe at the Ford plant.
M10_Wolverine_And_M4_Sherman_77th_Infantry_Division_Leyte_Island_1944
Another M10 supporting the 77th ID on Layte in 1944
M10_Wolverine_32nd_Infantry_Division_Tank_Destroyers_At_Aitape_New_Guinea_1944
M10 supporting the 32nd ID near At Aitape New Guinea
M10_Moving_Thru_Hurtgen_Forest_893rd_Tank_Destroyer_Battalion
An M10 with the 893rd TDB moving down a snow and mud covered road in the Hurtgen Forest
M10_Wolverine_Tank_Destroyer_77th_Infantry_Division_632_Bn_Ormoc_Leyte_Philippines_December_1944
Late production M10 supporting the 77th ID near Ormoc in the Philippines 1944
Destroyed_M10_Tank_Destroyer_35th_Infantry_Division_454th_Tank_Destroyer_Bn_Livarchamps_Belgium_Battle_Of_Bulge_1945
An early M10 with the 454th TDB knocked out during the fighting at the beginning of the Battle of the Bulge
M10_Tank_Destroyer_And_Jeep_Enter_Fresnes_France_1944
This is an M10 entering Fresnes France in 1944, unit known.
M10_Tank_Destroyer_Moves_Into_Artena_Italy_1944
An M10 moves into Artena Italy in 1944, unit unknown.
Crew_Of_A_Us_Army_Repair_Unit_Working_On_A_Shell-Damaged_Tank_Destroyer_At_An_Ordnance_Depot_Near_Anzio_Italy_1944
This image shows a repair crew fixing an M10 damaged by artillery or mortar fire near Anzio, Italy 1944
Us_Marine_M10_Tank_Destroyer_Advance_On_Pto
An Army M10 somewhere in the PTO probably in the Philipines.
Us_Tank_Destroyer_M10_GI_With_Bazooka_Fontainebleau_France_23_August_1944
An M10 supporting US troops entering Fontainebleau France in August of 1944
M10_Tank_Destroyer_Heads_To_Battle_Lines_At_Bir_Marbott_Pass_East_Of_El_Guettar_In_Tunisia_1943.
An early M10 heading to the fighting near Bir Marbott past, east of El Guettar Tunisia, in 1943.
M10_Wolverine_Givenchy-En-Gohelle_Calais_1944
M10 in the French town of Givenchy En Gohelle near Calais France, 1944
M10_Tank_Destroyers_At_Ford_Plant_In_Detroit_1943
M10 tank destroyers rolling out of the Ford Factory in Detroit, 1943
M10_And_M4_Tanks_On_Production_Line_At_Ford_Plant_1943
M10 and M4A3 Shermans being built side by side at Fords plant in 1943
M10_Wolverine_Tank_Destroyers_On_Production_Line_At_Ford_Plant_1943
Another shot of the Ford M10 line in 1943
M5_And_M10_Wolverine_2nd_Armored_Division_In_Tesey_Sur_Vire_France_1944
An M10 supporting the 2nd Armor Division near Tesey Sur Vire France, 1944
KO_M10_Wolverine_803rd_Tank_Destroyer_Battalion_Ubach_Germany_1944
An M10 with the 803rd TDB in Ubach Germany late 44
M10_773rd_Tank_B_90th_Div_Mainz_Germany_1945
An M10 with the 773rd TD Battalion, supporting the 90th ID near Mainz Germany in 1945
30th_Infantry_Division_And_823rd_Tank_Destroyer_Battalion_M10_Germany_1945
30th ID doughs ride on 823rd TDB M10 in Germany, 1945
M10_32nd_Infantry_Division_632nd_Tank_Destroyer_Battalion_At_Aitape
This is an M10 in the Pacific, the crew is cleaning the gun, and the TD is with the 632 TDB on At Aitape
157th_Infantry_Regiment_Supported_By_M10_Tank_Destroyers_Of_A_Company_645th_Td_Bn_Under_Fire_In_Town_Of_Niederbronn_France
M10 of A Company, 645th TDB, Supporting the 157th Infantry Regiments, in the Town Of NiederbronnFrance
Camouflaged_M10_Tank_Destroyer_And_Harley_Davidson_In_Percy_France_08_1944
M10 in Percy France in 1944
M10_Wolverine_Aachen_1944
M10 in Aachen 1944
M10_Free_French_3rd_Algerian_Division_In_Omia_Italy_1944
M10 serving with the Algerian Free French 3rd Division in Omnia Italy in 1944
M10_Wolverine_Tank_Destroyer_Halloville_France_November_1944
An M10 near Halloville France, November of 1944

M36: The M10 With A Much Better Gun

Click the link above for a dedicated page on the M36. ↑

M36-GMC-Danbury.0004zx4t

Another tank destroyer based on the Sherman chassis, basically an M10A1 with a new turret mounting a bigger gun. These tanks mounted the 90mm M3 gun. Often this tank’s turret was fitted to otherwise stock M4A3 hulls due to a shortage of M10 hulls. These TDs had full power traverse. These TDs were well-liked because the M3 worked well on both armor and soft targets since the M3 had a nice HE shell.

m76f telescope reticle m76f

M36B1

This TD suffered all the same problems dealing with infantry the M10 did, except in the M36 B1, since it was built on an M4A3 hull, it had a bow machine gun. This was as close to a factory produced 90mm Sherman during the war. It was also upgraded in a lot of units with some form of roof armor. It solved the drivers and co-drivers hatch problems and always had a power turret drive though.

m36 turret dia

There was a diesel-powered version based on the base M10 chassis powered by the GM 6046. There were 1413 M36s, 187 M36B1s, and 724 M36B2s.  They produced it on the M4A3 and M10 hulls because they ran out of M10A1 hulls, and no more were going to be produced. Demand for the vehicle was so great they used what they had available.  As far as I can tell they saw use only in Europe with the US Army, but the French used them in Indo-China (Vietnam).

American soldiers of Patton's Third Army standing in front of their M36 TD while rolling up a Nazi flag they have taken as a trophy after the capture of Bitberg.
American soldiers of Patton’s Third Army standing in front of their M36 TD while rolling up a Nazi flag they have taken as a trophy after the capture of Bitburg.
M36_Jackson_and_Maginot_Line_Pillbox_776th_Tank_Destroyer_Bn_Hottviller_France_1944
M36 TD with the 776th TD Battalion, near Hottviller France, next to a Maginot Line pillbox 1944
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Factory fresh M36B2, waiting to be issued to troops
M36_Slugger_Tank_Destroyer_Tested_at_Aberdeen_1945
M36 being tested at Aberdeen Proving Ground 1945
M36_Jackson_Ardennes_Offensive
M36 in action during the battle of the bulge.
M36_702_Bn_Roer_River_1944
An M36 TD with the 702nd TDB near the Roer river, in 1944. It may be being used in the indirect fire role.
Line_of_M36_Tank_Destroyers_at_Repair_Depot_in_France_1944
What looks like a line of brand new M36 TD in a Depot somewhere in France in 1944.
M36_Jackson_in_the_streets_of_Metz_November_21_1944
This M36 looks like the crew are looking for something to shoot at. The photo was taken on the streets of Metz in November of 1944
M36_35th_Infantry_Division_654th_TD_Bn_in_Oberbrauch_Germany_1945
This M36B1 just took a shot at something, note all the smoke coming from the open turret, and how the commander appears to be looking at something. The photo was taken in Oberbrauch German in 1945 and the TD is with the 654th TDB
M36_Jackson_Tank_Destroyer_1944
M36B1 outside probably the Fisher plant in 44.
M36B1_ank_destroyer_1945
An M36B1, 1945, location and unit unknown

. . .

Artillery: they have big guns, and their crews are usually deaf. (Coming soon)

 

105 Howitzer motor Carriage M7& M7B1: 4316 produced

155 Gun Motor Carriage M12: 100 produced

155 Gun Motor Carriage M40: 418 produced

8 Inch Howitzer Motor Carriage M43: 48 produced

 

Sources: Sherman by Hunnicutt,  TM9-745, TM9-748, TM9-731b Yeide’s The Tank Killers, Armored Thunderbolt by Zaloga

#5 Combat Performance: How Well it Killed Stuff.

Combat Performance: It Killed Stuff Pretty damn well.

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A line of Sherman II tanks

When Sherman went into combat in British hands in the North African desert in October of 1942, it was bar none, the best tank in the world. It had a better gun and more armor, along with good or better mobility than all the axis tanks it faced. It wouldn’t have a German peer until the Panzer IV was up-gunned and even then, the best version of the Panzer IV was barely a match for a 75mm armed Sherman and totally outclassed by the later 76mm armed tanks. The Sherman tank was designed, and the design improved to maximize how easy it was to produce, while also improving the reliability, crew fighting efficiency, safety, and comfort. This was fairly unique to U.S. Tank design and can be attributed in many ways to the automotive production experts who came out of Detroit and the US Auto industry.

The basic small hatch Sherman was found to be fine for the job all the way through the invasion of Italy and Normandy. The introduction of the Tiger and Panther as specialized tanks that were rarely seen. In the Tigers case, they were right. It was a rare and more or less useless waste of German resources. The Panther would become much more common after the break out from Normandy, but if you really look at its performance, it was not that great of a threat. In most cases when they met in Europe, the Sherman won. The 75mm M3 Armed Sherman was very well equipped to deal with infantry and AT guns, the main threat they would face, and this was part of why the US Army didn’t want to jump to the available at the time of Normandy, 76mm armed Shermans.

The US Army tried the M1 gun out on the Sherman just about when the Sherman 75 hit production. The Sherman Minutia Site has images and covers the history, as do various books,  the M1 gun fit, but was a tad long, so they just chopped off more than a foot from the barrel. It worked well enough they ordered 1000 Shermans armed with the gun, but then the order was canceled because the turret was too cramped. Later, they would adapt the T23s turret to the Sherman hull for a much better solution to the problem of up gunning the tank.  After the war, the many 75mm Shermans were up-gunned with the M1A2 gun and then given to allies as military aid. A fun way to see a few of these tanks in action is to watch the 70s movie, Kelly’s Heroes, the Shermans in that are all up-gunned 75mm turreted M4A3 tanks.

The Sherman, even the version armed with the 75mm gun, could still deal with the heavier Nazi German tanks, as long as it had room to move around, and knew where it was. Much noise has been made about how it was a death trap after the D-Day landings and the Panther and Tiger tore it up in the bocage. This is a myth. There is pretty good evidence the US Army only faced maybe two or three Tiger I tanks, in Europe, ever. The Panther was more common, but also got roughly handled in just about every battle it faced Shermans in.

The German’s rarely used the Panther in the bocage country because its long gun made it hard to use in the tight quarters and reliability problems were ever-present with this tank. The tank the Sherman faced in US hands was the Panzer IV and various Stug assault guns, neither of which outclassed the Sherman in any real way. But they did have the advantage of being on the defense.

Post-war studies by the US Army showed the Sherman was more effective than German armor at this point. The claims of the Sherman being a death trap were false. Even early Sherman tanks were no more likely to burn than any other tank and the later war wet ammo rack tanks were the safest tanks of the war. German tanks used gasoline and gas was not found to be a major cause of fires in destroyed Shermans, ammo fires were. See the links in the data section for info on this. Most Sherman losses were due to anti-tank guns, infantry AT weapons and mines, and not so much tank on tank action.

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When Operation Cobra was kicked off, the first use of a large hatch hull, wet ammo rack, 76mm armed Shermans took place. The M4A1 76 being the model used first followed by A3 76 tanks within weeks. These tanks were not well received across the board, with some units preferring the 75mm armed tanks because facing armor was rare even then and the 75mm gun was better at taking out anti-tank guns and infantry, and could still deal with any German armor they encountered. Some units welcomed the better anti-tank capability even if it wouldn’t kill a Panther from the front unless at very short range.

By the battle of the bulge, the M4A3E8 and M4A3E2 Jumbo were showing up for combat use. The Jumbo had much thicker armor and were loved by their crews. By the close of the Bulge, German armor would become very rare, but even so more and more 76mm armed Shermans would be issued. By the end of the war, the ratio would be near 50%. The Army also wanted to stop production on the 75mm gunned M4s in 1945, but the USMC and the British still had requirements for the 75mm gun tanks so it stayed in limited production.

There was a bit of a scandal about the Sherman being no good in the press back in the States about the time of the Bulge. The reality was, the Sherman was having its shining moment during that battle and performed very well against German armor that was supposedly better. Bad movies aside, the Sherman more than held its own in the Battle of the Bulge, also known as the Ardennes Offensive. This is covered in Steven Zaloga’s Armored Thunderbolt, in much more detail.

By the time the next generation replacement showed up, the M26, the war was all but over, and only a handful would see combat. In many ways, the M26 was inferior to the M4. Due to its slightly shortened development and testing time, it had a few reliability problems. It was still so reliable that it would have put any German tank to shame though. The motor, though stressed more in the M26, was the GAA, and it was solid and reliable. The very early tanks had some transmission issues, that were resolved, and some minor things like bracing the final drive housings and changing the drive sprocket configuration were the only major changes. It was never as reliable as the Sherman, but it was close enough to be adopted for use by the Army and Marines.

♦♦♦♦

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M4A1 tanks coming off a floating doc from an LST. the LST does not get enough credit for being a technological marvel of its time and something Nazi Germany had no ability to produce.♦
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M4A2 76W lend-lease tank in Soviet use, note the ever-present log on the Soviet Sherman, the infantryman is kneeling on it. I built a dragon M4A2 76w like this once in 1/35 scale. The Soviet crews were sad to see their tanks destroyed per the lend-lease agreement at the end of the war. When watching the US and Brit freighter crews dumping the tanks in the ocean instead of taking them home, they stopped giving them back. They turned them into tractors by removing the guns and turret.♦

This M4A1 seems to be under fire, and has a lot of junk on the back. Notice the soldier looking at the camera.
M4 composite hull under fire in the Philippines, and just look at all the stuff they have packed onto the back of the tank, and note how it’s all tied down. ♦
US_3rd_Armored_Division_M4_Sherman_Tanks_in_Action_in_Belgium_1944
An M4A1 76w and an M4 of the 3rd AD Shermans in action in Belgium, 1944. It looks like the M4A1 76 has an air recognition panel on the rear deck. 
3rd Armored Division, Stolberg, 1944
An M4 with the 3rd Armored Division, near Stolberg Germany, 1944. The tank appears to have all the “quick fix” upgrades.♦
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Looking for a sniper, an M4A3 76w, and an M4A3E8.♦
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A late production small hatch M4A1 75 passing knocked out Nazi PIV tanks. ♦
Marienburg-Sherman-Pz4
Another small hatch M4A1 75 passing a knocked out Nazi PIV, this M4A1 has what looks like an extra steel plate attached to the front of the hull. ♦

♦♦♦

Sources: Armored Thunderbolt by Zaloga, Yeide’s TD and two separate tank battalion books, Sherman by Hunnicutt, Combat Lessons, The Rank and file, what they do and how they are doing it 1-7, and 9.  Archive Awareness, Oscar Gilbert’s, Marine Tank Battles in the Pacific, WWII Armor, Ballistics and Gunnery by Bird and Livingston,  M4 Sherman tank at war by Green, the Lone Sentry, the data in the data section

#4 Sherman Builders: Just How Many Tank Factories Did the US Have Anyway?

DTA_Summer_1942_TA-1583
CDA pumping out M4A4 tanks in 1942

Sherman Builders: They Had 10 and 1 in Canada. 

Most of the information in this section will be a summation of the section from the book Son of a Sherman. Other stuff I had to dig around on the internet for. Anyone who has more info on the tank makers, please feel free to contact me.  Parts from all these tank makers would interchange. Many used the same subcontractors. I don’t think anyone has tried or if it’s even possible to track down all the sub-contractors who contributed parts to the Sherman at this point. Some of the manufacturers were more successful than others, some only producing a fraction of the total Sherman production, others producing large percentages. By the end of production, all the US and her allies ‘ needs for Shermans were being handled by just three of these factories.

American Locomotive (ALCO)

Sherman m4a2 being built at Alco

ALCO also produced M3 and M3A1 Lees and made Shermans up to 1943. They were a fairly successful pre-war locomotive manufacturer founded in 1901 in Schenectady, New York. They also owned Montreal Locomotive Works. ALCO made several versions of the Sherman, and stayed in the tank game until the late 50s, helping with M47 and M48 production. The company went under in 1969.

Baldwin Locomotive Works (BLM)

BaldwinLocomotive_PHist

Baldwin was another early producer, building three versions of the Lee, The M3A2, M3A3, and M3A5. They mostly built small hatch M4s, with just a handful of M4A2(12). They were out of the Sherman game by 1944 and out of business by 72. They were founded in Philly in 1825 and produced 70,000 steam locomotives before they died.

Chrysler Defense Arsenal (CDA)

m4a4_26CDA
M4A4 Tanks being built as the last Lee goes off the line

Chrysler Defense Arsenal is kind of special. It was a purpose-built tank factory, funded by the US Government, and managed and built by Chrysler.  Construction of the factory started in September of 1940. Completed M3 Lee tanks were rolling off the line by April of 1941. This was before the factory was even finished being built. It was built to stand up to aerial bombing. They produced M4A4, and M4 tanks as well and M4 105s, M4A3(105)s, and M4A3 76 tank and nearly 18,000 of them. Chrysler was the sole producer of M4A3E8 76 w Shermans, or the tank commonly known and the Easy 8. They produced 2617 units, but post-war many A3 76 tanks were converted over to HVSS suspension. A very big chunk of the overall Sherman production came from this factory and it went on to produce M26 Pershing tanks.

Chrysler built this factory in a suburb of Detroit, Warren Township Michigan. Chrysler used its many other facilities in the Detroit area as sub manufacturers, and many of their sub-contractors got involved too. CDA not only produced the tanks, it also had the capacity to pump out huge numbers of spare parts.  CDA lived into the 90s before Chrysler Defense Systems got sold off to General Dynamics. It took part in making the M26, M46, M47, M48, M60, and M1 tanks.

M3_Lee_Tanks_On_Assembly_Line_at_Chrysler_Plant_in_Detroit-3
The M3 Production line at CDA
M3_Lee_medium_tanks_on_assembly_line_at_the_Chrysler_Corporations_Tank_Arsenal_in_Detroit_1941-2
Another shot of the CDA Lee production line
M3_Lee_tanks_on_assembly_line_at_the_Chrysler_Corporations_Tank_Arsenal_in_Detroit_1941-2
One final shot of the Lee production line at CDA, this on earlier in the build process

Federal Machine & Welder (FMW)

I couldn’t find much out about FMW, Son of a Sherman says they were founded in Warren Ohio in 1917. They produced less than a thousand M4A2 small hatch tanks.  They were slow to produce them, making about 50 a month. They were not contracted to make any more Shermans after their first 540 total, 1942 contract.  They did build some M7  GMCs and M32 tank retrievers. They were out of business by the mid-fifties.

Fisher Tank Arsenal (FTA)

M4A3E2_15

Fisher Tanks Arsenal (FTA) has a lot of common with Chrysler Defense Arsenal, except this time Uncle Sam went to Fisher Body, a division of General Motors. Fisher decided to build the tank plant in Grand Blanc, south of Flint Michigan. The factory broke ground in November of 1941 and the first M4A2 Sherman rolled off the line in January of 1942 before the factory was fully built.

The M4A2 was something of this factory specialty, in particular early on, with them producing a large number of the small hatch M4A2 sent off to Russia, and a few of the rarer large hatch 75mm gun tanks, around 986 small hatch tanks, and about 286 large hatch tanks.

M4A2 FISHER AD

They also produced nearly 1600 large hatch, 76mm gun tanks, or the M4A2 (76)w. These tanks went exclusively to Russia as part of Lend-Lease. These tanks were ordered over four different contracts and the final ones off the production line were all HVSS tanks. The HVSS suspension may have seen combat with the Russians before the US Army used it. Oddly, this factory also produced M4A3 76w tanks, but never with the HVSS suspension. Fisher produced a significant number of M4A3 and Large hatch 75mm tanks at their factory, but nowhere near their M4A2 production.

Ford Motor Company (FMC)

Ford_Engine_Line

Ford was a surprisingly small player in the Sherman tale. They are very important in that they developed the Ford GAA V8 covered earlier, and a lot of spare parts. But they only produced 1690 small hatch Shermans between June of 42 and Oct 43. They built a few M10s as well. All these tanks and tank destroyers were produced at their Highland Park facility.  After 1943, they stopped building tanks, and wouldn’t get back into until the 50s, and even then it was just for a large production run over a short time, of M48s.

Lima Locomotive Works (LLW)

m4a1_lima7 m4a1_lima71

Lima was one of the first producers of the cast hull M4A1. It did not produce any Lee tanks. Its production capacity had been taken by locomotives to the point just before Sherman production started. They produced the first production M4A1, that was shipped to England, named ‘Michael’, and it’s still on display at the Bovington Museum. They produced Shermans from February of 42 to September of 1943, producing M4A1s exclusively, and they built 1655 tanks.  The war was a boon for Lima, they’d been in business since 1870, and the contracts from the military for locomotives really helped them out. Postwar, they failed to successfully convert to diesel-electric locomotives and merged with another firm. 

Montreal Locomotive Works (MCW)

Handler Handler (4)

MLW was owned by American Locomotive. They produced some wacky Canadian tank based on the Lee chassis, called the Ram, and Ram II, these floppy creations were only armed with a 2 pounder in the Rams case, and a 6 pounder, in the Ram IIs case, and they produced almost 2000 of the wacky things, what’s that all aboot? They eventually got around to producing a proper Sherman tank, the M4A1 “Grizzly”, producing only about 188 tanks. A very few had an all-metal track system that required a different sprocket. Other than that, there was no difference between a grizzly and an M4A1 manufactured by any other Sherman builder. Don’t believe the Canadian propaganda about it having thicker armor!

Pacific Car & Foundry (PCF)

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PCF was founded in 1905 in Bellevue, Washington.  After they bought out their only real competitor in the early 20s, they were the only heavy machinery company and foundry in the Pacific Northwest. They were the go-to foundry for steel used in the building of many Seattle landmarks. In 1924 the founder, William Pigott sold a controlling interest in the company to American Car and Foundry Company. In most stories about a company, it would end right there, but in a twist of fate, the Son of William Pigott, Paul Pigott, bought back a controlling share of the company in 1934.m4a1pcf_1

At first, the company seemed to do ok during the great depression, but it was really on the ropes until just before WWII, when the increase in military spending helped them out. Their steel and aluminum were used in the B17, numerous Naval vessels, and tanks.  They were also one of the Sherman tank producers that could make their own M34 Gun Mounts. They produced enough other Sherman factories used theirs too.

The only west coast tank maker, PCF produced 926 M4A1s from May of 1942 to November of 1943. The foundry had the facilities to produce all the big casting, the M4A1 Sherman used, in-house. As soon as production stopped they started production on the M26 tractor, the truck portion of the M26 tank transporter, also known as the Dragon Wagon. They never got back into tank production again, but they did produce one very special tank destroyer. The almost mythical T28 super heavy tank and the army managed to lose one.

The Shermans they produced were used by units training up and down the west coast, and many were sent to the Pacific. Company A, of the 1st Marine tank battalion, received a 24 of PCF’s M4A1 Shermans, the only ones the Marines would use. These PCF Shermans have a few things that make them easier to identify, the easiest to see is the dust cover mount around the hull machine gun, PCF’s is distinct and made from a strip of steel instead of a rod. Many of these Shermans were produced with the T49 steel tracks. These tanks would see combat in the swamps and jungles of Cape Gloucester. A battle I will cover in detail later.

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PCF M4A1 on Cape Gloucester with the Marines
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T28_Super_Heavy_Tank

The T28, also known as the T95 105mm gun motor carriage, two of these massive vehicles were made, and PCF made both. They came in at 100 just under 100 tons and were designed to get a very powerful 105mm gun close enough to knock out heavy fortifications, like the type along the Siegfried line. It was also considered for use in the Invasion of Japan had that been necessary, and man, think of the weird porn the Japanese would come up with if we had invaded with a bunch of these bad boys, instead of nuking them. It had a set of double wide HVSS suspension on each side, with four bogie groups, and armor up to a foot thick. It had a four-man crew and used the same 500 horsepower Ford GAA V8 to move it. Yes, 100 tons, 500HP, a real hot rod that thing was. Development ceased after the war, and any kind of testing on the two prototypes stopped by 47. One prototype burned out, and was scrapped; the other just disappeared for several decades and was found in a remote spot on Fort Belvoir in Virginia. It is now stored in an army parking lot, not open to the public, rusting away.

Pacific Car & Foundry still exist today as PACCAR Inc., one of the largest truck makers in the world. They own both Kenworth and Peterbilt. They also produced much of the steel structure on the Twin towers of the World Trade Center. They built the PACCAR tower in Bellevue in in the late 60s and it’s still their HQ today. They are worth 18,8 billion as of 2013.

Pressed Steel Car (PST)

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PSC was one of the big boys of Sherman production, and they also produced the final M4s made, a group of 30 M4A1 76 HVSS tanks. PSC was founded in Pittsburg in 1899, but their tank factory was in Joliet, Illinois. They were the second manufacturer to make the tank and across all the versions they made, they produced 8147 Sherman tanks.

They started tank production with the M3 Lee in June of 41 and stopped production on that in August of 1942. They then produced the M4A1 from March of 42 to December of 43, and the standard M4 from October of 42 to August of 43.

They were one of the final three tank makers to stay in the tank making business after 1943, along with CDA and FTA. PSC would produce large hatch M4A1 76 tanks, including HVSS models late in the run, totaling more than 3400 M4A1 tanks. They produced 21, M4A2 76 HVSS tanks, towards the end of 45.

They were out of business by 56, with no tank production after those final 30 M4A1 76 HVSS tanks.

Pullman Standard (PSCC)

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Pullman Standard was a pretty famous luxury train passenger car maker and another company that made rolling stock combined into one company. Pullman Palace Car Co was founded in 1867, or thereabouts. I’m sure some train geek will be dying to fill me in on the company’s history but I’m not really going to look deeply into it. It does make for one of the more interesting stories about a Sherman tank producer. Their main tank factory was in Butler, Pennsylvania. And they helped produce some Grant tanks before they started Sherman production.

They produced the M4A2 from April of 42 to September of 43 and produced 2737 tanks. They also produced 689 standard M4 Sherman tanks from May of 43 to September of 43.  Soon after these contracts were finished the US Government broke the company up due to some anti-trust complaint.

The thing to remember about all the Sherman makers is each one had a small imprint on the tanks they produced. So, yes, an M4A1 small hatch tank was the same no matter who made it and all parts would interchange with no modification needed, but the tanks from different makers still had small, cosmetic differences. They may have been something like nonstandard hinges on the rear engine doors to the use of built-up antenna mounts instead of cast. Or wide drivers hoods or narrow, to where the lift rings on the hull were and how they were made or even Chrysler’s unique drive sprocket they put on all their post A4 tanks.  None of this meant the parts couldn’t be salvaged and used on another Sherman from another factory without much trouble. Some factories may have produced tanks faster than others, but they all produced them within the specification of the contract or they were not accepted.

Hanno Spoelstra of the Sherman Tank Register found this very cool old poster.

M4 production list

Sources:  Sherman by Hunnicutt,  Son of a Sherman by Stansell and Laughlin,  Tanks are a Mighty Fine Thing by Stout, various company websites