* The Allied Sherman Tank Pt 1: “Blunder” Or “Wonder” Weapon?

By the time of the Allied cross-Channel Normandy invasion of June 6, 1944, the American-built Sherman medium tank was admittedly inferior to its German opponents, yet still won the war in Northwestern Europe by numbers, not quality

As a young boy growing up in the United States in the mid-1950s, I---like thousands of others---enjoyed building and rebuilding the olive-drab, plastic M4 Sherman tank model made by the Revell Model Company of that era, and I can still fondly recall most of its details.

But for the Allied tankers and infantryman of the American, British, Canadian, and Free French armies battling German Panther and Tiger panzer tanks in Normandy in the summer months of 1944, the Sherman’s failures were glaringly evident as their own shells pounced off the hulls of the Nazi armor, and all the more so as they were themselves destroyed at a far greater range by their opposite numbers.

That having been said, it was also a cruel irony of fate and history that the outgunned and lighter armored Shermans nevertheless defeated the retreating Nazis by their sheer weight of numbers.

Today---more than seven decades after the end of the greatest war in military history to date---the debate continues: was the American-designed-and-built Sherman M4 medium tank a colossal blunder, a wonder weapon---or both?

According to author Philip Trewhitt in his 1999 work---Armored Fighting Vehicles---“The Medium Tank M4 Sherman used the same basic hull and suspension as the M3, but mounted the main armament on the gun turret rather than the hull. Easy to build and an excellent fighting platform, it proved to be a war-winner for the Allies.

“By the time production ceased in 1945, over 40,000 had been built There were many variants, including engineers tanks, assault tanks, rocket launchers, recovery vehicles, and mine-clearers.

“The British employed the Sherman extensively, notably at the Battle of El Alamein in 1942. Though outgunned by German tanks and with insufficient armor to compete in the later stages of the war, the sheer numbers produced overwhelmed enemy armored forces.

“Its hardiness kept it in service with some South American countries until very recently.”

With a crew of five, the Sherman weighed 6,000 pounds/31,360kg; was 19 feet 4 inches/5.meters long, was 8 feet 7 inches/2.6 meters wide, and had a height of 9 feet/2.74 meters.

It had a range of 100 miles/161 kilometers, armor of .59-2.99 inches/15-76 mm thick, and a single 75mm turret gun, plus one coaxial 7.52mm machine gun, and a .50 caliber/12.7mm anti-aircraft gun on the turret.

The power plant consisted of twin General Motors 6-71 diesel engines that developed 500 horsepower/363kW. Its maximum road speed was 2mph/46.4km/h, it could ford a stream 3 feet/.9 meters deep, mount a vertical obstacle 2 feet/.61 meters high, or cross a trench 7 feet 5 inches/2.26 meters wide.

Added the noted authority Bart Vanderveen in his 1989 study Historic Military Vehicle Directory, “The M4 series…first appeared in 1941, and was built throughout World War II by (American automobile firms) Chrysler, Ford, GM, and others…and comprised several basic types, plus numerous variants and derivatives.

“…Hulls were welded or cast, with the 1- or 3-piece nose bolted on.”

Its engines included the M4 and M4A1 Continental radial, the M4A2 twin GM diesels, the M4A3 Ford GAA V8, and the M4A6 Caterpillar radial diesel, all mounted at the rear. The transmission was a five-speed, synchromesh with controlled differential, and front sprocket drive.

The suspension consisted of vertical volute springs (horizontal on later models), and a 24-volt electrical system. The vehicle’s fuel capacity was between 140-175 gallons.

Continued Trewhitt, “The M4A3 was one of the most developed of all the Sherman variants used during World War II. It differed from the M4A2 mainly in the design of its turret and suspension, using a more effective horizontal volute spring system, and in its armament, employing the larger and more powerful 76mm gun as well as having thicker armor.

“This particular model was the production type most favored by the US Army. Ford built 1,60 A3s between June 1942-September 1943, before ceasing tank production. Manufacture was then taken over by Grand Blanc from February 1944. Improved features included a vision cupola for the commander, a loader’s hatch, and so-called ‘wet storage’ for the ammunition. In addition, its petrol engine was specifically developed for the vehicle.”

The M4A3 Sherman medium tank also had a five-man crew, a weight of 71,024 pounds/32,284 kilograms, and a range of 100 miles/ 161 kilometers. Its length with gun was 24 feet 8 inches/7.52 meters, and over hull 20 feet 7 inches/6.27 meters. Its width was 8 feet 9 inches/2.68 meters, and its height was 11 feet 2.85 inches/3.43 meters.

Its armor plating consisted of .5-3.94 inches/15-100mm, and its armament was a sole 76mm turret-mounted gun, plus a single 7.62mm coaxial machine gun. The power plant consisted of a Ford GAA V8 petrol engine developing 400-500 hp/335.6-373 kW. Its maximum road speed was 2 mph/47 km/h, its fording ability was 3 feet/.91 meters, it could surmount a vertical obstacle of 2 feet/.61 meters high, and a trench 7 feet 5 inches/2.25 meters wide.

These, then, were the basic M4 Sherman combat vehicles.

A note about the varying Allied versus German numbers is here in order: against those Allied 40,000 Shermans, the Nazis fielded but 1,835 Tiger and King Tiger tanks, plus a mere 4,800 Panther tanks, for a grand total of 6,635 versus 40,000 Shermans! Another source claims that fully 49,234 Shermans were built, and yet another rounds that figure off to an even 50,000.

Ironically, the US entered the Second World War without such a combat vehicle already at hand. Thus, its new design was developed too quickly and the normal, slow-moving series developmental stages were cast aside in favor of getting the M4 medium tank into immediate mass production. The Allies paid for this hasty decision later on, in the summer of 1944 in the fields and hedgerow country of embattled Normandy against far superior German armor.

The enormous production numbers also resulted from this initial, strategic decision, rather than wait for a heavier armored vehicle, such as the M26 Pershing model heavy tank, that finally arrived just before war’s end in 1945.

On the pro side of the ledger, the M4 Sherman was technically uncomplicated, reliable, and mechanically well constructed. It also helped that the Allied air forces enjoyed a huge aerial superiority over the virtually beaten German Luftwaffe/Air Force. Working in tandem with well coordinated Allied infantry, artillery, and air forces, the plentiful and trusty Shermans were able to vanquish most German armored formations in time, simply by ganging up on them in overwhelming numbers when all else failed.

On the con side, however, the Sherman’s 75mm and 76mm gun just couldn’t pierce the mighty Tiger tank’s frontal armor---even at short range---while the latter could vanquish the Shermans with impunity from greater distances on the very same battlefields. Another drawback was that---unlike the German tanks and the Soviet-built T-34 medium tank---the high-profile Sherman made for a far more visible target in combat because of its tall height.

In addition, noted one source, “In fact, to destroy a German Tiger, the Shermans had to hit it from the side or from behind, and---obviously---if the Tiger saw them approaching, it could destroy some Shermans before the others could eventually destroy it.” That was, alas, too often the case, moreover.

Power plants for US tank production was always a major problem, and eventually, this led to the development of the 8 cylinder Ford-produced engine. Although originally designed for aircraft, the Ford 8 cylinder engine was gasoline fueled and had 500 gross horsepower. Following testing, the engine was authorized for Sherman usage by January 1942 by the US Army Ordnance Committee and---as the “new” Sherman---was now known as the M4A3, with the first being completed by May 1942.

Testing was completed at the General Motors Proving Ground, with minor changes being made. By September 1943, fully 1,600 tanks had been constructed, when Ford ceased production. This was taken over by the Detroit Tank Arsenal and also the Fisher Tank Arsenal, and by mid-1943, there were already also numerous changes.

Stated one account, “Distinguishing turret features included an all around vision cupola for the commander---except in early production, which retained the earlier circular split ring hatch---and an oval shaped loader’s hatch. Those vehicles produced with the circular split ring commander’s hatch had it replaced by the all round vision cupola in the field as supplies became available.”

First came the M4A1, then the M4 105 howitzer model. The M4A3 came with its 75mm, then the 76mm and 105mm howitzer.

The Canadian Army replaced its Ram tank with the versatile Sherman model for the invasion of Italy in July 1943. Asserted one account, “It could not fire high explosive (HE) rounds.”

Named after the American Union Army Gen. William Tecumseh Sherman, the M4 medium tank was used in not only in World War II, but also in the Greek Civil War, the Arab-Israeli War, the Korean War, the Suez Crisis of 1956, the Indo-Pakistani War of 1965, the Arab-Israeli War of 1967, the Indo-Pakistani War of 1971, and the 1973 Arab-Israeli War as well.

The original M4 was developed on Aug. 31, 1940, with final characteristics completed on Apr. 18, 1941 at the Aberdeen (MD/USA) Proving Ground. The first pilot M4 was finished on Sept. 2, 1941, and then put into mass production during February 1942. There were seven models: M4, M4A1, M4A2, M4A3, M4A4, M4A5, and M4A6.

Stated one account, “The sub types differed mainly in terms of engine, although the M4A1 differed from the M4 by its fully cast hull rather than by engine; the M4A4 had a longer engine system that also required a longer hull, longer suspension system, and more track blocks.

“The M4A5 was an administrative placeholder for Canadian production, and the M4A6 also elongated the chassis but totaled fewer than 100 tanks. Only the M4A2 and M4A6 were diesel; most Shermans were gasoline fueled. The M4 might refer specifically to the single sub type with its continental radial engine or generally to the entire family of seven Sherman types, depending on context.”

In addition, “Many details of production, shape, strength, and performance improved throughout production life without a change to the tank’s production basic model number: more durable suspension units, safer ‘wet’ ammunition stowage and stronger armor arrangements such as the M4 Composite, which had a cast front hull section mated to a welded rear hull The British nomenclature differed from that employed by the US.”