American troops in the American Expeditionary Force (AEF) formed the 304th Tank Brigade, commanded by Lt. Col. George S. Patton Jr. Here are Renault FT light tanks from the 345th Tank battalion at the start of the Meuse-Argonne campaign in September 1918.
The path to an American light tank was not a straight or easy road.
US troops in the light tank battalions in the Great War used French Renault FT light tanks (often called FT17), armed with either an 8mm machine gun or a 37mm cannon. While plans were made to produce the Renault FT tank in the United States, those tanks did not arrive in time to take part in the final battles. The US 304th Tank Brigade, commanded by Lt. Col. George S. Patton Jr., thus operated French-built Renault FTs in the 344th and 345th battalions. They took part in the Saint-Mihiel battle in September 1918 and the Meuse-Argonne offensive in late September. Thought the FT tanks found the fighting hard going, with mechanical failures and fuel shortages, the tanks proved their worth and led to further interest in American-built tanks.
EARLY EFFORTS
The United States Army intended to produce tanks for US troops in the Great War campaign. The first design finished was the experimental Ford M1918 3-ton light tank, developed by Ford and offered as a light tank carrying a single .30 (7.62mm) weapon, originally a Marlin M1918 tank machine gun. This was changed to a .30 Browning M1919 machine gun. The Ford M1918 light tank had two Model T automobile engines with two planetary transmissions, giving two speeds forward and one speed in reverse. The two engines produced 34 HP, giving a top speed of 8 mph (11 km/h). Armour was limited, .5 inch (12.7mm) in front and .25 inch (6.35 mm) elsewhere. The M1918 3-ton light tank was a very small vehicle, only 160 inches (4 meters) long, 64 inches (1.6 meters) wide and 64 inches (1.6 meters) high. The driver was on the right and the gunner on the left. Tests proved that the M1918 was inadequate as a light tank, and it was recommended as a light artillery tractor. With the end of the war, only the original test 15 examples were built.
The M1918 three-ton Special Tractor was a light tank developed by Ford as a machine gun carrier and field tractor. This version carried a .30 Browning light machine gun in a ball mount.
The M1917 six-ton light tank, built by three production companies, was a copy of the Renault FT light tank. The Renault engine was replaced by a Buda four-cylinder engine, requiring moving the exhaust muffler (silencer) to the left side of the hull from the FT’s right-side position.
This Ford M1918 tractor towed light artillery, including the caissons, and was tasked with other duties, as in this picture, towing a field kitchen and supply wagon. The M1918 had a two-man crew – driver and hull gunner. The large front idler was to clear tall obstacles.
The M1917 tank was a small vehicle and major systems were easy to access for repairs and maintenance. Note the trench crossing tail assemblies hinged down for ease of access to the hull. The truck at the left is a FWD Model B three-ton truck, one of 15,000 delivered to the army.
The next major production vehicle was the M1917 light tank, a US-produced version of the French Renault FT light tank. The design was little changed from the French version except that the Renault engine was replaced by a Buda HU four-cylinder petrol engine.
Complications that delayed production were the conversion of the French metric measurements to the Imperial system used by the United States and the need to adapt the hand-fitted assembly of the French tank to massproduction methods. It should be noted that the design of the Renault FT set the concept for most future tank designs – driver in the front of the hull, commander and armament in a rotating turret in the centre hull, and the engine and drive system in the rear.
TURRET DESIGNS
Three turret designs had been used on the FT and the US Army chose the Berliet turret, comprised of eight riveted flat plates, rather than the cast and rolled Renault or Giroud turrets. The turret front could mount either the .30 Marlin (later, .30 Browning M1919) or the M1916 37mm short tank gun. The suspension used both coil and leaf springs. Some suspension components were altered from wood to steel for better durability. Initial contracts called for 4440 M1917 light tanks, but with the end of the war, this was reduced to 950 examples, built by three companies – 526 with the .30 machine gun, 374 with the M1916 37mm gun and 50 signal tanks with a fixed superstructure, the latter used for only a few years. The M1917 light tanks were used well into the 1930s, many of them being supplied to Canada for training purposes.
Initially after the end of the Great War, restricted budgets limited US armour activities to upgrading the M1917 light tanks. Studies by the US Army after the end of the Great War led to the conclusion that a new fast medium tank was needed, and it was not until 1922 that the Chief of Ordnance requested from the infantry specifications for a new light tank. The specification was ready weeks later and required a 37mm main gun and a .30 (7.62mm) machine gun, both operated by one person. The armour was to be proof against .30 armour-piercing (AP) bullets and a speed of 2-12 mph (3-17 km/h) with a range of 50 miles (80.5 km). The tank had to be less than five tons and suitable to be transported on a heavy truck.