In the end of the 1920-s the American Army strictly following the method of using combat vehicles conventional for those times assigned a technical task to develop a light tank of infantry support. This new vehicle was meant to replace out-of-date 6-tonn vehicles and 3-tonn “fords” which were no longer satisfactory on the point of speed and armour. The Cunningham Company was the one who showed great interest in that. They were well-known for their chain-track tractors. Having studied the experience of their foreign colleagues (first of all British) the American engineers came to a conclusion that the classical arrangement of a tank is far from ideal. A light tank Cunningham T1 appeared after they have combined their ideas with the ideas of their foreign colleagues.
The light tank T1 development started in 1926 and its prototype was sent to being tested in the beginning of the next year. “The tractor past” left its traces. The tank got the chassis which had been poorly adapted to overcoming the obstacles appearing on battlefields wounded by mines and shells (for example a 2-metre ditch was an unsurpassable barrier). However in production it was highly technological. The chassis consisted of 16 road wheels of small diameter (8 for each board) with coil springs amortization. There were 6 carrier rollers, guiding front wheels and leading back wheels. Namely owing to innovations in running gear this armed “tractor” could speed up to 30 km/h.
The vehicle weight gained 7198kg. It was protected by welded and riveted construction of mill-rolled armour plate 10-15 mm wide. It provided protection from rifle bullets (without a steel pit) from 100 meters distance.
In the front part of the body there was an engine-transmission section where a gasoline engine Cunningham with 8 cylinders of 132 hp in 2600 was placed. The gas tank was for 221, 5 litres and mechanic transmission with a 4-gear gearbox. The manufacturer engine starting was held with the help of an electric starter. 190 litres of gasoline was enough to move 120 on a road.
Combined with the combat section, the section of operation was close to the after part of the tank. The Т1 crew consisted of 2 persons: a driver and a commanding officer (who was also a shooter). Because of the lack of room the commanding officer was forced to basically stand on their colleague’s shoulders.
The armament was mounted in the cylindrical turret of the tank and consisted of a 37-mm gun M5 L/50 (ammunition: 104 shells or 80 shells according to other reports) and coaxial 7.62-mm Browning M1919A4 (3000 rounds) machine gun. Despite the small calibre the initial velocity of the firing shell gained 777 m/s and that allowed for penetrating any enemy armoured vehicle at range up to 1000 meters.
This tank is also known as the armoured vehicle that stayed in service less than any other engineering technique: from January 4, 1928 – March 30, 1928. That is a little less than three months. Therefore, in short terms it was returned for the improvement. The following prototype Т1Е1 had improved hull design and in 1928 the Army accepted it into service under the designation M1. T1E2 modification was equipped with more powerful engine, modified turret (without inclined armour plating) and up-armoured frontal armour plating. Later this tank was re-equipped with 37-mm long-barrel gun. In fact, the era of American light tanks began.