Definition
The M2 medium tank was a United States Army prototype medium‑tank series developed in the mid‑1930s. It served primarily as an experimental platform for testing chassis, suspension, and armament concepts that later influenced the production models such as the M3 Lee and M4 Sherman.
Overview
Development of the M2 medium tank began in 1935 under the direction of the U.S. Ordnance Department, which sought a vehicle that could bridge the gap between the earlier M1 and M2 light tanks and a future, more heavily armed and armored medium tank. Only a small number of prototypes and limited‑production vehicles were built (approximately 20–30 units), and the type never entered front‑line service. The M2 medium tank was used mainly for training, evaluation, and as a testbed for new components. Its design experience contributed to the adoption of the Vertical Volute Spring Suspension (VVSS) and the incorporation of a 37 mm main gun in subsequent U.S. medium tanks.
Etymology / Origin
The designation follows the U.S. Army’s ordnance nomenclature: “M” stands for “Model” and the numeral “2” indicates the second major medium‑tank design accepted by the Ordnance Department. The term “medium tank” distinguished it from the lighter “combat car” and “light tank” categories employed by the Army during the interwar period.
Characteristics
| Feature | Details |
|---|---|
| Crew | 5 (commander, gunner, loader, driver, hull machine‑gunner) |
| Weight | Approximately 20 tons (varied slightly between prototype versions) |
| Armament | Early prototypes mounted only machine guns (two .30 cal Browning M1919s and one .50 cal M2). Later variants were fitted with a 37 mm M1 main gun together with the .50 cal and .30 cal machine guns. |
| Armor | Maximum plate thickness about 12–13 mm (0.5 in), sloped in limited areas; overall protection was considered light for a medium tank. |
| Engine | Four‑cylinder, gasoline‑powered Continental R‑670 radial engine delivering roughly 250 hp. |
| Power‑to‑weight ratio | Approx. 12.5 hp/ton. |
| Suspension | Early models employed a leaf‑spring system; later prototypes incorporated the Vertical Volute Spring Suspension (VVSS) that would become standard on later U.S. medium tanks. |
| Maximum speed | 15–18 mph (24–29 km/h) on road, depending on engine and transmission setup. |
| Operational range | About 100 mi (160 km) on road. |
| Production status | Prototype/limited production; never mass‑produced or employed in combat. |
Note: Exact specifications varied among the few prototype batches, and some details remain uncertain due to limited surviving documentation. Where definitive data are lacking, the above figures represent the most commonly reported values in available sources.
Related Topics
- M1 combat car – an early U.S. armored vehicle that informed later medium‑tank designs.
- M2 light tank – a contemporaneous light‑tank series sharing some components with the M2 medium tank.
- M3 Lee (Medium) tank – the first U.S. medium tank produced in quantity, incorporating lessons from the M2 prototypes.
- M4 Sherman – the principal U.S. medium tank of World War II, whose development lineage traces back to the M2.
- Vertical Volute Spring Suspension (VVSS) – a suspension system first tested on the M2 and widely used on later U.S. tanks.
- U.S. armored vehicle development (interwar period) – the broader context of experimentation and doctrine shaping American tank design in the 1930s.