The M-3 Stuart (Honey) and M-5 Series Light Tanks evolved from the M-1 Combat Car and the M-2 Light Tank that were developed in the early 1930s after Chief of Staff General Douglas MacArthur mechanized the United States Army.
The M-1 and M-2 were the first American-designed and American-built tanks to reach production and be deployed with American armed forces. The M-1 was only equipped with machine guns, but the M-2, in its A2 variation, mounted a 37mm gun in a traversing turret. The M-2's main armor was less than 1 inch thick. The M-2 did not see combat but was used by the United States and Great Britain as a training tank.
The events of 1939-1940 were studied carefully by American army commanders, especially those in mechanized and armored units. Suggestions for improving the M-2 poured into Rock Island Arsenal, Illinois, where all tank development was concentrated at that time. Increased armor protection was the main demand. To increase armored protection, a new suspension system and a more powerful engine were required.
A new design was begun -- the Light Tank T-3. ("T" designations indicate experimental and developmental designs only.) Maximum armor protection was increased to nearly 1.5 inches; track-ground contact was increased by pivoting the rear trailing wheel on an arm, or idler; more armor was added to the engine compartment to protect against aircraft attack; and a single-welded turret was installed.
The M-2's Continental W-670, 250-horsepower gasoline engine was used in the M-3. The M-3 carried a crew of four -- commander, gunner, driver, and co-driver -- inside a cramped hull and turret. Tests were successful, and the new M-3 tank was put into production in March 1941.
Almost immediately, changes were introduced. A new, lighter cast-and-welded turret replaced the riveted turret. Tests showed that rivets tended to pop when the turret was hit by gunfire.
Early in 1941 a third turret design was introduced into production. This turret was cast-and-welded and also had rounded surfaces to decrease the chance of penetration.
In mid-1941 a gyrostabilizer was added to the 37mm main gun, and in late 1941 extra fuel tanks were added to the outside hull to increase range. The extra fuel tanks could be jettisoned at will.
Later variations included an all-welded hull construction and the substitution of a diesel engine for the scarce gasoline engine. The final major variation, the M-3A1, was standardized for production in August 1941 and incorporated all changes made to date.
The British obtained the M-3 under the auspices of the Lend Lease program and immediately put it to work in the Western Desert. Officially designated the M-3 Stuart by the British, it was better known as the "Honey" because, even though it was under-gunned and under-armored, the British liked its speed and agility.
Its speed also made it useful for reconnaissance. Beginning in September 1942 on Guadalcanal in the Solomon Islands campaign, the M-3 Stuart saw service throughout the Pacific with the Marines and the Army. By the time production ended in 1943, 13,859 had been manufactured.
See the next page to read about the M-5 Light Tank.