1944 In 1942, automobile manufacturer General Motors converted several of its east coast factories to aircraft production under the name Eastern Aircraft Division. Eastern received contracts to build F4F-4 “Wildcat” fighters and TBF-1 “Avenger” torpedo planes, allowing Grumman to gradually reconcentrate its energies on the new, urgently-needed F6F “Hellcat” fighter.

The GM F4F-4s, redesignated FM-1s, had only four .50 caliber machine guns, but were otherwise little changed from the original model. Well over a thousand FM-1 fighters were delivered in 1942-43, including some three hundred for the British Royal Navy.

Meanwhile, Grumman had prototyped a new “Wildcat” under the designation XF4F-8, which was to be produced by Eastern Aircraft as the FM-2. With lightened structure and a more powerful Wright R-1820 radial engine, the FM-2 was notably quicker, faster climbing, longer ranged and more maneuverable than its predecessor. To help control the increased power, the new plane had a distinctive, taller vertical tail. All-in-all, it was a great improvement, and more than four thousand FM-2s were built in 1943-45.