***image1***In the mid-1930s, the basic Army Air Corps doctrine focused on strategic bombing and the belief that the “bomber would always get through,” even without fighter escort.
At the same time, a few in the Air Corps turned their eyes toward defending against enemy bombers, and in 1934 the new Bell Aircraft company offered the Air Corps a “heavily armed superfighter capable of destroying bombers,” the XFM-1 (experimental fighter, multiplace) Aircuda.
The XFM-1 was a twin engine, with a crew of five and the incredibly heavy forward firing armament of two 37 mm M4 cannon and two .50 caliber machine guns. This was ten times the firepower of the normal fighter of the time, which carried two .30 caliber machine guns.
The XFM-1’s engines were mounted on the wing in the rear of long nacelles, and in the front of each nacelle was one cannon and one machine gun. Inside the nacelle was a loader whose job was to manually feed the cannon. The cannon were essentially fixed forward firing, aimed by a gunner in the main fuselage. The later FM-1A had tricycle landing gear, a first for an Air Corps aircraft.
The XFM-1 showed some potential and thirteen were eventually built, but it proved to be underpowered and its size, complexity and cost – one Aircuda was twice the price of a B-17 – led to its demise.
There were other problems, too. Bailing out into the pusher propellers, especially for the loaders, was an unattractive prospect. Probably more important was that the Air Corps was focused on strategic bombers that were intended to be almost invincible, so buying an aircraft that could shoot them down seemed to be an odd idea.
Ironically, the theory of the heavily armed “bomber destroyer” was validated a few years later when the US began sending its B-17s into Germany unescorted.
The German Luftwaffe upgunned their twin-engine fighters with large cannon comparable to the Aircuda’s, and they wreaked terrible destruction on the American bomber formations for almost half a year until the Eighth Air Force was able to provide long range fighter escort.