Key point: The P-38 was a forerunner of modern multi-role fighters.
In 1937, the U.S. Army Air Corp called for proposals for an interceptor capable of flying 360 miles-per-hour and climbing rapidly to high altitudes. Kelly Johnson, designer at Lockheed—then a small company without major prior military contracts—calculated only a twin-engine fighter could meet such parameters.
Johnson’s winning submission stood apart from the crowd: instead of a traditional fuselage, the twin Allison V-1710 liquid-cooled engines on his YP-38 connected at the tail via long booms. The pilot sat in a slender central pod from which bristled four .50-caliber machine guns and a 20-millimeter Hispano cannon. (A bulkier 37-millimeter Oldsmobile cannon on early models was quickly ditched.) Turbochargers mounted atop the engines enabled rapid climb-rates, increased its service ceiling, and even muffled the engines, with contra-rotating propellers to reduce torque.
The P-38 could indeed fly fast—maxing at 395 miles-per-hour—and far (at slower speeds), up to 1,100 miles. However, the fighter’s unconventional configuration had its downsides, notably an infamous tendency for the controls to lock up in steep, high-speed dives, with often fatal results. The engines were finicky and required high levels of pilot training that were frequently lacking. The cockpit was poorly temperature-regulated—freezing at high altitude, excessively hot in tropical climates.
These flaws led the British Royal Air Force to cancel its Lightning order—only for it to be subsequently picked up by America after the Pearl Harbor attack. Uniquely amongst U.S. fighters, it remained in production throughout the entire war, with 10,000 built.
Each P-38 cost around $120-100,000, twice the price of most U.S. single-engine fighters. However, the P-38’s long range and heavy payload—up to 3,000 pounds of bombs and rockets—meant it could perform missions early-war single-engine types simply couldn’t.