Fairchild entered the aircraft engine business in 1925 with the formation of the Fairchild-Caminez engine corporation of Farmingdale, New York. Initially a manufacturer of radial engines designed by Harold Caminez, whose earlier career was at the U.S. Army’s McCook Field, Fairchild later became a successful manufacturer of air-cooled in-line aircraft engines. Built by the Ranger Engineering Division of Fairchild Engine and Airplane Corporation, the L-440-1 completed its 150-hour military type test in June 1939, thereby making the engine eligible for all primary trainer aircraft competitions. The civilian Model 6-440-C2 followed and was certificated in July 1939.

The L-440-1 powered the Fairchild PT-19/A/B trainer and Waco XPG-2/A/B and PG-2A powered gliders. Other military aircraft powered by the Model L-440 series were the Fairchild PT-26 and UC-61. Among the civilian aircraft powered by the 6-440 series were the Fairchild 24R46 and Grumman Widgeon G-44-A aircraft.