In July 1952, Lycoming was awarded a contract by the Air Force Air Materiel Command to develop a free-turbine turboshaft engine designated LTC1 (military designation T53-L-1). The first production engine was delivered in 1959.
The T53's front-drive, concentric-shaft arrangement set a widely accepted U.S. design standard for turboshaft engines, and gave Lycoming its start in the aircraft gas turbine business. It was a key technology contributing to expansion of Army aviation's air-mobility during the Viet Nam War. Airframe applications were the Bell UH-1 Iroquois (Huey) and AH-1 HueyCobra helicopters and Grumman OV-1 Mohawk aircraft.
Development of the T53-L-13 (LTC1K-4) series began in 1959, and the engine first ran in 1960. Qualified in June 1966, the first production engine was delivered in August 1966. The L-13 series powered the Bell HU-1C/D/H Iroquois and the Bell AH-1G HueyCobra. This Lycoming LTC1K-4 (Air Force Model No. T53L1B) turboshaft engine powered a U.S. Air Force Kaman HH-43B helicopter.
This object is not on display at the National Air and Space Museum. It is either on loan or in storage.