The Honeywell TFE731 is a geared turbofan family developed specifically for business aviation. The original TFE731-2 was certified in August 1972 and entered production the following month. Its lower fuel consumption and noise helped business jets undertake longer flights while meeting increasingly restrictive airport requirements.[1]
Programme origins
The concept emerged in the late 1960s from a requirement for a reliable engine supporting coast-to-coast journeys without refuelling. Engineers adapted two-spool technology from the TSCP700 auxiliary power unit used in the Douglas DC-10. The resulting TFE731-2 produced 3,500 pounds of takeoff thrust, with Learjet and Dassault among the launch customers.[1]
Expanding applications
The engine was subsequently adopted by manufacturers including Cessna, Lockheed and Israel Aerospace Industries. It also powered military trainers such as the CASA C-101 and AIDC AT-3. That expansion gave the family a broader role than its business-jet origins, while later versions remained associated with aircraft such as the Falcon 900, Learjet 70/75 and Gulfstream G150.[1][2]
Later engine changes
Development continued through changes to the core, low-pressure system and controls. Honeywell describes seventy changes incorporated in the TFE731-50R, including a digital electronic engine control and a complete nacelle and thrust-reverser system. The changes increased temperature margins and improved the way available thrust decreased with altitude compared with the TFE731-5BR.[2]
Performance evolution
The programme expanded from the original 3,500-pound output to the approximately 5,000-pound thrust class. The -50R improvements also addressed fuel consumption: Honeywell reported up to an eight-percent specific-fuel-consumption improvement over the -5BR, depending on altitude. Such changes show how a mature engine family could gain useful capability through coordinated aerodynamic, thermal and control-system development.[2]