A turbofan or fanjet is a type of airbreathing jet engine that is widely used in aircraft propulsion. The word "turbofan" is a combination of the preceding generation engine technology of the turbojet, and a reference to the additional fan stage added. It consists of a gas turbine engine which achieves mechanical energy from combustion, and a ducted fan that uses the mechanical energy from the gas turbine to force air rearwards. Thus, whereas all the air taken in by a turbojet passes through the combustion chamber and turbines, in a turbofan some of that air bypasses these components. A turbofan thus can be thought of as a turbojet being used to drive a ducted fan, with both of these contributing to the thrust.
The SNECMA M53 is an afterburning turbofan engine developed for the Dassault Mirage 2000 fighter by Snecma. The engine is in service with different air forces, including the latest Mirage 2000-5 and 2000-9 multirole fighters.
The General Electric TF34 is an American military turbofan engine used on the A-10 Thunderbolt II, S-3 Viking and RQ-170 Sentinel.
A jet engine performs by converting fuel into thrust. How well it performs is an indication of what proportion of its fuel goes to waste. It transfers heat from burning fuel to air passing through the engine. In doing so it produces thrust work when propelling a vehicle but a lot of the fuel is wasted and only appears as heat. Propulsion engineers aim to minimize the degradation of fuel energy into unusable thermal energy. Increased emphasis on performance improvements for commercial airliners came in the 1970s from the rising cost of fuel.
The Rolls-Royce RB.401 was a British two-spool business jet engine which Rolls-Royce started to develop in the mid-1970s as a replacement for the Viper. RB.401-06 prototype engines were already being manufactured when a decision to develop the higher thrust RB.401-07 was taken.
The Pratt & Whitney Canada PW300 series is a family of turbofan jet engines developed by Pratt & Whitney Canada specifically for business jet applications.
The Garrett TFE731 is a family of geared turbofan engines commonly used on business jet aircraft. Garrett AiResearch originally designed and built the engine, which due to mergers was later produced by AlliedSignal and now Honeywell Aerospace.
The CFE CFE738 is a small turbofan engine aimed at the business/commuter jet market manufactured by the CFE Company, and is used on the Dassault Falcon 2000.
The NK-8 was a low-bypass turbofan engine built by the Kuznetsov Design Bureau, in the 90 kN (20,000 lbf) thrust class. It powered production models of the Ilyushin Il-62 and the Tupolev Tu-154A and B models.
The Lycoming ALF 502/LF 507 is a geared turbofan engine produced by Lycoming Engines, AlliedSignal, and then Honeywell Aerospace. The U.S. military designation for the ALF 502 is YF102.
The Safran Silvercrest is a French turbofan under development by Safran Aircraft Engines.
The SNECMA Turbomeca Larzac is a military turbofan manufactured by GRTS, a consortium between the two French companies, SNECMA and Turbomeca. Its main application was on the Dassault/Dornier Alpha Jet.
The Honeywell/ITEC F124 is a low-bypass turbofan engine derived from the civilian Honeywell TFE731. The F125 is an afterburning version of the engine. The engine began development in the late 1970s for the Republic of China (Taiwan) Air Force AIDC F-CK Indigenous Defence Fighter (IDF), and it first ran in 1979. The F124/F125 engine has since been proposed for use on other aircraft, such as the T-45 Goshawk and the SEPECAT Jaguar, and currently powers the Aero L-159 Alca and the Alenia Aermacchi M-346. The F124 has a rather unusual design for a two spool gas turbine engine, using both axial and centrifugal compressors in its high-pressure compressor. There are currently only three production variants of the engine, although several more have been proposed throughout its lifespan.
The Soloviev D-20P, built by the Soloviev Design Bureau, was a low-bypass turbofan engine rated at 52.9 kN (11,900 lbf) thrust used on the Tupolev Tu-124. Elements of the design were used in the development of the larger Soloviev D-30 family of low and medium bypass engines.
The Garrett F109 was a small turbofan engine developed for the Fairchild T-46 by Garrett AiResearch. With the United States Air Force's cancellation of the T-46 program in 1986, further development of the engine ceased, and with it the civil TFE109 version.
The General Electric CF700 is an aft-fan turbofan development of the CJ610 turbojet. The fan blades are an extension of the low-pressure turbine blades.
The Garrett TPF351 is a turboprop engine designed by Garrett Engine Division of AlliedSignal Aerospace Company. Initiated by Garrett in October 1987, the TPF351-20 engine was selected by Embraer to power the Embraer/FMA CBA 123 Vector, a high-speed commuter "pusher" aircraft. It was first tested on May 19, 1989 and then ground tested and flight tested on a Boeing 720 on July 9, 1990. The first prototype CBA 123 was tested on July 18, 1990, followed by a flight to the Farnborough Air Show in September of the same year. Both programs were cancelled in 1992, when the TPF351 was nine months from engine certification.
The Turbomeca Astafan is a single-spool, variable-pitch turbofan engine developed from the Turbomeca Astazou. Despite successful flight-testing, an efficient, quiet and clean design and some commercial interest, the Astafan never entered series production. The engines were only flown on the Fouga 90 prototype and Turbomeca's two test aircraft.
The Pratt & Whitney Canada PW800 is a series of turbofan engines in the 10,000–20,000 lbf (44–89 kN) thrust class, manufactured by Pratt & Whitney Canada. Intended for the regional jet and business jet market, the gear-less PW800 shares a common core with the larger, geared PW1000G. The first variants were certified on February 15, 2015, to power the new Gulfstream G500/G600. After that it has been certified also for the Dassault Falcon 6X in 2021.
The Turbomeca Aspin was a small French turbofan engine produced by Turbomeca in the early 1950s. This geared turbofan design was the first turbofan to fly, powering the Fouga Gemeaux test-bed aircraft on 2 January 1952.
