Lycoming ALF 502
   HOME

TheInfoList



OR:

The Lycoming ALF 502/LF 507 (later Honeywell ALF 502/LF 507) is a
geared turbofan The geared turbofan is a type of turbofan aircraft engine with a planetary gearbox between the low pressure compressor / turbine and the fan, enabling each to spin at its optimum speed. The benefit of the design is lower fuel consumption and m ...
engine An engine or motor is a machine designed to convert one or more forms of energy into mechanical energy. Available energy sources include potential energy (e.g. energy of the Earth's gravitational field as exploited in hydroelectric power ge ...
produced by Lycoming Engines,
AlliedSignal AlliedSignal, Inc. was an American aerospace, automotive and engineering company, created through the 1985 merger of Allied Corp. and The Signal Companies. It purchased Honeywell for $14.8 billion in 1999, and adopted the Honeywell name and iden ...
, and
Honeywell Aerospace Honeywell Aerospace Technologies is a manufacturer of aircraft engines and avionics, as well as a producer of auxiliary power units (APUs) and other aviation products. Headquartered in Phoenix, Arizona, it is a division of the Honeywell Intern ...
. The U.S. military designation for the ALF 502 is YF102.


Development

In mid-1970, Avco Lycoming was advertising two
Lycoming T55 The Honeywell T55 (formerly Lycoming; company designation LTC-4) is a turboshaft engine used on American helicopters and Fixed-wing aircraft, fixed-wing aircraft (in turboprop form) since the 1950s, and in H1 Unlimited, unlimited hydroplanes sinc ...
-derived engines, an LTC4B-12 turboprop and an ALF 502A turbofan, as possible powerplants for the U.S. Air Force's A-X
close air support Close air support (CAS) is defined as aerial warfare actions—often air-to-ground actions such as strafes or airstrikes—by military aircraft against hostile targets in close proximity to friendly forces. A form of fire support, CAS requires ...
aircraft program.
Northrop Corporation Northrop Corporation was an American aircraft manufacturer from its formation in 1939 until its 1994 merger with Grumman to form Northrop Grumman. The company is known for its development of the flying wing design, most successfully the B-2 Spiri ...
signed a contract with Avco Lycoming to use the ALF 502A for its entry into the A-X competition, the Northrop YA-9, in January 1971. The engine was given a United States military aircraft engine designation of YF102-LD-100. Six YF102 engines were built for the YA-9. The thrust engines powered the A-9A prototypes for seven months of flight tests in 1972, recording 238 flights and 652 flight hours. These engines were later reused in the C-8A Quiet Short-Haul Research Aircraft (QSRA). The commercial ALF 502D engine was developed from the military YF102 in 1971. Its derated engine had just one booster compressor stage instead of the YF102's two stages, and operated under a lower turbine temperature to improve reliability. The ALF 502D powered the Dassault Falcon 30 prototype from May 1973 into 1975, logging 270 flight hours until Dassault discontinued development of the aircraft model. The ALF 502D was also chosen for the LearStar 600 executive transport aircraft, which eventually became the Canadair CL-600 Challenger. The CL-600 Challenger first flew in November 1978 and was powered by the ALF 502L-2, ALF 502L-2A, and ALF 502L-3 variants. The ALF 502R-3 variant initially powered the quad-engine
British Aerospace 146 The British Aerospace 146 (also BAe 146) is a short-haul and regional airliner that was manufactured in the United Kingdom by British Aerospace, later part of BAE Systems. Production ran from 1983 until 2001. Avro International Aerospace manufa ...
, which entered service in 1983 and became the ALF 502's biggest customer. A total of 1,019 ALF 502 engines of all variants were produced. The LF 507 series based on the ALF 502R was announced in September 1988. The series initially consisted of the hydromechanically controlled LF 507-1H and the
FADEC A full authority digital engine (or electronics) control (FADEC) is a system consisting of a digital computer, called an "electronic engine controller" (EEC) or " engine control unit" (ECU), and its related accessories that control all aspects of a ...
-controlled LF 507-1F, both offering of thrust. Both variants were used on the Avro RJ update of the BAe 146, and the LF 507-1F was also used on the BAe 146. 818 LF 507 engines were produced. In 2020, Honeywell sold the type certificate to CFS Aeroproducts Inc. (Arizona), a subsidiary of MRO provider CFS Aeroproducts Ltd (UK), then transferred in January 2021.


Proposed variants

In 1972, Lycoming and
NASA The National Aeronautics and Space Administration (NASA ) is an independent agencies of the United States government, independent agency of the federal government of the United States, US federal government responsible for the United States ...
published a study describing the ALF504, a 12.5 bypass ratio engine producing of sea-level thrust at a specific fuel consumption of and a fan tip diameter of . Lycoming announced its LF500 family of turbofans in September 1988, starting with the LF507-1H and LF507-1F, which were certificated in October 1991 and March 1992, respectively. In June 1992, the company outlined improvements to the LF500 family's core, which included a wide-chord fan to move more air, uprated fan
gearbox A transmission (also called a gearbox) is a mechanical device invented by Louis Renault (who founded Renault) which uses a gear set—two or more gears working together—to change the speed, direction of rotation, or torque multiplication/r ...
, three-stage power
turbine A turbine ( or ) (from the Greek , ''tyrbē'', or Latin ''turbo'', meaning vortex) is a rotary mechanical device that extracts energy from a fluid flow and converts it into useful work. The work produced can be used for generating electrical ...
(an increase from two stages), more lighter-weight
composite materials A composite or composite material (also composition material) is a material which is produced from two or more constituent materials. These constituent materials have notably dissimilar chemical or physical properties and are merged to create a ...
, increased diameter in the first three stages of the
axial compressor An axial compressor is a gas compressor that can continuously pressurize gases. It is a rotating, airfoil-based compressor in which the gas or working fluid principally flows parallel to the axis of rotation, or axially. This differs from other ...
to increase airflow by 17 percent, an improved impeller (centrifugal compressor) with lean-back vanes, a 16-lobe forced exhaust mixer to reduce noise and specific fuel consumption (SFC), an advanced
combustor A combustor is a component or area of a gas turbine, ramjet, or scramjet engine where combustion takes place. It is also known as a burner, burner can, combustion chamber or flame holder. In a gas turbine engine, the ''combustor'' or combustion ...
, and a temperature margin increase of in the turbine. Lycoming introduced the 500 Series of common core engines of turboprops and turbofans in February 1994 as a derivative of the LF507 to power regional aircraft in the late 1990s. A turboprop version also was planned for the European Future Large Aircraft military transport (which would eventually become the
Airbus A400M The Airbus A400M AtlasNamed after the Atlas (mythology), Greek mythological figure. is a European four-engine turboprop military transport aircraft. It was designed by Airbus Military, now Airbus Defence and Space, as a tactical airlifter with ...
). AlliedSignal, which took over Lycoming in October 1994, demonstration tested the common core in December; the core was capable of producing of
thrust Thrust is a reaction force described quantitatively by Newton's third law. When a system expels or accelerates mass in one direction, the accelerated mass will cause a force of equal magnitude but opposite direction to be applied to that ...
. After losing the competition to power the de Havilland Dash 8-400 regional turboprop, AlliedSignal abandoned the common core effort in July 1995.


Design

The ALF502 is a high bypass turbofan with geared fan, axial-centrifugal flow high pressure compressor, reverse flow annular combustor, two-stage high pressure turbine, two-stage low pressure turbine.


Variants

; ALF502R-3 (single-stage LP compressor) * ALF502R-4: R-3 with higher thrust * ALF502R-5: R-4 with improved first-stage and second-stage turbine nozzle assemblies * ALF502R-3A: R-3 with gas producer turbine improvements, but operated at higher thrust ; ALF502L (two-stage LP compressor) * ALF502L-2: L with fan blade modification for increased altitude performance * ALF502L-3: L-2 with turbine improvements and automatic power reserve features * ALF502L-2A: L-2 with gas producer turbine improvements and automatic power reserve features * ALF502L-2C: L-2A without automatic power reserve * ALF502R-6: L-2C with R-5 accessory gearbox * LF507-1H: R-6 with lower, flat-rated thrust * LF507-1F: 507-1H with a single-channel FADEC with hydromechanical backup


Proposed Common Core engines

(LF500 family/Lycoming 500 Series/AlliedSignal AS800) * LF508B2: A engine offered for the quad-turbofan powered, 120-seat British Aerospace Regional JetLiner (formerly
BAe 146 The British Aerospace 146 (also BAe 146) is a short-haul and regional airliner that was manufactured in the United Kingdom by British Aerospace, later part of BAE Systems. Production ran from 1983 until 2001. Avro International Aerospace manu ...
) in 1992 * LF509: A turbofan engine for the Avro RJ100 * LF511D: An turbofan with a wide-chord fan, a three-stage power turbine, and a three-stage low-pressure booster compressor * LF512 / LF514: Additional turbofan engines of thrust, possibly for
Avro Avro (an initialism of the founder's name) was a British aircraft manufacturer. Its designs include the Avro 504, used as a trainer in the First World War, the Avro Lancaster, one of the pre-eminent bombers of the Second World War, and the d ...
's proposed 120-seat RJX twin airliner or for a stretched version of the 50-seat Canadair Regional Jet * LF518: An turbofan variant. * LP512: Turboprop engines targeted for the de Havilland Dash 8-400 and the proposed ATR 82, having an initial power output of but with uprate capability to


Applications

;YF102 * Northrop YA-9 * C-8A Quiet Short-Haul Research Aircraft ;ALF 502 * Bombardier Challenger 600: early CL-600 (1A11) series, 81 built from 1978 to 1982 *
British Aerospace 146 The British Aerospace 146 (also BAe 146) is a short-haul and regional airliner that was manufactured in the United Kingdom by British Aerospace, later part of BAE Systems. Production ran from 1983 until 2001. Avro International Aerospace manufa ...
* Dassault Falcon 30 (prototype) ;LF 507 * Avro RJ *
British Aerospace 146 The British Aerospace 146 (also BAe 146) is a short-haul and regional airliner that was manufactured in the United Kingdom by British Aerospace, later part of BAE Systems. Production ran from 1983 until 2001. Avro International Aerospace manufa ...
*
Yakovlev Yak-40 The Yakovlev Yak-40 (; NATO reporting name: Codling) is a regional jet designed in Soviet Union by Yakovlev. The trijet's maiden flight was in 1966, and it was in production from 1967 to 1981. It was introduced to service in 1968, with export mo ...
TL (proposed reengine)


Specifications


See also


Notes


References


Further reading

* *


External links


Honeywell propulsion products page

Technical details from Swiss International Air Lines
{{USAF gas turbine engines Geared turbofan engines High-bypass turbofan engines Honeywell ALF 502 Mixed-compressor gas turbines 1980s turbofan engines