{{short description|High-bypass turbofan aircraft engine}} {{about|the American turbofan engine|the Chinese rocket engine|YF-102 (rocket engine)}} {{infobox aero engine |name= ALF 502/LF 507 |image= File:ALF502.JPG |caption= ALF 502 removed from a Bombardier Challenger 600-1A11 |engine_type= [[Geared turbofan|Geared]] [[turbofan]] |national_origin = United States |manufacturer= {{ubl | [[Lycoming Engines|Lycoming]] | [[AlliedSignal]] | [[Honeywell Aerospace]] }} |first_run= June 1971{{R|"LeyesFleming"|p=[{{GBurl|V0SnFt8JGokC|p=191}} 191]}} |major_applications= {{ubl | [[Bombardier Challenger 600]] | [[British Aerospace 146]] | [[Northrop YA-9]] }} |number_built = {{formatnum: {{#expr: 6 + 1019 + 818}} }} |developed_from = [[Lycoming T55]] |variants_with_their_own_articles = |developed_into = }} [[File:AJ-2 Savage test bed for Lycoming engines in flight.jpeg|thumb|The YF102-LD-100 was tested on an [[North American AJ Savage|AJ Savage]] in the early 1970s.]]
The '''Lycoming ALF 502/LF 507''' (later '''Honeywell ALF 502/LF 507''') is a [[geared turbofan]] [[Aircraft engine|engine]] produced by [[Lycoming Engines]], [[AlliedSignal]], and [[Honeywell Aerospace]]. The U.S. military designation for the ALF 502 is '''YF102'''.
==Development== In mid-1970, [[Avco]] [[Lycoming Engines|Lycoming]] was advertising two [[Lycoming T55]]-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]] aircraft program.<ref name="AFM197007">{{cite magazine |issn=0730-6784 |magazine=[[Air Force Magazine]] |title=Proven power, turbofan or turboprop, for any AX configuration |url={{GBurl|w-U9AQAAIAAJ|pg=RA6-PA45}} |publication-date=July 1970 |page=45 |author=Avco Lycoming Division |author-link=Avco Lycoming}}</ref> [[Northrop Corporation]] 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.{{R|"LeyesFleming"|p=[{{GBurl|V0SnFt8JGokC|p=190}} 190]}} Six YF102 engines were built for the YA-9. The {{cvt|7,500|lbf|kN}} thrust engines powered the A-9A prototypes for seven months of [[flight test]]s in 1972, recording 238 flights and 652 flight hours.<ref name="A-9A"/> 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 {{cvt|6,500|lbf|kN}} 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 {{cvt|7,500|lbf|kN}} ALF 502L-2, ALF 502L-2A, and ALF 502L-3 variants. The {{cvt|6,700|lbf|kN}} ALF 502R-3 variant initially powered the quad-engine [[British Aerospace 146]], 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]]-controlled LF 507-1F, both offering {{cvt|7,000|lbf|kN}} 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.{{R|"LeyesFleming"|pp=[{{GBurl|V0SnFt8JGokC|p=192}} 192]–[{{GBurl|V0SnFt8JGokC|p=199}} 199], [{{GBurl|V0SnFt8JGokC|p=203}} 203]}} 818 LF 507 engines were produced.<ref name="FI20040816">{{cite magazine |issn=0015-3710 |magazine=[[Flight International]] |title=Uncontained failure dogs Honeywell LF507 engine |url=https://www.flightglobal.com/uncontained-failure-dogs-honeywell-lf507-engine/56071.article |date=August 16, 2004 |first1=David |last1=Learmount |first2=Guy |last2=Norris |access-date=January 30, 2022}}</ref>
In 2020, Honeywell sold the type certificate to CFS Aeroproducts Inc. (Arizona), a subsidiary of [[Aircraft maintenance|MRO provider]] CFS Aeroproducts Ltd (UK), then transferred in January 2021.<ref>{{cite press release |url= https://www.atp.com/cfs-aeroproducts-inc-chooses-atp-as-exclusive-partner-for-alf502-and-lf507-series-engine-publications/ |title= CFS Aeroproducts Inc. Chooses ATP as Exclusive Partner for ALF502 and LF507 Series Engine Publications |date= July 27, 2021 |publisher= ATP}}</ref>
===Proposed variants=== In 1972, Lycoming and [[NASA]] published a study describing the ALF504, a 12.5 bypass ratio engine producing {{cvt|8,370|lbf|kgf kN}} of sea-level thrust at a [[Thrust-specific fuel consumption|specific fuel consumption]] of {{cvt|0.302|tsfc}} and a fan tip diameter of {{cvt|48.0|in}}.<ref name="NASA19730004744"/>
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.{{R|"LeyesFleming"|pp=[{{GBurl|V0SnFt8JGokC|p=198}} 198]}} 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]], three-stage power [[turbine]] (an increase from two stages), more lighter-weight [[composite materials]], increased diameter in the first three stages of the [[axial compressor]] 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]], and a temperature margin increase of {{cvt|120|C|order=flip}} in the turbine.<ref name="FI19920617"/> 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.{{R|"LeyesFleming"|pp=[{{GBurl|V0SnFt8JGokC|p=198}} 198], [{{GBurl|V0SnFt8JGokC|p=199}} 199], [{{GBurl|V0SnFt8JGokC|p=200}} 200]}} A turboprop version also was planned for the European [[Future Large Aircraft]] military transport (which would eventually become the [[Airbus A400M]]). AlliedSignal, which took over Lycoming in October 1994,<ref name="AW19941107"/> demonstration tested the common core in December; the core was capable of producing {{cvt|20000|lbf|kN}} of [[thrust]].<ref name="CRAN19941226"/> After losing the competition to power the [[de Havilland Dash 8]]-400 regional turboprop, AlliedSignal abandoned the common core effort in July 1995.<ref name="FG19950711"/>
==Design== [[File:Australian Corporate Jet Centres (VH-JPQ) Canadair CL-600-1A11 Challenger 600 taxiing at Wagga Wagga Airport (3) (cropped).jpg|thumb|Honeywell ALF 502 on an early [[Challenger 600]]]]
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.<ref name="TCDS"/>
==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 {{cvt|35|kN|lbf|order=flip|adj=mid|thrust}} engine offered for the quad-turbofan powered, 120-seat British Aerospace Regional JetLiner (formerly [[BAe 146]]) in 1992<ref name="FI19920617"/> * LF509: A {{cvt|9000|lbf|kN|adj=mid|thrust}} turbofan engine for the [[Avro RJ100]]<ref name="CRAN19940718"/> * LF511D: An {{cvt|49|kN|lbf|order=flip|adj=mid|thrust}} turbofan with a {{cvt|1.09|m|in|order=flip|adj=mid|diameter}} wide-chord fan, a three-stage power turbine, and a three-stage low-pressure booster compressor<ref name="FI19920617"/> * LF512 / LF514: Additional turbofan engines of {{cvt|12000|–|14000|lbf|kN}} thrust, possibly for [[Avro]]'s proposed 120-seat RJX twin airliner or for a stretched version of the 50-seat [[Canadair Regional Jet]]<ref name="CRAN19940718"/> * LF518: An {{cvt|80|kN|lbf|order=flip}} turbofan variant.<ref name="Interavia199410p16"/> * LP512: Turboprop engines targeted for the [[de Havilland Dash 8]]-400 and the proposed [[ATR 72|ATR 82]], having an initial power output of {{cvt|7500|shp}} but with uprate capability to {{cvt|11000|shp}}{{R|"LeyesFleming"|p=[{{GBurl|V0SnFt8JGokC|p=200}} 200]}}
==Applications== [[File:BEL RJ1H OO-DWG 3nov14 LFBO-1.jpg|thumb|Lycoming LF 507s on a [[Brussels Airlines]] [[British Aerospace 146]].]]
;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]] * [[Dassault Falcon 30]] (prototype)
;LF 507 * [[Avro RJ]] * [[British Aerospace 146]] * [[Yakovlev Yak-40]]TL (proposed reengine)<ref name="ATW199210">{{cite magazine |issn=0002-2543 |magazine=[[Air Transport World]] |title=Russian deals at Farnborough |pages=36+ |publication-date=October 1992 |first1=J.A. |last1=Donoghue |first2=Robert W. |last2=Moorman |first3=Arthur |last3=Reed |first4=James P. |last4=Woolsey |volume=29 |number=10 |id={{Gale|A12736619}}}}</ref>
==Specifications==
{| class="wikitable" style="text-align: center;" |+ Type Certificate Data Sheet<ref name="TCDS"/> ! Variant ! ALF502R-3 ! ALF502R-4/5/3A ! ALF502L/L-2/L-3/L-2A/L-2C/R-6 ! LF507-1H/1F |- ! Configuration | colspan=12 |[[High bypass turbofan|High bypass]], [[Transmission (mechanics)|geared]] fan |- ! Fan diameter | colspan=4 | {{cvt|40.25|in|mm}}<ref name="specs"/> |- ![[Gear train|Gear ratio]] | colspan=4 | 2.3:1<ref name="FI19930825"/> |- ![[Bypass ratio]] | colspan=4 | 5.7:1 |- ![[Compressor]] | colspan=2 | 1 LP, 7-stage [[Axial compressor|axial]]<ref name="specs"/> + [[Centrifugal compressor|centrifugal]] HP | colspan=2 | 2 LP, 7-stage axial<ref name="specs"/> + centrifugal HP |- ![[Combustor]] | colspan=4 | Reverse flow [[Annular combustor|annular]] |- ![[Turbine]] | colspan=4 | Two-stage HP, two-stage LP |- ! Takeoff [[thrust]] | {{cvt|6,700|lbf|kN|abbr=on|lk=on}} | {{cvt|6,970|lbf|kN}} | {{cvt|7,500|lbf|kN}} | {{cvt|7,000|lbf|kN}} |- ! Length | colspan=2 | {{cvt|63.66|in|mm|abbr=on}} | colspan=2 | {{cvt|65.57|in|mm}} |- ! Height | colspan=2 | {{cvt|55.5|in|mm}} | colspan=2 | {{cvt|54.5|in|mm}} |- ! Width | colspan=2 | {{cvt|47.8|in|mm}} | colspan=2 | {{cvt|48.6|in|mm}} |- ! Weight {{efn|includes essential engine accessories but excludes starter, hydraulic pump, integrated drive generator and exhaust nozzle}} | colspan=2 | {{cvt|1,336|lb|kg}} | colspan=2 | {{cvt|1,375|lb|kg}} (1F: {{cvt|1,385|lb|kg}}) |- ! LP [[Revolutions per minute|rpm]] | colspan=4 | 7,184 - 7,374 |- ! HP rpm | colspan=4 | 19,280 - 19,760 |- ! [[Thrust specific fuel consumption|TSFC]] ([[Standard sea-level conditions|SLS]] [[International Standard Atmosphere|ISA]]) | colspan=4 | {{cvt|0.406|tsfc|abbr=on}}<ref name="specs"/> |- ![[Thrust-to-weight ratio|Thrust/weight]] | {{#expr:6700/1336round2}} | {{#expr:6970/1336round2}} | {{#expr:7500/1375round2}} | {{#expr:7000/1375round2}} |}
==See also== {{Aircontent |related= * [[Lycoming T55]] * [[Honeywell HTF7000]] (AS907), ALF502/LF507 successor |similar engines= * [[GE CF34]] * [[Pratt & Whitney Canada PW300]] * [[Rolls-Royce AE 3007]]
'''Geared turbofans''' * [[Garrett TFE731]] * [[Turbomeca Aspin]]/[[Turbomeca Astafan|Astafan]] * [[Rolls-Royce/SNECMA M45H|Rolls-Royce/SNECMA M45SD]] |lists= * [[List of aircraft engines]]
}}
==Notes== {{notelist}}
==References== {{Reflist|refs= <ref name="specs">{{cite web | title=ALF 502 turbofan engine |work=[[Honeywell Aerospace]] | url=http://www.honeywell.com/sites/portal?smap=aerospace&page=Propulsion_Engines3&theme=T5&catID=CDAB5CA0F-004C-6DBB-B50C-20859E156C16&id=H8D86112E-572B-E3ED-33CB-C2D8ED91628F&sel=1g | archive-url=https://web.archive.org/web/20120305232900/http://www.honeywell.com/sites/portal?smap=aerospace&page=Propulsion_Engines3&theme=T5&catID=CDAB5CA0F-004C-6DBB-B50C-20859E156C16&id=H8D86112E-572B-E3ED-33CB-C2D8ED91628F&sel=1g | url-status=dead | archive-date=March 5, 2012 | date=November 29, 2010 }}</ref> <ref name="TCDS">{{cite web |url=https://rgl.faa.gov/Regulatory_and_Guidance_Library/rgMakeModel.nsf/0/3f30606514a3b28086256bea006c249c/$FILE/e6ne.pdf |title=Type certificate data sheet E6NE |edition=15th |date=June 7, 2002 |publisher=Department of Transportation, [[Federal Aviation Administration]] (FAA) |access-date=July 25, 2020 |archive-date=April 19, 2022 |archive-url=https://web.archive.org/web/20220419142043/https://rgl.faa.gov/Regulatory_and_Guidance_Library/rgMakeModel.nsf/0/3f30606514a3b28086256bea006c249c/%24FILE/e6ne.pdf |url-status=dead }}</ref> <ref name="LeyesFleming">{{cite book |title=The history of North American small gas turbine aircraft engines |url={{GBurl|V0SnFt8JGokC|pg=frontcover}} |given1=Richard A., II |surname1=Leyes |given2=William A. |surname2=Fleming |year=1999 |publisher=[[National Air and Space Museum]] and [[American Institute of Aeronautics and Astronautics]] (AIAA) |location=Reston, VA |isbn=1-56347-332-1 |oclc=247550535}}</ref> <ref name="FG19950711">{{cite news |work=[[FlightGlobal]] |title=AlliedSignal plans turbine closure |url=https://www.flightglobal.com/alliedsignal-plans-turbine-closure/15488.article |date=July 11, 1995 |access-date=July 16, 2020}}</ref> <ref name="CRAN19941226">{{cite newsletter |issn=1040-5402 |work=Commuter Regional Airline News |title=AlliedSignal runs demo test on former Lycoming 'Common Core' engine |publication-date=December 26, 1994 |pages=6+ |volume=12 |number=50 |id={{Gale|A16362047}}}}</ref> <ref name="AW19941107">{{cite magazine |issn=0005-2175 |magazine=[[Aviation Week & Space Technology]] |title= AlliedSignal completes Lycoming acquisition |url=https://archive.aviationweek.com/issue/19941107/#!&pid=35 |url-access=subscription |surname=Kandebo |given=Stanley |publication-date=November 7, 1994 |page=35 |volume=141 |number=19}}</ref> <ref name="Interavia199410p16">{{cite magazine |issn=1423-3215 |magazine=[[Interavia (magazine)|Interavia]] |title=New power for regionals |given=Bill |surname=Sweetman |location=Minneapolis, Minnesota, U.S.A. |department=Finance, markets & industry |publication-date=October 1994 |pages=16–18 |volume=49 |number=583 |oclc=199793280 }}</ref> <ref name="CRAN19940718">{{cite newsletter |issn=1040-5402 |work=Commuter Regional Airline News |title=Textron Lycoming studies 9,000 lb-thrust LF509 for 'developed' RJ100 |publication-date=July 18, 1994 |page=2 |volume=12 |number=28 |id={{Gale|A15618034}}}}</ref> <ref name="FI19930825">{{cite magazine |issn=0015-3710 |url=https://www.flightglobal.com/pdfarchive/view/1993/1993%20-%202096.html |title=Engine for change |magazine=[[Flight International]] |date=25 August 1993 |given=Graham |surname=Warwick |pages=39+ |volume=144 |number=4384 |id={{Gale|A14335274}}}}</ref> <ref name="FI19920617">{{cite magazine |issn=0015-3710 |magazine=[[Flight International]] |title=Lycoming outlines LF500 power increase |given=Graham |surname=Warwick |publication-date=June 17, 1992 |page=8 |volume=141 |number=4323 |id={{Gale|A12271580}}}}</ref> <ref name="A-9A">{{cite book |pages=251–256 |section=A-X / A-9A close air support aircraft |section-url={{GBurl|-YEEDgAAQBAJ|p=251}} |title=Northrop: An aeronautical history |given=Fred |surname=Anderson |year=1976 |publisher=Wipf & Stock Publishers |isbn=9781532601460 |oclc=980678030}}</ref> <ref name="NASA19730004744">{{cite report |url=https://archive.org/details/NASA_NTRS_Archive_19730004744/page/n0 |title=Design study of an air pump and integral lift engine ALF-504 using the Lycoming 502 core |given=Dale |surname=Rauch |publisher=[[National Aeronautics and Space Administration]] (NASA) |number=NASA-CR-120992 |publication-date=July 1972 |hdl=2060/19730004744}} [https://ntrs.nasa.gov/search.jsp?R=19730004744 alternate url]</ref> }}
==Further reading== {{refbegin}} * {{cite news |issn=0015-3710 |work=[[Flight International]] |title=ALF502: Plugging the turbofan gap |url=https://ptacts.uspto.gov/ptacts/public-informations/petitions/1516455/download-documents?artifactId=169822875 |pages=237–241 |publication-date=January 30, 1982 |given=Richard |surname=Whitaker |others=Cutaway by Frank Munger |access-date=December 30, 2022 |archive-date=December 31, 2022 |archive-url=https://web.archive.org/web/20221231004242/https://ptacts.uspto.gov/ptacts/public-informations/petitions/1516455/download-documents?artifactId=169822875 |url-status=dead }} * {{cite AV media |work=Avco Lycoming Textron |type=brochure |title=The ALF 502R turbofan: Technology, ecology, economy |url=https://ptacts.uspto.gov/ptacts/public-informations/petitions/1485234/download-documents?artifactId=169514603 |archive-url=https://web.archive.org/web/20221231010815/https://ptacts.uspto.gov/ptacts/public-informations/petitions/1485234/download-documents?artifactId=169514603 |url-status=dead |archive-date=December 31, 2022 |access-date=December 30, 2022 }} {{refend}}
==External links== {{Commons category|Lycoming ALF 502}} * [https://web.archive.org/web/20080216183330/http://www.honeywell.com/sites/aero/Propulsion_Engines.htm Honeywell propulsion products page] * [https://web.archive.org/web/20080517224926/http://www.swiss-technical-services.com/tsindex/print/pr-honeywell-alf_502_507-technical-details Technical details from Swiss International Air Lines]
{{Lycoming aeroengines}} {{Garrett/Honeywell aeroengines}} {{USAF gas turbine engines}}
[[Category:Geared turbofan engines]] [[Category:High-bypass turbofan engines]] [[Category:Honeywell]] [[Category:Lycoming aircraft engines|ALF 502]] [[Category:Mixed-compressor gas turbines]] [[Category:1980s turbofan engines]]