Williams International FJ44-1AP
318 aircraft on the U.S. register carry a Williams International FJ44-1AP engine, rated at about 1,965 pounds of thrust. The Cessna 525 CitationJet (CJ series) is the model most often fitted with it (318 aircraft). The aircraft carrying it were built between 2006 and 2026.
The FAA records engines by code, usually at the level of a series ("O-320 series") rather than the exact variant; this page gathers every FAA code that reads as Williams International FJ44-1AP. FAA spelling: FJ44-1AP.
Where they are owner's state
Texas37California23Florida19Utah17Delaware16Tennessee15North Carolina13Montana12Missouri10Oklahoma9
Kind of aircraft
Business jets318 (100%)
When the aircraft were built by decade
What the FAA has certified, ordered and been told about the Williams International FJ44-1AP the component layer
No FAA order in the current files names this engine series. Operators and repair shops have filed 9 failure reports with the FAA since 1995, 9 of them in the last ten years.
Failure reports 9 since · what operators and shops told the FAA
Parts most often reported as the reports name them
Compressor4Fdu2Bushing1Fuel Control1Rotor1
Latest reports
2026-07-07Compressor: damaged
2025-01-21Compressor: damaged
2024-06-13Compressor: damaged
2024-03-04Bushing: missing
2021-03-03Fdu: failed
Sources: the FAA's type certificate data sheets, airworthiness directives, supplemental type certificates, special conditions and special airworthiness information bulletins (Dynamic Regulatory System), and the FAA's service difficulty reports. A failure report is what an operator or repair station chose to file; the counts show reporting as much as reliability, and larger and commercial fleets report more. How the systems are grouped.
Connections how this engine series links to the rest of the register
Fitted to
- Cessna 525 CitationJet (CJ series) 318 with this engine series
Where they are
- Texas 37 of these aircraft
- California 23 of these aircraft
- Florida 19 of these aircraft
- Utah 17 of these aircraft
- Delaware 16 of these aircraft
Biggest operators
- Bank Of Utah Trustee 5 of these aircraft
- Tvpx Aircraft Solutions INC Trustee 4 of these aircraft
- Joe Morten & Son INC 3 of these aircraft
Airworthiness
- Failure reports on the Williams International FJ44-1AP 9 reports since 1995
Analytics
These connections as data: /graph/engine/williams-international-fj44-1ap.json · about the eFlight graph.
Aircraft newest certificates first · 318
| Tail no. | Maker and model | Group | Owner and base | Certificate | Registered | Status |
|---|---|---|---|---|---|---|
| N525MS | Textron Aviation Inc 525 |
Fixed-wing, multi-engine | Building Specialties CO of Western Pennsylvania Saxonburg, Pennsylvania |
Standard | 2022-11-17 | ValidFAA registration status code V: Valid registration. All codes |
| N351BF | Textron Aviation Inc 525 |
Fixed-wing, multi-engine | Kbs Aviation LLC Springboro, Ohio |
Standard | 2022-11-09 | ValidFAA registration status code V: Valid registration. All codes |
| N934CW | Textron Aviation Inc 525 |
Fixed-wing, multi-engine | M2 Aviation LLC Rockledge, Florida |
Standard | 2022-11-01 | ValidFAA registration status code V: Valid registration. All codes |
| N333XA | Textron Aviation Inc 525 |
Fixed-wing, multi-engine | Jetnexa One LLC Gilbert, Arizona |
Standard | 2022-10-21 | ValidFAA registration status code V: Valid registration. All codes |
| N879SA | Textron Aviation Inc 525 |
Fixed-wing, multi-engine | Douma LLC Santa Teresa, New Mexico |
Standard | 2022-10-18 | ValidFAA registration status code V: Valid registration. All codes |
| N63YA | Cessna 525 |
Fixed-wing, multi-engine | Sarasbrij International INC Wilmington, Delaware |
Standard | 2022-10-13 | ValidFAA registration status code V: Valid registration. All codes |
| N858DP | Textron Aviation Inc 525 |
Fixed-wing, multi-engine | Dgt Aviation LLC New Bern, North Carolina |
Standard | 2022-09-30 | ValidFAA registration status code V: Valid registration. All codes |
| N1111S | Textron Aviation Inc 525 |
Fixed-wing, multi-engine | Stockbridge General Contracting INC Clovis, California |
Standard | 2022-09-27 | ValidFAA registration status code V: Valid registration. All codes |
| N646VP | Cessna 525 |
Fixed-wing, multi-engine | Co-owned owner Texas |
Standard | 2022-09-22 | ValidFAA registration status code V: Valid registration. All codes |
| N92SB | Textron Aviation Inc 525 |
Fixed-wing, multi-engine | Lone Star Air LLC Castle Rock, Colorado |
Standard | 2022-09-08 | ValidFAA registration status code V: Valid registration. All codes |
| N907GW | Textron Aviation Inc 525 |
Fixed-wing, multi-engine | Pnc Bank Na Boise, Idaho |
Standard | 2022-07-27 | ValidFAA registration status code V: Valid registration. All codes |
| N731DC | Textron Aviation Inc 525 |
Fixed-wing, multi-engine | Sunshine Aviation LLC Jackson, Tennessee |
Standard | 2022-07-09 | ValidFAA registration status code V: Valid registration. All codes |
| N717BR | Textron Aviation Inc 525 |
Fixed-wing, multi-engine | Semper Fi Aviation LLC Aledo, Texas |
Standard | 2022-07-05 | ValidFAA registration status code V: Valid registration. All codes |
| N906RR | Textron Aviation Inc 525 |
Fixed-wing, multi-engine | Hill Country Restaurants INC Nacogdoches, Texas |
Standard | 2022-06-25 | ValidFAA registration status code V: Valid registration. All codes |
| N885JH | Textron Aviation Inc 525 |
Fixed-wing, multi-engine | O & H Air LLC Paris, Texas |
Standard | 2022-06-22 | ValidFAA registration status code V: Valid registration. All codes |
| N882MZ | Textron Aviation Inc 525 |
Fixed-wing, multi-engine | 7-Star Aviation LLC Addison, Texas |
Standard | 2022-05-28 | ValidFAA registration status code V: Valid registration. All codes |
| N901GG | Textron Aviation Inc 525 |
Fixed-wing, multi-engine | Long Bay Partners LLC Missoula, Montana |
Standard | 2022-05-26 | ValidFAA registration status code V: Valid registration. All codes |
| N889TA | Cessna 525 |
Fixed-wing, multi-engine | Private Flight II LLC Oklahoma City, Oklahoma |
Standard | 2022-05-25 | ValidFAA registration status code V: Valid registration. All codes |
| N514CK | Textron Aviation Inc 525 |
Fixed-wing, multi-engine | Kenvic Aviation LLC De Armanville, Alabama |
Standard | 2022-05-11 | ValidFAA registration status code V: Valid registration. All codes |
| N699CJ | Cessna 525 |
Fixed-wing, multi-engine | Sra/Rombert Aviation LLC Miami Beach, Florida |
Special flight permit | 2022-05-04 | ValidFAA registration status code V: Valid registration. All codes |
| N68KK | Textron Aviation Inc 525 |
Fixed-wing, multi-engine | C&J Aviationllc Wichita, Kansas |
Standard | 2022-03-23 | ValidFAA registration status code V: Valid registration. All codes |
| N788JW | Textron Aviation Inc 525 |
Fixed-wing, multi-engine | North Fork Place LLC Bozeman, Montana |
Standard | 2022-03-07 | ValidFAA registration status code V: Valid registration. All codes |
| N571GT | Textron Aviation Inc 525 |
Fixed-wing, multi-engine | Conrad Aviation LLC Forest Hill, Louisiana |
Standard | 2022-03-03 | ValidFAA registration status code V: Valid registration. All codes |
| N580Z | Cessna 525 |
Fixed-wing, multi-engine | Taft Enterprises LLC Wilmington, Delaware |
Standard | 2022-01-31 | ValidFAA registration status code V: Valid registration. All codes |
| N84BA | Cessna 525 |
Fixed-wing, multi-engine | A & W Aviation LLC Lafayette, Louisiana |
Standard | 2022-01-19 | ValidFAA registration status code V: Valid registration. All codes |
| N70GM | Cessna 525 |
Fixed-wing, multi-engine | Seh Aviation LLC Boaz, Alabama |
Standard | 2022-01-10 | ValidFAA registration status code V: Valid registration. All codes |
| N2ZB | Textron Aviation Inc 525 |
Fixed-wing, multi-engine | Citizen Aero INC Trustee Sheridan, Wyoming |
Standard | 2021-12-16 | ValidFAA registration status code V: Valid registration. All codes |
| N85WH | Textron Aviation Inc 525 |
Fixed-wing, multi-engine | M Hixson Aviation LLC Lake Dallas, Texas |
Standard | 2021-12-11 | ValidFAA registration status code V: Valid registration. All codes |
| N933RG | Textron Aviation Inc 525 |
Fixed-wing, multi-engine | Co-owned owner Florida |
Standard | 2021-12-08 | ValidFAA registration status code V: Valid registration. All codes |
| N251GM | Textron Aviation Inc 525 |
Fixed-wing, multi-engine | Jrjgc Investments LLC Saltillo, Mississippi |
Standard | 2021-10-30 | ValidFAA registration status code V: Valid registration. All codes |
| N918LP | Textron Aviation Inc 525 |
Fixed-wing, multi-engine | New Chat Air LLC Chattanooga, Tennessee |
Standard | 2021-10-15 | ValidFAA registration status code V: Valid registration. All codes |
| N896TW | Textron Aviation Inc 525 |
Fixed-wing, multi-engine | Shineair LLC Collierville, Tennessee |
Standard | 2021-09-28 | ValidFAA registration status code V: Valid registration. All codes |
| N716DJ | Textron Aviation Inc 525 |
Fixed-wing, multi-engine | N716Dj LLC Kentwood, Michigan |
Standard | 2021-09-20 | ValidFAA registration status code V: Valid registration. All codes |
| N333SL | Textron Aviation Inc 525 |
Fixed-wing, multi-engine | T C Air LLC West Linn, Oregon |
Standard | 2021-09-01 | ValidFAA registration status code V: Valid registration. All codes |
| N408RK | Cessna 525 |
Fixed-wing, multi-engine | Polar Palms LLC Helena, Montana |
Standard | 2021-07-08 | ValidFAA registration status code V: Valid registration. All codes |
| N529TA | Textron Aviation Inc 525 |
Fixed-wing, multi-engine | Todhunter Aviation LLC Wilmington, Delaware |
Standard | 2021-05-10 | ValidFAA registration status code V: Valid registration. All codes |
| N525TG | Cessna 525 |
Fixed-wing, multi-engine | Royal Air LLC Glenwood Springs, Colorado |
Standard | 2021-04-24 | ValidFAA registration status code V: Valid registration. All codes |
| N363BS | Textron Aviation Inc 525 |
Fixed-wing, multi-engine | Mjti LLC Santa Rosa, California |
Standard | 2021-04-10 | ValidFAA registration status code V: Valid registration. All codes |
| N723NC | Textron Aviation Inc 525 |
Fixed-wing, multi-engine | C&N Aviation LLC Tucson, Arizona |
Standard | 2021-03-24 | ValidFAA registration status code V: Valid registration. All codes |
| N821CD | Textron Aviation Inc 525 |
Fixed-wing, multi-engine | J & B Quick Air LLC Overland Park, Kansas |
Standard | 2021-02-13 | ValidFAA registration status code V: Valid registration. All codes |
| N610CL | Textron Aviation Inc 525 |
Fixed-wing, multi-engine | Tvpx Aircraft Solutions INC Trustee North Salt Lake, Utah |
Standard | 2021-02-04 | ValidFAA registration status code V: Valid registration. All codes |
| N607TN | Cessna 525 |
Fixed-wing, multi-engine | Winging It LLC Little Rock, Arkansas |
Standard | 2021-01-25 | ValidFAA registration status code V: Valid registration. All codes |
| N427KP | Cessna 525 |
Fixed-wing, multi-engine | Kp Equipment LLC Annandale, Minnesota |
Standard | 2020-12-22 | ValidFAA registration status code V: Valid registration. All codes |
| N92WG | Cessna 525 |
Fixed-wing, multi-engine | Dndd Capital Holdings LLC Plano, Texas |
Standard | 2020-11-17 | ValidFAA registration status code V: Valid registration. All codes |
| N545LS | Cessna 525 |
Fixed-wing, multi-engine | Blue Earth Cellular LLC Blue Earth, Minnesota |
Standard | 2020-11-10 | ValidFAA registration status code V: Valid registration. All codes |
| N1865C | Cessna 525 |
Fixed-wing, multi-engine | Hotel Alpha LLC Tampa, Florida |
Standard | 2020-11-02 | ValidFAA registration status code V: Valid registration. All codes |
| N845LB | Textron Aviation Inc 525 |
Fixed-wing, multi-engine | Bank of Utah Trustee Salt Lake City, Utah |
Standard | 2020-10-02 | ValidFAA registration status code V: Valid registration. All codes |
| N3JS | Textron Aviation Inc 525 |
Fixed-wing, multi-engine | Oriole Capital LLC Wilmington, Delaware |
Standard | 2020-09-30 | ValidFAA registration status code V: Valid registration. All codes |
| N304BP | Textron Aviation Inc 525 |
Fixed-wing, multi-engine | Intermountain Air INC Colorado Springs, Colorado |
Standard | 2020-08-25 | ValidFAA registration status code V: Valid registration. All codes |
| N525JD | Cessna 525 |
Fixed-wing, multi-engine | Cuprum Aviation LLC Wellington, Florida |
Standard | 2020-05-28 | ValidFAA registration status code V: Valid registration. All codes |
| N557HP | Cessna 525 |
Fixed-wing, multi-engine | Blues City Aviation LLC Germantown, Tennessee |
Standard | 2020-05-11 | ValidFAA registration status code V: Valid registration. All codes |
| N570CJ | Textron Aviation Inc 525 |
Fixed-wing, multi-engine | Je Consulting LLC Geneseo, Illinois |
Standard | 2020-04-29 | ValidFAA registration status code V: Valid registration. All codes |
| N876MS | Cessna 525 |
Fixed-wing, multi-engine | Avoboe LLC North Little Rock, Arkansas |
Standard | 2020-04-17 | ValidFAA registration status code V: Valid registration. All codes |
| N104LW | Cessna 525 |
Fixed-wing, multi-engine | St Croix Acceptance CORP Devils Lake, North Dakota |
Standard | 2020-04-07 | ValidFAA registration status code V: Valid registration. All codes |
| N998CM | Textron Aviation Inc 525 |
Fixed-wing, multi-engine | Tango Kilo Enterprises INC Surfside, California |
Standard | 2020-03-31 | ValidFAA registration status code V: Valid registration. All codes |
| N71SY | Cessna 525 |
Fixed-wing, multi-engine | Silver Wing At Sandpoint LLC Torrance, California |
Standard | 2020-02-19 | ValidFAA registration status code V: Valid registration. All codes |
| N318JH | Cessna 525 |
Fixed-wing, multi-engine | Air Hoffmann LLC Saint Louis, Missouri |
Standard | 2020-01-13 | ValidFAA registration status code V: Valid registration. All codes |
| N75VK | Textron Aviation Inc 525 |
Fixed-wing, multi-engine | Maranatha Leasing & Consulting INC Marco Island, Florida |
Standard | 2019-12-10 | ValidFAA registration status code V: Valid registration. All codes |
| N971MB | Textron Aviation Inc 525 |
Fixed-wing, multi-engine | Adjacent Air LLC Holdrege, Nebraska |
Standard | 2019-12-02 | ValidFAA registration status code V: Valid registration. All codes |
| N85SC | Textron Aviation Inc 525 |
Fixed-wing, multi-engine | Struthoff CO INC San Antonio, Texas |
Standard | 2019-11-22 | ValidFAA registration status code V: Valid registration. All codes |
| N525HL | Cessna 525 |
Fixed-wing, multi-engine | Bank of Utah Trustee Salt Lake City, Utah |
Standard | 2019-11-07 | ValidFAA registration status code V: Valid registration. All codes |
| N18466 | Textron Aviation Inc 525 |
Fixed-wing, multi-engine | Pantaxios LLC Spencerport, New York |
Standard | 2019-10-24 | ValidFAA registration status code V: Valid registration. All codes |
| N26DT | Cessna 525 |
Fixed-wing, multi-engine | Mdr Construction INC Columbia, Mississippi |
Standard | 2019-07-15 | ValidFAA registration status code V: Valid registration. All codes |
| N508WG | Textron Aviation Inc 525 |
Fixed-wing, multi-engine | Jobs Lane Aviation LLC Englewood Cliffs, New Jersey |
Standard | 2019-06-27 | ValidFAA registration status code V: Valid registration. All codes |
| N107JG | Textron Aviation Inc 525 |
Fixed-wing, multi-engine | Grundy Aviation LLC Horsham, Pennsylvania |
Standard | 2019-04-26 | ValidFAA registration status code V: Valid registration. All codes |
| N394GA | Cessna 525 |
Fixed-wing, multi-engine | Aircraft Owners and Pilots Association Frederick, Maryland |
Standard | 2019-03-09 | ValidFAA registration status code V: Valid registration. All codes |
| N484AG | Cessna 525 |
Fixed-wing, multi-engine | Buckhorn Draw LLC San Angelo, Texas |
Standard | 2019-02-11 | ValidFAA registration status code V: Valid registration. All codes |
| N837PF | Textron Aviation Inc 525 |
Fixed-wing, multi-engine | Southeastern Red Holdings LLC Wellington, Florida |
Standard | 2019-02-09 | ValidFAA registration status code V: Valid registration. All codes |
| N727SB | Textron Aviation Inc 525 |
Fixed-wing, multi-engine | Eta Partners LLC Bossier City, Louisiana |
Standard | 2019-02-06 | ValidFAA registration status code V: Valid registration. All codes |
| N65CK | Cessna 525A |
Fixed-wing, multi-engine | Curo Group LLC Chesterfield, Missouri |
Standard | 2019-02-05 | ValidFAA registration status code V: Valid registration. All codes |
| N186DL | Cessna 525 |
Fixed-wing, multi-engine | Aesop LLC Las Vegas, Nevada |
Standard | 2018-12-27 | ValidFAA registration status code V: Valid registration. All codes |
| N626RM | Textron Aviation Inc 525 |
Fixed-wing, multi-engine | Tvpx Ars INC Trustee North Salt Lake, Utah |
Standard | 2018-12-20 | ValidFAA registration status code V: Valid registration. All codes |
| N797BK | Textron Aviation Inc 525 |
Fixed-wing, multi-engine | Blue Bird of Happiness LLC Shreveport, Louisiana |
Standard | 2018-11-20 | ValidFAA registration status code V: Valid registration. All codes |
| N527PT | Textron Aviation Inc 525 |
Fixed-wing, multi-engine | Satelite Industries INC Minneapolis, Minnesota |
Standard | 2018-11-17 | ValidFAA registration status code V: Valid registration. All codes |
| N212RH | Cessna 525 |
Fixed-wing, multi-engine | Csc Delaware Trust CO Trustee Wilmington, Delaware |
Standard | 2018-09-04 | ValidFAA registration status code V: Valid registration. All codes |
| N464BH | Cessna 525 |
Fixed-wing, multi-engine | Pajarito Investments LLC Salt Lake City, Utah |
Standard | 2018-08-29 | ValidFAA registration status code V: Valid registration. All codes |
| N881RC | Cessna 525 |
Fixed-wing, multi-engine | Cooper Companies INC Scottsdale, Arizona |
Standard | 2018-08-27 | ValidFAA registration status code V: Valid registration. All codes |
| N81CP | Cessna 525 |
Fixed-wing, multi-engine | 78Cl Aviation LLC Ogden, Utah |
Standard | 2018-08-18 | ValidFAA registration status code V: Valid registration. All codes |
| N522WP | Textron Aviation Inc 525 |
Fixed-wing, multi-engine | M & M Aviation LLC Lincoln, Nebraska |
Standard | 2018-07-03 | ValidFAA registration status code V: Valid registration. All codes |
| N967TG | Cessna 525A |
Fixed-wing, multi-engine | Tc Flight LLC San Francisco, California |
Standard | 2018-05-10 | ValidFAA registration status code V: Valid registration. All codes |
| N890MT | Textron Aviation Inc 525 |
Fixed-wing, multi-engine | Individual owner Oregon |
Standard | 2018-02-28 | ValidFAA registration status code V: Valid registration. All codes |
| N324BD | Cessna 525 |
Fixed-wing, multi-engine | Godwin Aviation LLC Dunn, North Carolina |
Standard | 2018-02-20 | ValidFAA registration status code V: Valid registration. All codes |
| N465JK | Textron Aviation Inc 525 |
Fixed-wing, multi-engine | Dodeca Resources INC Henderson, Nevada |
Standard | 2018-01-23 | ValidFAA registration status code V: Valid registration. All codes |
| N813FM | Textron Aviation Inc 525 |
Fixed-wing, multi-engine | Kevin Parra Aviation LLC San Diego, California |
Standard | 2018-01-05 | ValidFAA registration status code V: Valid registration. All codes |
| N711JB | Textron Aviation Inc 525 |
Fixed-wing, multi-engine | Cj-M 03207 LLC Elizabethton, Tennessee |
Standard | 2017-12-18 | ValidFAA registration status code V: Valid registration. All codes |
| N525WX | Textron Aviation Inc 525 |
Fixed-wing, multi-engine | Xsurgo Aviation INC Nashville, Tennessee |
Standard | 2017-10-31 | ValidFAA registration status code V: Valid registration. All codes |
| N966BB | Textron Aviation Inc 525 |
Fixed-wing, multi-engine | Tvpx Aircraft Solutions INC Trustee North Salt Lake, Utah |
Standard | 2017-10-31 | ValidFAA registration status code V: Valid registration. All codes |
| N732M | Cessna Aircraft Co 525 |
Fixed-wing, multi-engine | Textron Aviation INC Wichita, Kansas |
Experimental | 2017-07-25 | ValidFAA registration status code V: Valid registration. All codes |
| N829BC | Textron Aviation Inc 525 |
Fixed-wing, multi-engine | Berry Companies INC Wichita, Kansas |
Standard | 2017-06-01 | ValidFAA registration status code V: Valid registration. All codes |
| N287CB | Textron Aviation Inc 525 |
Fixed-wing, multi-engine | Cottingham & Butler Insurance Services INC Dubuque, Iowa |
Standard | 2017-04-17 | ValidFAA registration status code V: Valid registration. All codes |
| N525GE | Cessna 525 |
Fixed-wing, multi-engine | Kek Companies INC Portland, Oregon |
Standard | 2017-04-11 | ValidFAA registration status code V: Valid registration. All codes |
| N460RM | Textron Aviation Inc 525 |
Fixed-wing, multi-engine | Mustang Two LLC Newport Beach, California |
Standard | 2016-09-28 | ValidFAA registration status code V: Valid registration. All codes |
| N28FD | Cessna 525 |
Fixed-wing, multi-engine | Pacific Air Center LLC Long Beach, California |
Standard | 2016-08-09 | ValidFAA registration status code V: Valid registration. All codes |
| N575TM | Cessna 525 |
Fixed-wing, multi-engine | Co-owned owner Texas |
Standard | 2016-05-13 | ValidFAA registration status code V: Valid registration. All codes |
| N487CB | Textron Aviation Inc 525 |
Fixed-wing, multi-engine | Cottingham & Butler Insurance Services INC Dubuque, Iowa |
Standard | 2016-05-04 | ValidFAA registration status code V: Valid registration. All codes |
| N921XT | Textron Aviation Inc 525 |
Fixed-wing, multi-engine | Sundance Mc LLC Dallas, Texas |
Standard | 2016-04-12 | ValidFAA registration status code V: Valid registration. All codes |
| N525KH | Textron Aviation Inc 525 |
Fixed-wing, multi-engine | Kh Aviation Tbm 850 LLC Prospect Heights, Illinois |
Standard | 2016-04-04 | ValidFAA registration status code V: Valid registration. All codes |
| N106MJ | Textron Aviation Inc 525 |
Fixed-wing, multi-engine | Angstrom Aviation LLC Southfield, Michigan |
Standard | 2016-02-11 | ValidFAA registration status code V: Valid registration. All codes |
| N52ZG | Textron Aviation Inc 525 |
Fixed-wing, multi-engine | Lift Aviation LLC Aspen, Colorado |
Standard | 2016-01-05 | ValidFAA registration status code V: Valid registration. All codes |
| N986PR | Textron Aviation Inc 525 |
Fixed-wing, multi-engine | Edwards Air LLC Paducah, Kentucky |
Standard | 2015-12-23 | ValidFAA registration status code V: Valid registration. All codes |
Source: FAA Civil Aviation Registry, Releasable Aircraft Database (the engine reference table and each aircraft's engine code), October 5, 2026. Horsepower and thrust are the FAA's figures for the series, not for a particular aircraft.