Lycoming O-540 series
5,244 aircraft on the U.S. register carry a Lycoming O-540 series engine, rated at about 250 horsepower. The Piper PA-28 Cherokee, Warrior, Archer and Arrow is the model most often fitted with it (1,226 aircraft). The aircraft carrying it were built between 1958 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 Lycoming O-540 series (2 codes). FAA spellings: 0-540 SERIES · O-540 SERIES.
Fitted to model families
Piper PA-28 Cherokee, Warrior, Archer and Arrow1,226Piper PA-24 Comanche1,162Piper PA-32 Cherokee Six, Lance and Saratoga641Cessna R182 Skylane RG613Cessna TR182 Turbo Skylane RG413Piper PA-25 Pawnee333Maule M-5148Robinson R44138Piper PA-23 Apache and Aztec138Maule M-759Cessna T182 Turbo Skylane53Britten-Norman BN-229
Model families, as a table
Piper PA-28 Cherokee, Warrior, Archer and Arrow · Piper PA-24 Comanche · Piper PA-32 Cherokee Six, Lance and Saratoga · Cessna R182 Skylane RG · Cessna TR182 Turbo Skylane RG · Piper PA-25 Pawnee · Maule M-5 · Robinson R44 · Piper PA-23 Apache and Aztec · Maule M-7
Where they are owner's state
Kind of aircraft
By kind, as a table
| aircraft | share | |
|---|---|---|
| Piston singles | 4,903 | 93% |
| Piston twins | 198 | 4% |
| Helicopters | 140 | 3% |
| Turboprops | 3 | 0.1% |
What the FAA has certified, ordered and been told about the Lycoming O-540 series the component layer
The design is held under 1 type certificate (E-295, held by Lycoming Engines). The FAA has issued 28 airworthiness directives (orders that owners must comply with) that name this engine series. Operators and repair shops have filed 304 failure reports with the FAA since 1995, 20 of them in the last ten years.
FAA orders 28 airworthiness directives · newest first
2026-09-142026-17-10 · Reciprocating Engine Cylinder Section · engine
2026-04-082026-04-11 · Engine (Reciprocating) · engine
2024-12-052024-21-02 · Engine (Reciprocating) · engine
2022-08-152022-16-03 · Engine (RECIPROCATING) · engine
2017-08-152017-16-11 · Reciprocating Engine Power Section · engine
2012-10-242012-19-01 · Crankshafts · engine
Failure reports 304 since · what operators and shops told the FAA
Failure reports by year, as a table
| reports | |
|---|---|
| 95 | 14 |
| 96 | 26 |
| 97 | 5 |
| 98 | 11 |
| 99 | 2 |
| 00 | 15 |
| 01 | 20 |
| 02 | 61 |
| 03 | 18 |
| 04 | 25 |
| 05 | 13 |
| 06 | 18 |
| 07 | 12 |
| 08 | 3 |
| 09 | 4 |
| 10 | 11 |
| 11 | 4 |
| 12 | 5 |
| 13 | 6 |
| 14 | 3 |
| 15 | 7 |
| 16 | 1 |
| 17 | 1 |
| 18 | 3 |
| 19 | 4 |
| 20 | 3 |
| 21 | 1 |
| 22 | 3 |
| 23 | 1 |
| 24 | 2 |
| 25 | 1 |
| 26 | 1 |
Parts most often reported as the reports name them
Magneto11Light10Carburetor8Line8Clamp7Pin7Valve7Boot6Bulkhead6Hose6
Parts most reported, as a table
| reports | |
|---|---|
| Magneto | 11 |
| Light | 10 |
| Carburetor | 8 |
| Line | 8 |
| Clamp | 7 |
| Pin | 7 |
| Valve | 7 |
| Boot | 6 |
| Bulkhead | 6 |
| Hose | 6 |
Latest reports
2026-05-09Thrust Button: faulty
2025-06-06Housing: failed
2024-09-25Magneto: making metal
2024-04-02Rod: scored
2023-06-27Solenoid: defective
Certificates and bulletins
E-295Type certificate held by Lycoming Engines · 47 models listed · revised April 30, 2013
Safety bulletins 10 · advice, not orders
2019-05-02NE-19-08 · Reciprocating Engine Cylinder Section - Lycoming Engines Parallel Valve Cylinders
2016-05-13NE-08-32R1 · Propeller Governor Idler Gear Shaft Set Screw
2014-03-24NE-14-13 · Reciprocating Engine - Cylinder Mounting Studs
2012-11-21NE-13-06 · Pushrod Shroud Spring Retainers, Engine Components Part No. AEL14995, for Lycoming Engines 320,...
2011-03-31NE-08-26R3 · Magneto/Distributor
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
- Piper PA-28 Cherokee, Warrior, Archer and Arrow 1,226 with this engine series
- Piper PA-24 Comanche 1,162 with this engine series
- Piper PA-32 Cherokee Six, Lance and Saratoga 641 with this engine series
- Cessna R182 Skylane RG 613 with this engine series
- Cessna TR182 Turbo Skylane RG 413 with this engine series
- Piper PA-25 Pawnee 333 with this engine series
- Maule M-5 148 with this engine series
- Robinson R44 138 with this engine series
Where they are
- California 549 of these aircraft
- Texas 467 of these aircraft
- Florida 358 of these aircraft
- Arizona 198 of these aircraft
- Colorado 182 of these aircraft
Biggest operators
- Bas Part Sales LLC 21 of these aircraft
- International Air Services INC Trustee 13 of these aircraft
- Aerial Banners INC 13 of these aircraft
- Quality Aviation INC 9 of these aircraft
- Ttwn Media Networks LLC 7 of these aircraft
Airworthiness
- FAA orders naming the Lycoming O-540 series 28 airworthiness directives
- Failure reports on the Lycoming O-540 series 304 reports since 1995
Analytics
The whole map of how records connect · these connections as data: /graph/engine/lycoming-o-540-series.json.
Aircraft newest certificates first · 5,244
| Tail no. | Maker and model | Group | Owner and base | Certificate | Registered | Status |
|---|---|---|---|---|---|---|
| N182RN | Cessna R182 |
Fixed-wing, single engine | Individual owner Ohio |
Standard | 1978-06-13 | ValidFAA registration status code V: Valid registration. All codes |
| N7494P | Piper PA-24-250 |
Fixed-wing, single engine | M and P Aviation INC Albia, Iowa |
Standard | 1978-04-11 | ValidFAA registration status code V: Valid registration. All codes |
| N7161P | Piper PA-24-250 |
Fixed-wing, single engine | Individual owner Montana |
Standard | 1978-01-31 | ValidFAA registration status code V: Valid registration. All codes |
| N9147W | Piper PA-28-235 |
Fixed-wing, single engine | Individual owner California |
Standard | 1978-01-23 | ValidFAA registration status code V: Valid registration. All codes |
| N4614P | Piper PA-23-250 |
Fixed-wing, multi-engine | Individual owner California |
Restricted | 1977-11-29 | ValidFAA registration status code V: Valid registration. All codes |
| N5366P | Piper PA-24-250 |
Fixed-wing, single engine | Co-owned owner California |
Standard | 1977-09-22 | ValidFAA registration status code V: Valid registration. All codes |
| N6150P | Piper PA-24-250 |
Fixed-wing, single engine | Individual owner Georgia |
Standard | 1977-07-11 | ValidFAA registration status code V: Valid registration. All codes |
| N4629Y | Piper PA-25-235 |
Fixed-wing, single engine | Barts Flying Service INC Storm Lake, Iowa |
Restricted | 1977-03-01 | ValidFAA registration status code V: Valid registration. All codes |
| N3561W | Piper PA-32-260 |
Fixed-wing, single engine | Individual owner Wisconsin |
Standard | 1976-06-21 | ValidFAA registration status code V: Valid registration. All codes |
| N6540P | Piper PA-24-250 |
Fixed-wing, single engine | Individual owner Missouri |
Standard | 1976-04-22 | ValidFAA registration status code V: Valid registration. All codes |
| N8552L | Piper PA-25-235 |
Fixed-wing, single engine | Individual owner South Carolina |
Restricted | 1976-04-21 | ValidFAA registration status code V: Valid registration. All codes |
| N8937W | Piper PA-28-235 |
Fixed-wing, single engine | Individual owner New Mexico |
Standard | 1975-02-05 | ValidFAA registration status code V: Valid registration. All codes |
| N7704P | Piper PA-24-250 |
Fixed-wing, single engine | Individual owner Kansas |
Standard | 1974-11-11 | ValidFAA registration status code V: Valid registration. All codes |
| N43664 | Piper PA-32-260 |
Fixed-wing, single engine | Individual owner North Carolina |
Standard | 1974-08-29 | ValidFAA registration status code V: Valid registration. All codes |
| N4832Y | Piper PA-25-260 |
Fixed-wing, single engine | Individual owner Iowa |
Restricted | 1974-05-24 | ValidFAA registration status code V: Valid registration. All codes |
| N7248V | Intermountain CALLAIR A-9 |
Fixed-wing, single engine | Individual owner Colorado |
Restricted | 1974-03-07 | ValidFAA registration status code V: Valid registration. All codes |
| N6170P | Piper PA-24-250 |
Fixed-wing, single engine | Individual owner Montana |
Standard | 1973-05-07 | ValidFAA registration status code V: Valid registration. All codes |
| N7092P | Piper PA-24-250 |
Fixed-wing, single engine | Individual owner Texas |
Standard | 1973-01-16 | ValidFAA registration status code V: Valid registration. All codes |
| N6163P | Piper PA-24-250 |
Fixed-wing, single engine | Commache Avn INC Flint, Michigan |
Standard | 1972-01-31 | ValidFAA registration status code V: Valid registration. All codes |
| N702SP | Piper PA-23-250 |
Fixed-wing, multi-engine | Sportsmans Market INC Batavia, Ohio |
Standard | 1972-01-07 | ValidFAA registration status code V: Valid registration. All codes |
| N8082P | Piper PA-24-250 |
Fixed-wing, single engine | Skyriders INC Albuquerque, New Mexico |
Standard | 1971-08-11 | ValidFAA registration status code V: Valid registration. All codes |
| N7818P | Piper PA-24-250 |
Fixed-wing, single engine | Individual owner Michigan |
Standard | 1970-10-05 | ValidFAA registration status code V: Valid registration. All codes |
| N260C | Piper PA-28-235 |
Fixed-wing, single engine | Individual owner North Carolina |
Standard | 1970-09-14 | ValidFAA registration status code V: Valid registration. All codes |
| N3986W | Piper PA-32-260 |
Fixed-wing, single engine | Delaware Flyers INC Fort Wayne, Indiana |
Standard | 1970-05-26 | ValidFAA registration status code V: Valid registration. All codes |
| N747VT | Piper PA-28-235 |
Fixed-wing, single engine | Individual owner Montana |
Standard | 1969-02-06 | ValidFAA registration status code V: Valid registration. All codes |
| N8769W | Piper PA-28-235 |
Fixed-wing, single engine | Dublin Aviation CORP Columbus, Ohio |
Standard | 1967-10-23 | RevokedFAA registration status code 22: Revoked, canceled. All codes |
| N3738W | Piper PA-32-260 |
Fixed-wing, single engine | Newton Machine CO INC Charlotte, North Carolina |
Standard | 1967-06-20 | ValidFAA registration status code V: Valid registration. All codes |
| N111SL | Piper PA-24-250 |
Fixed-wing, single engine | Individual owner Colorado |
Standard | ValidFAA registration status code V: Valid registration. All codes | |
| N1246T | Piper PA-32-260 |
Fixed-wing, single engine | Individual owner Florida |
Standard | PendingFAA registration status code R: Registration pending. All codes | |
| N12RD | Piper PA-24-250 |
Fixed-wing, single engine | Flying Colors Airparts INC Leesburg, Florida |
Standard | ValidFAA registration status code V: Valid registration. All codes | |
| N150B | Robinson Helicopter R44 |
Helicopter | Withheld at owner's request | Standard | PendingFAA registration status code R: Registration pending. All codes | |
| N15126 | Piper PA-32-260 |
Fixed-wing, single engine | Individual owner Georgia |
Standard | PendingFAA registration status code R: Registration pending. All codes | |
| N16556 | Piper PA-28-235 |
Fixed-wing, single engine | Individual owner North Dakota |
Standard | Sale reportedFAA registration status code 17: Sale reported, pending cancellation. All codes | |
| N1716R | Cessna R182 |
Fixed-wing, single engine | Individual owner Texas |
Standard | PendingFAA registration status code R: Registration pending. All codes | |
| N171WC | Robinson Helicopter R44 ASTRO |
Helicopter | Individual owner Illinois |
Standard | PendingFAA registration status code R: Registration pending. All codes | |
| N18010 | Dehavilland DHC-1B-2 |
Fixed-wing, single engine | Individual owner | Experimental | Sale reportedFAA registration status code 7. All codes | |
| N182GZ | Cessna R182 |
Fixed-wing, single engine | Aircraft By Farkas LLC Middleburg Heights, Ohio |
Standard | ValidFAA registration status code V: Valid registration. All codes | |
| N182KC | Cessna TR182 |
Fixed-wing, single engine | Bas Part Sales LLC Greeley, Colorado |
Standard | ValidFAA registration status code V: Valid registration. All codes | |
| N1981H | Piper PA-32-260 |
Fixed-wing, single engine | Individual owner Missouri |
Standard | PendingFAA registration status code R: Registration pending. All codes | |
| N200MA | Piper PA-32RT-300T |
Fixed-wing, single engine | Bas Part Sales LLC Greeley, Colorado |
Standard | ValidFAA registration status code V: Valid registration. All codes | |
| N2024S | Cessna R182 |
Fixed-wing, single engine | Individual owner Kansas |
Standard | PendingFAA registration status code R: Registration pending. All codes | |
| N20522 | Cessna R182 |
Fixed-wing, single engine | Individual owner | Standard | CanceledFAA registration status code 18: Sale reported, canceled. All codes | |
| N235CR | Piper PA-28-235 |
Fixed-wing, single engine | Individual owner Texas |
Standard | PendingFAA registration status code R: Registration pending. All codes | |
| N236AG | Cessna R182 |
Fixed-wing, single engine | Troposphere Ventures LLC Fond du Lac, Wisconsin |
Standard | ValidFAA registration status code V: Valid registration. All codes | |
| N241DK | Douglas Ripley BEARHAWK |
Fixed-wing, single engine | Individual owner Delaware |
Experimental | Sale reportedFAA registration status code 7. All codes | |
| N260CS | Piper PA-32-260 |
Fixed-wing, single engine | Individual owner Alaska |
Standard | PendingFAA registration status code R: Registration pending. All codes | |
| N27PC | Piper PA-24-250 |
Fixed-wing, single engine | Individual owner Texas |
Standard | PendingFAA registration status code R: Registration pending. All codes | |
| N3224W | Piper PA-32-260 |
Fixed-wing, single engine | Medic Choppers LLC Springdale, Arkansas |
Standard | ValidFAA registration status code V: Valid registration. All codes | |
| N32785 | Piper PA-32-260 |
Fixed-wing, single engine | Individual owner Alaska |
Standard | PendingFAA registration status code R: Registration pending. All codes | |
| N3368W | Piper PA-32-260 |
Fixed-wing, single engine | Individual owner Texas |
Standard | PendingFAA registration status code R: Registration pending. All codes | |
| N3457W | Piper PA-32-260 |
Fixed-wing, single engine | Bas Part Sales LLC Greeley, Colorado |
Standard | ValidFAA registration status code V: Valid registration. All codes | |
| N3460W | Piper PA-32-260 |
Fixed-wing, single engine | Individual owner Minnesota |
Standard | Sale reportedFAA registration status code 17: Sale reported, pending cancellation. All codes | |
| N3483W | Piper PA-32-260 |
Fixed-wing, single engine | Individual owner Texas |
Standard | Sale reportedFAA registration status code 7. All codes | |
| N3571G | Callair A-9 |
Fixed-wing, single engine | Mid Continent Aircraft CORP Hayti, Missouri |
Restricted | ValidFAA registration status code V: Valid registration. All codes | |
| N3571P | Piper PA-28-236 |
Fixed-wing, single engine | Individual owner South Carolina |
Standard | PendingFAA registration status code R: Registration pending. All codes | |
| N3784W | Piper PA-32-260 |
Fixed-wing, single engine | Bas Part Sales LLC Greeley, Colorado |
Standard | ValidFAA registration status code V: Valid registration. All codes | |
| N3793W | Piper PA-32-260 |
Fixed-wing, single engine | Bas Part Sales LLC Greeley, Colorado |
Standard | ValidFAA registration status code V: Valid registration. All codes | |
| N3801W | Piper PA-32-260 |
Fixed-wing, single engine | Individual owner Iowa |
Standard | Sale reportedFAA registration status code 7. All codes | |
| N3879W | Piper PA-32-260 |
Fixed-wing, single engine | Individual owner Texas |
Standard | Sale reportedFAA registration status code 7. All codes | |
| N395X | Maule M-5-235C |
Fixed-wing, single engine | Individual owner Montana |
Standard | PendingFAA registration status code R: Registration pending. All codes | |
| N4166C | Cessna R182 |
Fixed-wing, single engine | Bas Part Sales LLC Greeley, Colorado |
Standard | ValidFAA registration status code V: Valid registration. All codes | |
| N4345K | Piper PA-28-236 |
Fixed-wing, single engine | Bas Part Sales LLC Greeley, Colorado |
Standard | ValidFAA registration status code V: Valid registration. All codes | |
| N44EK | Robinson Helicopter R44 |
Helicopter | Bas Part Sales LLC Greeley, Colorado |
Standard | ValidFAA registration status code V: Valid registration. All codes | |
| N4707S | Cessna TR182 |
Fixed-wing, single engine | Bas Part Sales LLC Greeley, Colorado |
Standard | ValidFAA registration status code V: Valid registration. All codes | |
| N4731P | Piper PA-23-250 |
Fixed-wing, multi-engine | Bas Part Sales LLC Greeley, Colorado |
Standard | ValidFAA registration status code V: Valid registration. All codes | |
| N4811Y | Piper PA-25-235 |
Fixed-wing, single engine | Individual owner Delaware |
Multiple | Sale reportedFAA registration status code 7. All codes | |
| N4831S | Piper PA-32-260 |
Fixed-wing, single engine | Individual owner Alaska |
Standard | PendingFAA registration status code R: Registration pending. All codes | |
| N4836S | Cessna TR182 |
Fixed-wing, single engine | Individual owner Minnesota |
Standard | PendingFAA registration status code R: Registration pending. All codes | |
| N4899P | Piper PA-23-250 |
Fixed-wing, multi-engine | C e S Corporation Charleston, West Virginia |
Standard | RevokedFAA registration status code 22: Revoked, canceled. All codes | |
| N515S | Piper PA-24-250 |
Fixed-wing, single engine | Individual owner Texas |
Standard | Pending cancellationFAA registration status code 19: Registration pending, pending cancellation. All codes | |
| N5180P | Piper PA-24-250 |
Fixed-wing, single engine | Individual owner Missouri |
Standard | PendingFAA registration status code R: Registration pending. All codes | |
| N521TY | Robert T Williams BEARHAWK MODEL 5 |
Fixed-wing, single engine | Individual owner Washington |
Experimental | PendingFAA registration status code R: Registration pending. All codes | |
| N5226Y | Piper PA-23-250 |
Fixed-wing, multi-engine | Individual owner Florida |
Standard | Sale reportedFAA registration status code 7. All codes | |
| N522W | Piper PA-24-250 |
Fixed-wing, single engine | Individual owner Indiana |
Standard | PendingFAA registration status code R: Registration pending. All codes | |
| N5231T | Cessna R182 |
Fixed-wing, single engine | Individual owner Arizona |
Standard | PendingFAA registration status code R: Registration pending. All codes | |
| N5253P | Piper PA-24-250 |
Fixed-wing, single engine | Individual owner Colorado |
Standard | Sale reportedFAA registration status code 17: Sale reported, pending cancellation. All codes | |
| N5446P | Piper PA-24-250 |
Fixed-wing, single engine | Individual owner Texas |
Standard | PendingFAA registration status code R: Registration pending. All codes | |
| N5450P | Piper PA-24-250 |
Fixed-wing, single engine | Individual owner Arizona |
Standard | PendingFAA registration status code R: Registration pending. All codes | |
| N5453T | Cessna TR182 |
Fixed-wing, single engine | Individual owner | Standard | Sale reportedFAA registration status code 7. All codes | |
| N5532J | Piper PA-32-260 |
Fixed-wing, single engine | Individual owner Florida |
Standard | PendingFAA registration status code R: Registration pending. All codes | |
| N559RK | Robinson Helicopter R44 |
Helicopter | Individual owner Wyoming |
Standard | PendingFAA registration status code R: Registration pending. All codes | |
| N56328 | Maule M-5-235C |
Fixed-wing, single engine | Individual owner California |
Standard | PendingFAA registration status code R: Registration pending. All codes | |
| N56335 | Maule M-5-235C |
Fixed-wing, single engine | Maule Air INC Moultrie, Georgia |
Standard | ValidFAA registration status code V: Valid registration. All codes | |
| N5641L | Maule M-5-235C |
Fixed-wing, single engine | Individual owner Colorado |
Standard | CanceledFAA registration status code 18: Sale reported, canceled. All codes | |
| N56500 | Maule M-5-235C |
Fixed-wing, single engine | Bas Part Sales LLC Greeley, Colorado |
Standard | ValidFAA registration status code V: Valid registration. All codes | |
| N5670P | Piper PA-24-250 |
Fixed-wing, single engine | Bas Part Sales LLC Greeley, Colorado |
Standard | ValidFAA registration status code V: Valid registration. All codes | |
| N5866P | Piper PA-24-250 |
Fixed-wing, single engine | Bas Part Sales LLC Greeley, Colorado |
Standard | ValidFAA registration status code V: Valid registration. All codes | |
| N5879N | Rockwell International 114 |
Fixed-wing, single engine | Bas Part Sales LLC Greeley, Colorado |
Standard | ValidFAA registration status code V: Valid registration. All codes | |
| N5907P | Piper PA-24-250 |
Fixed-wing, single engine | Individual owner Kansas |
Standard | Sale reportedFAA registration status code 7. All codes | |
| N601NT | Piper AEROSTAR 601P |
Fixed-wing, multi-engine | Individual owner Florida |
Standard | PendingFAA registration status code R: Registration pending. All codes | |
| N6106P | Piper PA-24-250 |
Fixed-wing, single engine | Individual owner Arizona |
Standard | PendingFAA registration status code R: Registration pending. All codes | |
| N6289P | Piper PA-24-250 |
Fixed-wing, single engine | No owner on file | Standard | Assigned, not yet registeredFAA registration status code 2: N-number assigned but not yet registered. All codes | |
| N6372P | Piper PA-24-250 |
Fixed-wing, single engine | Individual owner Texas |
Standard | ValidFAA registration status code V: Valid registration. All codes | |
| N666AE | Siai-Marchetti SF260 |
Fixed-wing, single engine | Individual owner Florida |
Standard | PendingFAA registration status code R: Registration pending. All codes | |
| N6792Z | Piper PA-25-235 |
Fixed-wing, single engine | Mid Continent Aircraft CORP Hayti, Missouri |
Restricted | ValidFAA registration status code V: Valid registration. All codes | |
| N6857Z | Piper PA-25-235 |
Fixed-wing, single engine | Individual owner California |
Restricted | PendingFAA registration status code R: Registration pending. All codes | |
| N6886P | Piper PA-24-250 |
Fixed-wing, single engine | Bas Part Sales LLC Greeley, Colorado |
Standard | ValidFAA registration status code V: Valid registration. All codes | |
| N6983P | Piper PA-24-250 |
Fixed-wing, single engine | Individual owner New Jersey |
Standard | PendingFAA registration status code R: Registration pending. All codes | |
| N7031Z | Piper PA-25-235 |
Fixed-wing, single engine | Individual owner South Dakota |
Restricted | Sale reportedFAA registration status code 17: Sale reported, pending cancellation. All codes | |
| N7050Z | Piper PA-25-235 |
Fixed-wing, single engine | Mid Continent Aircraft CORP Hayti, Missouri |
Restricted | 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 8, 2026. Horsepower and thrust are the FAA's figures for the series, not for a particular aircraft.