# Service difficulty reports: Allison 501-D22

A list on [Allison 501-D22](https://openairdocs.org/engine/allison-501-d22.md).

Newest first. General aviation reporting is voluntary.

- [SDR VGCA20250513001](https://openairdocs.org/sdr/VGCA20250513001.md): Tach Generator · stripped · May 13, 2025 · N391FL · Cvac STC3405800 · Engine RPM Indicating System
  > RIGHT ENGINE RPM SPOOLED DOWN IN FLIGHT. ENGINE WAS SHUTDOWN. SUBSEQUENT INSPECTION FOUND THAT TACH GENERATOR DRIVE SHAFT WAS SPRIPPED
- [SDR VGCA20241209001](https://openairdocs.org/sdr/VGCA20241209001.md): Check Valve · blocked · Dec 9, 2024 · N351FL · Cvac STC3405800 · Cabin Compressor System
  > ON LANDING SMOKE FILLED CABIN AND COCKPIT. DURING SUBSEQUENT INSPECTION FOUND THAT ENGINE DRIVEN COMPRESSOR (CABIN) HAD OVERHEATED AND DUMPED OIL INTO CABIN AIR INLET DUCT. THE CAUSE FOR THE OVERHEAT CONDITION WAS A FAILED OIL CHECK VALVE.
- [SDR VGCA20240207001](https://openairdocs.org/sdr/VGCA20240207001.md): Reduction Gb · pressure loss · Feb 7, 2024 · N371FL · Cvac STC3405800 · Turbine Engine Reduction Gear
  > REDUCTION GEARBOX HAD INTERNAL FAILURE THAT CAUSED ENTIRE QUANITY OF ENGINE OIL TO FILL REDUCTION GEARBOX.
- [SDR VGCA20220330001](https://openairdocs.org/sdr/VGCA20220330001.md): None · bypassing · Mar 30, 2022 · N351FL · Cvac STC3405800 · Compressor Bleed Control
  > ENGINE COMPRESSOR SURGED AND THEN FLAMED OUT AND AUTOFEATHERED AT THE END OF TAKE OFF PHASE.
- [SDR VGCA20211023001](https://openairdocs.org/sdr/VGCA20211023001.md): Not Reported · not reported · Oct 23, 2021 · N351FL · Cvac STC3405800 · Powerplant System
  > ENGINE FLAMEOUT / LOSS OF POWER DURING CRUISE. ACCESSOPRY DRIVE HOUSING GEARBOX IS NOT ROATATING
- [SDR VGCA20210510001](https://openairdocs.org/sdr/VGCA20210510001.md): Spar · corroded · Apr 28, 2021 · N371FL · Cvac STC3405800 · Wing Spar
  > RIGHT WING, REAR SPAR, UPPER RAIL CORRODED AT WING STATION 23. PERFORMED BLEND OUT IN THIS LOCATION PER ENGINEERING REPAIR.
- [SDR VGCA20210510002](https://openairdocs.org/sdr/VGCA20210510002.md): Spar · corroded · Apr 28, 2021 · N371FL · Cvac STC3405800 · Wing Spar
  > RIGHT WING, REAR SPAR, UPPER RAIL CORRODED BETWEEN WING STATION 21 AND 22. SPLICED IN NEW SPAR RAIL SEGMENT PER ENGINEERING REPAIR.
- [SDR VGCA20210510003](https://openairdocs.org/sdr/VGCA20210510003.md): Spar · corroded · Apr 28, 2021 · N371FL · Cvac STC3405800 · Wing Spar
  > RIGHT WING, REAR SPAR, LOWER RAIL CORRODED BETWEEN WING STATIONS 21 AND 23. PERFORMED BLEND OUT PER ENGINEERING REPAIR
- [SDR VGCA20210311001](https://openairdocs.org/sdr/VGCA20210311001.md): Fire Loop · shorted · Mar 11, 2021 · N361FL · Cvac STC3405800 · Fire Detection
  > RIGHT ENGINE ZONE 1 FIRE WARNING IN FLIGHT, SHUT DOWN ENGINE, RETURNED TO AIRPORT. FOUND 2 SECTIONS OF FIRE DETECTOR LOOP BAD.
- [SDR VGCA202006296001](https://openairdocs.org/sdr/VGCA202006296001.md): Oil System · leaking · Jun 26, 2020 · N361FL · Cvac STC3405800 · Turbine Engine Oil System
  > LOSS OF ALL OIL ON NR 1 ENGINE. SHUT DOWN ENGINE AND DECLARED AN EMERGENCY.
- [SDR CA180103009](https://openairdocs.org/sdr/CA180103009.md): Fire Detector · abnormal · Dec 29, 2017 · Cvac 340CVAC · Fire Detection
  > (CAN) IN FLIGHT, THE AIRCRAFT`S NR 1 ENGINE ZONE 2 FIRE WARNING ACTIVATED. THE FLIGHT CREW ACCOMPLISHED THE ENGINE FIRE WARNING SHUTDOWN PROCEDURE AND CHECKLISTS, WHICH RESULTED IN A PRECAUTIONARY ENGINE SHUTDOWN. AN EMERGENCY WAS DECLARED AND THE AIRCRAFT L
- [SDR VGCA20160311001](https://openairdocs.org/sdr/VGCA20160311001.md): Compressor · stalled · Mar 11, 2016 · N371FL · Cvac STC3405800 · Turbine Engine Compressor Section
  > NUMBER 1 COMPRESSOR STALLED. PRECAUTIONARY SHUTDOWN OF THE NR 1 ENG & RETURNED.
- [SDR LR7A2015091700608](https://openairdocs.org/sdr/LR7A2015091700608.md): Housing · failed · Sep 17, 2015 · N403LC · Lkheed 382G · Propeller Controlling System
  > DURING CRUISE, NR 4 ENGINE FLAMED OUT. SHUTDOWN IAW QRH PROCEDURES. R & R VALVE HOUSING ASSY IAW HN61135.
- [SDR CA150506018](https://openairdocs.org/sdr/CA150506018.md): Drive Gear · misinstalled · May 5, 2015 · Cvac 34030 · Turbine Engine Oil System
  > (CAN) LEFT MAIN PRESS & SCAVENGE OIL PUMP WAS INSTALLED DURING WINTER MX. AT SPRING RUN UP IT WAS NOTED THAT THE LT ENG MAIN OIL PRESS WAS NOT WITHIN SPECIFIED LIMITS. THE OIL PUMP WAS REMOVED & DISASSEMBLED. IT WAS DISCOVERED THAT THE DRIVE GEAR HAD BEEN I
- [SDR CA130828014](https://openairdocs.org/sdr/CA130828014.md): Tire · out of balance · Aug 19, 2013 · Cvac 340CVAC · Tire
  > (CAN) NOSE WHEEL TIRES ON 2 SEPARATE ACFT, REPLACED DUE TO NOSE WHEEL SHIMMY ON EACH ACFT DURING TAKEOFF. 1 TIRE/RIM WAS REPLACED AUGUST 16,2013 AND THE OTHER AUGUST 19TH, 2013. REPLACEMENT OF THESE TIRES REMOVED THE SHIMMY FROM THE ACFT. WHEN TIRES WERE RE
- [SDR CA130718004](https://openairdocs.org/sdr/CA130718004.md): Strut · broken · Jul 17, 2013 · Cvac 340CVAC · Nose/Tail Landing Gear Strut/Axle
  > (CAN) AFTER TAKEOFF WITH A POSITIVE RATE OF CLIMB THE GEAR HANDLE WAS SELECTED UP. A LOUD BANG WAS HEARD AND THE "GEAR UNLOCKED" LIGHT REMAINED ILLUMINATED. THE LOAD WAS JETTISONED AT THE DESIGNATED ABORT SITE. THREE GEAR DOWN SOURCES WERE OBTAINED AFTER SELEC
- [SDR VGCA20130401001](https://openairdocs.org/sdr/VGCA20130401001.md): Propeller · malfunctioned · Apr 1, 2013 · N371FL · Cvac STC3405800 · Propeller System
  > NR 2 PROPELLER AUTOFEATHER AFTER TAKEOFF.
- [SDR CA130128022](https://openairdocs.org/sdr/CA130128022.md): Rod End · worn · Jan 28, 2013 · Cvac 340CVAC · Engine Mount Section
  > (CAN) IN THE SUMMER OF 2011,PILOTS REPORTED THAT AT HIGH POWER SETTINGS IN CRUISE A HIGH FREQUENCY VIBRATION WAS FELT IN THE OTBD RUDDER PEDALS AND THE SEAT FRAMES. IT WAS ALSO NOTICED THAT THE OTBD STATIC WICKS OF THE LT ELEVATOR WOULD BE MISSING AFTER SOME F
- [SDR VGCA201208240001](https://openairdocs.org/sdr/VGCA201208240001.md): Beam · cracked · Aug 24, 2012 · N391FL · Cvac STC3405800 · Fuselage Main, Structure
  > LEFT NOSE LANDING GEAR BEAM UPPER CHORD CRACKED.
- [SDR CA120806002](https://openairdocs.org/sdr/CA120806002.md): Motor · failed · Jul 28, 2012 · Cvac 340CVAC · Air Distribution Fan
  > (CAN) DURING OPERATIONS IN A VERY HOT, 35C+, ENVIRONMENT, THE FAN UNIT OF THE ZEE SYS INC. AIR CONDITIONING SYS WOULD OVERTEMP AND BURN OUT, CREATING A BURNING ODOR AND OCCASIONAL SMOKE IN THE AIR CONDITIONING SYS. THE SYS WAS INSTALLED WHEN THE ACFT WAS CON
- [SDR CA120610001](https://openairdocs.org/sdr/CA120610001.md): Solenoid · failed · Jun 4, 2012 · Cvac 340CVAC · Air Conditioning System
  > (CAN) ON APPROACH, CREW EXPERIENCED A HAZE IN THE COCKPIT AND NOTICED THE, CABIN COMPRESSOR OIL LOW, LIGHT ILLUMINATED. CREW DISCONNECTED THE EDC AND LANDED WITHOUT INCIDENT. MAINTENANCE DISCOVERED 3 SCREWS MISSING FROM THE EDC DUMP SOLENOID VALVE AND REPLAC
- [SDR CA120823012](https://openairdocs.org/sdr/CA120823012.md): Angle · cracked · Apr 2, 2012 · Cvac 340CVAC · Fuselage Miscellaneous Structure
  > (CAN) DURING ANNUAL 375 HR INSPECTION, A CRACK WAS DISCOVERED VISUALLY IN THE NLG WHEEL WELL. MORE SPECIFICALLY, THE CRACK WAS LOCATED IN THE LT SIDE OF THE NLG BEAM, UPPER CHORD FROM FS 53 TO FS 46. THE LENGTH OF THE CRACK WAS DETERMINED BY LPI INSPECTION AF
- [SDR CA120127013](https://openairdocs.org/sdr/CA120127013.md): Fitting · cracked · Jan 25, 2012 · Cvac 340CVAC · Elevator Structure
  > (CAN) DURING A 375 HR ANNUAL INSPECTION ON THE EXTERIOR OF THE EMPENNAGE, ELEVATOR AND HINGE ATTACHING PINS, BEARINGS AND BUSHINGS, THE SECOND FROM THE OTBD LT AND RT HINGE PIN FITTINGS WERE FOUND CRACKED AROUND THE RADIUS OF THE FITTING. FURTHER INVESTIGATIO
- [SDR CA111025011](https://openairdocs.org/sdr/CA111025011.md): Attach Bracket · cracked · Oct 24, 2011 · Cvac 340CVAC · Fuselage Main, Attach Fittings
  > (CAN) DURING ANNUAL INSPECTION, FWD ECP BOX ATTACHMENT BRACKET, FOUND CRACKED IN UPPER AFT CORNER OF STRUCTURE ATTACH POINT. AFT ECP BOX PN 35E05-6D TOP ATTACH POINTS ALSO FOUND BROKEN. THIS IS THE SECOND ACFT IN OUR FLEET, WE HAVE DISCOVERED THIS DAMAGE IN
- [SDR CA110701001](https://openairdocs.org/sdr/CA110701001.md): Relay · wrong part · Jun 16, 2011 · Cvac 340CVAC · Electrical Power System Wiring
  > AFTER STARTING THE NR2 ENGINE, ELECTRICAL SMOKE FUMES DETECTED IN THE COCKPIT. SMOKE CONTINUED TO BUILD. ELECTRICAL FIRE SUSPECTED. THE CREW SHUTDOWN ACFT POWER AND ENGINES. DC BATTERY DISCONNECTED. AFTER SHUTDOWN SMOKE STOPPED. CREW INVESTIGATED SOURCE A
- [SDR CA110413016](https://openairdocs.org/sdr/CA110413016.md): Line · leaking · Apr 9, 2011 · Cvac 340CVAC · Hydraulic System, Main
  > (CAN) ACFT DEPARTED AT ABOUT 1530Z. IN FLIGHT, THE CREW HAD LOST HYD QTY, DECLARED AN EMERGENCY AND RETURNED TO DEPARTURE. ACFT WAS TOWED TO RAMP AND MAINTENANCE DISCOVERED A HYD LEAK COMING FROM THE LT NACELLE AREA. MAINTENANCE FOUND A CHAFED PRESSURE HYD
- [SDR CA101018014](https://openairdocs.org/sdr/CA101018014.md): Hinge Fitting · damaged · Oct 15, 2010 · Cvac 34035 · Elevator Structure
  > DURING THE ANNUAL 375 HR INSP, ELEVATOR/EMPENNAGE INSP PANELS WERE REMOVED. RT ELEVATOR OTBD STABILIZER TO ELEVATOR HINGE FITTING WAS FOUND GROOVED ON TOP RADIUS OF THE FITTING. INVESTIGATION REVEALED THAT THE SCREWS ATTACHING THE RT ELEVATOR END CAP FAIRING
- [SDR CA100521005](https://openairdocs.org/sdr/CA100521005.md): Control Box · failed · May 17, 2010 · Cvac STC3405800 · AC Generator-Alternator
  > NR 1 ENGINE AC GENERATOR CAME OFF LINE DURING CRUISE, GENERATOR RESET AND STILL WILL NOT COME ON LINE, CONTROL BOXES SWAPPED AND FAULT TRANSFERED TO OTHER SIDE AND CONFIRMED. NEW CONTROL BOX INSTALLED AND GENERATOR CAME BACK ON LINE.
- [SDR CA090622015](https://openairdocs.org/sdr/CA090622015.md): Generator · inoperative · Jun 20, 2009 · Cvac 340CVAC · AC Generator-Alternator
  > (CAN) ON APPROACH, PILOT NOTICED NR 1 AC GENERATOR INOP LIGHT ON AND VOLTMETER INDICATED 0 VOLTS. CIRCUIT METERED BACK THROUGH VOLTAGE REGULATOR AND FOUND OPEN FIELD. GENERATOR REPLACED.
- [SDR CA090617008](https://openairdocs.org/sdr/CA090617008.md): Selector Valve · inoperative · Jun 14, 2009 · Cvac 340CVAC · Trailing Edge Flap Control System
  > (CAN) PILOT UNABLE TO RETRACT FLAPS THROUGH NORMAL ELECTRIC FLAP CONTROL SWITCH. FLAPS RETRACTED USING MANUAL EMERGENCY FLAP SELECTOR. TROUBLESHOOTING DETERMINED ELECTRIC SOLENOID WAS WORKING BUT UNABLE TO POSITION VALVE INSIDE SELECTOR TO PORT PRESSURE TO FL
- [SDR CA070824007](https://openairdocs.org/sdr/CA070824007.md): Door · inoperative · Jul 25, 2007 · Cvac 440 · Engine Oil Cooler
  > (CAN) AIRCRAFT WAS DISPATCHED FOR FIRE ACTION. AFTER DEPARTURE, THE RT OIL TEMPERATURE GAUGE WAS OBSERVED TO BE AT THE BOTTOM OF THE RED ARC, APPROXIMATELY 100 DEGREES C. THE FLIGHT CREW IMMEDIATELY SHUTDOWN THE RT ENGINE AS A PRECAUTION AND RETURNED TO BASE.
- [SDR CA070727009](https://openairdocs.org/sdr/CA070727009.md): Lever · distorted · Jul 23, 2007 · Cvac 440 · Landing Gear Selector
  > (CAN) UPON SELECTION OF (GEAR DOWN), THE LOCKING ARM OF THE LANDING GEAR SELECTOR HANDLE STUCK IN THE EXTENDED POSITION, PREVENTING ASSOCIATED FUNCTION OF DEPRESSING THE GEAR WARNING LIGHT SWITCH. THE RESULT WAS NO GEAR DOWN INDICATING LIGHTS ON THE ANNUNCIAT
- [SDR CA070308004](https://openairdocs.org/sdr/CA070308004.md): Control Switch · shorted · Mar 6, 2007 · Cvac 340CVAC · DC Generating System
  > (CAN) WHILE CARRYING OUT FLIGHT TRAINING THE LT GENERATOR WAS TURNED OFF. WHEN SELECTED BACK ON, IT WAS NOTED THAT SMOKE WAS COMING FROM THE VOLTAGE REGULATOR. THE GANG BAR WAS SELECTED TO SHUTOFF DC POWER. DURING TROUBLESHOOTING THE MAINTENANCE CREW DISCOVERE
- [SDR CA060617001](https://openairdocs.org/sdr/CA060617001.md): Steering Sys · malfunctioned · Jun 9, 2006 · Cvac 440 · Landing Gear Steering System
  > AFTER T/O, DURING L/G RETRACTION, NOSE WHEELS ENTERED W/W IN A RT TURN ATTITUDE, EVIDENT FROM WEAR MARKS ON TIRES AND RUBBER ON INTERIOR WALLS OF W/W. WHEN A/C LANDED, NOSE WHEELS WERE STILL TURNED TO THE RIGHT, UNKNOWN TO AIRCREW. CAPT TRIED TO STRAIGHTEN N
- [SDR CA060426003](https://openairdocs.org/sdr/CA060426003.md): Engine · failed · Apr 24, 2006 · Cvac 340CVAC · Engine (Turbine/Turboprop)
  > (CAN) DURING CRUISE, THE CREW NOTICED THE TIT SPIKED TO 1100 DEGRESS F. THE HORSEPOWER DECREASED AND THE ZONE 1 FIRE BELL SOUNDED. THE E HANDLE AWAS PULLED AND THE ENGINE WAS SHUT DOWN AND THE PROPELLER FEATHERED. THE AIRCRAFT LANDED. MAINTENANCE CREW INSPECTE
- [SDR 2005FA0000344](https://openairdocs.org/sdr/2005FA0000344.md): Window · blew out · Feb 22, 2005 · N391FL · Cvac 340CVAC · Flight Compartment Windows
  > DURING CRUISE FLIGHT AT FL230, THE FO SIDE WINDOW BLEW OUT; AT WHICH TIME, AN EMERGENCY DESCENT WAS EXECUTED TO AN UNEVENT LANDING. (K)
- [SDR CA050329014](https://openairdocs.org/sdr/CA050329014.md): Window · failed · Feb 22, 2005 · Cvac 340CVAC · Flight Compartment Windows
  > (CAN) THE OPERATOR HAS FILED AN INCIDENT REPORT WITH THE FAA. WINDOWPANE FAILURE AT CRUISE ALTITUDE OF 21,000 FT, WHICH CAUSED FOD DAMAGE TO THE RT ENGINE. THE WINDOW WAS LAST INSPECTED FEB 14 2005. REASON: COMPLETE FAILURE OF THE VINYL LINER AT THE EDGE OF
- [SDR CA040702005](https://openairdocs.org/sdr/CA040702005.md): Switch · faulty · Jun 22, 2004 · Cvac 340CVAC · Engine Starter
  > (CAN) DURING CRUISE THE LT STARTER OVERSPEED LIGHT ILLUMINATED. THE ENGINE WAS SHUT DOWN AND THE PROPELLER WAS FEATHERED AS A PRECAUTION. THE AIRCRAFT RETURNED TO BASE. THE STARTER WAS REMOVED AND NO DAMAGE WAS NOTED. THE LIGHT SYSTEM WAS CHECKED FOR FAULTS N
- [SDR CA030115007](https://openairdocs.org/sdr/CA030115007.md): Fitting · cracked · Dec 23, 2002 · Cvac 340CVAC · Engine Fuel Distribution
  > TWO HOSE ASSEMBLIES (390A20D4.8 AND 390A20D12.5) FROM A FUEL SUPPLY "Y" MANIFOLD WAS REMOVED AND ROUTED TO OUR INTERNAL OVERHAUL SHOP FOR REPLACEMENT OF THE HOSES. UPON DISASSEMBLY, IT WAS DISCOVERED THAT THREE OF THE FOUR FITTINGS (SOCKETS) (AN212-20D) WERE
- [SDR CA010727017](https://openairdocs.org/sdr/CA010727017.md): Gearbox · leaking · Jul 20, 2001 · Cvac 340CVAC · Turbine Engine Reduction Gear
  > (CAN) DURING CLIMB THROUGH FL170 AFTER DEPARTURE NOTICED NR 2 GEAR BOX OIL PRESSURE FLICKERING. OIL PRESSURE WAS STILL IN THE GREEN RANGE AND THE POWER SECTION OIL PRESSURE WAS NORMAL. ENGINE SHUT DOWN AND AIRCRAFT DIVERTED INTO YYZ.
- [SDR 20010220CW001](https://openairdocs.org/sdr/20010220CW001.md): Propeller · blown · Jan 7, 2001 · N391FL · Cvac 340CVAC · Propeller System
  > AIRCRAFT WAS COLD SOAKED, OUTSIDE TEMPERATURE BEFORE DEPARTURE WAS 15 DEGREES. SUBMITTER FEELS THIS WAS A CONTRIBUTING FACTOR TO THIS SEAL BEING DEFECTIVE. COMPANY INITIATED PROCEDURES NOT TO CHANGE PROP BLADE ANGLE UNTIL MINIMUM OF 40 DEGREE OIL TEMPERATURE
- [SDR CA981125001](https://openairdocs.org/sdr/CA981125001.md): Gearbox · leaking · Apr 9, 1998 · Turbine Engine Accessory Drive
  > (CAN) DURING CLIMB THROUGH FL 170, NR 2 GEARBOX OIL PRESSURE LIGHT FLICKERING. OIL PRESSURE WAS STILL IN THE GREEN RANGE AND THE POWER SECTION OIL PRESSURE LIGHT WAS NORMAL. OIL QUANTITY INDICATION DROPPED RAPIDLY AND THE LOW OIL PRESSURE LIGHT STARTED TO FL
- [SDR CA990310067](https://openairdocs.org/sdr/CA990310067.md): Gearbox · leaking · Apr 9, 1998 · Turbine Engine Accessory Drive
  > (CAN) DURING CLIMB THROUGH FL 170, NR 2 ENGINE GEARBOX LIGHT FLICKERED. OIL PRESSURE WAS STILL IN THE GREEN AND THE POWER SECTION OIL PRESSURE WAS NORMAL. OIL QUANTITY INDICATION DROPPED RAPIDLY AND THE OIL PRESSURE LIGHT STARTED TO FLICKER. THE ENGINE WAS

## The whole list in SQL

Runs in DuckDB 1.2 or later on the release's Parquet files over HTTPS:

```sql
SELECT sdr_id, difficulty_date, n_number, aircraft_make, aircraft_model, part_name, part_condition, jasc_code, discrepancy
FROM 'https://openairdocs.org/data/latest/faa_service_difficulty_report.parquet'
WHERE engine_model_key = '501D22'
ORDER BY difficulty_date DESC
```

This list as a web page: https://openairdocs.org/engine/allison-501-d22/reports

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