# Service difficulty reports: Allison 250-C18

A list on [Allison 250-C18](https://openairdocs.org/engine/allison-250-c18.md).

Newest first. General aviation reporting is voluntary.

- [SDR 2012FA0000550](https://openairdocs.org/sdr/2012FA0000550.md): Flex Coupling · separated · Aug 7, 2012 · N5038F · Hiller 1100 · Tail Rotor Drive Shaft
  > FLEX COUPLING FAILED AT OUTPUT OF INTERMEDIATE GEARBOX. SUBSTATIAL DAMAGE OCCURED DURING HARD LANDING.
- [SDR AU510001641](https://openairdocs.org/sdr/AU510001641.md): Strobe · wrong part · Jul 4, 2005 · Hughes 369A · Exterior Lighting
  > (AUS) INCORRECT STROBE LIGHT FITTED. THE INCORRECT LIGHT WAS APPROXIMATELY 50MM (1.96IN) HIGHER THAN THE ORIGINAL LIGHT. THIS EXTRA HEIGHT BROUGHT THE LIGHT INTO THE TRACKING AREA OF THE MAIN ROTOR BLADES WHICH CONSEQUENTLY IMPACTED ON THE LIGHT CAUSING UNREPA
- [SDR CA041007004](https://openairdocs.org/sdr/CA041007004.md): Gear · worn · Sep 27, 2004 · Bell 206BELL · Turbine Engine Oil System
  > (CAN) THIS IS THE OIL PUMP GEAR THAT DRIVES THE HYDRAULIC PUMP ON THE AC, GREASING INTERVAL IS 300 HRS. THIS SHAFT WAS GREASED EVERY 100 HRS AND HAS TOTALLY WORN OUT. THIS SHAFT ALSO WEARS OUT THE COUPLING IT ATTACHES TO, AS WELL.
- [SDR ERAA080478](https://openairdocs.org/sdr/ERAA080478.md): Governor · malfunctioned · Jul 18, 2002 · N130EH · Bolkms BO105S · Fuel Controlling System
  > TORQUE SPLITS UP TO 30% IN CRUISE FLIGHT. GOVERNOR REPAIRED AND TESTED SERVICEABLE IAW HONEYWELL OHM FORM 15-1095A. CEB'S A-1353R2 AND 1384 FOUND N/A BY UNIT S/N.
- [SDR ERAA080479](https://openairdocs.org/sdr/ERAA080479.md): Turbine Wheel · damaged · Jul 18, 2002 · N135EH · Bolkms BO105A · Turbine Section
  > UNIT HAS LOW POWER. NR 4 NOZZLE AND NR 3 WHEEL CRACKED. INSTALLED NEW NR 3 & 4 WHEEL AND NEW NR 4 NOZZLE. C/W CEB-1360; RE-COAT INNER SHAFT.
- [SDR ERAA080480](https://openairdocs.org/sdr/ERAA080480.md): Diffuser · damaged · Jul 18, 2002 · N131EH · Bolkms BO105S · Turbine Engine Compressor Section
  > ALUMINUM DAMAGED BY IMPELLER. REMOVED AND RE-APPLIED PLASMA SPRAY ON CONTOUR. (OVERHAULED).
- [SDR ERAA080474](https://openairdocs.org/sdr/ERAA080474.md): Shaft · stiff · Jul 17, 2002 · N291EH · Bolkms BO105A · Fuel Controlling System
  > THROTTLE SHAFT STIFF. THROTTLE BUSHING, REPLACED WITH NEW, AND GOVERNOR WAS RE-CALIBRATED TO FINAL CALIBRATION LIMITS.
- [SDR ERAA080475](https://openairdocs.org/sdr/ERAA080475.md): Governor · malfunctioned · Jul 17, 2002 · N130EH · Bolkms BO105S · Fuel Controlling System
  > TORQUE SPLITS - SPEEDS UP AND ADJ MAX BEEP TO 99 PERCENT N2. THEN WAS TEST FLOWN - CHECKED MAX BEEP AT 96 PERCENT - ADJ TO 99 PERCENT AND HOVER A/C MAX BBEP FELL AGAIN TO 95 PERCENT. SENT TO ACRO FOR REPAIR. FOUND EXCESSIVE DROOPING, BEYOND SERVICE LIMITS, R
- [SDR ERAA080476](https://openairdocs.org/sdr/ERAA080476.md): Shaft · stiff · Jul 17, 2002 · N131EH · Bolkms BO105S · Fuel Controlling System
  > STIFF THROTTLE SHAFT. ROUGH/ DRY INTERNAL BEARINGS. ACTION TAKEN: SENT TO ACRO FOR REPAIR. REPAIRED AND TESTED IAW HONEYWELL OHM FORM 15-1095A.
- [SDR HEEA080433](https://openairdocs.org/sdr/HEEA080433.md): Shaft · worn · Jul 11, 2002 · Bell TH57A · Turbine Engine Compressor Section
  > SHAFT HAS SPALLING AND STEP WEAR ON GEAR TEETH BEYOND NORMAL WEAR.
- [SDR HEEA078481](https://openairdocs.org/sdr/HEEA078481.md): Bearing Race · spalled · Mar 29, 2002 · N131 · Bell TH57A · Turbine Section
  > TURBINE WAS REMOVED DUE TO METAL IN OIL. INSPECTION REVEALED SPALLING ON INNER RACE COUPLING BEARING RACE. INSTALLED NEW INNER RACE COUPLING.
- [SDR AUS20020115](https://openairdocs.org/sdr/AUS20020115.md): Bearing · cracked · Jan 18, 2002 · Hughes 369HS · Main Rotor Gearbox
  > (AUS) MAIN TRANSMISSION BEARING INNER RACE SPLIT WITH HEAVY BRINNELLING EVIDENT. METAL CONTAMINATION OF TRANSMISSION OIL SYSTEM.
- [SDR AUS20011238](https://openairdocs.org/sdr/AUS20011238.md): Blade · failed · Nov 14, 2001 · Hughes 369HS · Turbine Engine Compressor Section
  > (AUS) SECOND STAGE COMPRESSOR BLADES (2OFF) FAILED). MAJOR DOWNSTREAM DAMAGE. SEVERAL OTHER SECOND STAGE ROTOR BLADES WERE FOUND TO BECRACKED FROM THE TRAILING EDGE.
- [SDR ERAA092664](https://openairdocs.org/sdr/ERAA092664.md): Seal · fod · Jan 11, 2001 · Bolkms BO105S · Turbine Engine Compressor Section
  > FOD DAMAGE TO SEAL. CONTOUR FOUND DAMAGED AT CYCLE 1 INDUCTION. FULL OVERHAUL INCLUDING CONTOUR RESTORATION.
- [SDR CA990915064](https://openairdocs.org/sdr/CA990915064.md): Attach Ring · broken · Sep 3, 1999 · Hughes 369HE · Rotorcraft Tail Boom
  > (CAN) THE HORIZONTAL FORWARD ATTACHMENT RING ON THE TAILBOOM WAS FOUND BROKEN OFF.
- [SDR 99ZZZX3280](https://openairdocs.org/sdr/99ZZZX3280.md): Bearing · galled · Aug 10, 1999 · N370FH · Hiller FH1100 · Turbine Engine Compressor Section
  > BEARING FOUND GALLED IN ENGINE COMPRESSOR SECTION.
- [SDR ERAA062391](https://openairdocs.org/sdr/ERAA062391.md): Case · mismanufactured · May 13, 1999 · N148EH · Bolkms BO105A · Turbine Engine Combustion Section
  > OUTER COMBUSTION CASE COULD NOT BE INSTALLED BECAUSE AIR TUBE BOSS IS.008 INCH OUT OF ROUND.
- [SDR ERAA062371](https://openairdocs.org/sdr/ERAA062371.md): Shield · cracked · Apr 21, 1999 · N141LG · Bolkms BO105A · Fuel Injector Nozzle
  > TURBINE DUE 1,750 HOUR INSPECTION DUE TO NR 1 AND NR 2 WHEEL CYCLE OUT. DISCOVERED CONDITION OF NR 1 NOZZLE SHIELD DURING TEARDOWN. THE DAMAGE STARTS AT THE MISSING MATERIAL TO HALF THE CIRCUMFERENCE OF THE DOME. CRACK IS LOCATED WHERE THE DOME IS BRAZED
- [SDR ERAA061869](https://openairdocs.org/sdr/ERAA061869.md): Sump Cover · mismanufactured · Apr 16, 1999 · N148EH · Bolkms BO105A · Turbine Section
  > SUMP COVER COULD NOT BE INSTALLED DUE TO LOOSE DEBRIS AND FLAKING OVERSPRAY INSIDE OF COVER. ONE HOLE CLOGGED.
- [SDR ERAA061867](https://openairdocs.org/sdr/ERAA061867.md): Gp Support · misoverhauled · Apr 12, 1999 · N148EH · Bolkms BO105A · Turbine Section
  > GP SUPPORT SENT FOR OVERHAUL 8-4-98, COULD NOT BE INSTALLED DUE TO ROUGH SURFACE AT NR 8 OIL TUBE SEAL, AND SUMP NUT E-RING SEAT.
- [SDR ERAA061862](https://openairdocs.org/sdr/ERAA061862.md): Nut · leaking · Mar 24, 1999 · N148EH · Bolkms BO105A · Turbine Engine Compressor Section
  > NEW NUT; CAP LEAKS.
- [SDR CA980804009](https://openairdocs.org/sdr/CA980804009.md): Fan · wrong part · Jul 16, 1998 · Hughes 369HS · Starter-Generator
  > (CAN) IN SHOP FOR REPAIR, LEAR SIEGLER STARTER/GENERATOR HAD AN APC FAN P/N 1503G1107 INSTEAD OF THE LEAR SIEGLER FAN P/N 23032-1481.
- [SDR CA980507006](https://openairdocs.org/sdr/CA980507006.md): Clamp · cracked · May 6, 1998 · Hughes 369HE · Engine Collector/Tailpipe/Nozzle
  > (CAN) EXHAUST COLLECTOR WELDED MARON CLAMP RING FOUND CRACKED.
- [SDR 97ZZZX206](https://openairdocs.org/sdr/97ZZZX206.md): Hose · leaking · Dec 11, 1996 · N7929J · Bell 206B · Engine Fuel Distribution
  > ENGINE DRIVEN FUEL PUMP INLET LINE LEAKING AT FLARE FITTING DUE TO A CRACK. REPLACED WITH SERVICEABLE LINE.
- [SDR AU960191](https://openairdocs.org/sdr/AU960191.md): Drive Shaft · sheared · Feb 15, 1996 · Hughes 369HS · Tail Rotor Drive Shaft
  > (AUS) TAIL ROTOR DRIVE SHAFT SHEARED APPROXIMATELY 457.2MM (18IN) FROM THE FORWARD END - SEVERAL LONGITUDINAL CRACKS WERE EVIDENT IN THEAREA OF THE FAILURE WHEN VIEWED UNDER X10 MAGNIFICATION
- [SDR AU960192](https://openairdocs.org/sdr/AU960192.md): Housing · corroded · Feb 15, 1996 · Hughes 369HS · Vertical Stabilizer
  > (AUS) STABILIZER STRUT DAMPER SHAFT PULLED FROM FITTING DURING HEAVY VIBRATION FOLLOWING TAIL ROTOR DRIVE SHAFT FAILURE (MDR 96/0191) - FITTING EXHIBITED SIGNS OF SEVERE INTERGRANNULAR CORROSION - AIRCRAFT OPERATES IN A SALT LADEN ENVIRONMENT
- [SDR AU960152](https://openairdocs.org/sdr/AU960152.md): Blade · failed · Feb 2, 1996 · Bell 47G3B1 · Turbine Engine Compressor Section
  > (AUS) COMPRESSOR NO2/3 ROTOR ASSEMBLY BLADE FAILED - BLADES EXITED THROUGH BOTH COMPRESSOR CASE HALVES - FURTHER DAMAGE TO TURBINESECTION DUE TO FOD AND OVERTEMPERATURE - AIRCRAFT IS A SOLOY TURBINE ENGINE MODIFICATION ALLISON 250C18B POWERED BELL 47G3B1

## 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 = '250C18'
ORDER BY difficulty_date DESC
```

This list as a web page: https://openairdocs.org/engine/allison-250-c18/reports

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