Allison 250-C20B
Service difficulty reports · 1,981
Newest first. General aviation reporting is voluntary.
Query with SQL
duckdb -csv -c "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 = '250C20B' ORDER BY difficulty_date DESC"
Prints the whole list as CSV. It reads the release’s Parquet files over HTTPS, so there’s nothing to download first. Install DuckDB to run it.
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 = '250C20B' ORDER BY difficulty_date DESC
Run it at the DuckDB prompt, or in any tool that reads Parquet over HTTPS. More ways to query the release are on Use the data.
SDR CA960619026O-Ring · leaking(CAN) UPPER MAIN ROTOR TRANSMISSION O-RING LEAKING. AS TRANSMISSION WARMED TO OPERATING TEMPERATURE THE NEW PAINT MELTED AND UNSEATED O-RING.SDR CA960619027Clutch · bearing loose(CAN) STEADY BEARING HOUSING SPINNING IN OVERRUNNING CLUTCH HOUSING DUE TO BEARING VIBRATING. BEARING WAS SPINNING UNDER SNAP RING CAUSING ALUMINUM BEARING HOUSING TO WEAR AND CONTAMINATE BEARING WITH METAL SHAVINGS.SDR CA960712106Lead Lag Link · cracked(CAN) CRACK FOUND ON EAR OF LEAD - LAG LINK. FROM BOLT HOLE TO EDGE.SDR CA960712107Window · departed(CAN) PILOT NOTICED INCREASED NOISE FOLLOWED BY WINDOW AND SEAL DEPARTING AIRCRAFT. IT IS BELIEVED THAT WINDOW WAS PROBABLY INSTALLED FROM OUTSIDE OF DOOR INSTEAD OF FROM INSIDE DOOR FRAME.SDR ERAA96245Housing · defectiveHOUSING WAS O/H AND RECEIVED BACK AT ERA 6-6-96. OIL FILTER HOUSING STAYS IN OIL BY-PASS MODE.SDR ERAA96244Exhaust Collecto · mis repairEXHAUST COLLECTOR SENT FOR OVERHAUL 3-18-96 AND RETURNED WITH 4TH NOZZLE TIGHT FIT INTO COLLECTOR.SDR AU960778Trunnion · cracked(AUS) MAIN ROTOR HUB TRUNNION CRACKED IN RADIUS - FAILURE ANALYSIS GROUP COULD FIND NO EVIDENCE OF CRACKING USING BOTH FLUORESCENTDYE PENETRANT AND MAGNETIC PARTICLE INSPECTION TECHNIQUES - THERE WAS EVIDENCE OF REWORK BY POLISHING - PART RETURNED TO BELLHELISDR HEEA967386Pt Support · plating flakeUPON INSPECTION OF PART NOTED THE FOLLOWING: PLATING COMING OFF P.T. SUPPORT INNER SUMP SURFACE U-RING SEAT. REPLACED DISCREPANT PART.SDR HEEA967380Wheel · blade erodedENGINE REMOVED DUE TO HIGH CYCLED 1ST,2ND AND 3RD STAGE WHEEL. UPON INSPECTION OF TURBINE PARTS NOTED THE FOLLOWING: MINOR SULFIDATION ON 7 EACH 1ST STAGE WHEEL BLADES AND ERODED LEADING EDGES. SCRAPPED 1ST STAGE WHEEL.SDR HEEA967310Tie Bolt · mis mfgUPON INSTALLATION NOTED THE FOLLOWING: UNABLE TO ENGAGE THREADS INTO 1ST STAGE WHEEL. UPON INSPECTION OF PART NOTED THE FOLLOWING: IMPROPERLY MACHINED THREADS ON TIE BOLT FWD END.SDR CA970311034Intercostal · cracked(CAN) INTERCOSTAL CRACKED ON UPPER TURTLEBACK SKIN BETWEEN STN 137.5 AND 146.62 ON THE RIGHT HAND SIDE.SDR HEEA967270Spline Adapter · frettedENGINE REMOVED DUE TO COMPRESSOR OVERHAUL. UPON INSPECTION OF COMPRESSOR PARTS NOTED THE FOLLOWING: FRETTING BEYOND OVERHAUL LIMITS ON SPLINED ADAPTER O.D. REPLACED DISCREPANT PART.SDR CA960605001Wind Deflector · debonded(CAN) WHILE SLIDING PASSENGER DOOR WINDOW TO THE CLOSED POSITION THE WIND DEFLECTOR DEBONDED AND CAME OFF THE AIRCRAFT STRIKING THE HORIZONTAL STABILIZER.SDR AU960812Clamp · failed(AUS) ENGINE EXHAUST CLAMP FAILED IN RIVETTED AREA DUE TO CORROSION FROM EXHAUST GASSESSDR CA960604009Disk Assembly · defective(CAN) AFTER COMPLETING A 100 HOUR AND BALANCING THE TAIL ROTOR A VIBRATION WAS FELT THROUGH THE PEDALS. FURTHER TROUBLESHOOTING REVEALED THE DISK ASSEMBLY WAS NOT AS STIFF AS ON OTHER AIRCRAFT. DISK ASSEMBLY CHANGED, VIBRATION DISAPPEARED.SDR HEEA967251Blades · brokenENGINE REMOVED DUE TO OIL LEAK FROM #1 BEARING AREA AND SMOKING. UPON INSPECTION OF COMPRESSOR PARTS NOTED THE FOLLOWING: 2 EACH BLADES BROKEN OFF .250 AND .365 FROM 2ND-3RD STAGE WHEEL BLADE ROOT AREA. FRONT SUPPORT EXHIBITS 5 EACH VANES DISLODGED FROM HUBSDR HEEA967252Nozzle · crackedENGINE REMOVED DUE TO LOW POWER AND SMOKING. UPON INSPECTION OF TURBINE PARTS NOTED THE FOLLOWING: CRACKED BEYOND SERVICEABLE LIMITS ON 1ST STAGE NOZZLE VANE. REPLACED DISCREPANT PART. PHI REQUESTING 100% WARRANTY REPAIR. PART OVERHAULED ON DALLAS AIRMOTISDR ERAA96242Wheel · blade stretchWHEEL HAS 252.0 HRS ON IT AND HAS BLADE TIP STRETCH TO 6.197".SDR 96ZZZX5363Inner Shaft · pittedTHE DEFECT DESCRIBED BELOW WAS DISCOVERED DURING INSPECTION OF THE PART ON RECEIPT FROM A 3RD PARTY VENDOR. THE ALLISON GAS TURBINE 250-C20 SERIES OVERHAUL MANUAL, TABLE VI-19, PAGE 6-114, PROVIDES INSPECTION CRITERIA FOR POWER TURBINE INNER SHAFTS. ITEM 27ASDR HEEA967234Nozzle Diaphragm · crackedTURBINE REMOVED DUE TO CYCLED OUT #1 AND #2 WHEELS. UPON INSPECTION OF TURBINE PARTS NOTED THE FOLLOWING: CRACKED BEYOND OVERHAUL LIMITS ON 2ND STAGE NOZZLE DIAPHRAGM. REPLACE DISCREPANT PART.SDR HEEA967227Nozzle · crackedENGINE REMOVED DUE TO EXCESSIVE SMOKE ON SHUTDOWN. UPON INSPECTION OF TURBINE PARTS NOTED THE FOLLOWING: CRACKED AND BOWED BEYOND SERVICEABLE LIMITS ON #1 NOZZLE VANES. REPLACED DISCREPANT PART.SDR HEEA967228Nozzle Vanes · crackedENGINE REMOVED DUE TO STRIPPED THREADS IN OIL OUT PORT. TURBINE DISASSEMBLED DUE TO LOW POWER ON TEST CELL. UPON INSPECTION OF TURBINE PARTS NOTED THE FOLLOWING: CRACKED BEYOND SERVICEABLE LIMITS ON NR 1 NOZZLE VANES. REPLACED DISCREPAN T PART.SDR HEEA967229Nozzle · crackedTURBINE REMOVED DUE TO LOW POWER ON TEST CELL. UPON INSPECTION OF TURBINE PARTS NOTED THE FOLLOWING: CRACKED BEYOND SERVICEABLE LIMITS ON #2 NOZZLE BRAZEMENT BETWEEN DIAPHRAGM AND VANE INNER BAND. REPLACED DISCREPANT PART.SDR CA960604019Actuator · shorted(CAN) AFTER INSTALLATION OF ACTUATOR THE INITIAL TEST RESULTED IN THE CIRCUIT BREAKER TRIPPING, DIODE 1N4007 SHORTED AND RELAY W25OD4A FAILED.SDR 96ZZZX2935Rotor Assy · defectivePOWER CHECK RESULTS - LOW POWER. COMPRESSOR ASSY REPLACED, DISCREPANCY CLEARED. (ALLISON MODEL 250 REPORT NR A 134718).SDR CA960514106Door Window · failed(CAN) HELICOPTER IN CRUISE, APPROXIMATELY 120 KNOTS, WHEN PILOTS WINDOW IMPLODED THEN EXITED AND SHATTERED.SDR HEEA967098Case Halves · excess rubENGINE REMOVED DUE TO N1 LOCKUP. UPON INSPECTION OF COMPRESSOR PARTS NOTED THE FOLLOWING: PLASTIC LIFTING AND EXCESSIVE RUB IN CASE HALVES FIRST STAGE AREA. REPLACED CASE HALVES.SDR CA960606011Locking Pin · loose(CAN) PIP PIN USED TO HOLD BLADE BOLT IN BLADE FOLDING SETUP, MISSING BALL BEARINGS.SDR CA960801501Mount · cracked(CAN) DURING AN ANNUAL INSPECTION, CRACKS WERE FOUND AT THE ATTACHMENT POINTS OF THE ENGINE FORWARD SUPPORTS. FORWARD ENGINE LEG SUPPORTS FITTINGS AND STIFFENERS 206-031-629-103 AND 206-031-201-291 REPLACED. ENGINE MOUNT SUPPORT CHANNEL AND FRAME 206-031-302-2SDR CA960924032Crosstube · cracked(CAN) DURING ANNUAL INSPECTION AFT CROSSTUBE SUPPORT STRUCTURE FOUND CRACKED AND CORRODED.SDR CA960619010Transmitter · float jams(CAN) FUEL QUANTITY INDICATION WOULD STICK AT APPROXIMATELY 60-65 GALLONS WHEN TANK IS FULL. REMOVAL OF THE LOWER QUANTITY TRANSMITTER REVEALED A BROKEN SOLDER JOINT ALLOWING THE FLOAT TO TWIST APPROXIMATELY 45 DEGREES WHICH ALLOWED FLOAT TO JAM WHILE CONTACTISDR 96ZZZX2586Turbine · nozzle failedDURING CRUISE FLIGHT, TORQUE YAW WAS EXPERIENCED ALONG WITH TOT RISES TO 890 DEGREES CELSIUS. TORQUE WAS REDUCED TO 60 PERCENT AND TOT STABILIZED TO 800 DEGREES CELSIUS. PILOT RETURNED TO OIL PLATFORM WHERE HE SAFELY LANDED. INSPECTION OF ENGINE REVEALED NRSDR 96ZZZX2482Wheel · shroud crackedTURBINE WAS DISASSEMBLED AS PART OF ENGINE REPAIR FOR COMPRESSOR STALLS. FOUND THE SHROUD ON THE THIRD STAGE WHEEL CRACKED ALL THE WAY THROUGH.SDR HEEA967078Shaft · defectiveUPON INSPECTION OF NEW PART NOTED THE FOLLOWING: ALSEAL COATING FLAKING ON OUTER PT SHAFT O.D.SDR 96ZZZX2595Gearshaft Race · spalledTHE RACE OF THIS SPUR ADAPTER GEARSHAFT SUPPORTS THE TWO AND ONE-HALF BEARING. THE TWO AND ONE-HALF BEARING CAGE FAILED SPALLING THE RACE. THIS GEARSHAFT DRIVES THE TURBINE AND COMPRESSOR. THIS IS AN FAA PMA PART MFG BY SUPERIOR PARTS.SDR 96ZZZX3417Governor · defectiveGOVERNOR REQUIRED TO BE RETRIMMED FREQUENTLY, THEN ENGINE FELL TO IDLE ON DESCENT FOR FINAL. GOVERNOR WAS CLOSE TO OVERHAUL, 56.0 HOURS LEFT. REPLACED GOVERNOR.SDR 96ZZZX3841Servo · failedSERVO MOTOR FAILED IN-FLIGHT. MOTOR SHORTED OUT CAUSING CIRCUIT BREAKER TO TRIP.SDR HEEA967042Shaft · defectiveUPON INSPECTION OF NEW OUTER PT SHAFT NOTED THE FOLLOWING: ALSEAL COATING FLAKING ON SHAFT O.D. NEW PART INSTALLED.SDR CA960422007Warning Panel · chafed wire(CAN)THE MAIN FUEL PUMP SWITCH MONITOR LIGHT REMAINED ON WHEN BOOST PUMP WAS ON. AME FOUND WIRE CHAFED ON THE CENTRE CONSOLE, CORNER ANGLE. THIS IS A COMPANY MODIFICATION/INSTALLATION.SDR CA960502025Governor · leaking(CAN) LEAKING PURPLE GREASE FROM INPUT.SDR CA960502026Fcu · failure(CAN) FCU WILL NOT HOLD GROUND IDLE. LEAKING PURPLE GREASE FROM INPUT. FCU REPLACED AND AIRCRAFT RETURNED TO SERVICE.SDR CA960530003Driveshaft · torn boot(CAN) RUBBER BOOT COMPLETELY TORN.SDR HEEA966984Combustion Liner · defectiveUPON ATTEMPTING ASSEMBLY FOUND THE IGNITOR AND FUEL NOZZLE BORE DO NOT ALIGN WITH NUMEROUS COMBUSTION CASES.SDR CA960502030Pitch Link · loose bearing(CAN) SPHERICAL BEARING ON ONE END WAS FOUND HALF WAY OUT OF PITCH LINK.SDR CA960412018Monitor Light · chafed(CAN) MAIN FUEL PUMP SWITCH MONITOR LIGHT WOULD BE ON INTERMITTENTLY. FOUND WIRES CHAFED AGAINST VERTICAL CONSOLE POST. THIS WAS A COMPANY APPROVED MODIFICATION.SDR CA960502027Fcu · failure(CAN) TIME THIS INSTALLATION 144.5 HOURS. BLUE GREASE LEAKING FROM BEARING. STAGNATED STARTS WHICH COULD NOT BE ADJUSTED USING FCU ADJUSTMENTS (ALREADY AT THE LIMITS). THIS FCU HAS PREVIOUS HISTORY FOR REMOVAL FOR SIMILAR REASON. FCU REPLACED AND AIRCRAFT RETUSDR ERAA96215Nozzle · mis ohauledNOZZLE WAS OVERHAULED AND RETURNED TO ERA 1-11-96. #2-4 SEAL NOT SEATED.SDR 96ZZZX1832Governor · erraticTHIS IS THE SECOND TIME THIS UNIT HAS BEEN REMOVED FOR ERRATIC CONDITION. PILOT MUST MAKE CONSTANT ADJUSTMENTS TO THE GOVERNOR 'BEEP' WITH EVERY POWER CHANGE.SDR ERAA96214Coupling · mis mfgNEW PART WITH PILOT DIAMETER TOO SMALL, WOULD NO FIT DOWN OVER OUTER SHAFT TO REACH THREADS. TURBINE WAS BEING O/H WHEN DESCREPANCY WAS FOUND. PART WAS NEVER INSTALLED.SDR 96ZZZX2367Bearing · failedCHIP LIGHT ILLUMINATED IN-FLIGHT. SHORTLY THEREAFTER, ENGINE FAILED. MAINTENANCE FOUND THE BEARINGS ON EITHER END OF THE FUEL CONTROL AND OIL PUMP SPUR GEARSHAFT FELL APART STOPPING FUEL CONTROL OPERATION. EXACT CAUSE UNKNOWN AT THIS TIME. UNUSUAL BECAUSE
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