# Service difficulty reports: JASC 8300

A list on [JASC 8300](https://openairdocs.org/jasc/8300.md).

Reports filed under 8300 · Accessory Gearboxes, newest first.

Page 1 of 7 · 306 reports

- [SDR DBCA202608190001](https://openairdocs.org/sdr/DBCA202608190001.md): Gearbox · contaminated · Aug 6, 2026 · N279AH · Pilats PC24
  > RT EGINE ROLL BACK ON CLIMB OUT. EMERGENCY DECLARED BY CREW, AIRCRAFT RETURNED TO DEPARTURE AIRPORT (135 MED FLIGHT) PATIENT ALREADY DROPPED OFF, ONLY 2 FLIGHT NURSES AND 2 CREW ON BOARD. ONSITE INVESTIGATION BY HOME BASE MX TEAM FOLLOWING DAY REVEALED EXCESS
- [SDR DALA2026072304302](https://openairdocs.org/sdr/DALA2026072304302.md): Alternator · detached · Jul 21, 2026 · N361NW · Airbus A320212
  > RETURNED TO DTW DUE TO LOSS OF NBR 2 ENGINE OIL QUANTITY AND PRESSURE. CREW SHUT ENGINE DOWN WHEN QUANTITY AND PRESSURE WENT TO ZERO. MTC FOUND ENGINE CONTROL ALTERNATOR DETACHED FROM AGB MOUNTING PAD. MAINTENANCE IN PROGRESS. (LP: 8844868. AIRCRAFT WAS GROU
- [SDR N6WA2026070205](https://openairdocs.org/sdr/N6WA2026070205.md): Gearbox · binding · Jun 30, 2026 · N536GJ · Cndair CL6002C11
  > N1, ITT, N2, THRUST FLUCTUATIONS IN FLIGHT AT HIGH THRUST SETTINGS ON RH ENG. PERFORMED BORESCOPE OF THE NR 2 ENG IAW AMM 72-00-0. UPON FURTHER INSPECTION FOUND THE AGB TO BE BINDING.
- [SDR 2026F00138](https://openairdocs.org/sdr/2026F00138.md): Carbon Seal · leaking · Jun 29, 2026 · N652UA · Boeing 767322
  > DURING CRUISE THE A/C FACE RT OIL PRESSURE LT INTERMITTENT ILLUMINATION AND RT ENG QTY INDICATION 0. OIL PRESS FLUCTUATES DOWN 1 TO 27 TEMP NORMAL. CREW REPORTED THAT APPROXIMATELY TWO HOURS PRIOR TO ARRIVAL, INTERMITTENT ENG2 OIL PRESSURE WARNING INDICATIONS
- [SDR 2026F00066](https://openairdocs.org/sdr/2026F00066.md): Seal · leaking · Mar 28, 2026 · N966AM · Boeing 7878
  > LOW OIL QTY INDICATION WITH LOW PRESSURE INDICATION, UNSCHEDULED LANDING, VFSG LH OF ENGINE NR 1 WAS REPLACED IAW AMM DMC B787-A-24-21-09-00B-520A-A/720A-A. ENGINE VENTS AND DRAINS INSPECTION WAS PERFORMED IAW DMC-B787-A-G71-00-00A-280A-A, REPLACEMENT OF
- [SDR DALA2025110908156](https://openairdocs.org/sdr/DALA2025110908156.md): Gearbox · making metal · Nov 7, 2025 · N537DT · Airbus A321271NX
  > DIVERTED TO MCO DUE TO RIGHT ENGINE OIL LOSS AND N2 VIBES. INSPECTED MCD'S AND FOUND METAL ON AGB, NR 3 AND 4 MCD'S. REPLACED RIGHT ENGINE. (LP 7657484, 1291223)
- [SDR ASMF2025111100304](https://openairdocs.org/sdr/ASMF2025111100304.md): Seal · leaking · Nov 2, 2025 · N966AM · Boeing 7878
  > DURING WALKAROUND FOUND SIGNS OF OIL LEAKS COMING FROM HEATER DRAIN VFSG RIGHT PAD ON ENGINE 2. SIX DROPS PER MINUTE. RIGHT VFSG ACCESORY GEARBOX SEAL ENG # 2 WAS REPLACED IAW AMM DMC-787-A-G72-64 -01-00A-520A-A /
- [SDR 2025FA0000687](https://openairdocs.org/sdr/2025FA0000687.md): Bearing · spalled · Oct 7, 2025 · N320MC · Swrngn SA227AC
  > IDLER GEAR [PN: 896804-2] TEETH GALLED DUE TO BEARINGS (2EA) [PN: 3103035-1, SN: 10-151725-07307 & 10-151725-07323, TSN: 5,558.3] WORN AND SPALLING. RESULTED IN UNCOMMANDED SHUTDOWN OF ENGINE DUE TO FUEL PRESSURE LOSS.
- [SDR CALA2025090308441](https://openairdocs.org/sdr/CALA2025090308441.md): Gearbox · contaminated · Aug 31, 2025 · N69833 · Boeing 737924ER
  > NUMBER 1 ENG OIL FILTER BYPASS OCCURED ATFL270 300KIAS, DELCARED EMERGENCY LANDING. DURING INSPECTION, FOUND DEBRIS ON AGB/TGB SCAVENGE MCD. EXAMINED STARTER MAGNETIC PLUG CONTAMINATION REF AMM TASK 79-00-00-200-804-F00. NO PARTICLES FOUND.
- [SDR NACA2025031300007](https://openairdocs.org/sdr/NACA2025031300007.md): Housing · leaking · Mar 13, 2025 · N321CM · Boeing 767323
  > FUEL LEAK #1 ENGINE ACCESSORY GEARBOX FORWARD MID LOWER MAIN FUEL CONTROL HOUSING. LEAK CHECK, NO LEAK FOUND.
- [SDR FXTA20250404003](https://openairdocs.org/sdr/FXTA20250404003.md): Pressure Switch · failed · Feb 19, 2025 · N408BA · Textrn 408
  > PROP DE-ICE CAS MESSAGE ON RUN-UP. FOUND LH & RH LOW OIL PRESSURE SWITCHES WERE FAILED.
- [SDR 2025FA0000115](https://openairdocs.org/sdr/2025FA0000115.md): Shaft · worn · Feb 18, 2025 · Cessna 208B
  > ACCESSORY GEAR AND DRIVE IDLER ASSEMBLY [PN: 3103599-2, SN: 10P27504] FOUND DAMAGED DURING 7,000 HOUR OVERHAUL PERIODIC INSPECTION. DAMAGE FOUND DURING INSPECTION INCLUDED SPLINED SHOULDERED SHAFT [PN: 3103405-3] SPLINES AND SHAFT SURFACES WORN. SPUR GEAR [PN:
- [SDR 2024FA0000972](https://openairdocs.org/sdr/2024FA0000972.md): Bearing · wrong part · Dec 19, 2024
  > ON OCTOBER 8 2024, AGB (ENGINE LEAP 1A) P/N 362-001-242-0 S/N 1P000802 WAS RECEIVED BY STS MAINTENANCE ORGANIZATION (EASA FR.145.0229, FAA H31Y132O) FOR INSPECTION/REPAIR AND MODIFICATION (NOT RELATED TO THIS EVENT) FROM CUSTOMER. THIS AGB WAS NEVER SERVICED
- [SDR 2024F00312](https://openairdocs.org/sdr/2024F00312.md): Gearbox · damaged · Dec 9, 2024 · Boeing 737
  > ON 2024-11-26, DURING THE DISASSEMBLY OF, IT WAS DISCOVERED THAT THREE 'TEN-POINTS NUTS' WHERE MISSING ON LINE 4, ON THE COVER SIDE (P/N J626P04). CONSEQUENTLY, THE OIL RETAINING RING WAS NOT FIXED INTO POSITION. PIECES OF IT WERE TORN OFF AND FOUND AT THE B
- [SDR ZD4R202410040001](https://openairdocs.org/sdr/ZD4R202410040001.md): Shaft · broken · Oct 4, 2024 · N36VA · Bell 407
  > DISASSEMBLED GEARBOX AND FOUND 2 BROKEN TEETH ON TORQUEMETER GEARSHAFT. GEAR TEETH WERE LOCATED AT BOTTOM OF GEARBOX. MINOR METAL DEBRIS FOUND ON MAGNETIC CHIP DETECTORS. MINOR DAMAGE TO GEARBOX COVER AND HOUSING ASSEMBLY.
- [SDR 2024FA0000557](https://openairdocs.org/sdr/2024FA0000557.md): Spur Gear · cracked · Aug 1, 2024
  > IN FLIGHT SHUTDOWN OF ENGINE [TPE331-12UHR-702H, PN: 3103380-53]. SPUR GEAR CRACKED / MISSING TEETH [PN: 3103406-2] CAUSING LOSS OF FUEL.
- [SDR DALA2024071107038](https://openairdocs.org/sdr/DALA2024071107038.md): Scavenge Pump · faulted · Jul 10, 2024 · N667DN · Boeing 757232
  > SHIP 667-ATB/IFSD/DE- PERFORMED AIR TURN BACK WITH DECLARED EMERGENCY DUE TO LEFT ENGINE OIL TEMP IN THE AMBER BAND FOR 20 MINUTES. FLIGHT CREW PERFORMED IFSD PER QRH. CORRECTIVE ACTION: INSPECTED MCD'S, ALL CLEAN. DRAINED 4 QUARTS FROM MAIN GEARBOX. REPLACED
- [SDR DALA2024070506818](https://openairdocs.org/sdr/DALA2024070506818.md): Gearbox · making metal · Jul 3, 2024 · N6711M · Boeing 757232
  > SHIP 6711 -DIV/IFSD/DE- DIVERSION TO MSY DUE TO RIGHT ENGINE OIL FILTER ADVISORY MESSAGE. CREW FOLLOWED QRH AND SHUTDOWN ENGINE. CORRECTIVE ACTION: INSPECTED MCD'S AND OIL FILTER, FOUND METAL DEBRIS ON MAIN AND GEARBOX MCDS. ANALYZED MATERIAL AND FOUND 52100 B
- [SDR DALA2024070506817](https://openairdocs.org/sdr/DALA2024070506817.md): Gearbox · making metal · Jul 3, 2024 · N6711M · Boeing 757232
  > SHIP 6711 -DIV/IFSD/DE- DIVERSION TO MSY DUE TO RIGHT ENGINE OIL FILTER ADVISORY MESSAGE. CREW FOLLOWED QRH AND SHUTDOWN ENGINE. CORRECTIVE ACTION: INSPECTED MCD'S AND OIL FILTER, FOUND METAL DEBRIS ON MAIN AND GEARBOX MCDS. ANALYZED MATERIAL AND FOUND 52100 B
- [SDR DALA2024050805029](https://openairdocs.org/sdr/DALA2024050805029.md): Gearbox · overserviced · May 6, 2024 · N408DX · Airbus A330941
  > SHIP 3408 DIRTY SOCK SMELL. CORRECTIVE ACTION: ENGINE GEARBOX WAS OVERFILLED WITH OIL. DRAINED AND RE-FILLED TO CORRECT LEVEL. CLEANED ALL OVERFLOW OIL. REPLACED CABIN FILTERS. OK FOR SERVICE. (0329644)
- [SDR 2024F00048](https://openairdocs.org/sdr/2024F00048.md): Gearbox · abnormal · Mar 4, 2024
  > ON 21 FEBRUARY 2024, SAFRAN TRANSMISSION SYSTEM APPROVED MAINTENANCE ORGANISATION (EASA FR.145.0229, CAAC F03300629, FAA H31Y132O), WHILE DISASSEMBLING ACCESSORY GEARBOX (AGB), P/N 340-046-508-0, S/N WZ7492, FOR AN UNRELATED MAINTENANCE OPERATION, DETECTED THA
- [SDR 2024F00047](https://openairdocs.org/sdr/2024F00047.md): Gearbox · abnormal · Mar 4, 2024
  > ON 19 FEBRUARY 2024, SAFRAN TRANSMISSION SYSTEM APPROVED MAINTENANCE ORGANIZATION (EASA FR.145.0229, CAAC F03300629, FAA H31Y132O), WHILE DISASSEMBLING TRANSFER GEARBOX (TGB), P/N 340-050-704-0, S/N VQ1169, FOR AN UNRELATED MAINTENANCE OPERATION, DETECTED
- [SDR 2023FA0000668](https://openairdocs.org/sdr/2023FA0000668.md): Bearing · galled · Oct 17, 2023
  > ACCESSORY GEAR [PN: 3103590-2] BEARING GALLED [PN: 3103585-1, SN: 13-151725-07567, TSN: 4,525.7, CSN: 5,527]. RESULTED IN FAILED SOAP REPORT DUE TO M50 PLATELET DETECTION.
- [SDR 2023FA0000277](https://openairdocs.org/sdr/2023FA0000277.md): Gearbox · incorrect · May 26, 2023 · Boeing 737*
  > THE ENGINE ABOVE WAS FITTED WITH ACCESSORY GEARBOX (AGB) P/N: 340-046-508-0, SN: WZ5025. DURING THE DISASSEMBLY, THE OPERATOR NOTICED THAT THE COVER WAS HELD IN PLACE BY 8 SCREWS P/N "AS3237-08" WHILE THE APPROVED DATA (ESM SM10 REV63 SECTION 726300) SPECIFI
- [SDR CALA2023010400022](https://openairdocs.org/sdr/CALA2023010400022.md): Nozzle · leaking · Jan 4, 2023 · N38955 · Boeing 7879
  > OIL QUANTITY INDICATION (ENGINE) SHOWS LOW FIM TASK 31-90-F8-03A-421B-A. RT ENGINE TEST NR 1 - DRY-MOTOR - LEAK TESTED IAW MM B787-A-G71-00-00-48A-364A-A. LEAK CONFIRMED AT FWD FACE ACCESSORY G/B OIL NOZZLE PACKING REF 72-64-00-03 ENG AGB ASSY-HOUSING, OIL
- [SDR PCSA202301040001](https://openairdocs.org/sdr/PCSA202301040001.md): Gearbox · faulted · Jan 3, 2023 · N496MM · Boeing 767300
  > ON FLIGHT 99 FROM ICN TO ANC, TEN MINUTES INTO THE FLIGHT, THE FLIGHT CREW REPORTED A HIGH ENGINE VIBRATION ON #2 ENGINE, FOLLOWED BY RELATED FIRE WARNING. THE CREW PROCEEDED TO DISCHARGE BOTH FIRE BOTTLES AND PERFORMED EMERGENCY PROCEDURES, RETURNING TO ICN
- [SDR 2022FA0000769](https://openairdocs.org/sdr/2022FA0000769.md): Bevel Gear · worn · Dec 19, 2022 · Airbus A330*
  > DURING MINOR EGB REPAIR, PREMATURE BEVEL GEARS WEAR IS IDENTIFIED (EXCESSIVE WEAR), AND GEARS REMOVED. THIS IS OUTSIDE ICA REQUIREMENTS AND STANDARD PRACTICES. WHEN INVESTIGATING ON PREVIOUS REPAIRED EGBS, 6 EGBS WHERE AFFECTED BY SIMILAR WEAR.
- [SDR 2022FA0000731](https://openairdocs.org/sdr/2022FA0000731.md): Line · leaking · Nov 22, 2022 · N865MA · Cessna 208B
  > SMOKE COMING OUT OF PILOTS SIDE VENT IN FLIGHT. UPON INVESTIGATION AFTER LANDING, IT WAS DISCOVERED THAT THE LINES GOING TO THE COMPRESSOR WERE LEAKING FREON.
- [SDR 2022F00447](https://openairdocs.org/sdr/2022F00447.md): Gearbox · contaminated · Nov 4, 2022
  > CUSTOMER REPORTED AOG ON SEPT 19, 2022 FOR MAGNETIC DEBRIS FOUND DURING REGULAR MCD INSPECTION. ENGINE WAS REMOVED AND AGB RETURNED TO SHOP. SHOP DID PERFORM THE LAST SHOP VISIT (AGB RELEASED ON JUNE 23, 2022 AS MODIFIED, 539.0 HOURS / 238 CYCLES SINCE THE R
- [SDR 9JLA2022100739009](https://openairdocs.org/sdr/9JLA2022100739009.md): Seal · leaking · Oct 5, 2022 · N910TX · Amd FALCON900B
  > DURING POST-FLIGHT CHECKS THE MAINTENANCE TECH DISCOVERED AN OIL LEAK FROM THE NO3 ENGINE. THE MAINTENANCE PROVIDER FOUND A LIP SEAL ON THE ACCESSORY GEARBOX FOR THE FUEL PUMP LEAKING. THE DEFECTIVE SEAL WAS REMOVED, AND A NEW CONDITION SEAL INSTALLED. LEAK CH
- [SDR 2022FA0000399](https://openairdocs.org/sdr/2022FA0000399.md): Gearbox · sheared · Jul 27, 2022 · N648KM · Diamon DA42
  > N648KM SUFFERED A GEARBOX SHAFT FAILURE ON ENGINE S/N 02-02-11284 @ 115 ENGINE HRS. THIS HAPPENED WHILST CONDUCTING POST MAINTENANCE GROUND RUNS FOLLOWING THE ANNUAL/100HR ENGINE INSPECTIONS IAW OEM REQUIREMENTS. A 100% POWER RUN WAS CARRIED OUT WITH THE ENGI
- [SDR 2022F00229](https://openairdocs.org/sdr/2022F00229.md): Engine · corroded · May 16, 2022 · N512QS · Cessna 680A
  > RH ENGINE AGB AFT COVER IS CORRODING.
- [SDR 2022F00228](https://openairdocs.org/sdr/2022F00228.md): Engine · corroded · May 16, 2022 · N512QS · Cessna 680A
  > LH ENGINE AGB AFT COVER IS CORRODING.
- [SDR 2021FA0000431](https://openairdocs.org/sdr/2021FA0000431.md): Gearbox · corroded · Dec 31, 2021 · N620QS · Cessna 680A
  > LH ENGINE AGB HAS CORROSION UNDER HYDRAULIC PUMP.
- [SDR 2021F00350](https://openairdocs.org/sdr/2021F00350.md): Engine · corroded · Dec 15, 2021 · N542QS · Cessna 680A
  > RH ENGINE AGB CORRODED IN MULTIPLE LOCATIONS.
- [SDR 2021FA0000395](https://openairdocs.org/sdr/2021FA0000395.md): Engine · corroded · Dec 13, 2021 · N536QS · Cessna 680A
  > RH ENGINE AGB REAR COVER HAS MULTIPLE AREAS OF CORROSION.
- [SDR 2022F00017](https://openairdocs.org/sdr/2022F00017.md): Engine · corroded · Dec 13, 2021 · N536QS · Cessna 680A
  > LH ENGINE AGB REAR COVER HAS MULTIPLE AREAS OF CORROSION.
- [SDR 2021FA0000394](https://openairdocs.org/sdr/2021FA0000394.md): Engine · corroded · Dec 13, 2021 · N536QS · Cessna 680A
  > RH ENGINE AGB COVER HAS MULTIPLE AREAS OF CORROSION.
- [SDR 2021FA0000393](https://openairdocs.org/sdr/2021FA0000393.md): Engine · corroded · Dec 13, 2021 · N536QS · Cessna 680A
  > LH ENGINE AGB REAR COVER HAS MULTIPLE AREAS OF CORROSION.
- [SDR 2021FA0000309](https://openairdocs.org/sdr/2021FA0000309.md): Gearbox · corroded · Nov 2, 2021 · N548QS · Cessna 680A
  > RH ENGINE GEARBOX AFT COVER CORRODED IN MULTIPLE LOCATIONS.
- [SDR 2021FA0000308](https://openairdocs.org/sdr/2021FA0000308.md): Gearbox · corroded · Nov 2, 2021 · N549QS · Cessna 680A
  > LH ENGINE GEARBOX AFT COVER CORRODED IN MULTIPLE LOCATIONS.
- [SDR 2021F00208](https://openairdocs.org/sdr/2021F00208.md): Cover · corroded · Oct 16, 2021 · N578QS · Cessna 680A
  > THE ACCESSORY GEARBOX REAR COVER IS CORRODING ON THE FLANGES AND AROUND BOLT HOLES. ACCOMPLISHED STEPS (1) THRU (4) OF THE REPAIR OF CORROSION OR PITTING ON ABG MOUNT PADS AND EXTERNAL SURFACES. INSPECT AGAIN AND REPEAT STEPS (1) THRU (4) AT EVERY AIRCRAFT MIN
- [SDR 2021F00207](https://openairdocs.org/sdr/2021F00207.md): Cover · corroded · Oct 16, 2021 · N578QS · Cessna 680A
  > THE ACCESSORY GEARBOX REAR COVER IS CORRODING ON THE FLANGES AND AROUND BOLT HOLES. ACCOMPLISHED STEPS (1) THRU (4) OF THE REPAIR OF CORROSION OR PITTING ON ABG MOUNT PADS AND EXTERNAL SURFACES. INSPECT AGAIN AND REPEAT STEPS (1) THRU (4) AT EVERY AIRCRAFT MIN
- [SDR 2021F00279](https://openairdocs.org/sdr/2021F00279.md): Mount · corroded · Oct 4, 2021 · N649QS · Cessna 680A
  > RH AGB AFT SIDE HAS CORROSION ON OIL LINE MOUNTING PAD JUST INBOARD OF HYDRAULIC FAN.
- [SDR 2021F00278](https://openairdocs.org/sdr/2021F00278.md): Mount · corroded · Oct 4, 2021 · N649QS · Cessna 680A
  > AFT SIDE OF LH AGB OUT BOARD SIDE HAS TWO OIL LINE MOUNTING PADS WITH CORROSION.
- [SDR 2021FA0000277](https://openairdocs.org/sdr/2021FA0000277.md): Cover · corroded · Oct 3, 2021 · N559QS · Cessna 680A
  > THE ACCESSORY GEARBOX REAR COVER IS CORRODING ON THE FLANGES AND AROUND BOLT HOLES. ACCOMPLISHED STEPS (1) THRU (4) OF THE REPAIR OF CORROSION OR PITTING ON ABG MOUNT PADS AND EXTERNAL SURFACES. INSPECT AGAIN AND REPEAT STEPS (1) THRU (4) AT EVERY AIRCRAFT MIN
- [SDR 2021F00253](https://openairdocs.org/sdr/2021F00253.md): Cover · corroded · Oct 3, 2021 · N559QS · Cessna 680A
  > THE ACCESSORY GEARBOX REAR COVER IS CORRODING ON THE FLANGES AND AROUND BOLT HOLES. ACCOMPLISHED STEPS (1) THRU (4) OF THE REPAIR OF CORROSION OR PITTING ON ABG MOUNT PADS AND EXTERNAL SURFACES. INSPECT AGAIN AND REPEAT STEPS (1) THRU (4) AT EVERY AIRCRAFT MIN
- [SDR 2021F00246](https://openairdocs.org/sdr/2021F00246.md): Gearbox · corroded · Aug 25, 2021 · N550QS · Cessna 680A
  > RH ENGINE GEARBOX AFT COVER CORRODED IN MULTIPLE LOCATIONS.
- [SDR 2021F00245](https://openairdocs.org/sdr/2021F00245.md): Gearbox · corroded · Aug 25, 2021 · N550QS · Cessna 680A
  > LH ENGINE GEARBOX AFT COVER CORRODED IN MULTIPLE LOCATIONS.
- [SDR 2021FA0000228](https://openairdocs.org/sdr/2021FA0000228.md): Gearbox · corroded · Aug 10, 2021 · N509QS · Cessna 680A
  > L/H ENGINE AGB AFT SIDE SHOWS SEVERAL AREAS OF CORROSION AND WAS REPAIRED IAW P&W MAINTENANCE MANUAL PART NO. 30B7302 72-60-01 B.

Next page: https://openairdocs.org/jasc/8300/reports.md?page=2

## 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 jasc_code = '8300'
ORDER BY difficulty_date DESC
```

This list as a web page: https://openairdocs.org/jasc/8300/reports

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