# Service difficulty reports: N478AS

A list on [N478AS](https://openairdocs.org/aircraft/N478AS.md).

Matched to this aircraft by N-number and event date, checked against the reported serial number, make and model. Newest first.

Page 1 of 4 · 188 reports

- [SDR ASAA2026032665136](https://openairdocs.org/sdr/ASAA2026032665136.md): Gust Lock · stuck · Mar 26, 2026 · N478AS · Boeing 737990ER · Passenger/Crew Doors
  > L1 DOOR GUST LOCK STUCK IN OPEN POSITION. GROUNDED - YES. L1 DOOR GUST LOCK OPS CHECK NORMAL PER AMM 52-11-00-200-801.
- [SDR ASAA2025060158385](https://openairdocs.org/sdr/ASAA2025060158385.md): Lens · broken · Jun 1, 2025 · N478AS · Boeing 737990ER · Emergency Lighting
  > SEAT 16F LOWER, DIRECTIONAL EMERGENCY EXIT LIGHT SIGN COVER BROKE OFF. GROUNDED - YES. REPLACED LENS COVER AS REQUIRED. EMERGENCY LIGHT OPERATES NORMALLY.
- [SDR ASAA2025030456424](https://openairdocs.org/sdr/ASAA2025030456424.md): Power Supply · inoperative · Mar 4, 2025 · N478AS · Boeing 737990ER · Emergency Lighting
  > EMERGENCY BATTERY PACK POWER SUPPLY M2816 NEEDS TO BE REPLACED. GROUNDED - YES. REMOVED AND REPLACED EMERGENCY BATTERY PACK POWER SUPPLY M2816, INSTALL TEST GOOD REF B737-900 AMM 33-51-06-960-806.
- [SDR ASAA2025030456423](https://openairdocs.org/sdr/ASAA2025030456423.md): Power Supply · inoperative · Mar 4, 2025 · N478AS · Boeing 737990ER · Emergency Lighting
  > EMERGENCY BATTERY PACK POWER SUPPLY M1676 NEEDS TO BE REPLACED. GROUNDED - YES. REMOVED AND REPLACED EMERGENCY BATTERY PACK POWER SUPPLY M1676, INSTALL TEST GOOD REF B737-900 AMM 33-51-06-960-806.
- [SDR ASAA2025030456422](https://openairdocs.org/sdr/ASAA2025030456422.md): Power Supply · inoperative · Mar 4, 2025 · N478AS · Boeing 737990ER · Emergency Lighting
  > EMERGENCY BATTERY PACK POWER SUPPLY M1694 NEEDS TO BE REPLACED. GROUNDED - YES. REMOVED AND REPLACED EMERGENCY BATTERY PACK POWER SUPPLY M1694, INSTALL TEST GOOD REF B737-900 AMM 33-51-06-960-806.
- [SDR ASAA2025030746421](https://openairdocs.org/sdr/ASAA2025030746421.md): Power Supply · inoperative · Mar 4, 2025 · N478AS · Boeing 737990ER · Emergency Lighting
  > EMERGENCY BATTERY PACK POWER SUPPLY M1672 NEEDS TO BE REPLACED. GROUNDED - YES. REMOVED AND REPLACED EMERGENCY BATTERY PACK POWER SUPPLY M1672, INSTALL TEST GOOD REF B737-900 AMM 33-51-06-960-806.
- [SDR ASAA2025030746420](https://openairdocs.org/sdr/ASAA2025030746420.md): Power Supply · inoperative · Mar 4, 2025 · N478AS · Boeing 737990ER · Emergency Lighting
  > EMERGENCY BATTERY PACK POWER SUPPLY M2627 NEEDS TO BE REPLACED. GROUNDED - YES. REMOVED AND REPLACED EMERGENCY BATTERY PACK POWER SUPPLY M2627, INSTALL TEST GOOD REF B737-900 AMM 33-51-06-960-806.
- [SDR ASAA2025022456350](https://openairdocs.org/sdr/ASAA2025022456350.md): Floor Panel · cracked · Feb 24, 2025 · N478AS · Boeing 737990ER · Fuselage Floor Panel
  > FWD WET AREA FLOOP PANEL 141A5810-729 CORNER TAB IS BROKEN & LOWER SURFACE IS DAMAGED. GROUNDED - YES. REPAIRED BROKEN CORNER TAB USING A PERMANENT WET LAY UP REPAIR. REPAIRED DAMAGED LOWER SURFACE USING A PERMANENT REPAIR WITH POTTING COMPOUND AND WET LAY UP
- [SDR ASAA2025021856302](https://openairdocs.org/sdr/ASAA2025021856302.md): Floor Panel · delaminated · Feb 18, 2025 · N478AS · Boeing 737990ER · Fuselage Floor Panel
  > FWD WET AREA FLOOR PANEL 141A5810-303 HAS PEELING FIBERS & CORRODED INSERTS. GROUNDED - YES. COMPLETED WET LAY UP REPAIR AND REMOVED/REPLACED INSERTS ON FWD WET AREA FLOOR PANEL 141A5810-303 IAW B737-900ER SRM 53-10-50-2R-0, 53-00-50-2R-0.
- [SDR ASAA2024121854709](https://openairdocs.org/sdr/ASAA2024121854709.md): Glowstrip · deteriorated · Dec 18, 2024 · N478AS · Boeing 737990ER · Emergency Equipment
  > FA REPORTS THAT APPROX 6 INCHES OF EMERGENCY LIGHTING FLOOR STRIP AT THE AFT RIGHT SIDE B4 LAV E IS DAMAGED WILL NOT GLOW. GROUNDED - YES. REMOVED & REPLACED AFT RH 6 FT SECTION AT ROW 34 REF AMM 33-51-15.
- [SDR ASAA2024081651918](https://openairdocs.org/sdr/ASAA2024081651918.md): Battery Pack · inoperative · Aug 16, 2024 · N478AS · Boeing 737990ER · Emergency Lighting
  > DURING EMERGENCY LIGHT OPS TEST FOUND A EMERGENCY LIGHT BATTERY PACK INOP. GROUNDED - YES. REPLACED EMERGENCY LIGHT BATTERY PACK IAW AMM 33-51-06. OPS TEST GOOD.
- [SDR ASAA2024040548892](https://openairdocs.org/sdr/ASAA2024040548892.md): Cover · detached · Apr 5, 2024 · N478AS · Boeing 737990ER · Emergency Lighting
  > CEILING EXIT SIGN COVER CAME OFF. GROUNDED - YES. REINSTALLED EMERGENCY EXIT SIGN COVER & OK FOR SVC REF AMM 33-51-01.
- [SDR ASAA2024013197594](https://openairdocs.org/sdr/ASAA2024013197594.md): Sign · broken · Jan 29, 2024 · N478AS · Boeing 737990ER · Emergency Lighting
  > FA REPORTS BROKEN EXIT SIGN AT MID-CABIN. GROUNDED - YES. CHECKED ALL EMERGENCY EXIT SIGNS AT AND AROUND MID CABIN, AS WELL AS THROUGHOUT A/C. ALL SIGNS FOUND SECURE AND NO DEFECTS NOTED. OPS CHECK OF ALL SIGNS GOOD.
- [SDR ASAA2023110546020](https://openairdocs.org/sdr/ASAA2023110546020.md): Unknown · unknown · Nov 5, 2023 · N478AS · Boeing 737990ER · HF Communications System
  > DURING PRE-FLIGHT HF-2 "FAIL-FAIL ANNUNCIATED ON ACP. GROUNDED - YES. PERFORMED RESET AND OPS TEST PER AMM 23-11-21-860-006, OK FOR SERVICE.
- [SDR ASAA2023102245800](https://openairdocs.org/sdr/ASAA2023102245800.md): Unknown · unknown · Oct 22, 2023 · N478AS · Boeing 737990ER · DC Generating System
  > ELEC LIGHT ON GROUND. GROUNDED - YES. CARRIED OUT FIM TASK 24-31 TASK 801. PERFORMED BITE TEST PROC, FAULT CLEARED. NO OTHER MAINT PROC REQUIRED.
- [SDR ASAA2023090444947](https://openairdocs.org/sdr/ASAA2023090444947.md): Fmc · faulty · Sep 4, 2023 · N478AS · Boeing 737990ER · Flight Management Computing Hardware System
  > LEFT FMC INTERMITTENTLY FAILS AND RESTORES ITSELF FROM LANDING UNTIL PARKED AT THE GATE. LASTED APPROXIMATELY 20 MINUTES. AFTER SHUTDOWN LEFT FMC FAILED AND WOULD NOT RESTORE ITSELF. GROUNDED - YES. REMOVED AND REPLACED L/H FMC, PULLED, COLLARED, AND RESET 2 E
- [SDR ASAA2023082444753](https://openairdocs.org/sdr/ASAA2023082444753.md): Heater · leaking · Aug 24, 2023 · N478AS · Boeing 737990ER · Engine Fuel Distribution
  > WHILE PERFORMING IDLE POWER LEAK CHECK ON #1 ENG FOUND FULE LEAK AT TOP BACK SIDE OF THE FUEL HEATER SERVO. GROUNDED - YES. REMOVED & REPLACED #1 ENG SERVO FUEL HEATER REF MM 73-11-07. LEAK CHECKED GOOD.
- [SDR ASAA2023082044669](https://openairdocs.org/sdr/ASAA2023082044669.md): Unknown · unknown · Aug 20, 2023 · N478AS · Boeing 737990ER · Cabin Cooling System
  > RIGHT PACK LIGHT ILLUMINATES ON RECALL, EXTINGUISHES WHEN RESET. GROUNDED - YES. INITIAL EVAL, RH PACK LT ILLUMINATED ON P5 OVERHEAD WITH MASTER RECALL. PERFORMED PZTC BITE IAW FIM 21-62 TASK 801. LH PZTC, NO FAULTS. RH PZTC HAD TCV ON BIT, CLEARED GREEN ON VE
- [SDR ASAA2023081844667](https://openairdocs.org/sdr/ASAA2023081844667.md): Unknown · unknown · Aug 18, 2023 · N478AS · Boeing 737990ER · Cabin Temperature Control System
  > ON RECALL CONT CABIN ZONE TEMP LIGHT ILLUMINATES EXTINGUISHED ON MASTER RECALL RESET. GROUNDED - YES. ACCOMPLISHED PZTC BITE REF MM 21-61-00-700-806-002. LAST FLT FAULTED THE FLT DECK TRIM VALVE. FAULT RESET UPON VERIFICATION. GROUND VERIFICATION SUCCESSFUL. T
- [SDR ASAA2023080744485](https://openairdocs.org/sdr/ASAA2023080744485.md): Windshield · damaged · Aug 7, 2023 · N478AS · Boeing 737990ER · Flight Compartment Windows
  > R1 WINDSHIELD HAS EVIDENCE OF ARCING ON UPPER RIGHT CORNER NEAR SOLDER JOINT. GROUNDED - YES. REPLACED R1 WINDOW IAW AMM 56-11-11-4020-801 STEP 3.H(1-14) JM 53114 MBG 43347COMPLETED INSTALLATION OF R1 WINDOW REF AMM 56-11-11-400-801 OPS CHK GOOD.
- [SDR ASAA2023072244182](https://openairdocs.org/sdr/ASAA2023072244182.md): Unknown · unknown · Jul 22, 2023 · N478AS · Boeing 737990ER · Emergency Lighting
  > EMERGENCY LIGHT AFT OF L2 DOOR INOP. GROUNDED - YES. RELAMPED AS REQUIRED. OPS TEST GOOD.
- [SDR ASAA2023071043977](https://openairdocs.org/sdr/ASAA2023071043977.md): Unknown · unknown · Jul 10, 2023 · N478AS · Boeing 737990ER · Airborne Auxiliary Power Unit (APU) System
  > APU MAINT LIGHT ILLUMINATES INTERMITENTLY. GROUNDED - YES. PERFORMED APU BITE TEST PER FIM 49-60 TASK 801 NO FAULT FOUND APU MAINT LIGHT IS OFF SEAMC DAN NOTIFIED.
- [SDR ASAA2023062243666](https://openairdocs.org/sdr/ASAA2023062243666.md): Unknown · unknown · Jun 22, 2023 · N478AS · Boeing 737990ER · Cabin Temperature Control System
  > CONT CAB MASTER CAUTION, RESETS ON RESET. GROUNDED - YES. PERFORMED PACK/ZONE TEMPERATURE CONTROLLER BITE TEST REF AMM TASK 21-61-00-700-806-002. TEST PASSED.
- [SDR ASAA2023060943530](https://openairdocs.org/sdr/ASAA2023060943530.md): Power Strip · faulty · Jun 9, 2023 · N478AS · Boeing 737990ER · Emergency Lighting
  > FA REPORTS EXIT S1GNS/LIGHTS ABOVE L2,R2 & AFT GALLEY WHERE INTERMITTENTLY FLASHING DURING BOARDING. GROUNDED - YES. VERIFIED DEFECT EMERGENCY LTS RANDOMLY ILLUMINATE ON AND OFF AR L2, R2 AFT GALLEY AND ROW 31ABC. REMOVED AND REPLACED PWR SUPPLY 1673 REF B737-
- [SDR ASAA2023060843529](https://openairdocs.org/sdr/ASAA2023060843529.md): Unknown · unknown · Jun 8, 2023 · N478AS · Boeing 737990ER · Emergency Lighting
  > FLT ATT REPORTS EXIT SIGNS/LIGHTS ABOVE L2,R2, & AFT GALLEY CEILING WERE INTERMITTENTLY FLASHING DURING BOARDING, FLIGHT AND AFTER ARRIVAL. GROUNDED - YES. ACCOMPLISHED B737-900 AMM 33-51-00-720-801 EMERGENCY LIGHTS OPERATIONAL CHECK PERFORMED FOUND OK. AIRCRA
- [SDR ASAA2023041742914](https://openairdocs.org/sdr/ASAA2023041742914.md): Unknown · unknown · Apr 17, 2023 · N478AS · Boeing 737990ER · Autopilot System
  > SPEED TRIM LIGHT ILLUMINATED ON MASTER CAUTION RECALL AFTER FCF TEST. ABLE TO RESET WITH MASTER CAUTION RESET. GROUNDED - YES. PERFORMED B737-900 FIM 22-11 TASK 850, FOUND FAULT MESSAGE 22-11182 ON LEG 1 OF CHANNEL "A". RAN LRU TRUE ON FAULT PAGE, TEST PASSED.
- [SDR ASAA2023041242847](https://openairdocs.org/sdr/ASAA2023041242847.md): Power Supply · inoperative · Apr 12, 2023 · N478AS · Boeing 737990ER · Emergency Lighting
  > EMERGENCY LIGHTS COMMON TO POWER SUPPLY M1675 ARE INOP. GROUNDED - YES. REMOVED AND REPLACED EMERGENCY LIGHT POWER SUPPLY M1675 & INSTALLATION TEST GOOD IAW B737-900 AMM 33-51-06 OP CHECK GOODPO 1057542-1.
- [SDR ASAA2023033042834](https://openairdocs.org/sdr/ASAA2023033042834.md): Web · punctured · Mar 30, 2023 · N478AS · Boeing 737990ER · Fuselage Main, Structure
  > E&E ACCESS BAY: PUNCTURE ON LH SIDE OF E&E ACCESS DOOR FRAME ABOVE LATCH REVEIVER. GROUNDED - YES. REMOVED DAMAGED WEB PER B737-900 SRM 51-40-02LOCATED MAT ID AND FABBED WEB PER B737-900 SRM 51-40-05, DWG 141A8512 REV E AND GPM 05-00-85.APPLIED PROTECTIVE TREA
- [SDR ASAA2023030842265](https://openairdocs.org/sdr/ASAA2023030842265.md): Unknown · unknown · Mar 8, 2023 · N478AS · Boeing 737990ER · Cabin Pressure Control System
  > AFTER LANDING PRESSURE CONTROLLER DISPLAYED AUTO FAIL + ALTN. SELECTED ALTN WITH PRESSURIZATION MODE SELECTOR AND AUTO FAIL EXTINGUISHED. GROUNDED - YES. CPC 1 SET FAULT 011: OFV LRU FAIL. CPC2 INDICATES NO FAILURES. GVI ACCOMPLISHED OF OFV OBSERVING NO OBSTRU
- [SDR ASAA2023030442183](https://openairdocs.org/sdr/ASAA2023030442183.md): Battery Pack · intermittent · Mar 4, 2023 · N478AS · Boeing 737990ER · Emergency Lighting
  > EMERGENCY EXIT SIGNS LOCATED AT THE AFT LOWERED CEILING AND ABOVE THE AFT AFT ENTRY AND AFT SERVICE DOOR WITH EMERGENCY EXIT LIGHT SWITCH IN ARMED POSITION, CYCLE AND OFF. GROUNDED - YES. REPLACED EMERGENCY LIGHT BATTERY ON PACK M1673, OPS CHECK GOOD. REF B737
- [SDR ASAA2023021841982](https://openairdocs.org/sdr/ASAA2023021841982.md): Unknown · unknown · Feb 18, 2023 · N478AS · Boeing 737990ER · Autopilot System
  > ON APPROACH FO'S FLIGHT DIRECTOR LATERAL DEVIATION BAR DISAPPEARED AFTER LOC CAPTURE, THEN AFTER G/S CAPTURE LOST VERTICAL FLIGHT DIRECTOR BAR AS WELL AND A/P DISENGAGED. HAD BOTH A/P'S ENGAGED FOR CIII/AUTOLAND APPROACH AT THE TIME. GROUNDED - YES. FOUND FAUL
- [SDR ASAA2023020741872](https://openairdocs.org/sdr/ASAA2023020741872.md): Transceiver · failed · Feb 7, 2023 · N478AS · Boeing 737990ER · HF Communications System
  > WHEN SELECTED HF #1 SHOWS FAIL ON RADIO TUNING PANELS. GROUNDED - YES. VERIFIED, CYCLED HF#1 C/B, FREQS APPEARS WITH NO AUDIO SIDE TONE THEN CHANGE BACK TO FAIL. REMOVED & REPLACED HF-1 TRANSCEIVER REF B737-900 AMM 23-11-21.
- [SDR ASAA2023020241776](https://openairdocs.org/sdr/ASAA2023020241776.md): Not Reported · not reported · Feb 2, 2023 · N478AS · Boeing 737990ER · Emergency Lighting
  > DURING T/O ROLL AND AGAIN CLIMBING THRU FL250 AFT GALLEY EMERGENCY LIGHTS WENT ON AND EXTINGUISHED AFTER 1MIN. AFT GALLEY EMERG LT. SW WORKS AS ADVERTISED. GROUNDED - YES. PERFORMED OPS TEST OF EMERGENCY LIGHTS REF B737-900 AMM 33-51-00-710-801. OPS CHECKS GOO
- [SDR ASAA2023012841724](https://openairdocs.org/sdr/ASAA2023012841724.md): Seal · leaking · Jan 28, 2023 · N478AS · Boeing 737990ER · Turbine Engine Accessory Drive
  > #1 ENGINE OIL TREND DATA SHOWS OIL CONSUMPTION TO GREATER THAN EXPECTED. ENGINE POWER RUN REQUIRED. GROUNDED - YES. BAGGED APPLICABLE OIL DRAIN LINES FOR POWER RUN. DURING PART POWER RUN, DISCOVERED LARGE AMOUNT OF OIL COMING OUT OF N2 DRIVE PAD DRAIN. REMOVED
- [SDR ASAA2023011741554](https://openairdocs.org/sdr/ASAA2023011741554.md): Bleed Valve · faulted · Jan 17, 2023 · N478AS · Boeing 737990ER · Compressor Bleed Valve
  > WHILE WORKING T/C N84360001, FOUND #1 ENG BLEED AIR REGULATOR DEFECTIVE. FAILED DURING SUBTASK 836-201. OVER PRESSURE SWITCH TEST. GROUNDED - YES. REMOVED AND REPLACED THE #1 ENG BLEED AIR REGULATOR REF B737-900 AMM 36-11-03. LEAK CHECK OF THE #1 ENG BLEED AIR
- [SDR ASAA2023011741553](https://openairdocs.org/sdr/ASAA2023011741553.md): Bleed Valve · faulted · Jan 17, 2023 · N478AS · Boeing 737990ER · Compressor Bleed Valve
  > WHILE WORKING T/C N8436001 FOUND #1 ENG HIGH STAGE REGULATOR DEFECTIVE FAILED DURING SUBTASK 839-415. REVERSE FLOW TEST. GROUNDED - YES. REMOVED AND REPLACED THE #1 ENG HIGH STAGE REGULATOR REF B737-900 AMM 36-11-07. LEAK CHECK GOOD PER AMM 36-11-07 AND 36-11-
- [SDR ASAA2023011741550](https://openairdocs.org/sdr/ASAA2023011741550.md): Solenoid · inoperative · Jan 17, 2023 · N478AS · Boeing 737990ER · Engine Anti-Icing System
  > #2 ENG GROUND WING TAI SOLENOID VALVE INOP. GROUNDED - YES. REPLACED SOLENOID VALVE, OPS/LEAK CHECK OK. REF. B737-900 AMM 30-11-12-400-801.
- [SDR ASAA2022091439944](https://openairdocs.org/sdr/ASAA2022091439944.md): Control Panel · inoperative · Sep 14, 2022 · N478AS · Boeing 737990ER · Autopilot System
  > AUTOTHROTTLE DISENGAGE LIGHT INOP. GROUNDED - YES. REMOVED AND REPLACED MCP REF B737-900 AMM 22-11-34.
- [SDR ASAA2022091439943](https://openairdocs.org/sdr/ASAA2022091439943.md): Control Panel · inoperative · Sep 14, 2022 · N478AS · Boeing 737990ER · Autopilot System
  > AUTOPILOT ORAL WARNING INOP. GROUNDED - YES. REMOVED AND REPLACED MCP REF B737-900 AMM 22-11-34.
- [SDR ASAA2022090139755](https://openairdocs.org/sdr/ASAA2022090139755.md): Unknown · failed · Sep 1, 2022 · N478AS · Boeing 737 · Autopilot System
  > AURAL WAILER DOES NOT SOUND WHEN EITHER AUTOPILOT IS DISCONNECTED. GROUNDED - YES. REF B737-900 AMM 22-11-41, REMOVED/REPLACED F/O'S YOKE A/P DISENGAGE SWITCH.
- [SDR ASAA2022081739533](https://openairdocs.org/sdr/ASAA2022081739533.md): Control Valve · warning light · Aug 17, 2022 · N478AS · Boeing 737990ER · Cabin Cooling System
  > RT PACK LIGHT ON. GROUNDED - YES. BITE SHOWS #2 CONTROLLER HAS TCV FAULT. RT PACK LIGHT ON STEARD WILL NOT RESET. TURNED PACK OFF AND LET COOL. TRIP RESET GOOD. OPS NORMAL REF. B737-900 AMM 21-62-00.
- [SDR ASAA2022060638579](https://openairdocs.org/sdr/ASAA2022060638579.md): Plug · detached · Jun 6, 2022 · N478AS · Boeing 737990ER · Pneumatic Distribution System
  > AFTER PERFORMING A NO BLEED TAKEOFF AND WHILE REESTABLISHING NORMAL CONFIGURATION, THE LEFT DUCT WAS PRESSURIZED REGARDLESS OF SWITCH POSITIONS, - ISOLATION VALVE CLOSED, APU AND #1 BLEED OFF, LEFT DUCT STILL PRESSURIZED. NEEDLE NOT STUCK. WE DID SEE SLIGHT MO
- [SDR ASAA2022060438553](https://openairdocs.org/sdr/ASAA2022060438553.md): Transceiver · failed · Jun 4, 2022 · N478AS · Boeing 737990ER · HF Communications System
  > HF RADIO 1 DISPLAYING FAIL. GROUNDED - YES. REMOVED AND REPLACED HF TRANSCEIVER HF1. OPS CHECKED GOOD. REF B737-900 AMM TASK 23-11-21-400-801. REF B737-900 FIM 23-11 TASK 803.
- [SDR ASAA2022060338546](https://openairdocs.org/sdr/ASAA2022060338546.md): Brake Assy · failed · Jun 3, 2022 · N478AS · Boeing 737990ER · Engine Controls
  > REPORTS OF #2 ENGINE FAIL MESSAGE AT ENGINE SHUTDOWN. GROUNDED - YES. REMOVED AND REPLACED #2 ENGINE START BRAKE ASSEMBLY REF B737-900 AMM 76-11-10/401. OPERATIONAL CHECK GOOD REF AMM 76-11-10-420-801-F00 STEP H. ETOPS GROUND VERIFICATION SUCCESSFUL.
- [SDR ASAA2022052638508](https://openairdocs.org/sdr/ASAA2022052638508.md): Relay · faulty · May 26, 2022 · N478AS · Boeing 737990ER · Engine Fuel and Control
  > AT GATE DURING ENGINE SHUTDOWN WITH START LEVERS CUTOFF THE #2 ENGINE SHOWED "ENGINE FAILURE" MOMENTARILY. GROUNDED - YES. ACCOMP B737-900 FIM 73-05 TASK 805, STEPS A(3) AND STEPS (13), (17) DEU INPUT MONITORING TEST. ACCOMPLISHED VOLTAGE/GRND/CONTINUITY CHECK
- [SDR ASAA2022052438436](https://openairdocs.org/sdr/ASAA2022052438436.md): Chip Detector · plugged · May 24, 2022 · N478AS · Boeing 737990ER · Engine Cranking
  > DURING INSPECTION OF #2 ENG STARTER CHIP DETECTOR, FOUND UNACCEPTABLE AMOUNT OF MAGNETIC PARTICLES. GROUNDED - YES. REMOVED AND REPLACED #2 ENG STARTER REF B737-900 AMM 80-11-01. OPS CHECKS AND LEAK CHECK GOOD.
- [SDR ASAA2022050438207](https://openairdocs.org/sdr/ASAA2022050438207.md): Circuit Breaker · failed · May 4, 2022 · N478AS · Boeing 737990ER · Windshield/Door Rain/Ice Removal
  > WHILE CRUISING AT FL360 THE LEFT FRONT WINDOW OVERHEAT LIGHT ILLUMINATED. TURNED L FWD WINDOW HEAT SWITCH OFF FOR 5 MINUTES AND THEN TURNED IT BACK ON PER QRH PROCEDURE AND THE OVERHEAT LIGHT ILLUMINATED IMMEDIATELY. GROUNDED - YES. FOUND LEFT FRONT WINDOW HEA
- [SDR ASAA2022031437703](https://openairdocs.org/sdr/ASAA2022031437703.md): Modulating Valve · faulty · Mar 14, 2022 · N478AS · Boeing 737990ER · Cabin Temperature Control System
  > CONT CAB ZONE TEMP LIGHT ON RECALL. GROUNDED - YES. PERFORMED BITE CHECK OF PACK/ZONE TEMP CONTROLLER REF B737-900 AMM 21-61-00-700-806-002, FOUND FAULT FLT DECK TRIM VALVE. REMOVED AND REPLACED CONT TRIM VALVE REF AMM 21-61-21-000-801 AND 21-61-21-400-801, OP
- [SDR ASAA2022022337538](https://openairdocs.org/sdr/ASAA2022022337538.md): Transceiver · inoperative · Feb 23, 2022 · N478AS · Boeing 737990ER · HF Communications System
  > HF 2 SHOWING "FAIL" ON COM PANEL. GROUNDED - YES. REMOVED AND REPLACED #2 HF XCEIVER REF B737-900 AMM 23-11-21. OPS CHECK NORMAL PER SAME, NO FAULTS NOTED AT THIS TIME.
- [SDR ASAA2021112536771](https://openairdocs.org/sdr/ASAA2021112536771.md): Modulating Valve · faulted · Nov 25, 2021 · N478AS · Boeing 737990ER · Cabin Cooling System
  > LEFT PACK LIGHT ILLUMINATES ON RECALL EXTINGUISHED ON MASTER RESET. GROUNDED - YES. REMOVED AND REPLACED LH TEMPERATURE CONTROL VALVE IAW AMM 21-51-10-000-801 AND AMM 21-51-10-400-801, ETOPS GROUND FUNCTIONAL CHECK GOOD IAW AMM 21-61-00-700-806-002, CLEARS MEL

Next page: https://openairdocs.org/aircraft/N478AS/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 n_number = 'N478AS' AND registry_match = 'registration'
ORDER BY difficulty_date DESC
```

This list as a web page: https://openairdocs.org/aircraft/N478AS/reports

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