# Service difficulty reports: N491AS

A list on [N491AS](https://openairdocs.org/aircraft/N491AS.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 · 192 reports

- [SDR ASAA2025040957615](https://openairdocs.org/sdr/ASAA2025040957615.md): Transition Panel · corroded · Apr 9, 2025 · N491AS · Boeing 737990ER · Fuselage Miscellaneous Structure
  > AFT CARGO R/H TRANSITION STA 727+4-727I+8 CORRODED IN MULTIPLE AREA. GROUNDED - YES. REMOVED DAMAGE, FOUND TO BE OUT OF LIMTS, REPAIRED IAW B737-900 SRM 53-00-53-2R-6W= 1" O=.040 R=.034 L= 1" D=.006.
- [SDR ASAA2025040957614](https://openairdocs.org/sdr/ASAA2025040957614.md): Transition Panel · corroded · Apr 9, 2025 · N491AS · Boeing 737990ER · Fuselage Miscellaneous Structure
  > AFT CARGO R/H TRANSITION STA 727I+8-767 CORRODED IN MULTIPLE AREAS. GROUNDED - YES. REMOVED DAMAGE, FOUND TO BE OUT OF LIMITS, REPAIRED IAW B737-900 SRM 53-00-53-2R-6W= 1" O=.040 R=.030 L= 1" D=.010.
- [SDR ASAA2025040957613](https://openairdocs.org/sdr/ASAA2025040957613.md): Web · corroded · Apr 9, 2025 · N491AS · Boeing 737990ER · Fuselage Miscellaneous Structure
  > AFT CARGO DOOR SILL WEB CORRODED. GROUNDED - YES. REMOVED DAMAGE FOUND TO BE OUT OF LIMITS, REMVOED AND REPLACED SILL WEB AFT CARGO DOOR IAW B737-900 SRM 51-40-02-0G-0W= 4" O=.045 R=.038 L= 1" D=.007.
- [SDR ASAA2025040957612](https://openairdocs.org/sdr/ASAA2025040957612.md): Shield · corroded · Apr 9, 2025 · N491AS · Boeing 737990ER · Fuselage Miscellaneous Structure
  > AFT CARGO SHIELD FWD OF DOOR CUTOUT CORRODED. GROUNDED - YES. REMOVED DAMAGE ON SHIELD. MAX MAT LOSS 0.007" FOUND TO BE OUT LIMITS AND REMOVED AND INSTALLED NEW SHIELD ON AFT CARGO COMPT IAW B737-900 SRM 53-60-15-1A-1 AND SRM 52-40-02-06-0W= 2" O=.050 R=.043
- [SDR ASAA2025040957611](https://openairdocs.org/sdr/ASAA2025040957611.md): Splice · corroded · Apr 9, 2025 · N491AS · Boeing 737990ER · Fuselage Floor Panel
  > FLOORBOARD SPLICE CORROED STA 767. GROUNDED - YES. FABRICATED REPLACEMENT FLOOR SPLICE TEE. AT STA 767 IAW B737-900 SRM 53-60-53-01-2, SRM 51-40-05-0G-0. W= 1" O=.070 R=.000 L= 1" D=.070
- [SDR ASAA2025040957610](https://openairdocs.org/sdr/ASAA2025040957610.md): Transition Panel · corroded · Apr 9, 2025 · N491AS · Boeing 737990ER · Fuselage Miscellaneous Structure
  > AFT CARGO L/H TRANSITION STA 727B-727I+8 CORRODED IN MULTIPLE AREAS. GROUNDED - YES. EVALUATION AT DAMAGE, 100% MAT LOSS, FOUND TO BE OUT OF LIMITS REPAIRED IAW B737-900 SRM 53-00-53-2R-RW = 1" O=.040 R= 0 L= 1" D=.040.
- [SDR ASAA2025040957609](https://openairdocs.org/sdr/ASAA2025040957609.md): Transition Panel · corroded · Apr 9, 2025 · N491AS · Boeing 737990ER · Fuselage Miscellaneous Structure
  > AFT CARGO L/H TRANSITION STA 727I+8-847 HAS MULTIPLE AREAS OF CORROSION. GROUNDED - YES. EVALUATED DAMAGE, 100% MAT LOSS FOUND TO BE OUT OF LIMITS REPAIRED IAW B737-900 SRM 53-00-53-2R-5W=1" O=.040 R= 0 L= 1" D=.040.
- [SDR ASAA2025040857616](https://openairdocs.org/sdr/ASAA2025040857616.md): Transition Panel · corroded · Apr 8, 2025 · N491AS · Boeing 737990ER · Fuselage Miscellaneous Structure
  > FWD CARGO TRANSITION AT RBL-21 CORRODED MULTIPLE AREAS BETWEEN STA 500A TO STA 500H+10. GROUNDED - YES. REMOVED CORROSION FOUND TO BE OUT OF LIMITS, REMVOED AND REPLACED FWD CARGO TRANSITION AT R-BL21 STA 500A TO 500H+10 IAW B737-900 SRM 53-00-53-2R-5W= 3" O=
- [SDR ASAA2024051749704](https://openairdocs.org/sdr/ASAA2024051749704.md): Battery Pack · no test · May 17, 2024 · N491AS · Boeing 737990ER · Emergency Lighting
  > PER T/C 78233001 EMER BAT PACK CAPACITY FUNCTIONAL CHECK, FOUND SOME BATTERY PACK FAIL THE TIME TEST AS FOLLOW: R2 AND L2 DOORS INSIDE AND OUTSIDE. R1 AND L1 DOORS INSIDE AND OUTSIDE. AFT GALLEY EXIT SIGN. GROUNDED - YES. REMOVED AND REPLACED THE FOLLOWING EME
- [SDR ASAA2024050449433](https://openairdocs.org/sdr/ASAA2024050449433.md): Light · detached · May 4, 2024 · N491AS · Boeing 737990ER · Emergency Lighting
  > GALLEY FLOOR TRIPPING HAZARD. GROUNDED - YES. TRIPPING HAZARD FOUND TO BE FIRST 6" OF FLOOR PROXIMITY LIGHT PHOTO. STRIP. REMOVED & REPLACED A/C LEFT FIRST PHOTO PROXIMITY LIGHT STRIP REF AMM 33-51-15.
- [SDR ASAA2024022748107](https://openairdocs.org/sdr/ASAA2024022748107.md): Light · intermittent · Feb 27, 2024 · N491AS · Boeing 737990ER · Emergency Lighting
  > FORWARD AND AFT GALLEY EMERGENCY EXIT AISLE LIGHTS ILLUMINATED WITH EMER EXIT LIGHTS SWITCH IN BOTH ARMED AND OFF MODES. GROUNDED - YES. PERFORMED FIM 33-50 TASK 801 FOUNF TO BE AN INTERMITTENT FAULT.
- [SDR ASAA2023110746067](https://openairdocs.org/sdr/ASAA2023110746067.md): Igniter · failed · Nov 7, 2023 · N491AS · Boeing 737990ER · Spark Plug/Igniter
  > #1 ENG R IGNITION FAILED TO LIGHT OFF. GROUNDED - YES. (RESOLVED ON W/O: 1976943 TASKCARD: N/R-00001) REPLACED ENGINE 1 RIGHT HAND IGNITER PLUG PER AMM 74-21-02. PERFORMED AMM TASK 74-00-00-040-802-FOO MMEL 74-1 RIGHT IGNITION SYSTEM TO RESTORE CONFIGURATION.
- [SDR ASAA2023102745879](https://openairdocs.org/sdr/ASAA2023102745879.md): Unknown · unknown · Oct 27, 2023 · N491AS · Boeing 737990ER · Cabin Cooling System
  > R PACK LIGHT ILLUMINATES ON MASTER CAUTION RECALL, IT GOES OUT WHEN MASTER CAUTION PUSHED. GROUNDED - YES. ON DEFERRAL.
- [SDR ASAA2023101745719](https://openairdocs.org/sdr/ASAA2023101745719.md): Unknown · unknown · Oct 17, 2023 · N491AS · Boeing 737990ER · Cabin Temperature Control System
  > CONT CAB ZONE TEMP ILLUMINATED ON RECALL. GROUNDED - YES. RELEASED PER MEL 21-21G. FLIGHT DECK PRIMARY TEMP CONTROL INOP. AUTH BY SEAMC MIKE 1659Z.PERFORMED CABIN TEMP CTRL BITE CHECK. REF FIM 21-61 TASK 801. NO FAULTS NOTED. CONT CABIN ZONE TEMP LIGHT EXTINGU
- [SDR ASAA2023101645689](https://openairdocs.org/sdr/ASAA2023101645689.md): Unknown · unknown · Oct 16, 2023 · N491AS · Boeing 737990ER · Flight Management Computing Hardware System
  > DURING CRUISE VTK FLAG APPEARED MOMENTARILY ON FIRST OFFICER NAV DISPLAY DISAPPEARED AFTER 20 SECONDS. NO OTHER LOSS OF LNAV & VNAV OR FMC. GROUNDED - YES. PERFORMED B737-9 FIM 34-61 TASK 836 & RT FMC OPS NORMAL.
- [SDR ASAA2023101545634](https://openairdocs.org/sdr/ASAA2023101545634.md): Fmc · faulty · Oct 15, 2023 · N491AS · Boeing 737990ER · Autopilot System
  > AT ABOUT 200 AGL DURING AUTOLAND, WHEN STABILIZER TRIMMED NOSE UP, AN APPROACH WARNING ANNUNCIATED ON THE HUD, THE AUTOPILOT DISENGAGED & THE AIRCRAFT BEGAN LEVELING OFF AT ABOUT 100 AGL RUNWAY 16R. GROUNDED - YES. (RESOLVED ON W/O: 1972063 TASKCARD: N/R-00001
- [SDR ASAA2023101345635](https://openairdocs.org/sdr/ASAA2023101345635.md): Unknown · unknown · Oct 13, 2023 · N491AS · Boeing 737990ER · Autopilot System
  > AUTOLAND FAIL - AT 30' IN FLARE, APROACH WARN AND AUTO PILOT DISCONNECT. GROUNDED - YES. DFCS BITE SHOWS FLT LEG 1 CHANNEL A 22-11415 & 22-11479, CHANNEL B' 22-11323 & 22-11006, ALL LRU TESTS PASSED FIM 22-11 TASK 801, PERFORMED LAND VERIFIED TEST PASSED AMM 2
- [SDR ASAA2023101045535](https://openairdocs.org/sdr/ASAA2023101045535.md): Unknown · unknown · Oct 10, 2023 · N491AS · Boeing 737990ER · Cabin Cooling System
  > RIGHT PACK CAUTION LIGHT ILLUMS DURING MASTER CAUTION RECALL PRIOR TO DESCENT. EXTINGUISHES WITH RESET. GROUNDED - YES. ON DEFERRAL.
- [SDR ASAA2023100445434](https://openairdocs.org/sdr/ASAA2023100445434.md): Idg · malfunctioned · Oct 4, 2023 · N491AS · Boeing 737990ER · AC Generator-Alternator
  > #2 GENERATOR WOULD NOT COME ONLINE AFTER STARTED. GROUNDED - YES. (RESOLVED ON W/O: 1970734 TASKCARD: N/R-00002) REMOVE AND REPLACE ENG 2 IDG IAW AMM 24-11-11-40-801 PERFROME OPERATIONAL TEST IAW AMM 24-11-00-700-803 ALL TEST PASS GOOD FOR SERVICE OMAR OCHOA
- [SDR ASAA2023092345244](https://openairdocs.org/sdr/ASAA2023092345244.md): Unknown · unknown · Sep 23, 2023 · N491AS · Boeing 737990ER · Engine Bleed Air System
  > DURING ACCOMPLISHMENT OF T/C# 78273000. FOUND #2 ENGINE WITH SHORT TIME FAULT MSG 75304-52 "THE VBV POSITION SIGNALS DISAGREE". GROUNDED - YES. (RESOLVED ON W/O: 1970750 TASKCARD: N/R-00001) ACCOMPLISHED T 78273000. ENGINE #2 IS NOT SHOWING ANY FAULTS IN CURR
- [SDR ASAA2023091045018](https://openairdocs.org/sdr/ASAA2023091045018.md): Unknown · unknown · Sep 10, 2023 · N491AS · Boeing 737990ER · Cabin Cooling System
  > RIGHT PACK LIGHT ILLUMINATED ON RECALL, EXTINGUISHES WITH RESET. GROUNDED - YES. PERFORMED PACK TEMPERATURE CONTROL BITE PROCEDURE REF FIM TASK 21-62 TASK 801. NO FAULTS NOTED. PLACARDS REMOVED. THIS CLEARS MEL 21-32B. SEAMC MITCH NOTIFIED.
- [SDR ASAA2023082844830](https://openairdocs.org/sdr/ASAA2023082844830.md): Valve · faulty · Aug 28, 2023 · N491AS · Boeing 737990ER · Air Intake Anti/De-Ice System
  > AMBER TAI INDICATION ABOVE #2 N1 GAUGE. GROUNDED - YES. CREW STATED THEY DID NOT OPERATE EITHER ENG COWL ANTI-ICE VALVES DURING THIS PARTICULAR FLIGHT. SUSPECT OVERPRESSURE COND DURING ENG OPERATION. PERFORMED OPS CHECK ON #2 ENG COWL ANTI-ICE VALVE VIA APU BL
- [SDR ASAA2023082244739](https://openairdocs.org/sdr/ASAA2023082244739.md): Unknown · unknown · Aug 22, 2023 · N491AS · Boeing 737990ER · Flight Management Computing Hardware System
  > PRIOR TAXI WE RECEIVED AN FMC DISAGREE. GROUNDED - YES. COMPLETED FMC DISAGREE QRH PROCEDURE WHICH RESOLVED THE FMC DISAGREE.
- [SDR ASAA2023081144539](https://openairdocs.org/sdr/ASAA2023081144539.md): Unknown · unknown · Aug 11, 2023 · N491AS · Boeing 737990ER · Cabin Temperature Control System
  > AIR TEMP SOURCE SEL KNOB VERY ERRATIC. WILL DANCE FROM 100F TO 0F & BACK UP ON ITS OWN. KNOB HAS TO BE JIGGLED TO CALM IT DOWN. THEN IT WILL CONTINUE AGAIN. GROUNDED - YES. ON DEFERRAL.
- [SDR ASAA2023072944287](https://openairdocs.org/sdr/ASAA2023072944287.md): Unknown · unknown · Jul 29, 2023 · N491AS · Boeing 737990ER · Cabin Pressure Control System
  > GREEN ALTN LIGHT AND AMBER AUTO FAIL LIGHT ILLUMINATED SHORTLY AFTER LANDING. GROUNDED - YES. ON DEFERRAL.
- [SDR ASAA2023071844114](https://openairdocs.org/sdr/ASAA2023071844114.md): Unknown · unknown · Jul 18, 2023 · N491AS · Boeing 737990ER · Compressor Bleed Control
  > WHILE ACCOMPLISHING T/C 78273000 FOUND SHORT TERM FAULT #75-30452 " VBV POSITION DISAGREE" ON ENG 2. GROUNDED - YES. (RESOLVED ON W/O: 1962312 TASKCARD: N/R-00001) PERFORMED VBV ACTUATOR TEST ON #2 ENGINE REF FIM 75-32 TASK 803 ACTUATOR TEST PASS NO FAULTS NO
- [SDR ASAA2023070943986](https://openairdocs.org/sdr/ASAA2023070943986.md): Unknown · unknown · Jul 9, 2023 · N491AS · Boeing 737990ER · HF Communications System
  > FLIGHT CREW REPORTS THAT WHEN ENTERING CHARACTERS IN SATCOM SCRATCH PAD, (E.G. 12345), RESULTS IN KEY INPUTS APPEARING TO "STICK" (E.G. 1222334). GROUNDED - YES. ON DEFERRAL.
- [SDR ASAA2023070243858](https://openairdocs.org/sdr/ASAA2023070243858.md): Modulating Valve · faulty · Jul 2, 2023 · N491AS · Boeing 737990ER · Cabin Cooling System
  > L & R PACK LIGHT, ON RECALL AFTER ENGINE START. GROUNDED - YES. PERFORMED FIM 21-53 TASK 821, FOUND L+R PZTC ZHOWING "THIS PACK TCV". PERFORMED FIM 21-62 TASK 830 + 831. BOTH TCV V139 + V141 SHOW 115AC. DUE TO RECENT HISTORY - REPLACED P5-17 PANEL. OPWEND /TAG
- [SDR ASAA2023070243823](https://openairdocs.org/sdr/ASAA2023070243823.md): Module · faulty · Jul 2, 2023 · N491AS · Boeing 737990ER · Cabin Temperature Control System
  > CONT CAB TEMPERATURE CONTROLLER IN FULL COLD CONT. CABIN DUCT TEMP READS 44C AND INCREASINGLY STEADILY FLIGHT DECK TEMP UNABLE TO CONTROL. GROUNDED - YES. FOLLOWED FIM PACK TEMP CONTROL - BITE B737-900 FIM 21 62 TASK 801 FOUND FLT DECK SELECTOR FAULT - FOLLOWE
- [SDR ASAA2023070143886](https://openairdocs.org/sdr/ASAA2023070143886.md): Unknown · unknown · Jul 1, 2023 · N491AS · Boeing 737990ER · Electrical Power System
  > BEFORE T.O.D PASSENGER IN SEAT 3D REPORTED LIGHT SMOKE UPON PLUGGING INTO ELECTRICAL OUTLET. THEY IMMEDIATELY UNPLUGGED AND SMOKE STOPPED. GROUNDED - YES. ON DEFERRAL.
- [SDR ASAA2023063043833](https://openairdocs.org/sdr/ASAA2023063043833.md): Switch · inoperative · Jun 30, 2023 · N491AS · Boeing 737990ER · Aircraft Fuel System
  > CAPT REPORTED RIGHT AFT PUMP LOW PRESSURE LIGHT WAS INOP. GROUNDED - YES. TROUBLESHOT TO VERIFY LIGHT; LOW PRESSURE WAS INOP. REMOVED AND REPLACED FUEL BOOST PUMP PRESSURE SWITCH. OPS CHECK GOOD, REF B737-900 AMM 28-42-11.
- [SDR ASAA2023062643770](https://openairdocs.org/sdr/ASAA2023062643770.md): Unknown · unknown · Jun 26, 2023 · N491AS · Boeing 737990ER · Fuel Controlling System
  > BOTH EEC'S ALTN MODE AFTER ENGINE START. GROUNDED - YES. BOTH EEC'S TEST GOOD - NO FAULTS UPON ARRIVAL AT A/C - FOUND P5-68 POWER MANAGEMENT MODULE ENG. 1&2 SWITCHS IN THE ALTERNATE POSITION. SWITCHED BOTH TO NORMAL (ON)_ POSITION. REF. FIM 73-05 TASK 811, PER
- [SDR ASAA2023061943636](https://openairdocs.org/sdr/ASAA2023061943636.md): Spinner · eroded · Jun 19, 2023 · N491AS · Boeing 737990ER · Turbine Engine Air Inlet Section
  > DURING #2 ENGINE FAN LUBE ASA TASK CARD 78472010 FRONT SPINNER CONE EROSION BEYOND LIMIT. GROUNDED - YES. REPLACED FRONT SPINNER CONE #2 ENGINE REF ASA TASK CARD 78472010.
- [SDR ASAA2023061843613](https://openairdocs.org/sdr/ASAA2023061843613.md): Unknown · unknown · Jun 18, 2023 · N491AS · Boeing 737990ER · Aircraft Fuel System
  > RIGHT AFT FUEL PUMP LO PRESSURE LIGHTS DO NOT ILLUMINATE WITH PUMP SELECTED OFF. LIGHTS DO TEST WHEN PRESSED ON WITH LIGHT TEST. GROUNDED - YES. CLEANED AND REINSTALLED RIGHT AFT FUEL PUMP PRESSURE SWITCH CONNECTOR AND PERFORMED OPS CK AND OPS NORMAL REF B737-
- [SDR ASAA2023061043515](https://openairdocs.org/sdr/ASAA2023061043515.md): Unknown · unknown · Jun 10, 2023 · N491AS · Boeing 737990ER · Flight Management Computing Hardware System
  > P18-2 A9 CB POPPED DATA LOADER. GROUNDED - YES. RESET CIRCUIT BREAKER PER B737-900 AMM 20-60-01 DATA LOADER OPS CHECKS NORMAL.
- [SDR ASAA2023052543456](https://openairdocs.org/sdr/ASAA2023052543456.md): Battery Pack · no test · May 25, 2023 · N491AS · Boeing 737990ER · Emergency Lighting
  > EMERGENCY LIGHTS BATTERY PACK AT RH FS 500C+7.5 FAILS CAP CHECK GROUNDED - YES. REMOVED, REPLACED BATTERY PACK S/N 409598 AND OPS CHECK GOOD EMER LIGHT AT R2 DOOR IAW B737-900 AMM 33-51-06-960-805.
- [SDR ASAA2023052543358](https://openairdocs.org/sdr/ASAA2023052543358.md): Lamp · inoperative · May 25, 2023 · N491AS · Boeing 737990ER · Emergency Lighting
  > EMERGENCY EXIT LIGHT OUTSIDE AFT LEFT OVERWING EXIT INOP. GROUNDED - YES. REMOVED, REPLACED AND OPS CHECK GOOD EMER LIGHT OUTSIDE AFT LEFT OVERWING EXIT IAW B737-900 AMM 33-51-06-960-801.
- [SDR ASAA2023052443364](https://openairdocs.org/sdr/ASAA2023052443364.md): Unknown · unknown · May 24, 2023 · N491AS · Boeing 737990ER · Emergency Lighting
  > MULTIPLE INTERIOR & EXTERIOR EMERGENCY EXIT LIGHTS INOP R2 ABOVE & SIDE (INTERIOR) L2 ABOVE & SIDE (INTERIOR) L1 ABOVE & SIDE (INTERIOR) LEFT AFT WING EMER EXIT (EXTERIOR) R2 (EXTERIOR). GROUNDED - YES. DEEP-CYCLE PROCEDURE ACCOMPLISHED FOR ALL APPLICABLE EMER
- [SDR ASAA2023052143443](https://openairdocs.org/sdr/ASAA2023052143443.md): Battery · inoperative · May 21, 2023 · N491AS · Boeing 737990ER · Emergency Lighting
  > EMERGENCY LIGHT AT ROW 27L INOP GROUNDED - YES. REPLACED POWER SUPPLY/BATTERY PACK S/N 409499 FOR EMERGENCY LIGHT AT ROW 27L
- [SDR ASAA2023050343134](https://openairdocs.org/sdr/ASAA2023050343134.md): Unknown · unknown · May 3, 2023 · N491AS · Boeing 737990ER · Cabin Cooling System
  > RH PACK LIGHT ILLUMINATED ON RECALL EXTINGUISHED WITH MASTER CAUTION RESET. GROUNDED - YES. PERFORMED PACK TEMP CONTROL BITE TEST FOUND LOOSE TRIM VALVE FAULT PERFORMED B737-900 FIM TASK 21-22 TASK 835 FAULT CORRECTED
- [SDR ASAA2023042543039](https://openairdocs.org/sdr/ASAA2023042543039.md): Acm · faulty · Apr 25, 2023 · N491AS · Boeing 737990ER · Cabin Cooling System
  > DURING OPERATION OF R/H PACK. PACK TRIP OFF LIGHT ILLUMINATES AND WILL NOT RESET. GROUNDED - YES. ACCOMP PZTC BITE CK R/H PACK TCV FAULTED. REF B737-FIM 21-62 TASK 801. RMVD/RPLCD R/H PACK TCV LK CK GOOD BUT R/H PACK DISCHARGE TEMP CLIMBS TO 90 DEG C AND PACK
- [SDR ASAA2023041742944](https://openairdocs.org/sdr/ASAA2023041742944.md): Unknown · unknown · Apr 17, 2023 · N491AS · Boeing 737990ER · Cabin Cooling System
  > RIGHT PACK LT ILLUM ON MC RECALL EXTINGUISHES WITH RESET. GROUNDED - YES. PERFORMED BITE TEST ON ZONE TEMP CONT UNITS, REF B737-900 AMM 21-61-00-700-806-002; FOUND SRADA EXIT ACTUATOR FAULT ON CONT 2. ACCOMP B737-900 FIM 21-53 TASK 821. PZTC BITE CK ACCOMPLIS
- [SDR ASAA2023032742614](https://openairdocs.org/sdr/ASAA2023032742614.md): Unknown · unknown · Mar 27, 2023 · N491AS · Boeing 737990ER · Auto Throttle System
  > ON TAKE OFF A/T DISCONNECTED AND FAILED TO RE ENGAGE ON TAKE OFF OR CRUISE. GROUNDED - YES. PERF A/T BITE PER B737-900 FIM 22-31 TASK 801. ALL REQ TESTS PASSED, NO DEFECTS FOUND AT THIS TIME. PERF LLM TEST REF B737-900 AMM 22-11-00. ALL REQ TESTS PASSED. AC AP
- [SDR ASAA2023021341961](https://openairdocs.org/sdr/ASAA2023021341961.md): Valve · faulty · Feb 13, 2023 · N491AS · Boeing 737990ER · Cabin Cooling System
  > PACK 2 ILLUMINATED ON RECALL. GROUNDED - YES. ACCOMPLISHED PACK TEMPERATURE CONTROL BITE PROCEDURE REF B737-900 FIM 21-62 TASK 801. #2 CONTROLLER SHOWS THIS PACK TCV HARD FAIL. R & R RIGHT PACK TCV V141 REF B737-900 AMM 21-51/401 OPS CK GOOD.
- [SDR ASAA2023012641662](https://openairdocs.org/sdr/ASAA2023012641662.md): Modulating Valve · faulted · Jan 25, 2023 · N491AS · Boeing 737990ER · Cabin Temperature Control System
  > CONT CAB TEMP. UNCONTROLLABLE, DUCT SUPPLY 40 DEGREE C LEFT PACK TEMP 50 DEGREE C. GROUNDED - YES. REMOVED AND REPLACED TEMP CONTROL VALVE ON LH PACK AS REQUIRED LEAK CKD GOOD NO LEAKS OPS CKD GOOD. REF AMM 21-51-10-400-801 PERFORMED TEMP CONTROLLER BITE TEST
- [SDR ASAA2023012641660](https://openairdocs.org/sdr/ASAA2023012641660.md): Modulating Valve · faulted · Jan 25, 2023 · N491AS · Boeing 737990ER · Cabin Temperature Control System
  > CONT CAB TEMP CONTROL KNOB WILL MODULATE THE CONT CAB SUPPLY DUCT TEMPERATURE UP + DOWN WITH A MOVEMENT UP + DOWN BY THE KNOB. THE LOWEST TEMPERATURE WE COULD ACHIEVE WAS 50'C HOWEVER- TOO HOT!. GROUNDED - YES. REMOVED AND REPLACED LH PACK TEMP CONTROL VALVE R
- [SDR ASAA2023012641661](https://openairdocs.org/sdr/ASAA2023012641661.md): Modulating Valve · faulted · Jan 24, 2023 · N491AS · Boeing 737990ER · Cabin Cooling System
  > LEFT PACK LIGHT ILLUMINATES ON RECALL AND EXTINGUISHES WITH MASTER CAUTION RESET. GROUNDED - YES. REMOVED AND REPLACED LH PACK TEMP CONTROL VALVE REF B737-900 AMM 21-51-10-400-801 (ASA L/P 60116284).
- [SDR ASAA2023012391587](https://openairdocs.org/sdr/ASAA2023012391587.md): Satcom · inoperative · Jan 19, 2023 · N491AS · Boeing 737990ER · Communications System
  > SAT 2 NOT WORKING. FMC SHOWS SAT2 NOT READY/FAIL. SAT 1 STILL WORKING FINE. GROUNDED - YES. PERFORMED SATCOM SYSTEM TEST REF B737-900 AMM 23-15-00. OPS CHECKS GOOD. ORIG SUB DATE: 1/23/2023
- [SDR ASAA2023010141409](https://openairdocs.org/sdr/ASAA2023010141409.md): Light · inoperative · Jan 1, 2023 · N491AS · Boeing 737990ER · Emergency Lighting
  > DURING ACCOMPLISHMENT OF ASA T/C 78233008 "EMERGENCY LIGHTS-OPS CHECK" EMERGENCY ISLE LIGHT AT SEAT ROWS 25DEF AND 30DEF ARE INOP OPPOSITE ISLE EMERGENCY LIGHT OPS CHECKED NORMAL. GROUNDED - YES. VERIFIED DISCREP. FOUND EMERGENCY BATTERY PACK TO SAME INOP LIGH
- [SDR ASAA2022123041326](https://openairdocs.org/sdr/ASAA2022123041326.md): Warning Light · false activation · Dec 30, 2022 · N491AS · Boeing 737990ER · Cabin Cooling System
  > #2 PACK LIGHT ILLUMINATES ON MASTER CAUTION RECALL. PACK LIGHT EXTINGUISHES UPON MASTER CAUTION RESET. GROUNDED - YES. ACCOMPLISHED PACK ZONE TEMP CONTROL BITE PER B737-900 FIM 21-62 TASK 801. LOGGED EXIT, FAULT CLEARED.

Next page: https://openairdocs.org/aircraft/N491AS/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 = 'N491AS' AND registry_match = 'registration'
ORDER BY difficulty_date DESC
```

This list as a web page: https://openairdocs.org/aircraft/N491AS/reports

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