JASC 4990

Service difficulty reports · 2,651

Reports filed under 4990 · APU Oil System, newest first.

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 jasc_code = '4990'
  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.

SDR AALA202605212742O-Ring · leakingAIRCRAFT WAS GROUNDED: STRONG ODOR IN THE ENTIRE CABIN. MAINTENANCE FOUND APU OIL COOLING FAN LEAKING. REPLACED O-RING IAW AMM 49-52-51. LEAK CHECK GOOD.May 18, 2026 · N705UW · Airbus A319112SDR JJBA20260518011Oil System · overservicedFUMES SMELLED ON TO ON OCF FROM SURFACE TO 2000 FT  SIMILAR TO GASOLINE NOT JET A. INSPECTED E1/E2 INLETS. T/S USING FIM. FOUND BURNT OIL ODOR WOULD OCCUR WHEN RUNNING PACKS OFF OF APU. INSPECTED APU FOR SIGNS OF OVERSERVICING. FOUND APU OIL OVER SERVICED ABOVMay 14, 2026 · N16147 · Emb EMB145XRSDR DALA2026051302985Oil System · leakingDESCENDING THROUGH 4000 CA AND FO BOTH BEGAN TO SMELL A DIRTY SOCK FUME. THE SMELL BECAME STRONGER AND SLIGHTLY MORE ACRID DURING THE REMAINDER OF THE DESCENT. FWD FA'SQUIRED BUT DID NOT SMELL THE ODOR. UPON LANDING THE COCKPIT WINDOWS WERE OPENED AND THE ODORMay 12, 2026 · N860DN · Boeing 737932ERSDR AALA202605138724Seal · leakingAIRCRAFT WAS GROUNDED: ON DESCENT STRONG DIRTY SOCK SMELL. APU WAS NOT USED AT ALL DURING FLIGHT. MAINTENANCE REPLACED LUBE MODUL E SEAL PLATE IAW AMM 49-32-11.May 10, 2026 · N9023N · Airbus A319115SDR AALA202605111045Oil System · leakingAIRCRAFT WAS GROUNDED: DIRTY SOCK SMELL DURING IDLE DECENT. FOUND OIL LEAKING FROM V-BAND SEAL. MAINTENANCE REPLACED APU IAW J/C 26L31049003.May 7, 2026 · N9018E · Airbus A319115SDR AALA202605052817Lubrication Unit · leakingAIRCRAFT WAS GROUNDED: FLIGHT ATTENDANTS REPORT THAT THERE WAS A PLASTIC BURNING ODOR COMING FROM ROWS 11 TO 30. MOST PROMINENT DURING TAKEOFF AND DESCENT. MAINTENANCE FOUND THE APU LEAKING AND REPLACED THE FCU PER AMM 49-32-11 AND THE LUBE MODULE PER AMM 49-May 1, 2026 · N177US · Airbus A321211SDR AALA202604287047Oil System · leakingAIRCRAFT WAS NOT GROUNDED: REPEATED WRITE UP. MUSTY ODOR IN THE FLIGHT DECK AND AFT GALLEY. ODOR OF DIRTY SOCKS AND BURNING RUBBER REPORTED FROM FLIGHT ATTENDANT IN THE AFT GALLEY. ACCOMPLISHED WORK CARD 08L00021001. FOUND LT AND RT PACK BAY TO HAVE OIL RESIApr 27, 2026 · N969AN · Boeing 737823SDR AALA202604279795Module · leakingAIRCRAFT WAS GROUNDED: AIRCRAFT FUMES WHILE DESCENDING OUT OF FL180. ACRID SOCK SMELL. MAINTENANCE REPLACED APU OIL LUBE MODULE GTCP PER AMM 49-91-45. **SUPPLEMENTAL REPORT FOR SDR AALA202604249795 SUBMITTED BY DFW 4/24/26.Apr 22, 2026 · N760US · Airbus A319112SDR I5PA2026042175702Solenoid · failedPERFORMED APU BITE PER FIM. FOUND LOW OIL PRESS APU DE-OIL SOLENOID FAULTY. REPLACED SAME PER AMM. OPS AND LEAK CHECK OK. SUCCESSFUL APU INFLIGHT START PERFORMED.Apr 21, 2026 · N757QM · Boeing 75729JSDR WX0A2026042232792Oil System · leaking(AIRCRAFT NOT GROUNDED) DIRTY SOCK SMELL ON DESCENT REPORTED STRONGEST AFT CABIN / PERFORMED TC A32X-21-000-001 & AMM 21-00-00-615-802-A. FOUND OIL LEAKING AROUND APU INTAKE AND COMPRESSOR. APU PLACED ON MEL ON LOGPAGE 2171449. TRACKING ODOR EVENT ON MDDR 23Apr 20, 2026 · N322NV · Airbus A319111SDR CALA2026041715430Apu · oil consumptionLEVEL TWO CHRONIC, APU LOW OIL MESSAGE. INDICATION SYS HAS BEEN CONFIRMED TO BE OPERATING CORRECTLY. CURRENTLY APU IS CONSUMING ONE QUART EVERY 8 HOURS. REF TSM 49-00-00-810-979-A AND AMM 49-00-00-810-979. CHECK FOR LEAKS FROM APU DRAINS SUCH AS FUEL CONTOL, AApr 14, 2026 · N447UA · Airbus A320232SDR AALA202604148941Apu · leakingAIRCRAFT WAS GROUNDED: MUSTY SOCK SMELL ON APPROACH ON FLIGHT DECK. FAS DID NOT SMELL IT IN CABIN. TURNED OFF BOTH ACMS AND CABIN FANS AND SMELL DISSIPATED. MAINTENANCE ACCOMPLISHED DECONTAMINATION OF ECS NO LEAKS NOTED IAW JC 26L00021014 REF MIC #7236419.Apr 11, 2026 · N9002U · Airbus A319115SDR DALA2026041102303Generator · leakingAIRCRAFT 3031, DIRTY SOCK SMELL FROM PACKS AT ALL PHASES OF FLIGHT. FOUND APU GEN LEAKING OIL FROM THE CASE. REMOVED & REPLACED APU GEN PER A320 AMM 24-23. OPS CHECK AND LEAK CHECKS GOOD. (LP 8610375 - AIRCRAFT WAS GROUNDED)Apr 10, 2026 · N331DN · Airbus A321213SDR DALA2026040802235Plenum · contaminatedOIL ODOR THROUGHOUT CABIN & COCKPIT ON ACFT ENTRY. APU LEAK CHK & INSP FOR CONTAMINATION C/W ON LOG 8044937, COMPLETES SMOKE AND FUMES WORKCARD 0550-2002 AND 0550- 2001 AND DUE TO PREVIOUS HIS ON NR 2 ENG. COMPLETED ENG 1 & 2 BOROSCOPE WORKCARD 7900-2001. REIApr 6, 2026 · N335NB · Airbus A319114SDR DALA2026040702203Cooling Fan · leakingFUMES - DESCENDING AT FL140 UNTIL LANDING, CREW REPORTED DIRTY SOCK ODOR. DECLARED EMERGENCY AND DONNED OXYGEN MASKS. APU WAS ON MEL FROM PRIOR EVENT IN YYZ. FOUND APU COOLING FAN AND FCU LEAKING OIL. REPLACED COOLING FAN AND FCU. INLET DOOR CONTAMINATED WITApr 6, 2026 · N373NW · Airbus A320212SDR DALA2026040602164Oil System · leakingUPON ARRIVING AT THE AIRCRAFT APU WAS RUNNING AND SMELLED LIKE DIRTY SOCKS. TURNED OFF APU BLEED, SMELL IMPROVED. TURNED APU BLEED BACK ON, SMELL INCREASED. INTIAL INVESTIGATION FOUND APU OVER SERVICED. REMOVED EXCESS OIL IAW AMM 49-80. UPON FURTHER INVESTIGAApr 2, 2026 · N347NB · Airbus A319114SDR YENA2026040300370Oil System · leakingFLT 472, FLL-LGA . REF LG PG 4630858 ITEM 1. APU ODOR & LEAKS. LVL B DECONTAMINATION REQ.; PERFORMED LVL B REMOVAL OF CONTAMINATION OF ECS IAW INFO NOTICE 2017-T015M STEPS 1 & 2. APU ODOR TYPE 1. DECONTAMINATION CW IAW AMM 21-00-00-615-803. A/C OK FOR SVC."Apr 2, 2026 · N519JB · Airbus A320232SDR AALA202604020189Oil System · leakingAIRCRAFT WAS GROUNDED: UPON DECENT ACRID SMELL IN THE REAR OF THE AIRPLANE. MAINTENANCE FOUND APU LEAKING OIL AND REPLACED APU REF: NR 0135398.Mar 30, 2026 · N70020 · Airbus A319115SDR DALA2026033002057Oil System · leakingHAD MUSKY SMELL WHEN TURNING ON APU BLEED. SMELL WENT AWAY RIGHT AFTER FEW SECONDS. FOUND APU TO BE THE SOURCE, LEAKING INTERNALLY. REPLACED APU, PER AMDS # 4900-9002 OPS CHECK & LEAK CHECK GOOD. (LP 8306544)Mar 30, 2026 · N382DN · Airbus A321211SDR AALA202603275442Plug · leakingAIRCRAFT WAS GROUNDED: REF MIC 7196981 SOF EVENT. MAINTENANCE FOUND EVIDENCE OF DRY HYDRAULIC FLUID IN AND AROUND THE APUPLENUM AND BULK HEAD SEAL AND THE COOLING FAN. FOUND APU GEN DRAIN PLUG LEAKING. REMOVED AND REPLACED APU GEN DRAIN PLUG O-RING IAW AMM 24-Mar 25, 2026 · N751UW · Airbus A319112SDR AALA202603272567Solenoid Valve · leakingAIRCRAFT WAS GROUNDED: SOF EVENT. SMELL WAS REPORTED BY CABIN CREW AS BURNT RUBBER OR VERY HOT PLASTIC. MILD ODORS WERE NOTED FOLLOWING TAKEOFF BUT WERE NOT OBTRUSIVE OR IMPAIRING AND APPEARED TO DISSIPATE. THE ODOR RETURNED ON DECENT. MAINTENANCE REPLACED AMar 23, 2026 · N760US · Airbus A319112SDR GTIA2026032639321Oil System · overservicedFLIGHT ATTENDANT REPORTED AN ODOR OF HUMIDITY & VOMIT, ODOR IN FRONT & AFT CABIN ON FINAL APPROACH, ABOUT 2,000 FT. FOUND APU OVERSERVICED DURING INSPECTION OF THE APU UPON ODOR IN THE CABIN IAW TSM 05-50-00-810-831-A, & AMM 49-00-00-200-811-A , DRAINED APUMar 23, 2026 · N920NK · Airbus A320271NSDR DALA2026031901912Carbon Seal · leakingAIRCRAFT 9518, STRONG DIRTY SOCK ODOR COMING FROM PACK 2. FOUND APU TO BE LEAKING THROUGH CARBON SEAL PER B717 AMM 49-00. REPLACED APU. (LP 8237910)Mar 16, 2026 · N959AT · Boeing 717200SDR YENA2026031600302Oil System · leakingFLT 65 BOS- RSW. DIRTY SOCK FUME EVENT DESCENDING INTO RSW BELOW 10000' LEVEL 2. PERSISTANT FUME/ODOR MILD IRRITAITON OF THROAT FOR CREWMEMBERS.; COMPLIED WITH INFORMATION NOTICE 2017-T015 STEPS 1&2 FOUND APU LEAKING OIL INTERNALLY DECONTAMINATION A WAS ACCOMMar 14, 2026 · N593JB · Airbus A320232SDR YENA2026031600306Oil System · leakingFLT 548 TPA - HPN. FUME EVENT REPORTED BY INFLIGHT AT 13000, SMELL BY FLIGHT CREW. SMELLED LIKE BURNING CRAYONS SMELL PERSITIED AND GREW STRONGER ALL THE WAY TO THE GATE ROW 19 TO AFT VERY STRONG BY F4 & F1 NOSTRILS BURNING , NAUSEA.; COMPLIED WITH INFO NOMar 13, 2026 · N655JB · Airbus A320232SDR DALA2026031001657Oil System · leaking(LOG 8395700) WHILE AT THE GATE JUST PRIOR TO PUSH FLIGHT ATTENDANTS REPORTED A KNOCKING SOUND IN AFT GALLEY. NOISE AND VIBRATION COULD ALSO BE FELT IN THE COCKPIT. THERE WAS ALSO A SLIGHT ODOR OF EXHAUST. VERIFIED APU AT FAULT, MCD FULL OF METAL. VERIFIED NO Mar 7, 2026 · N955DZ · Boeing 7379GPERSDR AALA202603061176Oil System · leakingAIRCRAFT WAS GROUNDED: SMELL OF WET SOCKS BY MAIN CABIN ENTRY DOOR DURING ALL PHASES OF FLIGHT AS REPORTED BY THE FLIGHT ATTENDANTS. MAINTENANCE FOUND THE APU LEAKING OIL AT THE V BAND SEAL AND REPLACED THE APU PER JOB CARD 26L310449003.Mar 3, 2026 · N524UW · Airbus A321231SDR GTIA2026030539290Oil System · leakingMODERATE ODOR FROM AIR CONDITIONING LIKE EXHAUST DURING CLIMB DISIPATED AT LEVEL OFF. ISOLATED PACK 1. NO FURTHER ODOR UNTIL DECENT ON BASE LEG THEN STRONG DIRTY SOCK SMELL IN CABIN WITH PACK 2 ONLY. SOURCE, CABIN AIR SUPPLY VENTS. FWD, MID, AND AFT CABIN.Mar 3, 2026 · N602NK · Airbus A320232SDR 2026F00021Warning Message · illuminatedQRF TO ORIGIN AIRPORT DUE TO APU OIL PRESS CAUTION MESSAGE ON EICAS, GEN NR 2 WAS DEFERRED, SO UNNABLE TO OPERATE WITH ON ELECTRICAL SOURCE ONLY. PERFORMED FIM 49-61-00, OPS TESTED OK.Mar 2, 2026 · Cndair CL6002B19SDR YENA2026030200244Oil System · overservicedFLT #217 PHL-FLL." DIRTY SOCK/OILY SMELL DURING DESCENT @ 10,000' IDLE POWER, VMC,COCKPIT ONLY.; COMPLY INFO NOTICE 2017-T015M. ISOLATE FOR TYPE 1 APU OIL OVERSERVICED. REMOVED EXTR APU OIL IAW AMM 12-13-49. PER TSM 05-50-00-810-085 A/C IS OK FOR SVC "Feb 27, 2026 · N606JB · Airbus A320232SDR DALA2026022401311Oil System · leakingON BOARDING ACFT WITH APU RUNNING, A STRONG ODOR WAS NOTICED. IT SMELLED LIKE A MUSTY BURNING OVEN CLEANER. THE APU BLEED WAS TURNED OFF NO VISIBLE ODOR WAS NOTICED. ODOR WAS IN COCKPIT AND CABIN. ISOLATED SOURCE OF SMOKE & FUME ODOR TO APU OIL LEAK. C/W WFeb 20, 2026 · N373NW · Airbus A320212SDR AALA202603064157Garlock Seal · leakingAIRCRAFT WAS GROUNDED: APU OFF DESCENDING THROUGH 10000, FLIGHT CREW NOTED A DIRTY SOCK SMELL IN FLIGHT DECK. **ORIGINAL REPORT WAS AALA202602236304 SUBMITTED 2/23/2026 BY TUL** MAINTENANCE FOUND EVIDENCE OF COKING IN THE APU GEARBOX VENT TUBE AND REPLACED IT Feb 19, 2026 · N921US · Airbus A321231SDR YENA2026021800217Oil System · leakingFLT 1247, LGA-TPA. BOTH AFT FA'S SAID THEY SMELLED A DIRTY SOCKS ODOR AT 7000 FT DURING DESCENT. SCRATCHY THROAT & BURNING EYES.; ACCOMPLISHED INFO NOTICE 2017-T015M REFER TSM 05-50-00-810-831-A, FOUND DIRTY SOCKS ODOR ACTIVE DURING APU BLEED ON AND PACKS Feb 17, 2026 · N558JB · Airbus A320232SDR AALA202602209727Oil System · leakingAIRCRAFT WAS GROUNDED: AN EMERGENCY WAS DECLARED INBOUND INTO FLL DUE TO THE FLIGHT CREW REPORTING A VERY MUSTY ODOR DESCENDING THROUGH 15000 FEET AND IT GOT WORSE UNTIL LANDING. MAINTENANCE FOUND THE APU LEAKING OIL AND REPLACED IT PER TASK CARD 26L31049003Feb 15, 2026 · N900UW · Airbus A321231SDR F3LA202602170370Oil System · leakingREFERENCE LP533532 ITEM #1 FUME EVENT AFT CABIN VERY STRONG MOVED TO FORWARD CABIN DIRTY SOCK SMELL., AC WAS GROUNDED AS A RESULT OF THE SDR REPORTABLE EVENT. FERRY FLIGHT FROM ELP TO LAS PLACED APU ON MEL, TRANSFERRED TO NON-ROUTINE REF NR141160 FOR MX ACTIOFeb 13, 2026 · N317FR · Airbus A320251NSDR AALA202602124309Oil Cooler · leakingAIRCRAFT WAS GROUNDED: STRONG ODOR PRESENT UPON BOARDING JET. APU AND PACKS ON. PILOT REFUSED AIRCRAFT DUE TO HISOTRY OF ODORS. MAINTENANCE FOUND APU OIL COOLING FAN SEAL LEAKING AND REPLACED THE OIL COOLER.Feb 11, 2026 · N70020 · Airbus A319115SDR DALA2026021100963Oil System · leakingRETURNED TO SEA DUE TO STRONG OIL ODOR IN THE CABIN AND FLIGHT DECK. TROUBLESHOT LT & RT ENGINES, PERFORMED OIL DECONTAMINATION, FOUND OIL LEAKING FROM APU GEN HOUSING, DEFERRED APU PER MEL 49-11-01. (8445066)Feb 11, 2026 · N417DX · Airbus A330941SDR DALA2026021000949Oil System · overservicedON TAKEOFF ROTATION CAPTAIN & FIRST OFFICER NOTICED A BURNED RUBBER ODOR AND DISAPATED IN 20 SECONDS. FOUND APU OIL OVERSERVICED. SERVICED APU OIL IAW AMM 12-13.Feb 9, 2026 · N833DN · Boeing 737932ERSDR DALA2026020900911Clamp · leakingSMOKE AND ODOR IN CABIN, NO PASSENGERS ABOARD, ONLY CREW AND MTC. FOUND EXTERNAL LEAK AT TEE CLAMP BETWEEN GEARBOX AND INLET COMPRESSOR. OPENED PLENUM FOUND INLET CONTAMINATED WITH OIL. CLEANED CONTAMINATION FROM INLET PLENUM, R & R COALESCER BAGS IAW AMM Feb 8, 2026 · N933AT · Boeing 717200SDR SWAA2026021069486Lubrication Unit · faultedAPU SHUTDOWN IN FLIGHT. R & R APU LUBE MODULE IAW AMM 49-91-11.Feb 6, 2026 · N8541W · Boeing 7378H4SDR AALA202602172244Valve · leakingAIRCRAFT WAS GROUNDED: DURING DESCENT STRONG ODOR PRESENT IN FLIGHT DECK AND AFT GALLEY. MOSTLY ASSOCIATED WITH POWER CHANGES. IMPROVED IN FLIGHT DECK AFTER CROSS-BLEED SELECTED TO SHUT. STRONGER IN AFT GALLEY AFTER CROSS-BLEED SHUT. MAINTENANCE FOUND THE APUFeb 2, 2026 · N9010R · Airbus A319115SDR AALA202602138516Lubrication Unit · leakingAIRCRAFT WAS GROUNDED: DIRTY SOCK ODOR ON DESCENT APPROXIMATELY 14000' NORMAL PACK CONFIGURATION APU OFF. MAINTENANCE FOUND THE APU LUBE MODULE SCAVENGER FILTER HOUSING LEAKING OIL AND INSTALLED A NEW O-RING PER AMM 49-91-41. A DECONTAMINATION OF THE ENVIRONFeb 2, 2026 · N510UW · Airbus A321231SDR DALA2026020800894Generator · leakingPASSING THROUGH 8000 ON ARRIVAL INTO MIA THROTTLES IDLE, SMELLED STRONG ODOR, NO VISIBLE SMOKE, STAYED SAME FOR ARRIVAL, FORWARD FA DID NOT DETECT ANYTHING. FOUND OIL CONTAMINATION ON APU AS RESULT DEFERRED PER MEL 49-10-01A. LATER, FOUND LUG ON APU GENERATOJan 30, 2026 · N383DZ · Airbus A321211SDR AALA202602091980Separator · leakingAIRCRAFT WAS GROUNDED: MUSTY SOCK SMELL IN DESCENT TO WARM MOIST CLIMATE AT AUA. FLIGHT CREW REPORTED IT SMELLED STRONG IN CABIN SEAT 4C AND VERY STRONG FROM FLIGHT DECK OVERHEAD VENTS. **ORIGINAL REPORT WAS AALA202602024344 SUBMITTED 2/2/26 BY TUL** MAINTENANJan 29, 2026 · N957XV · Airbus A321253NSDR AALA202602094344Vent Line · cloggedAIRCRAFT WAS GROUNDED: MUSTY SOCK SMELL IN DESCENT TO WARM MOIST CLIMATE AT AUA. FLIGHT CREW REPORTED IT SMELLED STRONG IN CABIN SEAT 4C AND VERY STRONG FROM FLIGHT DECK OVERHEAD VENTS. MAINTENANCE REPLACED THE APU GEARBOX VENT LINE PER AMM 49-26-55 AND THE AJan 29, 2026 · N957XV · Airbus A321253NSDR CALA2026012913422Oil System · leakingAPU FIRE AT GATE AFTER OIL SVC RAN APU TO VERIFY NO SIGNS OF OIL OR FUEL LEAKS REF FIM 49-10341. MECHANIC SAW SIGN OF OIL LEAK WHICH CAUGHT FIRE. C/W APU INSPECTION IAW AMM 49-11-00-04G-311A UPDATED. APU INSP NOTED, NEEDS TO BE C/W REF ASSOCIATED LP 7737965Jan 27, 2026 · N12003 · Boeing 78710SDR DALA2026012900705Oil System · leakingFUMES AFTER LANDING. MODERATE INTENSITY PRESENT IN FLT DECK & FWD CABIN APU ON BLEED OFF. C/W W/C 0550-2002. AFTER NR 1 ENGINE & APU INSPECTION FOUND OIL POOLING AT BOTTOM OF APU GENERATOR AND SIGNS OF DE-ICING FLUID IN APU BAY. IAW MCC REQUEST PERFORMED A LJan 27, 2026 · N345NB · Airbus A319114SDR CALA2026012613252Oil System · overservicedAPU PANDA LIST HAS IDENTIFIED A PERSISTENT EXHAUST ODOR IN CABIN AND RECOMMENDS TROUBLESHOOTING IAW FIM 49-11 FT 895. UPDATE LOG WITH FINGINGS. CARRIED BY ELB PERFORMED FIM 49-11-4FT895, EXAMINED THE COMPRESSOR DISCHARGER AND BLEED AIR DUCT. FOUND NO OIL CONTAJan 26, 2026 · N57863 · Boeing 75733NSDR WX0A2026012832716Oil System · leaking(AIRCRAFT NOT GROUNDED) DIRTY SOCK/MUSTY/CLEANING SUPPLY SMELL ON TAKEOFF AND LASTING APPROXIMATLY TWO MINUTES AFTER TAKEOFF. SMOKE ODER FUMES WORKSHEET FILLED OUT. DURING COMPLETION OF TC 21-000-002 FOUND OIL LEAKING FROM FCU DRAIN TUBE. COMPLIED WITH TC. DJan 20, 2026 · N205NV · Airbus A320214SDR SWAA2026012262812Lubrication Unit · faultedNR 1 IDG ON MEL. APU AUTO SHUTDOWN IN FLIGHT. REMOVED AND REPLACED LUBE MODULE IAW AMM 49-91-11.Jan 19, 2026 · N7879A · Boeing 7377K9
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