# JASC 2911: Hydraulic Power Accumulator, Main

- Type: JASC system/component code (FAA)
- ATA chapter: 29 Hydraulic Power
- Title in the code table: HYDRAULIC POWER ACCUMULATOR, MAIN
- Service difficulty reports: 202
- FAA code table: https://www.faa.gov/sites/faa.gov/files/JASC_Code.pdf#page=29
- Page: https://openairdocs.org/jasc/2911

## What it covers

The component that provides for pressure surges to maintain a constant pressure in the system. Typical parts are accumulator, seal, end cap, air valve, etc.

## Service difficulty reports (202, newest 50)

- [SDR FDEA202607291051](https://openairdocs.org/sdr/FDEA202607291051), Jul 29, 2026: Doug MD11F. HYDRAULIC SYSTEM. FAILED. FLIGHT STARTED WITH MEL 29-08-01-01 OPERATING WITH HYD MANUAL. PASSING THROUGH APPROXIMATELY 5000 FT, HYD 2L OFF ALERT C (N583FE)
- [SDR 4DSR2026063001](https://openairdocs.org/sdr/4DSR2026063001), Jun 30, 2026: Pilats PC1245. SELECTOR VALVE. LEAKING. LANDING GEAR HYD. ACCUMULATOR MOTOR CYCLED IN FLIGHT CAUSING CAUTION TO COME ON. AIRCRAFT WAS JACK AND TROUBLESHOT, FOUN (N497PC)
- [SDR DALA2026062903844](https://openairdocs.org/sdr/DALA2026062903844), Jun 28, 2026: Boeing 717200. ACCUMULATOR. LEAKING. ATB- RETURNED TO DTW DUE TO A LEFT HYDRAULIC QUANTITY LOW MESSAGE. MAINTENANCE FOUND THE LEFT SYSTEM ACCUMULATOR LEAKING (N947AT)
- [SDR ABXA20260628289](https://openairdocs.org/sdr/ABXA20260628289), Jun 28, 2026: Boeing 767316. MODULE. DEFECTIVE. DURING TAXI, CENTER HYD SYSTEM PRESSURE 1070 PSI WITH BOTH ENGINES RUNNING, A/C RETURNED TO GATE (BTB) AND MTX GROUNDED  (N227CY)
- [SDR YENA2026051200452](https://openairdocs.org/sdr/YENA2026051200452), May 7, 2026: Airbus A321271NX. SWIVEL. LEAKING. FLT 1515, JFK-SFO(ETOPS)(AIR TURNBACK TO JFK). REC "D HYD G ENG 1 PUMP LO PR" ECAM UPON LANDING GEAR RETRACTION. FOLLOWE (N2193J)
- [SDR R61A2026042410109](https://openairdocs.org/sdr/R61A2026042410109), Apr 21, 2026: Emb ERJ170200LR. RESERVOIR. FAULTED. HYD 1 LO QTY. DECLARED EMERGENCY, LANDED WITHOUT INCIDENT. REMOVED AND REPLACED HYD SYS #1 RESERVIOR. (N753YX)
- [SDR CALA2026032414817](https://openairdocs.org/sdr/CALA2026032414817), Mar 22, 2026: Airbus A320232. B-NUT. LEAKING. CREW REPORTED HYD G RSVR LO LEVEL CREW REPORTED THAT THEY TURNED OFF THE PTU AND THE ENG DRIVEN PUMPP WITHIN A MIN OF TH (N470UA)
- [SDR AALA202601290661](https://openairdocs.org/sdr/AALA202601290661), Jan 22, 2026: Boeing 737823. FILTER. CONTAMINATED. AIRCRAFT WAS GROUNDED: AN EMERGENCY WAS DECLARED DUE TO: AT CRUISE ALTITUDE ENGINE #2 HYDRAULIC PRESSURE LOW LIGHT ILLUM (N927AN)
- [SDR AALA202601294037](https://openairdocs.org/sdr/AALA202601294037), Jan 22, 2026: Boeing 737823. FILTER. CONTAMINATED. AIRCRAFT WAS GROUNDED: AN EMERGENCY WAS DECLARED DUE TO: AT CRUISE ALTITUDE ENGINE #2 HYDRAULIC PRESSURE LOW LIGHT ILLUM (N927AN)
- [SDR AALA202601291379](https://openairdocs.org/sdr/AALA202601291379), Jan 22, 2026: Boeing 737823. FILTER. CONTAMINATED. AIRCRAFT WAS GROUNDED: AN EMERGENCY WAS DECLARED DUE TO: AT CRUISE ALTITUDE ENGINE #2 HYDRAULIC PRESSURE LOW LIGHT ILLUM (N927AN)
- [SDR AALA202601297620](https://openairdocs.org/sdr/AALA202601297620), Jan 22, 2026: Boeing 737823. HYDRAULIC SYSTEM. FAILED. AIRCRAFT WAS GROUNDED: AN EMERGENCY WAS DECLARED DUE TO: AT CRUISE ALTITUDE ENGINE #2 HYDRAULIC PRESSURE LOW LIGHT ILLUM (N927AN)
- [SDR SWAA2025032007748](https://openairdocs.org/sdr/SWAA2025032007748), Mar 18, 2025: Boeing 7377Q8. MODULE. LOW PRESSURE. AFTER FLAPS 5 HYD A SYSTEM LOOW PRESSURE LIGHTS ON BOTH ENG AND ELECTRIC PUMP SHORTLY AFTER LOW PRESSURE LIGHTS ON HYD S (N7876A)
- [SDR SWAA2025031204529](https://openairdocs.org/sdr/SWAA2025031204529), Mar 12, 2025: Boeing 7377H4. B-NUT. LOOSE. EVIDENCE OF HYDRAULIC LEAK IN HELL HOLE <[01]. PERFORMED INSPECTION IN THE HELL HOLE FOUND HYDRAULIC LEAK FROM ELEVATOR  (N209WN)
- [SDR CALA2025021002254](https://openairdocs.org/sdr/CALA2025021002254), Feb 8, 2025: Airbus A319131. ACCUMULATOR. FAULTED. HYD G RSVR LO LVL INFLIGHT DEBRIEFED WITH THE PILOTS. THERE WAS A HYD G RSVR LO LVL ECAM MSG. THEY STATED THE RESERVOIR  (N809UA)
- [SDR IPXA2024110545086](https://openairdocs.org/sdr/IPXA2024110545086), Nov 2, 2024: Airbus A300F4622R. RESERVOIR. INOPERATIVE. GREEN RSVR LO LEVEL. GREEN SYSTEM SHOWED LOW INFLIGHT. REF BARCODE T3F18E005HJ2D FOR R&R OF THE GREEN SYSTEM HYDRAULIC R (N161UP)
- [SDR 2024FA0000455](https://openairdocs.org/sdr/2024FA0000455), Jun 18, 2024: Piper PA44180. RESERVOIR. LEAKING. HYDRAULIC POWER PACK SEVERE LEAK FROM RESERVOIR, PIPER PART NUMBER 601-940, GARKENYON PART NUMBER BELOW. (N221FL)
- [SDR 2024FA0000454](https://openairdocs.org/sdr/2024FA0000454), Jun 18, 2024: Piper PA44180. RESERVOIR. LEAKING. HYDRAULIC POWER PACK SEVERE LEAK FROM RESERVOIR, PIPER PART NUMBER 601-940, (N221FL)
- [SDR CALA2024012300204](https://openairdocs.org/sdr/CALA2024012300204), Jan 16, 2024: Airbus A320232. ACCUMULATOR. LEAKING. BLUE SYSTEM LOST HYD FLUID IN FLIGHT BOTTOM OF AIRCRAFT WET WITH HYD FLUID. ACCUMULATOR, HY OFF 31-2912-9-9001 7440 ON 0 (N492UA)
- [SDR SWAA2023081489219](https://openairdocs.org/sdr/SWAA2023081489219), Aug 14, 2023: Boeing 7377H4. LIMITER. CRACKED. LOSS OF HYD B ON DEP. RAN CHECKLIST; TURN OFF B-PUMP IN UNDER A MIN. QTY WAS ZERO<[01] FOUND LEAK ON SYS B HYD FLOW LIMI (N465WN)
- [SDR SWAA2023071076920](https://openairdocs.org/sdr/SWAA2023071076920), Jul 8, 2023: Boeing 7377H4. FILTER. FAILED. B HYD SYSTEM FAILURE<[01] REMOVED AND REPLACED #2 ENGINE DRIVE HYDRAULIC PUMP IAW MM 29-11-11<BR>REMOVED AND REPLACED B  (N925WN)
- [SDR SWAA2023071076921](https://openairdocs.org/sdr/SWAA2023071076921), Jul 8, 2023: Boeing 7377H4. FUSE. FAILED. B HYD SYSTEM FAILURE<[01] REMOVED AND REPLACED #2 ENGINE DRIVE HYDRAULIC PUMP IAW MM 29-11-11<BR>REMOVED AND REPLACED B  (N925WN)
- [SDR SWAA2023070372956](https://openairdocs.org/sdr/SWAA2023070372956), Jun 29, 2023: Boeing 7377BD. PUMP. LEAKING. ENROUTE; F/A'S REPORTED A STRONG UNIDENTIFIABLE ODOR THROUGHOUT THE ENTIRE CABIN. ODOR LASTED FOR ONLY A COUPLE OF MINUE (N7720F)
- [SDR ABXA20230627138](https://openairdocs.org/sdr/ABXA20230627138), Jun 26, 2023: Boeing 767338. UNKNOWN. UNKNOWN. C HYD PRIM 1 EICAS MESSAGE DURING TAXI. AIRCRAFT BACK TO BLOCK AND GROUNDED BY MAINTENANCE. MAINTENANCE PERFORMED A VISU (N364CM)
- [SDR ABXA2023031434](https://openairdocs.org/sdr/ABXA2023031434), Mar 13, 2023: Boeing 767232. UNKNOWN. UNKNOWN. EICAS MESSAGE C HYD PRIM 1 ON TAXI OUT. AIRCRAFT BACK TO BLOCK AND GROUNDED BY MAINTENANCE. MAINTENANCE PERFORMED OPERAT (N744AX)
- [SDR SWAA2023021302237](https://openairdocs.org/sdr/SWAA2023021302237), Feb 11, 2023: Boeing 7377H4. PUMP. LEAKING. LOSS OF HYDRAULIC B ON FINAL; EMERGENCY DECLARED.<[01] REMOVED AND REPLACED #5 FLIGHT SPOILER DUE TO LEAKING IAW AMM 27- (N940WN)
- [SDR SWAA2023021302238](https://openairdocs.org/sdr/SWAA2023021302238), Feb 11, 2023: Boeing 7377H4. PUMP. LEAKING. LOSS OF HYDRAULIC B ON FINAL; EMERGENCY DECLARED.<[01] REMOVED AND REPLACED #5 FLIGHT SPOILER DUE TO LEAKING IAW AMM 27- (N940WN)
- [SDR SWAA2023021302239](https://openairdocs.org/sdr/SWAA2023021302239), Feb 11, 2023: Boeing 7377H4. FILTER. LEAKING. LOSS OF HYDRAULIC B ON FINAL; EMERGENCY DECLARED.<[01] REMOVED AND REPLACED #5 FLIGHT SPOILER DUE TO LEAKING IAW AMM 27- (N940WN)
- [SDR YENA2023020300131](https://openairdocs.org/sdr/YENA2023020300131), Feb 1, 2023: Airbus A321271N. PUMP. FAILED. FLT#988, LAX-BOS. (ETOPS) 'ENG 1 EDP LEAKING; REMOVED AND REPLACED ENG 1 EDP. REF AMM 29-11-51. OPS 1 LEAK CHECK IS GOOD (N2142J)
- [SDR CALA2023020100275](https://openairdocs.org/sdr/CALA2023020100275), Jan 31, 2023: Airbus A320232. NONE. NONE. GRN HYD LOW PRESSURE WITH 0 QTY AND AMBER INDICATION..FOLLOWED ECAM DECLARED EMER. COMPLETED INSTALLATION OF HCU REF AMM (N407UA)
- [SDR VNAA202301111111](https://openairdocs.org/sdr/VNAA202301111111), Jan 9, 2023: Cndair CL6002D24. TRANSDUCER. LEAKING. HYD SYS 2 LO PRESS IN FLT, INBD FLT SPOILER/SPLRONS / AFTER INSPECTION FOUND HYD SYS 2 PRESSURE MANIFOLD TRANSDUCER TO B (N553NN)
- [SDR FDEA202212293032](https://openairdocs.org/sdr/FDEA202212293032), Dec 29, 2022: Airbus A300F4605R. PUMP. UNKNOWN. LOSS OF BLUE HYDRAULIC SYSTEM IN CRUISE. FACT 29DEC22 16:24 MEM U AMM: 29-11-32-04-02 AMM: 29-11-36-04-02 AMM: 29-11-42- (N690FE)
- [SDR 7C7A2022122000042](https://openairdocs.org/sdr/7C7A2022122000042), Dec 20, 2022: Dhav DHC8106. SPU. FAILED. NO.2 STBY HYDRAULIC PRESSURE INDICATES ZERO WHEN ON. NO ASSOCIATED CAUTION LIGHTS. REPLACED #2 STANDBY POWER UNIT (N885EA)
- [SDR CALA2022112503232](https://openairdocs.org/sdr/CALA2022112503232), Nov 25, 2022: Airbus A320232. ACCUMULATOR. LEAKING. HYD G RSVR LO LVL IN CRUSE FL380ECAM COMPLETE FOUND GREEN POWER ACCUMULATOR LEAKING AT UPPER CONNECTION. COMPLETED INSTA (N444UA)
- [SDR CALA2022112103191](https://openairdocs.org/sdr/CALA2022112103191), Nov 21, 2022: Boeing 737924ER. PUMP. FAILED. COMPLETE LOSS OF SYS B HYD ON ARRIVAL QUANTITY AT ZERO ENGINE DRIVEN PUMP SERVICED B SYSTEM IN ORDER TO RETRACT FLAPS/SL (N34460)
- [SDR GTIA2022112136789](https://openairdocs.org/sdr/GTIA2022112136789), Nov 19, 2022: Airbus A320271N. HYDRAULIC SYSTEM. LOW PRESSURE. COMPLETE LOSS OF GREEN HYD SYSTEM AT CRUISE. HYD G ENG 1 PUMP LO PR ECAM-- (N916NK)
- [SDR CALA2022111703163](https://openairdocs.org/sdr/CALA2022111703163), Nov 17, 2022: Boeing 757224. LINE. LOOSE. C HYD QTY STATUS MSG AT FL370 1 HOUR FROM LAN DING. FOLLOWED CHC KLIST ISOLATED SYS. .43 RF FOUND RETURN LINE BETWEEN RT (N67134)
- [SDR GTIA2022111436777](https://openairdocs.org/sdr/GTIA2022111436777), Nov 12, 2022: Airbus A320271N. ACCUMULATOR. LEAKING. HYD G RSV LO LVL IN FLIGHT-PERFORMED PRESSRIZATION OF GREEN HYD SYSTEM IAW AMM 29-23-00. FOUND LEAK FROM GREEN POWER ACC (N952NK)
- [SDR YENA2022110201083](https://openairdocs.org/sdr/YENA2022110201083), Oct 28, 2022: Airbus A320232. NONE. NONE. FLT#1826, SAT-JFK. (AIRCRAFT DECLARED AN EMERGENCY INTO JFK) 'HYDRAULIC GREEN LOW-LEVEL RESERVOIR ECAM DURING CRUISE IND (N556JB)
- [SDR CALA2022100302634](https://openairdocs.org/sdr/CALA2022100302634), Oct 3, 2022: Boeing 737824. PUMP. FAULTY. ENG 1 ENGINE HYD PUMP LOW PRESSURE LIGHT ILLUMINATED INFLIGHT. FLUID DOWN TO 20. INSTALLED #1 ENGINE HYD PUMP, LEAK COMP (N12218)
- [SDR YENA2022092300949](https://openairdocs.org/sdr/YENA2022092300949), Sep 22, 2022: Airbus A320232. NONE. NONE. FLT#76, MSY-JFK. (AIRCRAFT DECLARED A EMERGENCY INTO JFK) 'ECAM G RSVR LO LVL. SO WE HAD A TOTAL LOSS OF GREEN SYS HYD.  (N708JB)
- [SDR SCNA20220920108](https://openairdocs.org/sdr/SCNA20220920108), Sep 16, 2022: Boeing 73783N. NONE. NONE. DEFECT 725253: LOSS OF SYSTEM B HYDRAULIS IN FLIGHT. RESOLUTION: FOUND PLUG ON B SYSTEM HYD MODULE TO BE LOOSE TIGHTENED (N831SY)
- [SDR CALA2022090502272](https://openairdocs.org/sdr/CALA2022090502272), Sep 5, 2022: Boeing 737. NONE. DAMAGED. FOUND #2 ENGINE HYDRAULIC LINE PRESSURE( SMALLER OF THE 2) LINE SPINS GOING INTO PYLON FOUND QUICK DISCONNECT AT PYLON W (N37409)
- [SDR UIEA2022080500815](https://openairdocs.org/sdr/UIEA2022080500815), Aug 4, 2022: Boeing 74747UF. PRESSURE SYSTEM. LOW PRESSURE. AFTER T/O "HYD QTY 1" EICAS MSG, SHORTLY AFTER "HYD SYS 1"(<P>FOUND #1 ADP PRESSURE HOSE LEAKING. R/R #1 ADP PRESSURE HO (N492MC)
- [SDR AALA202207158364](https://openairdocs.org/sdr/AALA202207158364), Jul 14, 2022: Airbus A319112. ACCUMULATOR. LEAKING. AIRCRAFT WAS GROUNDED: YELLOW HYDRAULIC SYSTEM RESERVOIR LOW LEVEL ECAM AND SUBSEQUENT SPOILER FAULT IN FLIGHT NO FLUID  (N764US)
- [SDR UIEA2022070100707](https://openairdocs.org/sdr/UIEA2022070100707), Jul 13, 2022: Boeing 767306. ACTUATOR. LEAKING. RH WING, INBOARD AILERON, ACTUATORS, LEAK EVIDENCE (LEAK CHECK HAS BEEN PERFORMED ON THE RH INBOARD AILERON ACTUATORS AN (N1427A)
- [SDR CALA2022071301726](https://openairdocs.org/sdr/CALA2022071301726), Jul 13, 2022: Boeing 7878. PUMP. INOPERATIVE. HYD PRESS SYS C CAUTION IF RESERVE STEERING ISOLATION VALVE IS IN THE NORMAL FLIGHT POSI TION, THEN THE MESSAGE APPEARS  (N28912)
- [SDR ABXA2022070876](https://openairdocs.org/sdr/ABXA2022070876), Jul 8, 2022: Boeing 767. NONE. NONE. LEFT HYDRAULIC PRIMARY PUMP APPEARS INOP. AIRCRAFT RETURNED TO GATE AND WAS GROUNDED BY MAINTENANCE. MAINTENANCE REPLACE (N371CM)
- [SDR CALA2022070601648](https://openairdocs.org/sdr/CALA2022070601648), Jul 6, 2022: Airbus A300*. NONE. FAILED. TOTAL LOSS OF GREEN HYD SYS, #1 ENGINE DRIVEN HYD PUMP REQUIRES REPLACEMENT. REPLACED HYD PUMP . STOPPED AT STEP CORRECT (N423UA)
- [SDR CALA2022062201554](https://openairdocs.org/sdr/CALA2022062201554), Jun 22, 2022: Airbus A320232. SAFETY VALVE. LEAKING. LOSS OF GREEN HYDS, HYD G RSVR LO LVL, HYD G SYS LO PR AND HYD G ENG 1 PUMP LO PR. LOCKING FOR POSITIVE FIX. UNLOCK TO U (N482UA)
- [SDR I5PA2022062068806](https://openairdocs.org/sdr/I5PA2022062068806), Jun 20, 2022: Boeing 757230. PUMP. LEAKING. FOUND HYD. LEAK AT L ENG EDP... R/R L ENG EDP PER AMM 29-11-05. ENG RUN NORMAL NO LEAKS FOUND. (N688SL)

All 202: https://openairdocs.org/jasc/2911/reports.md

## Other codes in chapter 29

- [JASC 2900](https://openairdocs.org/jasc/2900): Hydraulic Power System (333 reports)
- [JASC 2910](https://openairdocs.org/jasc/2910): Hydraulic System, Main (11,280 reports)
- [JASC 2912](https://openairdocs.org/jasc/2912): Hydraulic Filter, Main (201 reports)
- [JASC 2913](https://openairdocs.org/jasc/2913): Hydraulic Pump (Electric/Engine), Main (4,062 reports)
- [JASC 2914](https://openairdocs.org/jasc/2914): Hydraulic Handpump, Main (22 reports)
- [JASC 2915](https://openairdocs.org/jasc/2915): Hydraulic Pressure Relief Valve, Main (101 reports)
- [JASC 2916](https://openairdocs.org/jasc/2916): Hydraulic Reservoir, Main (385 reports)
- [JASC 2917](https://openairdocs.org/jasc/2917): Hydraulic Pressure Regulator, Main (65 reports)
- [JASC 2920](https://openairdocs.org/jasc/2920): Hydraulic System, Auxiliary (287 reports)
- [JASC 2921](https://openairdocs.org/jasc/2921): Hydraulic Accumulator, Auxiliary (42 reports)
- [JASC 2922](https://openairdocs.org/jasc/2922): Hydraulic Filter, Auxiliary (20 reports)
- [JASC 2923](https://openairdocs.org/jasc/2923): Hydraulic Pump, Auxiliary (138 reports)
- [JASC 2925](https://openairdocs.org/jasc/2925): Hydraulic Pressure Relief, Auxiliary (4 reports)
- [JASC 2926](https://openairdocs.org/jasc/2926): Hydraulic Reservoir, Auxiliary (14 reports)
- [JASC 2927](https://openairdocs.org/jasc/2927): Hydraulic Pressure Regulator, Auxiliary (8 reports)
- [JASC 2930](https://openairdocs.org/jasc/2930): Hydraulic Indicating System (549 reports)
- [JASC 2931](https://openairdocs.org/jasc/2931): Hydraulic Pressure Indicator (160 reports)
- [JASC 2932](https://openairdocs.org/jasc/2932): Hydraulic Pressure Sensor (290 reports)
- [JASC 2933](https://openairdocs.org/jasc/2933): Hydraulic Quantity Indicator (121 reports)
- [JASC 2934](https://openairdocs.org/jasc/2934): Hydraulic Quantity Sensor (96 reports)
- [JASC 2997](https://openairdocs.org/jasc/2997): Hydraulic Power System Wiring (343 reports)

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