# JASC 3243: Master Cylinder/Brake Valve

- Type: JASC system/component code (FAA)
- ATA chapter: 32 Landing Gear
- Title in the code table: MASTER CYLINDER/BRAKE VALVE
- Service difficulty reports: 445
- FAA code table: https://www.faa.gov/sites/faa.gov/files/JASC_Code.pdf#page=34
- Page: https://openairdocs.org/jasc/3243

## What it covers

The units that provide a power source for cylinder-power brake actuation. Does not include connecting lines to brake units, which are filed in JASC code 3240. Typical parts are seal, piston, housing, etc.

## Service difficulty reports (445, newest 50)

- [SDR AALA202610101350](https://openairdocs.org/sdr/AALA202610101350), Oct 5, 2026: Airbus A319132. MASTER CYLINDER. DEFECTIVE. AIRCRAFT WAS GROUNDED: RIGHT BRAKE UNABLE TO MODULATE BRAKING PRESSURE, RIGHT BRAKE PEDAL HAS LITTLE OR NO FEEDBACK - MA (N839AW)
- [SDR COEA2026082705738](https://openairdocs.org/sdr/COEA2026082705738), Aug 26, 2026: Textrn 408. MASTER CYLINDER. FAILED. FLIGHT 7804, PILOT SIDE RIGHT BRAKE PEDAL INEFFECTIVE. REPLACED ALL 4 MASTER CYLINDERS AND RT BRAKE ASSEMBLY. FLUSHED EN (N738FX)
- [SDR 37CA2026070900144](https://openairdocs.org/sdr/37CA2026070900144), Jul 9, 2026: Agusta AW119MKII. SKID. CORRODED. CORROSION WAS IDENTIFIED IN THE SKID TUBE BUSHING AREA WHERE SKID SHOE THROUGH BOLTS ATTACH. (N352LL)
- [SDR ELYA20250804004](https://openairdocs.org/sdr/ELYA20250804004), Aug 4, 2025: Tecnam P2012. MASTER CYLINDER. BYPASSING. COMPLETE LOSS OF LEFT BRAKE. REMOVED AND REPLACED MASTER CYLINDER. (N244US)
- [SDR DALA2025062304667](https://openairdocs.org/sdr/DALA2025062304667), Jun 22, 2025: Airbus A320212. FITTING. SHEARED. SHIP 3236 - MISC/DE - DUE TO L/G DOORS NOT CLOSED ECAM WARNING AT GEAR EXTENSION. FOUND LH FORWARD GEAR DOOR ACTUATOR FI (N336NW)
- [SDR AALA202503234383](https://openairdocs.org/sdr/AALA202503234383), Mar 21, 2025: Airbus A321211. MASTER CYLINDER. LOW PRESSURE. AIRCRAFT WAS GROUNDED: AFTER AUTOBRAKES DISENGAGED, LEFT BRAKE PEDAL DEFLECTION FOR FIRST 3" OF TRAVEL, DOES NOT PRODUCE (N187US)
- [SDR AALA202409108825](https://openairdocs.org/sdr/AALA202409108825), Aug 27, 2024: Airbus A320232. MASTER CYLINDER. LEAKING. AIRCRAFT WAS GROUNDED: UPON LANDING LEFT BRAKES GRABBED HARD, RIGHT BRAKES PUSHED TO FLOOR FOR BRAKE APPLICATION. TAXI I (N655AW)
- [SDR AALA202409106689](https://openairdocs.org/sdr/AALA202409106689), Aug 27, 2024: Airbus A320232. MASTER CYLINDER. LEAKING. AIRCRAFT WAS GROUNDED: UPON LANDING LEFT BRAKES GRABBED HARD, RIGHT BRAKES PUSHED TO FLOOR FOR BRAKE APPLICATION. TAXI I (N655AW)
- [SDR AALA202407088714](https://openairdocs.org/sdr/AALA202407088714), Jul 5, 2024: Airbus A320214. MASTER CYLINDER. LEAKING. AIRCRAFT WAS GROUNDED: FLIGHT CREW REPORTED THAT THE RIGHT BRAKE PEDAL HAS 1-2 INCHES OF TRAVEL BEFORE ENGAGING. MAINTEN (N110UW)
- [SDR SWAA2024062003261](https://openairdocs.org/sdr/SWAA2024062003261), Jun 18, 2024: Boeing 73779P. WHEEL. ABNORMAL. AFTER LANDING AT TAXI. SPEED FELT SLIGHT SHIMMY FROM NOSE WHEEL AND TOWER REPORTED SMALL AMOUNT OF SMOKE FROM FRONT OF A (N7869A)
- [SDR AALA202406205113](https://openairdocs.org/sdr/AALA202406205113), Jun 18, 2024: Airbus A319112. MASTER CYLINDER. LEAKING. AIRCRAFT WAS GROUNDED: FLIGHT CREW REPORTED WHEEL BRAKE VIBRATION ON LANDING ROLLOUT STARTING APPROXIMATELY 60 KNOTS TO  (N709UW)
- [SDR 141A2024040200002](https://openairdocs.org/sdr/141A2024040200002), Mar 29, 2024: Cessna 208B. MASTER CYLINDER. DEFECTIVE. LEFT HAND BRAKE INEFFECTIVE. MAINTENANCE REPLACED LEFT HAND MASTER CYLINDER. PERFORMED HIGH SPEED TAXI. OPS CHECKED GOOD (N1258B)
- [SDR SWIA20231120](https://openairdocs.org/sdr/SWIA20231120), Nov 20, 2023: Cndair CL6002C10. UNKNOWN. WARNING MESSAGE. MLG OVERHEAT WARNING MESSAGE DURING DESCENT. EVERY TIME WE RESET THE MASTER WARNING, IT WOULD GO OFF AGAIN. FOLLOWED QRH (N708EV)
- [SDR ENHA202310251716](https://openairdocs.org/sdr/ENHA202310251716), Oct 24, 2023: Cessna 208B. BRAKE SYS. FAULTY. RIGHT BRAKE MUSHY- AT TIMES NON-RESPONSIVE BRAKE ON RIGHT MAIN GEAR-YAWS PLANE TO THE LEFT ON TAXI (N9539F)
- [SDR FDEA202310101738](https://openairdocs.org/sdr/FDEA202310101738), Oct 10, 2023: Boeing 767300. BRAKE. FAILED. UPON GEAR RETRACTION ON TAKEOFF IN IND WE GOT A BRAKE TEMP LIGHT ON CLIMB OUT. THE #6 BRAKE CONTINUED TO CLIMB AND PEAKE (N188FE)
- [SDR YADA2023092101](https://openairdocs.org/sdr/YADA2023092101), Sep 21, 2023: Beech 1900C. MASTER CYLINDER. FAILED. PILOT REPORTED AFTER LANDING AND DURING TAXI "PILOT SIDE LEFT BRAKE GOES FLAT". MAINTENANCE PERFORMED TROUBLESHOOTING AN (N113AX)
- [SDR KCQA202306050504](https://openairdocs.org/sdr/KCQA202306050504), Jun 4, 2023: Beech 99A. HOSE. LEAKING. PILOT RH HAND BRAKE INOPERATIVE. ON WO# 000101 DATED 06/05/2023 FOUND EMPTY BRAKE RESERVOIR. INSPECTED BRAKE PLUMBING AN (N499CZ)
- [SDR SIMA20230414001](https://openairdocs.org/sdr/SIMA20230414001), Apr 14, 2023: Emb ERJ170200LR. UNKNOWN. UNKNOWN. RIGHT MAIN LANDING GEAR WHEEL WELL ELECTRIC FUMES/ ACID ODOR ALSO LIQUID SPILL/ HIDRAULICS-C/A-RESECURED HYD LINE ON #1  (N279MQ)
- [SDR UOIA2023041200006](https://openairdocs.org/sdr/UOIA2023041200006), Apr 12, 2023: Bnorm BN2A8. MASTER CYLINDER. BLOCKED. AFTER LANDING LOSS BRAKE ACTION. (N903GD)
- [SDR IPXA2023040392540](https://openairdocs.org/sdr/IPXA2023040392540), Apr 3, 2023: Boeing 76734AF. ANTI-SKID SYS. WARNING MESSAGE. ANTISKID INOP EICAS MSG QRH PROCEDURE ACCOMPLISHED. ANTISKID/AUTOBRAKE CONTROL UNIT SHOWS VLV 7 NIL TIME OR PARTS AT EMA (N328UP)
- [SDR 2023FA0000181](https://openairdocs.org/sdr/2023FA0000181), Mar 27, 2023: Bombdr BD7001A11. UNKNOWN. UNKNOWN. CREW REPORTED ON APPROACH 6 INTO KTEB, PRIOR TO FAF, AMBER BRAKE 50% DEGRADED CAS MESSAGE POSTED. EXECUTED GO-AROUND, WI (N500VJ)
- [SDR IPXA2023030491510](https://openairdocs.org/sdr/IPXA2023030491510), Mar 3, 2023: Boeing 76734AF. NONE. INOPERATIVE. INSPECTION TYPE:NAON LANDING ROLL AUTO BRAKES DID NOT DISENGAGE BY USING THE SPEED BREAK LEVERPERFORMED OPERATIONAL TEST (N307UP)
- [SDR SWIA20230223](https://openairdocs.org/sdr/SWIA20230223), Feb 23, 2023: Cndair CL6002B19. UNKNOWN. CRACKED. IN RH W/W, BRAKE PRESSURE TRANDUCER'S FWD HYD LINE MOUNTING BRACKET IS CRACKED (MARKED). (C-CHECK RO 4/5/2023) REPLACED  (N900EV)
- [SDR MTNA20230127001](https://openairdocs.org/sdr/MTNA20230127001), Jan 27, 2023: Aerosp ATR72212. MASTER CYLINDER. FAULTED. ON TAXI TO RAMP IT WAS OBSERVED THE CAPTAINS RIGHT SIDE BRAKE WAS INEFFECTIVE. REPLACED CAPTAINS BRAKE MASTER CYLINDER.  (N806FX)
- [SDR SWIA202266739](https://openairdocs.org/sdr/SWIA202266739), Nov 8, 2022: Cndair CL6002C10. NONE. OVERHEATED. BRAKE OVER HEAT MASTER WARNING IN DECENT. COME ON SHOWED 12 ON RIGHT INBOARD THE WENT TO 0, WENT AWAY. CAME BACK ON AT 2 (N744EV)
- [SDR 2022FA0000662](https://openairdocs.org/sdr/2022FA0000662), Nov 1, 2022: Piper PA28161. MASTER CYLINDER. DETACHED. PILOT R/H MASTER CYLINDER PISTON CAME OUT OF HOUSING WHEN PARKING BRAKE WAS APPLIED. THIS CAUSING THE RUDDER PEDAL TO FA (N685ND)
- [SDR 2022FA0000661](https://openairdocs.org/sdr/2022FA0000661), Nov 1, 2022: Piper PA28161. MASTER CYLINDER. DETACHED. CO-PILOT L/H MASTER CYLINDER PISTON PULLED OUT OF HOUSING WHEN PARKING BRAKE APPLIED. CAUSING THE L/H RUDDER PEDAL TO FA (N706ND)
- [SDR YENA2022110101050](https://openairdocs.org/sdr/YENA2022110101050), Oct 31, 2022: Airbus A320232. NONE. FAILED. FLT# 8598, VQQ-FLL. BRAKES ALTERNATE (R) RELEASE ECAM MSG, AFTER GEAR DOWN, WENT AROUND MAINT SAID TO CYCLE A/SKID NW SW (N809JB)
- [SDR WX0A1900010074286](https://openairdocs.org/sdr/WX0A1900010074286), Oct 17, 2022: Airbus A319111. SERVO VALVE. FAULTY. (EMERGENCY DECLARED) AFTER SELECTING GEAR DOWN RECEIVED BRAKES ALTN R RELEASED, ECAM MESSAGE ""ALTN R BRK"" WAS DISPLAYE (N326NV)
- [SDR 2022FA0000535](https://openairdocs.org/sdr/2022FA0000535), Sep 20, 2022: Cessna 172D. PISTON ROD. BROKEN. THE THREADED END OF THE RIGHT BRAKE MASTER CYLINDER PISTON ROD SNAPPED OFF WHILE BLEEDING THE BRAKES. THE SEATS WERE OUT (N2385U)
- [SDR IPXA2022052382383](https://openairdocs.org/sdr/IPXA2022052382383), May 20, 2022: Boeing 75724APF. ANTI-SKID SYS. WARNING MESSAGE. **EMERGENCY DECLARED** **NORMAL LANDING** DURING CRUISE-EICAS ANTI SKID ILLUMINATED RAN QRH-NO CHANGE. DMP COMPLIED WITH (N454UP)
- [SDR GTIA2022051636424](https://openairdocs.org/sdr/GTIA2022051636424), May 12, 2022: Airbus A320232. NONE. FAULT MESSAGE. DURING APPROACH KSNA SELECTING GEAR DOWN, ECAM CAUTION BRAKE ALT BRK FAULT WHEEL SYST PAGE WAS NORMAL, HYD PRESS NORMAL  (N630NK)
- [SDR IPXA2022041481168](https://openairdocs.org/sdr/IPXA2022041481168), Apr 14, 2022: Doug MD11F. NONE. FAILED. INSPECTION TYPE:NA**EMERG DECLARED** ANTI SKIDE R FAIL DURING FIRST APPROACH WENT AROUND AND ACCOMPLISH QRH PROCEDURE 2N (N279UP)
- [SDR FDEA202204050873](https://openairdocs.org/sdr/FDEA202204050873), Apr 5, 2022: Doug MD11F. BRAKE. DAMAGED. BRAKE OVERHEAT ON TAXI OUT. NUMBER 5 BRAKE GOT TO 710. AIRCRAFT STOPPED AND WHILE STOPPED THE FUSE PLUG BLEW AND PRESSUR (N596FE)
- [SDR YENA2022031400176](https://openairdocs.org/sdr/YENA2022031400176), Mar 13, 2022: Airbus A320232. ACCUMULATOR. UNDERSERVICED. FLT#2736, LAX-SFO. 'ALTERNATE BRAKE SYSTEM TEST FAILED ( BRAKE PRESSURE 1000 PSI AND ACCUMULATOR NEAR 0); FOUND BRAKE AC (N594JB)
- [SDR MTNA20220312001](https://openairdocs.org/sdr/MTNA20220312001), Mar 12, 2022: Aerosp ATR42*. MASTER CYLINDER. WEAK. FO'S RIGHT BRAKE PEDAL WEAK IN EFFECTIVENESS. REMOVED AND REPLACED FO MASTER BRAKE CYLINDER. OPS AND LEAK CHECK GOOD. (N906FX)
- [SDR YADA2021123101](https://openairdocs.org/sdr/YADA2021123101), Dec 31, 2021: Beech 1900C. NONE. NONE. PILOT REPORT - CAPTAINS LEFT BRAKE PEDAL LOOSES PRESSURE AND GOES TO FLOOR - NO BRAKE. MAINTENANCE REPLACED THE CAPTAINS (N124AX)
- [SDR SIMA20210922001](https://openairdocs.org/sdr/SIMA20210922001), Sep 22, 2021: Emb ERJ170200LR. NONE. NONE. ENROUTE HAD BRAKE LIGHT ON ?IN FLT. EMERGENCY DECLARED - IN CLIMBOUT PRKG BRK NOT RELEASED CAUTION STAYED ON UNTIL AFTER (N212NN)
- [SDR AALA202109214315](https://openairdocs.org/sdr/AALA202109214315), Sep 19, 2021: Boeing 737823. SWITCH. FAILED. AIRCRAFT WAS GROUNDED: AUTO BRAKE FAILED UPON LANDING AUTO BRAKE DISARM LIGHT EXTINGUISHED IN OFF POSITION. REMOVED AND  (N987AN)
- [SDR HYIA20210525001](https://openairdocs.org/sdr/HYIA20210525001), May 19, 2021: Cessna 402C. MASTER CYLINDER. FAULTED. THE PILOT A LOSS OF PRESSURE ON THE RIGHT BRAKE DURING PARKING. MAINTENANCE INSPECTED AND FOUND THE RIGHT MASTER CYLINDE (N67886)
- [SDR MTNA20210326001](https://openairdocs.org/sdr/MTNA20210326001), Mar 25, 2021: Cessna 208B. MASTER CYLINDER. INOPERATIVE. PILOT REPORTED RIGHT HAND BRAKE SOFT. REMOVED AND REPLACED RIGHT BRAKE MASTER CYLINDER. OPS CHECK GOOD. (N869FE)
- [SDR COEA2020070704946](https://openairdocs.org/sdr/COEA2020070704946), Jul 6, 2020: Cessna 208B. MASTER CYLINDER. FAILED. FLIGHT 7770, LEFT BRAKE HAD NO BRAKING ACTION, PEDAL GOES TO THE FLOOR. MAINTENANCE REPLACED THE BRAKE MASTER CYLINDER.  (N946FX)
- [SDR 2020FA0000287](https://openairdocs.org/sdr/2020FA0000287), Jun 5, 2020: Cessna 208B. NUT. LOOSE. LEFT BRAKE PEDAL DID NOT PROPERLY ACTUATE BRAKES. PEDAL WAS SOFT AND APPLIED LITTLE TO NO BRAKING ACTION ON LEFT BRAKE.  (N208CE)
- [SDR O2GA2020032001](https://openairdocs.org/sdr/O2GA2020032001), Mar 14, 2020: Beech B300. MASTER CYLINDER. LEAKING. THE CREW EXPERIENCED A LEFT MAIN LANDING GEAR BRAKE ISSUE DURING TAXI. POST INSPECTION LEFT MAIN TIRES WERE FLAT SPOTTED (N868UP)
- [SDR 5JGA2020030600000](https://openairdocs.org/sdr/5JGA2020030600000), Mar 6, 2020: Piper PA31P350. MASTER CYLINDER. FAILED. THE PILOT EXPERIENCED A TOTAL FAILURE OF THE LEFT BRAKE SYSTEM DURING LANDING, NO EXTERNAL LEAKS WERE DETECTED FOLLOWING (N9202Y)
- [SDR AALA202001149014](https://openairdocs.org/sdr/AALA202001149014), Jan 13, 2020: Airbus A320232. MASTER CYLINDER. DEFECTIVE. AIRCRAFT WAS GROUNDED: CAPT LEFT BRAKE PEDAL FEELS SPONGY. REMOVED AND REPLACED LEFT BRAKE CONTROL MASTER CYLINDER IAW A (N661AW)
- [SDR SWIA2020021448453](https://openairdocs.org/sdr/SWIA2020021448453), Dec 29, 2019: Cndair CL6002B19. ATTACH BRACKET. CRACKED. LH MLG W/W HYDRAULIC PRESSURE TRANSDUCER ATTACH BRACKET AT LWR SURFACE OF PRESSURE FLOOR SKIN, BROKEN. (C-CHECK) RO 2/10 (N978SW)
- [SDR SWIA2020021448452](https://openairdocs.org/sdr/SWIA2020021448452), Dec 29, 2019: Cndair CL6002B19. ATTACH BRACKET. CRACKED. RH MLG W/W HYDRAULIC PRESSURE TRANSDUCER ATTACH BRACKET AT LWR SURFACE OF PRESSURE FLOOR SKIN, BROKEN. (C-CHECK) RO 2/10 (N978SW)
- [SDR YADA20191223001](https://openairdocs.org/sdr/YADA20191223001), Dec 18, 2019: Beech 1900C. MASTER CYLINDER. CAVITATES. CAPT AND FO LEFT BRAKE PEDAL UNRESPONSIVE. (N110AX)
- [SDR HYIA20191112004](https://openairdocs.org/sdr/HYIA20191112004), Nov 8, 2019: Cessna 402C. O-RING. LEAKING. PILOT REPORTED RIGHT BRAKE FAILURE. MAINTENANCE INSPECTED AND FOUND AN O-RING IN THE RIGHT MASTER CYLINDER BLEEDING BY.  (N2748Y)

All 445: https://openairdocs.org/jasc/3243/reports.md

## Other codes in chapter 32

- [JASC 3200](https://openairdocs.org/jasc/3200): Landing Gear System (862 reports)
- [JASC 3201](https://openairdocs.org/jasc/3201): Landing Gear/Wheel Fairing (45 reports)
- [JASC 3210](https://openairdocs.org/jasc/3210): Main Landing Gear (1,879 reports)
- [JASC 3211](https://openairdocs.org/jasc/3211): Main Landing Gear Attach Section (1,177 reports)
- [JASC 3212](https://openairdocs.org/jasc/3212): Emergency Flotation Section (759 reports)
- [JASC 3213](https://openairdocs.org/jasc/3213): Main Landing Gear Strut/Axle/Truck (2,210 reports)
- [JASC 3220](https://openairdocs.org/jasc/3220): Nose/Tail Landing Gear (1,842 reports)
- [JASC 3221](https://openairdocs.org/jasc/3221): Nose/Tail Landing Gear Attach Section (256 reports)
- [JASC 3222](https://openairdocs.org/jasc/3222): Nose/Tail Landing Gear Strut/Axle (2,074 reports)
- [JASC 3230](https://openairdocs.org/jasc/3230): Landing Gear Retraction/Extension System (11,170 reports)
- [JASC 3231](https://openairdocs.org/jasc/3231): Landing Gear Door Retract Section (2,248 reports)
- [JASC 3232](https://openairdocs.org/jasc/3232): Landing Gear Door Actuator (740 reports)
- [JASC 3233](https://openairdocs.org/jasc/3233): Landing Gear Actuator (2,685 reports)
- [JASC 3234](https://openairdocs.org/jasc/3234): Landing Gear Selector (2,085 reports)
- [JASC 3240](https://openairdocs.org/jasc/3240): Landing Gear Brake System (6,451 reports)
- [JASC 3241](https://openairdocs.org/jasc/3241): Brake Anti-Skid Section (1,310 reports)
- [JASC 3242](https://openairdocs.org/jasc/3242): Brake (1,696 reports)
- [JASC 3244](https://openairdocs.org/jasc/3244): Tire (2,748 reports)
- [JASC 3245](https://openairdocs.org/jasc/3245): Tire Tube (390 reports)
- [JASC 3246](https://openairdocs.org/jasc/3246): Wheel/Ski/Float (2,489 reports)
- [JASC 3250](https://openairdocs.org/jasc/3250): Landing Gear Steering System (2,362 reports)
- [JASC 3251](https://openairdocs.org/jasc/3251): Steering Unit (338 reports)
- [JASC 3252](https://openairdocs.org/jasc/3252): Shimmy Damper (79 reports)
- [JASC 3260](https://openairdocs.org/jasc/3260): Landing Gear Position and Warning (13,418 reports)
- [JASC 3270](https://openairdocs.org/jasc/3270): Auxiliary Gear (Tail Skid) (84 reports)
- [JASC 3297](https://openairdocs.org/jasc/3297): Landing Gear System Wiring (2,407 reports)

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