# JASC 6120: Propeller Controlling System

- Type: JASC system/component code (FAA)
- ATA chapter: 61 Propeller/Propulsors
- Title in the code table: PROPELLER CONTROLLING SYSTEM
- Service difficulty reports: 1,421
- FAA code table: https://www.faa.gov/sites/faa.gov/files/JASC_Code.pdf#page=56
- Page: https://openairdocs.org/jasc/6120

## What it covers

For general reports of propeller speed controlling other than the governor unit or the synchronizer. Includes the controlling systems of propellers regardless of the propeller type. (Includes propeller regulator, negative torque switch, and the rigging mechanism). Also includes governor control linkage, levers, cable, and associated brackets from the cockpit to the governor; and the feather and unfeathering systems except the pump and accumulator. Typical parts are cable, bellcrank, lever, rod end, pressure switch, solenoid valve, beta switch, etc.

## Service difficulty reports (1,421, newest 50)

- [SDR HYIA20260522001](https://openairdocs.org/sdr/HYIA20260522001), May 14, 2026: Tecnam P2012. GOVERNOR. FAULTED. PILOT REPORTED AN UN-COMMANDED FEATHER ON THE RIGHT ENGINE. MAINTENANCE INSPECTED RH PROP AND FOUND NO DEFECTS NOTED AT  (N989CA)
- [SDR 2026FA0000203](https://openairdocs.org/sdr/2026FA0000203), Mar 20, 2026: Piper PA24260. CONTROL CABLE. BROKEN. AIRCRAFT ABORTED TAKEOFF DUE TO LOW POWER. UPON INSPECTION FOUND PROPELLOR GOVERNOR CABLE BROKEN. MAINTENANCE REPLACED T (N9055P)
- [SDR 2024FA0000723](https://openairdocs.org/sdr/2024FA0000723), Sep 18, 2024: Beech B300. SOLENOID. WORN. THE LH PROPELLER PITCH SOLENOID WAS STICKING AND NEEDED TO BE REPLACED. WAS NOT ALLOWING THE THROTTLE TO ADVANCE PROPERL (N555AL)
- [SDR 7C7A2023040600025](https://openairdocs.org/sdr/7C7A2023040600025), Apr 1, 2023: Dhav DHC8106. PCU. FAILED. THIS IS FILLING IN DETAILS FOR SDR FILED ON 4/1/2023 7C7A2023040100020 ENGINE TORQUE INCREASED 3% UNCOMMAND IN FLIGHT. R (N887EA)
- [SDR QXEA2022122700346](https://openairdocs.org/sdr/QXEA2022122700346), Dec 27, 2022: Bombdr DHC8402. PEC. MALFUNCTIONED. AUTO FEATHER DID NOT ARM WITH POWER LEVERS SET IN THE DETENT. REMOVED FROM SERVICE. CDS FAULT 400 - #2 PROP CHANNEL #1 A (N435QX)
- [SDR QXEA2022121500389](https://openairdocs.org/sdr/QXEA2022121500389), Dec 14, 2022: Bombdr DHC8402. CIRCUIT BREAKER. TRIPPED. NR 2 ENGINE ALTERNATE FEATHER PUMP CIRCUIT BREAKER TRIPPED DURING MAINTENANCE UNFEATHERING ATTEMPT. AIRCRAFT DOWN FOR RE (N446QX)
- [SDR QXEA2022120900336](https://openairdocs.org/sdr/QXEA2022120900336), Dec 6, 2022: Bombdr DHC8402. SWITCH. INOPERATIVE. #1 PROP FAILED PROP OVERSPEED GOVENOR TEST. REPLACED OFF SWITCH IAW AMM 31-31-03-960-801 C/W OPERATIONAL TEST OF PROP OV (N443QX)
- [SDR UOIA2022112200004](https://openairdocs.org/sdr/UOIA2022112200004), Nov 22, 2022: Bnorm BN2B26. CONTROL CABLE. LACK OF LUBE. LEFT PROPELLER GETTING STUCK INTERMITTENT. (N904GD)
- [SDR QXEA2022110400315](https://openairdocs.org/sdr/QXEA2022110400315), Nov 1, 2022: Bombdr DHC8402. PEC. NONE. AUTOFEATHER FAILED TEST. INDICATED A/F TEST FAILED ON #1, A/F TEST ABORT ON #2. CDS POSTED FAULT CODE 494 CHANNEL A &B O (N430QX)
- [SDR QXEA2022082200276](https://openairdocs.org/sdr/QXEA2022082200276), Aug 17, 2022: Bombdr DHC8402. NONE. NONE. #1 PROP WILL NOT UNFEATHER FOR MAINTENANCE USING THE ALT FEATHER PUMP. REPLACED THE #1 ENGINE PCU IAW AMM 61-20-11-000-8 (N426QX)
- [SDR 2022FA0000355](https://openairdocs.org/sdr/2022FA0000355), Jul 18, 2022: Beech 300BEECH. GOVERNOR. INOPERATIVE. DURING ENGINE PRE-TAKEOFF PERFORMANCE RUNS, THE #2 PROP WOULD NOT COME OUT OF FEATHER. MAINTENANCE TEAM INSPECTED THE EN (N80)
- [SDR QXEA2022062700233](https://openairdocs.org/sdr/QXEA2022062700233), Jun 25, 2022: Bombdr DHC8402. PROPELLER. SLOW. #1 PROP VERY SLOW TO UNFEATHER TOOK AT LEAST 40-50 SEC TO COME OUT OF FEATHER. REMOVED FROM SERVICE. PERFORMED FUNCTIONA (N403QX)
- [SDR QXEA2022062300229](https://openairdocs.org/sdr/QXEA2022062300229), Jun 23, 2022: Bombdr DHC8402. PROPELLER. SLUGGISH. #1 PROPELLER IS SLOW TO UNFEATHER. REMOVED FROM SERVICE. C/W FUNCTIONAL TEST OF THE PROP TIME TO UNFEATHER PER Q400 AMM  (N403QX)
- [SDR QXEA2022060900215](https://openairdocs.org/sdr/QXEA2022060900215), Jun 6, 2022: Bombdr DHC8402. POWERPLANT. ACTIVATION ERROR. POWERPLANT MESSAGE ON FD DURING APPROACH. REMOVED FROM SERVICE. CDS SHOWS FAULT CODE 428 A/B #1 PROP. Q HI OUTPUT FAULT. (N427QX)
- [SDR T4OR2022082400001](https://openairdocs.org/sdr/T4OR2022082400001), Apr 4, 2022: Beech B300. PITCH LINK. GALLED. NEWLY OVERHAULED PROPS, HARTZELL PN HC-B4MP-3C, ON KING AIR B300. INFLIGHT, WHEN POWER WAS REDUCED FOR LANDING, THE PROP (N350KD)
- [SDR QXEA2022020900050](https://openairdocs.org/sdr/QXEA2022020900050), Feb 7, 2022: Bombdr DHC8402. PEC. NONE. DURING AUTO FEATHER TEST, THE A/F TEST ABORT AND A/F TEST FAILED MESSAGES APPEARED ON THE ED.REMOVED FROM SERVICE. EMU S (N427QX)
- [SDR QXEA2022020100045](https://openairdocs.org/sdr/QXEA2022020100045), Jan 31, 2022: Bombdr DHC8402. PCU. NONE. ON TAKEOFF ROLL AUTOFEATHER FAILED TO ARM. ABORT INITIATED AT APPROXIMATELY 95 KIAS. ABORTED TAKE OFF. REMOVED FROM SERV (N427QX)
- [SDR QXEA2022013100041](https://openairdocs.org/sdr/QXEA2022013100041), Jan 30, 2022: Bombdr DHC8402. NONE. NONE. ABORTED TAKEOFF AT 70-80 KTS A/F FAILED TO ARM CYCLING BETWEEN AF SELECT AND AF ARM. REMOVED FROM SERVICE. INTERROGATED  (N427QX)
- [SDR QXEA2021012700038](https://openairdocs.org/sdr/QXEA2021012700038), Jan 27, 2022: Bombdr DHC8402. PEC. NONE. DESCENDING THROUGH ABOUT 10,000' BOTH PILOTS FELT A ENGINE SURGE. NOTICED THE LEFT ENGINE PROP RPM FLUCTUATING. STABILIZ (N432QX)
- [SDR QXEA2022012400030](https://openairdocs.org/sdr/QXEA2022012400030), Jan 23, 2022: Bombdr DHC8402. NONE. NONE. DURING DAILY SYSTEM CHECKS THE AUTOFEATHER TEST FAILED 3 TIMES IN A ROW. REMOVED FROM SERVICE. INTERROGATED CDS, NO FAUL (N427QX)
- [SDR QXEA2022011100020](https://openairdocs.org/sdr/QXEA2022011100020), Jan 11, 2022: Bombdr DHC8402. NONE. NONE. AUTOFEATHER SYSTEM TEST FAILED DURING DAILY SYSTEMS CHECK. REMOVED FROM SERVICE. INTERROGATED CDS AND FOUND F/C 70A, 398 (N427QX)
- [SDR LR7A2021103102988](https://openairdocs.org/sdr/LR7A2021103102988), Oct 31, 2021: Lkheed 382G. HOUSING. FLUCTUATES. DURING SCHEDULED FLIGHT #4 ENGINE RPM OUT OF LIMITS AT 96.5%. DECLARED AN EMERGENCY. / REPLACED #4 VALVE HOUSING IAW WOR
- [SDR QXEA2021092900455](https://openairdocs.org/sdr/QXEA2021092900455), Sep 28, 2021: Bombdr DHC8402. SEAL. NONE. #2 ENGINE SLOW TO COME OUT OF FEATHER. REMOVED FROM SERVICE. HAD CREW ENGINES #1 & #2. PERFORMED FUNCTIONAL TEST OF PROP (N438QX)
- [SDR QXEA2021092700449](https://openairdocs.org/sdr/QXEA2021092700449), Sep 25, 2021: Bombdr DHC8402. GOVERNOR. MALFUNCTIONED. AFTER START UP, WHEN CONDITION LEVERS WERE ADVANCED FROM START & FEATHER, #2 ENGINE TOOK APPROX. 1 MIN TO COME OUT OF FE (N438QX)
- [SDR LR7A2021090902959](https://openairdocs.org/sdr/LR7A2021090902959), Sep 9, 2021: Lkheed 382G. HOUSING. FLUCTUATES. DURING SCHEDULED FLIGHT #4 RPM FLUX OUT OF LIMITS, ENGINE SHUTDOWN, EMERGENCY DECLARED / REMOVED AND REPLACED #4 VALVE H (N405LC)
- [SDR LR7A2021082002957](https://openairdocs.org/sdr/LR7A2021082002957), Aug 19, 2021: Lkheed 382G44K30. HOUSING. OUT OF LIMITS. DURING SCHEDULED FLIGHT ON TAKE OFF ROLL #1 RPM OUT OF LIMITS & FLUX / REMOVED AND REPLACED #1 VALVE HOUSING IAW HN61135 (N402LC)
- [SDR 9JLA2021080425175](https://openairdocs.org/sdr/9JLA2021080425175), Jul 16, 2021: Piagio P180. SENSOR. DEFECTIVE. THE FLIGHT CREW REPORTED THAT PROPELLER SYNC FAULTED, THE CREW ADVISED, WHEN ENGAGED THE LEFT PROP WOULD SPEED-UP 25 TO  (N989BJ)
- [SDR QXEA2021062400322](https://openairdocs.org/sdr/QXEA2021062400322), Jun 24, 2021: Bombdr DHC8402. PEC. MALFUNCTIONED. ON ENGINE START,PROPS BROUGHT OUT OF START/ FEATHER, #2 PROP TOOK OVER 50 SECONDS TO INCREASE TO THE GREEN ARC. REMOVED  (N438QX)
- [SDR QXEA2021051600240](https://openairdocs.org/sdr/QXEA2021051600240), May 16, 2021: Bombdr DHC8402. PEC. MALFUNCTIONED. CLIMBING THROUGH APPROX 11,000 FT THE "POWERPLANT" MESSAGE ILLUMINATED AND REMAINED ILLUMINATED FOR THE REMAINED OF THE  (N412QX)
- [SDR QXEA2021032800149](https://openairdocs.org/sdr/QXEA2021032800149), Mar 24, 2021: Bombdr DHC8402. PEC. MALFUNCTIONED. WHILE TESTING A/F DURING THE DAILY SYSTEMS CHECKS, #1 ENGINE INDICATES "ABORT" AND #2 ENGINE "FAILED" TEST CONDUCTED TWI (N439QX)
- [SDR QXEA2021032200128](https://openairdocs.org/sdr/QXEA2021032200128), Mar 22, 2021: Bombdr DHC8402. AUTOFEATHER SYS. NO TEST. A/F TEST FAILS TEST, #1 ENGINE ABORT, #2 ENGINE FAILED. REMOVED FROM SERVICE. INTERROGATED CDS . FOUND FAULT 72 CH B ON  (N439QX)
- [SDR QXEA2021031200108](https://openairdocs.org/sdr/QXEA2021031200108), Mar 10, 2021: Bombdr DHC8402. POWER LEVER. MALFUNCTIONED. #2 PEC CAUTION DURING LANDING ROLL THROUGH 50 KTS. POWERPLANT MESSAGE ON ED. RETRIEVED FAULT CODES IAW Q400 AMM 77-31-00 (N446QX)
- [SDR QXEA202103090105](https://openairdocs.org/sdr/QXEA202103090105), Mar 9, 2021: Bombdr DHC8402. POWER LEVER. MALFUNCTIONED. #2 PEC CAUTION LIGHT ILLUMINATED. REQUIRES TO REPLACE THE PLA QUADRANT, AND K-3 OR K-2 RELAY WITHIN 50 FLT AFTER DISCOVE (N446QX)
- [SDR QXEA2021030900105](https://openairdocs.org/sdr/QXEA2021030900105), Mar 9, 2021: Bombdr DHC8402. POWER LEVER. MALFUNCTIONED. #2 PEC CAUTION AFTER TOUCHDOWN WHILE DECELERATING THROUGH 60KTS WITH POWERPLANT MESSAGE DISPLAYED ON ED WHILE PULLING IN (N446QX)
- [SDR LR7A2021012202773](https://openairdocs.org/sdr/LR7A2021012202773), Jan 22, 2021: Lkheed 382G. HOUSING. FAILED. DURING SCHEDULED FLIGHT, NR 1 ENGINE SHUTDOWN FOR OVERSPEED GREATER THAN 102.0%. ENGINE SHUTDOWN AT 1350Z. REMOVED AND R (N410LC)
- [SDR LR7A2020121302647](https://openairdocs.org/sdr/LR7A2020121302647), Dec 13, 2020: Lkheed 382G44K30. HOUSING. OUT OF LIMITS. DURING SCHEDULED FLIGHT, NR 2 ENGINE LOW PROP FLUX OUT OF LIMITS. ENGINE SHUT DOWN, FUEL DUMPED. REPLACED NR 2 PROP PUMP (N403LC)
- [SDR HYIA20201117001](https://openairdocs.org/sdr/HYIA20201117001), Nov 16, 2020: Cessna 402C. GOVERNOR. MALFUNCTIONED. THE PILOT REPORTED THE LEFT PROPELLER STUCK AT 2500 RPMS AT CRUISE FLIGHT, AND WAS UNABLE TO ADJUST. MAINTENANCE INSPECT (N7037E)
- [SDR HYIA20200904002](https://openairdocs.org/sdr/HYIA20200904002), Sep 2, 2020: Cessna 402C. CONTROL CABLE. BROKEN. THE PILOT REPORTED THAT THE RIGHT PROPELLER RAN AWAY IN FLIGHT, BUT DID NOT OVERSPEED. MAINTENANCE INSPECTED AND FOUND T (N401TJ)
- [SDR QXEA2020062400260](https://openairdocs.org/sdr/QXEA2020062400260), Aug 22, 2020: Bombdr DHC8402. TRANSDUCER. MALFUNCTIONED. POWERPLANT MESSAGE ILLUMINATED ON ED DURING CLIMB @ 10'000'. RETURNED TO FIELD. LANDING UNEVENTFUL, REMOVED FROM SERVICE (N405QX)
- [SDR QXEA2020081000236](https://openairdocs.org/sdr/QXEA2020081000236), Aug 10, 2020: Bombdr DHC8402. PEC. MALFUNCTIONED. UPON C/W FUNCTIONAL TEST OF THE PEC CALIBRATION PROCEDURE PER AMM 61-20-36-720-802, NR2 PROP FAILED TO UNFEATHER PER PAR (N400QX)
- [SDR MTNA202008210001](https://openairdocs.org/sdr/MTNA202008210001), Jul 14, 2020: Aerosp ATR42300. O-RING. LEAKING. DURING CRUISE RT TORQUE UNCOMMENCED TORQUE INDICATED 120%, ACCOMPANIED AIRPLANE ASSEMETRY. MAINTENANCE FOUND PROPELLER C (N918FX)
- [SDR MTNA202008172101](https://openairdocs.org/sdr/MTNA202008172101), Jul 14, 2020: Aerosp ATR42300. O-RING. LEAKING. DURING CRUIS, RIGHT UNCOMMANDED TORQUE INDICATED 120%, ACCOMPANIED BY AIRPLANE ASYMMETRY. REPLACED #2 PROPELLER CONTROL  (N918FX)
- [SDR QXEA2020071400207](https://openairdocs.org/sdr/QXEA2020071400207), Jul 14, 2020: Bombdr DHC8402. UNKNOWN. MALFUNCTIONED. AFTER ENGINE STAR FLOW A/F SELECT DID NOT ILLUMINATED ON ED. REMOVED FROM SERVICE. CYCLED A/C POWER AND FOUND FAULT 100  (N401QX)
- [SDR QXEA2020070700201](https://openairdocs.org/sdr/QXEA2020070700201), Jul 7, 2020: Bombdr DHC8402. PCU. INOPERATIVE. NR 2 PROP DID NOT COMPLETELY FEATHER DURING SHUTDOWN. REMOVED FROM SERVICE. PERFORMED FEATHER CHECK OF NR 2 ENGINE PER A (N444QX)
- [SDR QXEA2020070100199](https://openairdocs.org/sdr/QXEA2020070100199), Jul 1, 2020: Bombdr DHC8402. PEC. MALFUNCTIONED. NR 2 AUTOFEATHER FAILED TO ARM ON TAKEOFF ROLL. TAKEOFF ABORTED 80 KTS GROUNDSPEED REACHED. NO EXCESSIVE BRAKING. REMOVE (N439QX)
- [SDR 2020FA0000537](https://openairdocs.org/sdr/2020FA0000537), Jun 2, 2020: Cessna 208B. ROD END BEARING. DRY. PILOT REPORTS PROPELLER CONTROLS DIFFICULT TO MOVE INTO BETA. UPON FURTHER INSPECTION FOUND ENGINE CONTROL RODS NEEDED T (N208AR)
- [SDR LR7A2020051502254](https://openairdocs.org/sdr/LR7A2020051502254), May 13, 2020: Lkheed 382G. HOUSING. MALFUNCTIONED. DURING SCHEDULED FLIGHT #1 ENGINE RPM WENT TO 103%. ENGINE SHUTDOWN / REPLACED OUTBOARD VALVE HOUSING. IAW HN61135. LP 9
- [SDR QXEA2020022400116](https://openairdocs.org/sdr/QXEA2020022400116), Feb 22, 2020: Bombdr DHC8402. PEC. MALFUNCTIONED. A/F ARM FAILED ON TAKEOFF ROLL, ABORTED TAKEOFF AT 70 KNOTS. A/F SELECT ONLY. RETURNED TO GATE. REMOVED FROM SERVICE. RE (N427QX)
- [SDR QXEA2020022000111](https://openairdocs.org/sdr/QXEA2020022000111), Feb 19, 2020: Bombdr DHC8402. PEC. MALFUNCTIONED. AUTOFEATHER FAILS TO TEST PROPERLY. #1 TORQUE SHOWS 100% & #2 TORQUE SHOWS 90% WHEN AUTOFEATHER TEST IS ACCOMPLISHED. PO (N427QX)
- [SDR 2020FA0000156](https://openairdocs.org/sdr/2020FA0000156), Feb 13, 2020: SWITCH. FAILED. DURING AN ACCIDENT INVESTIGATION ON A VELOCITY AIRCRAFT (EXPERIMENTAL/AMATEUR BUILT) WITH A IVO PROPELLER (MAGNUM) INSTA (N78BM)

All 1,421: https://openairdocs.org/jasc/6120/reports.md

## Other codes in chapter 61

- [JASC 6100](https://openairdocs.org/jasc/6100): Propeller System (193 reports)
- [JASC 6110](https://openairdocs.org/jasc/6110): Propeller Assembly (1,590 reports)
- [JASC 6111](https://openairdocs.org/jasc/6111): Propeller Blade Section (1,724 reports)
- [JASC 6112](https://openairdocs.org/jasc/6112): Propeller Deice Boot Section (119 reports)
- [JASC 6113](https://openairdocs.org/jasc/6113): Propeller Spinner Section (364 reports)
- [JASC 6114](https://openairdocs.org/jasc/6114): Propeller Hub Section (1,249 reports)
- [JASC 6121](https://openairdocs.org/jasc/6121): Propeller Synchronizer Section (37 reports)
- [JASC 6122](https://openairdocs.org/jasc/6122): Propeller Governor (708 reports)
- [JASC 6123](https://openairdocs.org/jasc/6123): Propeller Feathering/Reversing (919 reports)
- [JASC 6130](https://openairdocs.org/jasc/6130): Propeller Braking (22 reports)
- [JASC 6140](https://openairdocs.org/jasc/6140): Propeller Indication System (292 reports)
- [JASC 6197](https://openairdocs.org/jasc/6197): Propeller/Propulsor System Wiring (99 reports)

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