# JASC 6123: Propeller Feathering/Reversing

- Type: JASC system/component code (FAA)
- ATA chapter: 61 Propeller/Propulsors
- Title in the code table: PROPELLER FEATHERING/REVERSING
- Service difficulty reports: 919
- FAA code table: https://www.faa.gov/sites/faa.gov/files/JASC_Code.pdf#page=56
- Page: https://openairdocs.org/jasc/6123

## What it covers

The component and parts which store and deliver an energy charge for propeller feathering and unfeathering. Includes the pump and associated motor, switch, circuitry and plumbing which provides the force for feathering the propeller blades for stopping the engine's rotation. Does not include propeller feathering system components which are coded in JASC code 6120, such as lever rod end, adjustment screw, solenoid, valves, etc. Typical parts are pump, motor, switch, accumulator, air valve, seal, etc.

## Service difficulty reports (919, newest 50)

- [SDR KY72026F00003](https://openairdocs.org/sdr/KY72026F00003), Nov 15, 2025: Emb EMB120ER. RELAY. FAULTED. AUTO FEATHER AURAL WARNING ALERT ON TAKEOFF WITH AUTO FEATHER ON. REMOVED & REPLACED RELAY K0161 IAW EMB120 WM 20-20-00  (N366DC)
- [SDR O9IA20241015530LM](https://openairdocs.org/sdr/O9IA20241015530LM), Oct 14, 2024: Beech B200. PRESSURE SWITCH. FAULTED. FROM PILOTS REPORT THRU PRISM SMS: IN CRUISE AT 28,000 FT LEFT HAND ENGINE SEEMED TO WANT TO GO INTO FEATHER. HAPPENED T (N530LM)
- [SDR QMLA2024100320128](https://openairdocs.org/sdr/QMLA2024100320128), Oct 2, 2024: Beech B200GT. FEATHERING SYS. FAULTED. DURING LANDING, THE RIGHT PROP ATTEMPTED TO FEATHER WITH THE AUTO FEATHER SYSTEM ON (AS THROTTLES WERE PULLED BACK FOR L (N912SM)
- [SDR 2023FA0000586](https://openairdocs.org/sdr/2023FA0000586), Oct 5, 2023: Airtrc AT502B. BEARING. CRACKED. PROP ORIGINALLY REMOVED FOR ISSUES WITH PROP NOT FULLY CYCLING THROUGH ITS FULL RANGE OF MOTION. HAD ONE BLADE THAT WAS  (N5197X)
- [SDR QXEA2021081700408](https://openairdocs.org/sdr/QXEA2021081700408), Aug 16, 2021: Bombdr DHC8402. FEATHERING SYS. FAULTED. LAST 2 FLIGHTS #2 PROPELLER HAS FAILED TO FEATHER COMPLETELY ON SHUTDOWN. REMOVED FROM SERVICE. MET A/C, INTERROGATED CD (N445QX)
- [SDR QXEA2021072000367](https://openairdocs.org/sdr/QXEA2021072000367), Jul 18, 2021: Bombdr DHC8402. PROPELLER. MALFUNCTIONED. #2 PROP DID NOT FULLY FEATHER DURING SHUTDOWN, NOTICED DURING WALK AROUND. NOTHING ABNORMAL FELT DURING SHUTDOWN. REMOVE (N445QX)
- [SDR QXEA2021052500269](https://openairdocs.org/sdr/QXEA2021052500269), May 24, 2021: Bombdr DHC8402. PEC. MALFUNCTIONED. DURING SYSTEMS CHECKS, THE #2 AUTOFEATHER TESTS FAILED. REMOVED FROM SERVICE. INTERROGATED CDS FOUND FAULT CODE 402B #2  (N427QX)
- [SDR QXEA2021052400265](https://openairdocs.org/sdr/QXEA2021052400265), May 22, 2021: Bombdr DHC8402. AUTOFEATHER SYS. NO TEST. #2 AUTOFEATHER FAILED TEST FOR DAILY SYSTEM CHECK. REMOVED FROM SERVICE. PERFORMED OPS TEST OF THE PROP AUTOFEATHER SYST (N427QX)
- [SDR QXEA2021051200234](https://openairdocs.org/sdr/QXEA2021051200234), May 12, 2021: Bombdr DHC8402. AUTOFEATHER SYS. NO TEST. A/F TEST FOR FO DAILY CHECKS #2 FAILED #1 ABORT. REMOVED FROM SERVICE. CYCLED POWER ON A/C. C/W OPS TEST OF PROP AUTOFEA (N439QX)
- [SDR QXEA2021042800199](https://openairdocs.org/sdr/QXEA2021042800199), Apr 27, 2021: Bombdr DHC8402. SWITCH. INOPERATIVE. A/F DID NOT ARM AFTER ADDING POWER FOR TAKEOFF. TAKEOFF ABORTED AROUND 60 KNOTS. REMOVED FROM SERVICE. NO FAULTS PRESENT (N412QX)
- [SDR 2021FA0000099](https://openairdocs.org/sdr/2021FA0000099), Apr 9, 2021: Diamon DA42NG. VALVE. FAILED. PROPELLER UNFEATHER VALVE FAILURE. ENGINE SHUT DOWN DURING NORMAL TRAINING. ENGINE WOULD NOT RESTART BECAUSE PROPELLER W (N42LA)
- [SDR QXEA2021031900121](https://openairdocs.org/sdr/QXEA2021031900121), Mar 18, 2021: Bombdr DHC8402. WARNING MESSAGE. FALSE ACTIVATION. AUTO FEATHER TEST "ABORT FAILED" AMBER MESSAGE ON ED. REMOVED FROM SERVICE. FOUND FAULT CODE 494 ON #2 ENG. PERFORMED FI (N439QX)
- [SDR QXEA2021021800066](https://openairdocs.org/sdr/QXEA2021021800066), Feb 18, 2021: Bombdr DHC8402. AUTOFEATHER SYS. NO TEST. DURING DAILY SYSTEM CHECK THE NR 1 A/F TEST FAILED. REMOVED FROM SERVICE. CHECKED FOR FAULT CODES, FOUND CODE 494. C/W Q (N427QX)
- [SDR QXEA2020120700344](https://openairdocs.org/sdr/QXEA2020120700344), Dec 6, 2020: Bombdr DHC8402. GOVERNOR. MALFUNCTIONED. NR 1 PROPELLER TOOK =35 SEC TO UNFEATHER ON START UP. REMOVED FROM SERVICE. REPLACED OVERSPEED GOVERNOR ON NR 1 ENGINE,  (N443QX)
- [SDR QXEA2020120300333](https://openairdocs.org/sdr/QXEA2020120300333), Dec 2, 2020: Bombdr DHC8402. PROPELLER. MALFUNCTIONED. DURING MTX TAXI, NR 1 PROP FAILS TO UNFEATHER, ATTEMPTED TO UNFEATHER 5 TIMES NO HELP. C/W FIM 61-20-00-810-803 PARA 1-5 (N443QX)
- [SDR OZCA202011060001](https://openairdocs.org/sdr/OZCA202011060001), Nov 2, 2020: Saab SF340A. SHAFT. SHEARED. 2020 NOV 2ND, N631BC (AS CSQ 726) FLYING FROM GRAND CAYMAN (MWCR) TO MIAMI (KMIA) EXPERIENCED AN UNSCHEDULED PROP FEATHE (N631BC)
- [SDR QXEA2020062600196](https://openairdocs.org/sdr/QXEA2020062600196), Jun 25, 2020: Bombdr DHC8402. AUTOFEATHER SYS. FAULTED. DURING DAILY SYSTEMS NR 2 ENG FAILED AUTO FEATHER CHECK. REMOVED FROM SERVICE. FOUND FAULT CODES 494AB, 228AB, AND 206AB (N439QX)
- [SDR QXEA2020061100180](https://openairdocs.org/sdr/QXEA2020061100180), Jun 10, 2020: Bombdr DHC8402. AUTOFEATHER SYS. MALFUNCTIONED. #2 ENGINE AUTO FEATHER ABORT DURING TEST. REMOVED FROM SERVICE. C/W #2 AUTOFEATHER ABORT FIM TASK 61-20-00-810-805. NO C (N401QX)
- [SDR QXEA2020051100163](https://openairdocs.org/sdr/QXEA2020051100163), May 10, 2020: Bombdr DHC8402. UNKNOWN. MALFUNCTIONED. DURING DAILY SYSTEM CHECK AUTO FEATHER TEST #1 FAIL. REMOVED FROM SERVICE. AUTO FEATHER SYSTEM TEST FAILED. INTERROGATED (N400QX)
- [SDR OZCA2020033100000](https://openairdocs.org/sdr/OZCA2020033100000), Mar 24, 2020: Saab SF340A. PRESSURE SWITCH. FAULTY. FLIGHT CREW WRITE UP - AUTOCOARSEN FAILURE IN FLIGHT. LEFT ENG FEATHERED. "AUTOCOARSEN" CWP ILLUMINATED. LATER AFTER SPE (N681BC)
- [SDR DATA2020031601](https://openairdocs.org/sdr/DATA2020031601), Mar 13, 2020: Stbros SD360200. SWITCH. OUT OF ADJUST. IN CLIMB AT 3500 FEET WHEN PILOTS REDUCED THROTTLE THE RIGHT PROPELLER WENT INTO FEATHER. QRH PROCEDURES FOLLOWED, EMERG (N151CA)
- [SDR QXEA2020021800107](https://openairdocs.org/sdr/QXEA2020021800107), Feb 18, 2020: Bombdr DHC8402. ELECTRONIC UNIT. MALFUNCTIONED. CREW REPORTS ABORTED TAKEOFF AT 60 KNOT DUE TO AUTOFEATHER FAILING TO ARM. ABORTED TAKE OFF. REMOVED FROM SERVICE. R&R # (N427QX)
- [SDR QXEA2020021800106](https://openairdocs.org/sdr/QXEA2020021800106), Feb 18, 2020: Bombdr DHC8402. AUTOFEATHER SYS. MALFUNCTIONED. AUTOFEATHER DIDN'T ARM ON TAKEOFF IN SEATTLE. NOTICED AT V1, CONTINUED TAKEOFF. REMOVED FROM SERVICE. INTERROGATED CDF F (N427QX)
- [SDR QXEA2020021700104](https://openairdocs.org/sdr/QXEA2020021700104), Feb 16, 2020: Bombdr DHC8402. AUTOFEATHER SYS. FAILED. WHILE CONDUCTING DAILY SYSTEM CHECKS, AUTO FEATHER FAILED. POWER LEVERS WERE IN DISC. REMOVED FROM SERVICE. NO CORRELATE (N427QX)
- [SDR QXEA2020021200094](https://openairdocs.org/sdr/QXEA2020021200094), Feb 12, 2020: Bombdr DHC8402. AUTOFEATHER SYS. NO TEST. DURING DAILY SYSTEM CHECK THE AUTO FEATHER TEST FAILED TWICE. REMOVED FROM SERVICE. PERFORMED AF + UPTRIM OPS TEST IAW Q (N427QX)
- [SDR RU3A202002121009](https://openairdocs.org/sdr/RU3A202002121009), Feb 11, 2020: Beech 300BEECH. AUTOFEATHER SYS. MALFUNCTIONED. DURING INITIAL CLIMB OUT RT AUTOFEATHER ANNUNCIATOR EXTINGUISHED. WOULD NOT REARM AT INCREASED PWR SETTINGS. (N84)
- [SDR QXEA2020021200095](https://openairdocs.org/sdr/QXEA2020021200095), Feb 9, 2020: Bombdr DHC8402. AUTOFEATHER SYS. MALFUNCTIONED. UNABLE TO UNFEATHER THE #2 PROPELLER USING THE UNFEATHER SWITCH METHOD. PERFORMED OPERATIONAL TEST OF THE ALTERNATE FEAT (N410QX)
- [SDR JIKA2020011701](https://openairdocs.org/sdr/JIKA2020011701), Jan 17, 2020: Emb EMB120. HMU. FAILED. DURING INITIAL CLIMB, AT ABOUT 1,000 FEET AGL, LH PROPELLER INADVERTENTLY FEATHERED. WE PERFORMED MEMORY ITEMS, FOLLOWED (N567SW)
- [SDR JIKA2020011501](https://openairdocs.org/sdr/JIKA2020011501), Jan 10, 2020: Frchld SA227CC. CONTROL CABLE. MALFUNCTIONED. AFTER TAKEOFF FROM KELM, APPROXIMATELY 600 AGL, RIGHT ENGINE FLAMEOUT. PILOT NOTICED THE RIGHT FUEL FLOW WAS AT ZERO AND (N544UP)
- [SDR JIKA2019083001](https://openairdocs.org/sdr/JIKA2019083001), Aug 27, 2019: Emb EMB120ER. TORQUE SENSOR. INTERMITTENT. THE FLIGHT CREW REPORTED THAT DURING INITIAL CLIMB OUT AT APPROXIMATELY 500 FEET, THERE WAS A PARTIAL LOSS OF POWER ON T (N567SW)
- [SDR CA190807001](https://openairdocs.org/sdr/CA190807001), Aug 3, 2019: Bombdr DHC8400. BOLT. MISSING. (CAN) PILOT REJECTED T.O DUE TO #1 LOW OIL PRESSURE INDICATION. MAINTENANCE FOUND OIL LEAK FORM THE #1 ENGINE, SPECIFICA
- [SDR CA190731030](https://openairdocs.org/sdr/CA190731030), Jul 29, 2019: Dhav DHC6300. SWITCH. MALFUNCTIONED. (CAN) DURING THE TAKE-OFF SLIDE, THE AUTO FEATHER SWITCH WOULD NOT ARM. THE PILOTS ABORTED THE TAKE-OFF AND RETURNED TO 
- [SDR CA190724012](https://openairdocs.org/sdr/CA190724012), Jul 16, 2019: Dhav DHC6300. SWITCH. MALFUNCTIONED. (CAN) THE AUTO FEATHER ARM LIGHT DID NOT TURN ON DURING THE TAKE-OFF SLIDE. THE AUTO FEATHER SWITCH WAS REPLACED, AND TH
- [SDR RU3A20190709032](https://openairdocs.org/sdr/RU3A20190709032), Jul 8, 2019: Beech 300BEECH. UNKNOWN. MALFUNCTIONED. NO AUTO FEATHER RT ENG DURING T/O ROLL. (N72)
- [SDR QXEA2019051300211](https://openairdocs.org/sdr/QXEA2019051300211), May 11, 2019: Bombdr DHC8402. UNKNOWN. MALFUNCTIONED. ON START UP THE NR 2 ENG TAKES AN ABNORMALLY LONG TIME TO COME OUT OF FEATHER. AFTER NR 1 AC GEN LIGHT GOES OUT IT TAKES (N441QX)
- [SDR CA190410013](https://openairdocs.org/sdr/CA190410013), Apr 9, 2019: Dhav DHC8301. TORQUE SENSOR. FAILED. (CAN) #2 PROP COMMANDED FEATHER AT TAKE OFF POWER ON TAKE OFF ROLL. TAKE OFF REJECTED AT 70KTS. CREW REPORTED THAT THE P
- [SDR CA190816008](https://openairdocs.org/sdr/CA190816008), Apr 2, 2019: Raythn B300RAYTHEON. AUTOFEATHER SYS. MALFUNCTIONED. (CAN) AN ATTACHMENT ANCHOR NUT SECURING THE FWD I/B SIDE OF THE OVER-WING LOCKER MODIFICATION THAT WORE INTO THE WIRING 
- [SDR QXEA2019032900145](https://openairdocs.org/sdr/QXEA2019032900145), Mar 26, 2019: Bombdr DHC8402. UNKNOWN. MALFUNCTIONED. #1 PROPELLER WILL NO UNFEATHER USING THE MAINTENANCE PANEL. AIRCRAFT DOWN FOR REPAIRS. (N452QX)
- [SDR CA190319026](https://openairdocs.org/sdr/CA190319026), Mar 19, 2019: Piper PA44180. PROPELLER. MALFUNCTIONED. (CAN) PILOT REPORTED THAT THE RIGHT PROPELLER WAS FEATHERED WHEN HE WENT TO DO HIS WALK AROUND. AN ENGINE RUN WAS CARRIE
- [SDR QXEA2019031800127](https://openairdocs.org/sdr/QXEA2019031800127), Mar 15, 2019: Bombdr DHC8402. LIGHT. INOPERATIVE. AUTOFEATHER BULB IS OUT. REMOVED FROM SERVICE. RE-LAMPED AUTOFEATHER SELECT SWITCH. OPS TEST GOOD. NO FURTHER DEFECTS. A (N401QX)
- [SDR QXEA2018031800126](https://openairdocs.org/sdr/QXEA2018031800126), Mar 13, 2019: Bombdr DHC8402. SWITCH. MALFUNCTIONED. TESTED NR 1 PROPELLER ALTERNATE FEATHER SWITCH ON PROP CONTROL PANEL USING CDS AND ARCDU IAW AMM 61-20-41-710-801. FOUND (N444QX)
- [SDR CA190314011](https://openairdocs.org/sdr/CA190314011), Mar 7, 2019: Dhav DHC6200. SWITCH. FAILED. (CAN) DURING A TRAINING FLIGHT, THE CO-PILOT LET THE NOSE GET TOO HIGH, IN RESPONSE, THE PILOT PUSHED FORWARD AGGRESSIVE
- [SDR CA190315016](https://openairdocs.org/sdr/CA190315016), Mar 2, 2019: Dhav DHC6200. SWITCH. FAILED. (CAN) PILOT REPORTED THAT THE PROPELLER DID NOT FEATHER WHILE CONDUCTING GROUND FUNCTION CHECK OF THE AUTO FEATHER SYSTE
- [SDR CA190227012](https://openairdocs.org/sdr/CA190227012), Feb 23, 2019: Dhav DHC8301. SIGNAL COND UNIT. FAILED. (CAN) 2961 HRS SINCE REPAIR DURING T/O ROLL AS THE LH ENGINE TORQUE WAS RISING TO APPROX 70% THE TORQUE SURGED TO OVER 1
- [SDR QXEA2019021400070](https://openairdocs.org/sdr/QXEA2019021400070), Feb 12, 2019: Bombdr DHC8402. PROPELLER. SLOW. #2 PROPELLER TAKES CLOSE TO 1 MINUTE TO COME OUT OF FEATHER. REMOVED FROM SERVICE. INTERRIGATED CDS. NO FAULTS FOUND. C/ (N433QX)
- [SDR QXEA2019020100057](https://openairdocs.org/sdr/QXEA2019020100057), Feb 1, 2019: Bombdr DHC8402. PROPELLER. NO TEST. #1 PROP FAILED OPERATIONAL CHECK OF THE PROPELLAR ALTERNATE FEATHER REF T/C 612000202 STEP 1 ITEM 2E. PLACED ON MEL 61-2 (N428QX)
- [SDR QXEA2019011100012](https://openairdocs.org/sdr/QXEA2019011100012), Jan 11, 2019: Bombdr DHC8402. UNKNOWN. MALFUNCTIONED. NR 2 PROP FAILS TO UNFEATHER WITH FEATHER PUMP (PROP MTX UNFEATHER(S) INOP). REMOVED FROM SERVICE. PLACED ON MEL 61-20-1 (N437QX)
- [SDR QXEA2019011100011](https://openairdocs.org/sdr/QXEA2019011100011), Jan 10, 2019: Bombdr DHC8402. PUMP. MALFUNCTIONED. FOUND NR 1 ENG ALT FEATHER PUMP TO BE LEAKING AT THE ASSY. JOINTS. REMOVED AND REPLACED #1 FEATHERING PUMP IAW AMM TASK  (N429QX)
- [SDR FXGA201812240001](https://openairdocs.org/sdr/FXGA201812240001), Dec 21, 2018: Doug C118A. PROPELLER. SHEARED. EXCESSIVE VIBRATION ON #4 ENGINE NO OTHER INDICATION PRECAUTIONARY SHUTDOWN #4 ENGINE/ TWO BLADES WENT TO FEATHER THIRD  (N451CE)
- [SDR QXEA2018111200415](https://openairdocs.org/sdr/QXEA2018111200415), Nov 11, 2018: Bombdr DHC8402. PCU. INOPERATIVE. DURING BETA TUBE INSTALLATION FOUND PROP WOULD FEATHER. WOULD NOT UNFEATHER. DISCONNECTED P30 FROM NR 1 PCU & CHECKED CO (N408QX)

All 919: https://openairdocs.org/jasc/6123/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 6120](https://openairdocs.org/jasc/6120): Propeller Controlling System (1,421 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 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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