# JASC 6710: Main Rotor Control

- Type: JASC system/component code (FAA)
- ATA chapter: 67 Rotors Flight Control
- Title in the code table: MAIN ROTOR CONTROL
- Service difficulty reports: 1,151
- FAA code table: https://www.faa.gov/sites/faa.gov/files/JASC_Code.pdf#page=59
- Page: https://openairdocs.org/jasc/6710

## What it covers

The system components and parts other than the servo control system which control and indicates the attitude or the angle of attack of the main rotor blades. Typical parts are collective pitch lever, cyclic pitch stick, coupling and mixing units, and position indicators, etc.

## Service difficulty reports (1,151, newest 50)

- [SDR QMLA2026030820016](https://openairdocs.org/sdr/QMLA2026030820016), Mar 8, 2026: Urocop EC135P2. COLLECTIVE. LOOSE. HEALTHNET 1 WAS DISPATCHED FOR AN IFT FROM RUBY TO WEST PENN. WE WERE TURNING LONG FINAL FOR BRAVO PAD, AND I WAS GETTIN (N492AE)
- [SDR 2025FA0000647](https://openairdocs.org/sdr/2025FA0000647), Sep 12, 2025: Bolkms BK117C2. VARTOMS. FAULTED. VARTOMS SYSTEM KICKED INTO MANUAL MODE AS ENGINES COULDN'T HOLD TORQUE MATCHING AT THE SPECIFIC POWER SETTING. SYSTEM WA (N240SF)
- [SDR 2025FA0000014](https://openairdocs.org/sdr/2025FA0000014), Jan 3, 2025: Bolkms BK117C2. COLL PITCH CNTR. ABNORMAL. COLLECTIVE FRICTION WAS TOO LIGHT ALLOWING COLLECTIVE TO FALL WHEN HANDS OFF CONTROLS. FOUND THE COLLECTIVE FRICTION KNO (N140SF)
- [SDR 2024FA0000193](https://openairdocs.org/sdr/2024FA0000193), Feb 28, 2024: Robsin R44RAVENII. BOOT. DEBONDED. C156-2 BLADE BOOTS FAILED. THE RUBBER IS DELAMINATING. WE HAVE SEEN THIS FROM 3 PAIRS OF THE LATEST REVISION OF BOOTS AN (N446TC)
- [SDR U0GA202311150001](https://openairdocs.org/sdr/U0GA202311150001), Nov 13, 2023: Skrsky S76C. CONTROL ROD. DAMAGED. BRISTOW RECENTLY DISCOVERED A LOOSE JAM NUT ON AFT M/R SERVO INPUT ROD END DURING A SCHEDULED INSPECTION. THE JAM NUT IS (N760BG)
- [SDR U0GA FCD 00487](https://openairdocs.org/sdr/U0GA%20FCD%2000487), Sep 12, 2023: Urocop EC135P2. CONTROL ROD. CRACKED. DURING AIRCRAFT INSPECTION PROMPTED BY SIMILAR DEFECT ON ANOTHER FLEET AIRCRAFT. CRACK FOUND ON LH (LONGITUDNAL) MR SERV (N228BJ)
- [SDR U0GA TL 248039](https://openairdocs.org/sdr/U0GA%20TL%20248039), Sep 12, 2023: Urocop EC135P2. CONTROL ROD. CRACKED. DURING AIRCRAFT INSPECTION PROMPTED BY SIMILAR DEFECT ON ANTHER FLEET AIRCRAFT. CRACK FOUND ON LH (LONGITUDNAL) MR SERVO (N325DB)
- [SDR U0GA TL 247933](https://openairdocs.org/sdr/U0GA%20TL%20247933), Sep 11, 2023: Urocop EC135P2. CONTROL ROD. CRACKED. DURING AIRCRAFT AAIP INSPECTION CRACK FOUND ON LH (LONGITUDNAL) MR SERVO INPUT FLIGHT CONTROL ROD. REF EC135P2+ IPC IPC  (N127JL)
- [SDR U0GA202307072410](https://openairdocs.org/sdr/U0GA202307072410), Jul 6, 2023: Agusta A109E. LOCK NUT. CRACKED. WHILE PERFORMING THE POST FLIGHT CHECK IT WAS FOUND THAT THE SWASHPLATE SUPPORT WAS LOOSE AT ITS MOUNTING POINT. UPON FU (N820FT)
- [SDR QR9R202305220002](https://openairdocs.org/sdr/QR9R202305220002), May 22, 2023: Bolkms BK117C2. ACTUATOR. WARNING MESSAGE. ACTUATER FAIL CAUTION MESSAGE AND CIRCUT BREAKER POPPED 45 MINUTES INTO FLIGHT. BACKUP SAS AND ACTUATOR MESSAGES INDICAT
- [SDR HDNA20220629001](https://openairdocs.org/sdr/HDNA20220629001), Jun 29, 2022: Bolkms BK117C2. CONTROL ROD. CRACKED. MAINTENANCE NOTED DURING THE PERFORMANCE OF A "DAILY AIRWORTHINESS CHECK" MULTIPLE CRACKS AT THE FORWARD END OF THE NON- (N145FH)
- [SDR QR9R20220624001](https://openairdocs.org/sdr/QR9R20220624001), Jun 24, 2022: Bolkms BK117C2. ACTUATOR. ILLUMINATED. P ACTUATOR FAILURE ON TAKEOFF FROM PAD. DURING TEST FLIGHT EVALUATION, ACTUATOR LIGHT ILLUMINATED ON CAD WITH A MOMENTAR
- [SDR XSFA20211016001](https://openairdocs.org/sdr/XSFA20211016001), Oct 16, 2021: Snias AS350B2. SPRING. MISINSTALLED. WHILE CONVERTING AIRCRAFT CONFIGURATION FROM SINGLE PILOT CONTROLS TO DUAL PILOT CONTROLS FOR PILOT TRAINING, MECHANIC F (N963SA)
- [SDR 2A6R202107016112](https://openairdocs.org/sdr/2A6R202107016112), Jul 2, 2021: Urocop EC135P2. SHAFT. CORRODED. DURING 1000 HOUR AIR FRAME INSPECTION, FOUND THE COLLECTIVE SHAFT UNDER THE COCKPIT FLOOR CORRODED BEYOND LIMITS. (N135HN)
- [SDR 2021FA0000063](https://openairdocs.org/sdr/2021FA0000063), Feb 26, 2021: SHAFT. MISMANUFACTURED. FOLLOWING A WRONG REPAIR PROCESS OF THE FREEWHEEL SHAFT, IT HAS BEEN OBSERVED A CASEHARDENING THICKNESS MEASURED AT 0.7  (N37214)
- [SDR QMLA2020052920024](https://openairdocs.org/sdr/QMLA2020052920024), May 28, 2020: Bolkms BK117C2. COLLECTIVE STICK. CORRODED. DURING INSPECTION A 4360.3 ITEM 3.4.4 FOUND CORROSION ON THE COPILOT SIDE COLLECTIVE SHAFT AT THE WELD FOR COLLECTIVE LE (N145HN)
- [SDR X2RA2020061500001](https://openairdocs.org/sdr/X2RA2020061500001), May 5, 2020: Hughes 369D. BEARING. SEIZED. PILOT NOTICED THE COLLECTIVE MOTION WAS RATCHETY. INSPECTION FOUND THAT THE BEARINGS, SELF-ALIGNING, WERE SEIZED UP SOLI (N138TX)
- [SDR CA191210010](https://openairdocs.org/sdr/CA191210010), Jul 31, 2019: Bell 407. LINK. FAILED. (CAN) DURING REGULAR 2500HRS INSPECTION. INSERT FAILED PROOF LOADING PREMATURELY (APPROX 100IN-LBS) (TC# 20191210010)
- [SDR YV3R2019071900148](https://openairdocs.org/sdr/YV3R2019071900148), Jul 15, 2019: Robsin R44. SERVO. LEAKING. CUSTOMER REPORTED HYDRAULIC SERVO P/N: D212-1 IS LEAKING.
- [SDR YV3R2019071900147](https://openairdocs.org/sdr/YV3R2019071900147), Jul 15, 2019: Robsin R44. SERVO. LEAKING. CUSTOMER REPORTED HYDRAULIC SERVO P/N: D212-1 IS LEAKING FROM CONTROL VALVE SIDE PLATES.
- [SDR YV3R2019071900146](https://openairdocs.org/sdr/YV3R2019071900146), Jul 15, 2019: Robsin R44. SERVO. LEAKING. CUSTOMER REPORTED HYDRAULIC SERVO P/N: D212-1 IS LEAKING FROM CONTROL VALVE SIDE PLATES.
- [SDR YV3R2019071900145](https://openairdocs.org/sdr/YV3R2019071900145), Jul 15, 2019: Robsin R44. SERVO. LEAKING. CUSTOMER REPORTED HYDRAULIC SERVO P/N: D212-1 IS LEAKING FROM CONTROL VALVE SIDE PLATES.
- [SDR YV3R2019071800144](https://openairdocs.org/sdr/YV3R2019071800144), Jul 15, 2019: Robsin R44RAVENII. SERVO. LEAKING. CUSTOMER REPORTED HYDRAULIC SERVO ASSEMBLY P/N: D212-1 LEAKED UPON TESTING AFTER INSTALLATION.
- [SDR YV3R2019012200143](https://openairdocs.org/sdr/YV3R2019012200143), Jul 15, 2019: Robsin R44RAVENII. SERVO. LEAKING. CUSTOMER REPORTED HYDRAULIC SERVO ASSEMBLY P/N: D212-1 LEAKED UPON TESTING AFTER INSTALLATION.
- [SDR YV3R2019071800142](https://openairdocs.org/sdr/YV3R2019071800142), Jul 15, 2019: Robsin R44RAVENII. SERVO. LEAKING. CUSTOMER REPORTED HYDRAULIC SERVO ASSEMBLY P/N: D212-1 LEAKED UPON TESTING AFTER INSTALLATION.
- [SDR 2A6R2019062052804](https://openairdocs.org/sdr/2A6R2019062052804), Jun 20, 2019: Urocop EC135P2. SHAFT. CORRODED. DURING INSPECTION FOUND CORROSION ON THE COLLECTIVE SHAFT AT THE FRICTION BRAKE ATTACHMENT POINT. WILL REMOVE AND REPLAC (N911EF)
- [SDR E3MA2019051000001](https://openairdocs.org/sdr/E3MA2019051000001), May 8, 2019: Urocop EC135T2. ACTUATOR. CORRODED. DURING COMPLIANCE WITH EASB EC135-67A-039 PITTING WAS DISCOVERED ON CONNECTING ROD OF THE LATERAL HYDRAULIC ACTUATOR. (N884ME)
- [SDR E3MA2019051000002](https://openairdocs.org/sdr/E3MA2019051000002), May 6, 2019: Urocop EC135P2. ACTUATOR. CORRODED. DURING COMPLIANCE WITH EASB EC135-67A-039 PITTING WAS DISCOVERED ON CONNECTING ROD OF THE LATERAL HYDRAULIC ACTUATOR. (N703ME)
- [SDR CA190430031](https://openairdocs.org/sdr/CA190430031), Apr 24, 2019: Snias AS350D. FRICTION CUP. WORN. (CAN) HAD COMPLAINT OF FRICTION STICKING, THEN NO FRICTION, FOUND THE FRICTION BALL TO HAVE WEAR ON IT. ALSO HAD THE FRI
- [SDR CA191010017](https://openairdocs.org/sdr/CA191010017), Apr 7, 2019: Skrsky S76C. TRANSDUCER. FAULTED. (CAN) NUMBER 1 DECU FAULT APPEARED. DECU FAULT CLEARED BY RESETTING BATTERY. ON NEXT FLIGHT DECU FAULT REAPPEARED ALONG 
- [SDR YV3R2019012200024](https://openairdocs.org/sdr/YV3R2019012200024), Feb 15, 2019: Robsin R44. SERVO. LEAKING. CUSTOMER REPORTED SERVO P/N: D212-1 LEAKING.
- [SDR 2A6R201810035001](https://openairdocs.org/sdr/2A6R201810035001), Oct 3, 2018: Urocop EC135T2. SHAFT. CORRODED. WHILE INSPECTION OF AN AVIONICS INSTALLATION FOUND CORROSION ON THE COLLECTIVE SHAFT AT THE FRICTION BRAKE ATTACH POINT (N135TG)
- [SDR HEER201804190961](https://openairdocs.org/sdr/HEER201804190961), Apr 16, 2018: Bell 407. ACTUATOR. BINDING. AFTER TAKEOFF, ABOUT TO LEVEL OFF AT 1000 FEET, EXPERIENCED A CYCLIC CONTROL ISSUE. CYCLIC BINDING AND HEAVY CREEP REARW (N410PH)
- [SDR EVCA201803280001](https://openairdocs.org/sdr/EVCA201803280001), Mar 28, 2018: Snias AS350B2. FRICTION BLOCK. DIRTY. AFTER DEPARTING FROM BASE PILOT NOTED THAT CYCLIC WOULD NOT MOVE PAST CENTER IN THE LEFT DIRECTION AFTER FLYING FOR 5 MI (N339AE)
- [SDR CHIR201803303212](https://openairdocs.org/sdr/CHIR201803303212), Mar 12, 2018: Boeing 234. BEAM. CRACKED. AFT ROTOR HEAD WAS IN SHOP FOR A SCHEDULED CENTER ROTOR HUB REPLACEMENT. DURING DISASSEMBLY, HORIZONTAL PIN LOCKING BEAM (N245CH)
- [SDR QMLA2018030418028](https://openairdocs.org/sdr/QMLA2018030418028), Mar 4, 2018: Bolkms BK117B2. CYCLIC CONTROL. MALFUNCTIONED. PILOT CLAIMED THAT IN LEVEL FLIGHT THE CYCLIC FLIGHT CONTROL WOULD NOT MOVE MORE THAN AN INCH IN ANY DIRECTION. TRIED SY (N1174U)
- [SDR HEER20180208017](https://openairdocs.org/sdr/HEER20180208017), Feb 8, 2018: Urocop EC135P2. COLLECTIVE STICK. BINDING. DURING APPROACH, THE COLLECTIVE STARTED BINDING AT 30 TORQUE. PERFORMED A GO AROUND AND RETURNED TO BASE. INCREASE IN CO (N327PH)
- [SDR E3MA2017111600001](https://openairdocs.org/sdr/E3MA2017111600001), Nov 15, 2017: Urocop EC135T2. ACTUATOR. BINDING. DURING A POST ENGINE MAINTENANCE GROUND RUN, THE PILOT COULD NOT MOVE THE CYCLIC IN THE AFT DIRECTION DURING THE HYDRAUL (N944ME)
- [SDR HDNR2017111600001](https://openairdocs.org/sdr/HDNR2017111600001), Nov 13, 2017: Urocop EC135P2. CONTROL ROD. CRACKED. WHILE PERFORMING SCHEDULED MAINTENANCE, CRACKS WERE FOUND IN THE SAS LONGITUDINAL CONTROL ROD. THE CRACKS EXTEND TO THE  (N444YE)
- [SDR FTYR N447BH](https://openairdocs.org/sdr/FTYR%20N447BH), Oct 20, 2017: Bell 407. BEARING. WORN. ROD END BEARING WORN BEYOND LIMITS. (N447BH)
- [SDR JYDR20170810191](https://openairdocs.org/sdr/JYDR20170810191), Aug 9, 2017: Skrsky S64E. PILOT VALVE. SCORED. RIGHT LATERAL SERVO RECEIVED WITH A WHITE-UP OF "RIGHT LATERAL SECOND STAGE PILOT VALVE STUCK". CONFIRMED SECOND STAGE P
- [SDR EVCA201705301](https://openairdocs.org/sdr/EVCA201705301), May 30, 2017: Bell 206L3. TUBE. DAMAGED. WHILE PERFORMING INSPECTION OF THE AIRCRAFT, FOUND ONE CYCLIC TUBE TO HAVE THE FIXEDAND NON ADJUSTABLE CLEVIS ON THE TRA (N269AE)
- [SDR EVCA201705261](https://openairdocs.org/sdr/EVCA201705261), May 25, 2017: Bell 206L4. CONTROL TUBE. ROTATED. FIXED LENGTH COLLECTIVE CONTROL TUBE, FOUND TO HAVE ROTATATED BETWEEN THE CLEVIS AND THE CONTROL TUBE BODY AT THE SERVO  (N782AE)
- [SDR EVCA201705221](https://openairdocs.org/sdr/EVCA201705221), May 22, 2017: Bell 206L4. CONTROL TUBE. ABNORMAL. WHILE PERFORMING INSPECTION OF THE AIRCRAFT FOUND THE COLLECTIVE CONTROL TUBE FOUND TO HAVE ROTATIONAL MOVEMENT BETWEEN  (N559AE)
- [SDR EVCA201705201](https://openairdocs.org/sdr/EVCA201705201), May 20, 2017: Bell 206L1. CONTROL TUBE. ABNORMAL. WHILE PERFORMING PREFLIGHT OF THE AIRCRAFT FOUND ONE CYCLIC TUBE TO HAVE THE FIXED AND NONADJUSTABLE CLEVIS ON THE SERVO (N229AE)
- [SDR EVCA201705173](https://openairdocs.org/sdr/EVCA201705173), May 17, 2017: Bell 206L4. CONTROL TUBE. ABNORMAL. WHILE PERFORMING A PREFLIGHT INSPECTION OF THE AIRCRAFT FOUND COLLECTIVE CONTROL TUBE TO HAVE ONE OF ITS FIXED AND NONAD (N469AE)
- [SDR EVCA201705172](https://openairdocs.org/sdr/EVCA201705172), May 17, 2017: Bell 206L4. TUBE. DAMAGED. WHILE PERFORMING PREFLIGHT OF THE AIRCRAFT FOUND BOTH CYCLIC TUBES PN: 206-001-193-001 SN: US1214 AND US1215 TO HAVE THE (N479AE)
- [SDR EVCA201705171](https://openairdocs.org/sdr/EVCA201705171), May 17, 2017: Bell 206L4. TUBE. DAMAGED. WHILE PERFORMING PREFLIGHT OF THE AIRCRAFT FOUND BOTH CYCLIC TUBES TO HAVE THEIR FIXED AND NON ADJUSTABLE CLEVISES TO BE (N479AE)
- [SDR 2016FA0000485](https://openairdocs.org/sdr/2016FA0000485), Oct 11, 2016: Snias AS350B3. MIXING UNIT. MISINSTALLED. MAIN ROTOR FLIGHT CONTROL MIXING UNIT HAS BLIND RIVET FASTENERS IN USE WHERE THE ANTICIPATOR CONTROL ARM ATTACHES THE MI (N853BP)
- [SDR 7AJA20160608003](https://openairdocs.org/sdr/7AJA20160608003), Jun 2, 2016: Snias AS350B3. CONTROL SERVO. UNRELIABLE. UPON APPROACH, THE AMBER SERVO CAUTION ANNUNCIATOR ILLUMINATED. NO LOSS OF FLIGHT CONTROL WAS OBSERVED. IT WAS FOUND THA (N866M)

All 1,151: https://openairdocs.org/jasc/6710/reports.md

## Other codes in chapter 67

- [JASC 6700](https://openairdocs.org/jasc/6700): Rotorcraft Flight Control (317 reports)
- [JASC 6711](https://openairdocs.org/jasc/6711): Tilt Rotor Flight Control (11 reports)
- [JASC 6720](https://openairdocs.org/jasc/6720): Tail Rotor Control System (852 reports)
- [JASC 6730](https://openairdocs.org/jasc/6730): Rotorcraft Servo System (647 reports)
- [JASC 6797](https://openairdocs.org/jasc/6797): Rotors Flight Control System Wiring (9 reports)

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