R44Astro · Raven · Clipper

Parts most often named Magneto (58) · Bearing (17) · Points (13) · Coil (8)

(CAN) FOLLOWING ENGINE START AND DURING POST-START CHECKS ENGINE RPM WAS FOUND TO BE FLUCTUATING. MAGNETO REPLACED WITH OVERHAULED UNIT. (TC# 20190422015)

BENDIX MAGNETO P/N 10-600646-201 WAS REMOVED FOR REPAIR DUE TO POOR TACHOMETER OPERATION. THE TACHOMETER POINTS WERE REPLACED WITH A NEW SET, TELEDYNE CONTINENTAL MOTORS P/N 10-382584. DURING INSTALLATION, CONTINUITY OF THE POINTS WAS CHECKED AND FOUND TO BE OPEN EVEN WHEN THE POINTS WERE CLOSED. THIS PART, WHILE STILL IN ORIGINAL PACKAGING, COULD HAVE BEEN 20 YEARS OLD. A NEW PART OF MUCH MORE RECENT ORIGIN WAS INSTALLED AND CHECKED OKAY FOR CONTINUITY.

THE OVERHAULED MAGNETO WAS PURCHASED. UPON INSTALLATION OF THE MAGNETO, THE TACHOMETER DID NOT WORK. FURTHER TROUBLESHOOTING REVEALED THAT THE TACHOMETER CONTACT ASSEMBLY HAD NO CONTINUITY ACROSS THE POINTS. THE CONTACT ASSEMBLY WAS REPLACED WITH A NEW CONTACT ASSEMBLY.

Parts most often named Tachometer (86) · Dual Tachometer (41) · None (3) · Warning Unit (3)

CUSTOMER REPORTED DUAL TACHOMETER P/N: DC792-4R IS UNSERVICEABLE. OPERATIONAL CHECK REVEALED ENGINE NEEDLE WAS STICKING.

CUSTOMER REPORTED DUAL TACHOMETER ASSEMBLY P/N: C792-4 PEGGED FULL DEFLECTION WITH POWER APPLIED. **COULD NOT LOCATE A/C**

CUSTOMER SENT IN DUAL TACHOMETER ASSEMBLY P/N: C792-4 FOR WARRANTY CONSIDERATION. DURING FUNCTION TESTING, ROTOR NEEDLE FAILED AFTER UNIT WARMED UP.

Parts most often named Actuator (20) · Sprag Clutch (14) · Clutch (12) · Shaft (6)

BUMPS OR BUBBLES WERE FOUND IN THE UPPER SHEAVE GROOVES. THESE SEEM TO BE CORROSION POCKETS BETWEEN THE METALIZED PLATING AND THE CAST ALUMINUM BASE. IF THIS CONTINUED IN [S/N removed], ACCELERATED DRIVE BELT WEAR WILL OCCUR.

AFTER PIC LANDED [tail no. removed] WITH THE COLLECTIVE FULL DOWN, THE CLUTCH LIGHT ILLUMINATED. AFTER LIGHT HAD BEEN ON FOR 10 SECONDS, PIC PULLED THE CLUTCH CIRCUIT BREAKER IN ACCORDANCE WITH THE R44 POH AND ROLLED DOWN THE THROTTLE. PIC THEN SHUT DOWN THE HELICOPTER IAW THE NORMAL PROCEDURES CHECKLIST. ON PILOT'S POST FLIGHT INSPECTION OF THE AIRCRAFT, THE CLUTCH BELTS WERE FOUND TO BE NOT FULLY DISENGAGED. UPON 145 INSPECTION, CLUTCH ACTUATOR FOUND TO BE BROKEN/[S/N removed]. PART WAS REMOVED FROM [S/N removed] AND DOCUMENTED.

DURING THE 100 HOUR INSPECTION, THE CLUTCH LUBRICATION INSPECTION WAS PERFORMED PER ROBINSON MM 7.210. WHEN THE OIL WAS INSPECTED SEVERAL PIECES OF METAL WERE FOUND. ROBINSON WAS CONTACTED AND THE CLUTCH ASSEMBLY WAS REMOVED FROM THE AIRCRAFT AND AN OVERHAULED UNIT WAS INSTALLED.

Parts most often named Starter Gen (49) · Housing (5) · Gear (5) · Starter (5)

THE STARTER BENDIX DRIVE WOULD STICK OUT AND GET STUCK ON RT WING GEAR AND WOULD NOT RETRACT. THE STARTER WOULD NOT TURN ENGINE OVER.

(CAN) DURING INSP, STARTER WAS SLOW TO TURN AND EVENTUALLY FAILED TO FUNCTION. STARTER WAS REMOVED AND NO FURTHER ISSUES WERE NOTED.

(CAN) DURING A DI CONDUCTED BY MX IT WAS NOTED THAT THE HOUSING WAS FOUND CRACKED. STARTER RING GEAR WAS ALSO REPLACED DUE TO DAMAGED TEETH. STARTER WAS REPLACED AND NO ISSUES ISSUES WERE NOTED.

Parts most often named Starter (54) · Gear (4) · Ring Gear (2) · Shaft (1)

(CAN) DURING ACFT 50 HR INSPECTION, THE STARTER WAS FOUND TO HAVE A CRACK APPROXIMATELY 1.5" IN LENGTH IN THE GEAR CASING. STARTER REPLACED.

(CAN) ON ENGINE START PILOT NOTED A BANG THEN THE STARTER MOTOR SPUN UP FAST. HE GOT OUT TO INVESTIGATE AND FOUND THE BENDIX GEAR LAYING ON THE GROUND. THE GEAR SHAFT SHEARED ON THE FWD END IN SIDE OF THE STARTER HSG. IT APPEARS TO HAVE BEEN CRACKED FOR SOME TIME. A NEW STARTER WAS INSTALLED.

(CAN) DURING ENGINE START, STARTER WOULD NOT ENGAGE THE FLYWHEEL. STARTER WAS REPLACED WITH [S/N removed] UNIT. NEW STARTER FUCTION TESTED, NO DEFECTS FOUND.

Parts most often named Pump (59) · Diaphragm (2) · Motor (1) · Bolt (1)

(CAN) AUXILIARY FUEL PUMP LOW PRESSURE WARNING ILLUMINATED DURING FLIGHT. PUMP REPLACED AFTER LANDING. DEFECT RECTIFIED.

(CAN) THE FUEL PUMP WAS NOTED TO BE LEAKING FUEL BY GROUND CREWS AFTER 2.1 HOURS’ TIME SINCE NEW. THE FUEL PUMP HAD BEEN INSTALLED NEW ON THE ENGINE. AS PART OF A NEW EXCHANGE ENGINE PURCHASED & INSTALLED DURING AN OVERHAUL. THE FUEL PUMP WAS LEAKING FROM THE OVERBOARD DRAIN HOSE, WHICH IS A TATTLE TALE THAT CAN EITHER LEAK ENGINE OIL OR FUEL, DEPENDING ON WHICH PART OF THE FUEL PUMP FAILS.

(CAN) DURING THE GROUND RUN FOLLOWING THE 50/100 HR INSPECTION THE AUXILIARY FUEL PUMP WAS FOUND TO BE CAVITATING. AUXILIARY FUEL PUMP REMOVED AND AUXILIARY FUEL PUMP, PN: D8187-B, TSO 1123 HRS WAS INSTALLED. SECOND AUXILIARY FUEL PUMP WAS FOUND TO BE INOPERATIVE. AUXILIARY FUEL PUMP REPLACED.

Parts most often named Pump (47)

LOW FUEL PRESSURE LIGHT ILLUMINATED IN FLIGHT. NO ENGINE ROUGHNESS. VERIFIED ELECTRICAL FUEL PUMP NOT RUNNING. REPLACED ASSY PN D743-3 ASSY PER MM. THIS IS A COMMON ISSUE WITH THE R44 RAVEN II.

(CAN) AUXILIARY ELECTRIC FUEL PUMP LIGHT CAME ON DURING FLIGHT (LIGHT INDICATES LOW FUEL PUMP OUTPUT PRESSURE). PUMP FOUND TO BE UNSERVICEABLE. PUMP REPLACED WITH NEW UNIT, OPERATIONAL TEST CARRIED OUT, PUMP OPERATION FOUND TO BE CORRECT. (TC# 20190422017)

(CAN) DURING ACFT START SEQUENCE, WHILE PRIMING THE ENGINE THE PUMP MADE A SQUEALING NOISE AND WHEN THE ENGINE WAS STARTED THE AUXILIARY FUEL PUMP WARNING LIGHT CAME ON. ACFT CONTINUED TO RUN ON THE GROUND USING ONLY THE MECHANICAL FUEL PUMP. AFTER THE ENGINE WAS SHUTDOWN, WE TESTED THE PUMP USING THE PRIME SWITCH AND NOTED COMPLETE FAILURE OF THE PUMP. CHOSE ACFT MFG SINCE THE PUMP CAN BE ORDERED FROM THEM.

Parts most often named Actuator (22) · V-Belt (5) · Motor (4) · None (3)

CUSTOMER SHEAVE, LOWER P/N: A493-1 RECEIVED FOR WARRANTY. AFTER EVALUATION, BASE MATERIAL (ALUMINUM) HAD CORROSION, WHICH CAUSED BUBBLING BETWEEN ALUMINUM AND METALIZED COATING MATERIAL.

CUSTOMER REPORTED PILOT MADE A PRECAUTIONARY LANDING AFTER AMBER CLUTCH LIGHT ILLUMINATED. AFTER INSPECTION, IT WAS NOTED ONE OF THE BELTS P/N: A190-3 FAILED.

FLICKERING CLUTCH LIGHT NOTED. ON INSPECTION OF CLUTCH ACTUATOR FOUND ONE OF TWO TENSION SPRING SWITCHES TO NOT CLOSE ON ENGAGEMENT. FOUND SWITCH TO BE GOOD, ACTUATOR SPRING TENSION DID NOT MATCH OPPOSITE SIDE AND WAS NOT ENGAGING SWITCH WHEN ACTUATOR EXTENDED TO SET LIMITS. ACTUATOR REPLACED WITH OVERHAULED UNIT.

Parts most often named Servo (39) · Seal (3) · Pilot Valve (1)

(CAN) HYDRAULIC SERVO FOUND TO BE LEAKING FLUID FROM TOP SEAL. HYDRAULIC SERVO [S/N removed], TSO 1711, ALSO FOUND TO BE LEAKING FROM TOP SEAL. BOTH [S/N removed] REPLACED.

(CAN) HYDRAULIC SERVO FOUND LEAKING DURING 100 HR INSPECTION. 2 OTHER [S/N removed] ALSO FOUND TO BE LEAKING. ALL 3 HYDRAULIC [S/N removed] REPLACED.

(CAN) SERVO LEAKING EXCESSIVELY FROM PILOT VALVE AND LOWER SEAL. DISCOVERED DURING ANNUAL INSPECTION, A POOL OF HYDRAULIC FLUID UNDER THE SERVO AND RUNNING THE FRONT OF THE TRANSMISSION ONTO THE MOUNTS AND TRANSMISSION DECK. HYDRAULIC FLUID WAS ALSO COVERING THE BOTTOM OF THE SERVO. SERVO REMOVED FOR REPAIR.

Parts most often named Intake Valve (17) · Exhaust Valve (7) · Cylinder (3) · Valve (3)

ABOUT 30 MINUTES INTO A TOUR, PILOT HEARD A SOUND AND EXPERIENCED LOSS OF POWER AND HIGH MANIFOLD PRESSURE. INITIATED POWER ON LANDING ON AN ADJACENT OPEN FIELD. VISUAL INSPECTION REVEALED OIL LEAK NEAR CYLINDER # 6. UPON REMOVAL OF VALVE COVER A BROKEN OFF VALVE STEM TIP WAS IDENTIFIED. NEW STYLE ROTATOR CUP INTAKE VALVE PN 17A29467 INSTALLED.

DURING BORE SCOPE INSPECTION OF CYLINDER ASSEMBLIES THE NUMBER 3 CYLINDER EXHAUST VALVE WAS FOUND TO BEY HEAVILY PITTED ON VALVE BELL. THE ENGINE HAS ACCUMULATED 398.4 HOURS SINCE MAJOR OVERHAUL. NEW CYLINDER ASSEMBLIES INCLUDING VALVES WERE INSTALLED AT OVERHAUL AT ENGINE TOTAL TIME 2041.0. THIS IS THE JUST LATEST EVENT IN A GROWING TREND OF INTAKE AND EXHAUST VALVE DEFECTS AND FAILURES IN OUR FLEET OF LYCOMING POWERED AIRCRAFT.

PILOT IDENTIFIED HIGH MANIFOLD PRESSURE REQUIRED AFTER TAKE OFF AND PERFORMED A PRE CAUTIONARY LANDING OFF AIRPORT. INSPECTION REVEALED A WET SPARK PLUG ON CYLINDER # 6. AFTER REMOVAL OF THE VALVE COVER, A BROKEN INTAKE VALVE TIP WAS DISCOVERED. NEW STYLE ROTATOR CAP INTAKE VALVES ARE INSTALLED PER LYCOMING SI1280D.