N577AL

Part: CARTRIDGE — CLOGGED (BOOST PUMP)

ABOUT 10 MILES OFF OF BEACH LINE, THE BOOST PUMP CAME ON. PILOT TURNED ACFT AROUND AND RETURNED TO BASE. REPLACED LT BOOST PUMP CARTRIDGE.

Part: O-RING — LEAKING (T/R SERVO) · airframe 14,235 hrs

PERFORM FUNCTIONAL CHECK, FOUND O-RING ON DIFFERENTIAL VALVE FAILED, CAUSING INTERNAL FLUID BYPASS. REPLACED O-RING.

Part: MOUNT — CORRODED (M/R TRANSMISSION) · airframe 14,235 hrs

CORROSION AT TRANSMISSION MOUNTS BEYOND LIMITS.

Part: ROD END — WORN (PITCH CONTROL) · airframe 14,118 hrs

ROD END WORN BEYOND REPAIRABLE LIMITS.

Part: TUBE — CORRODED · airframe 14,118 hrs

REPLACED TUBE DUE TO CORROSION BEYOND LIMITS.

Part: SEAT TRACK — CRACKED (ZONE 200) · airframe 14,118 hrs

FWD SEAT TRACK CRACKED.

Part: INDICATOR — FAILED (ENGINE)

ON TAKEOFF, NG INDICATOR PEGGED OUT. RETURNED TO BASE AND NOTIFIED MAINTENANCE. REMOVED AND REPLACED INDICATOR WITH SERVICEABLE UNIT. FUNCTIONAL CHECK OK. IAW MM. (K)

Part: SPRING — MISALIGNED (FRAHM DAMPER)

SLIGHT VIBRATION ON LANDING, CHECKED ROTOR SYSTEM ON POST FLIGHT AND FOUND FRAHM DAMPER SPRING MISALIGNED. MAINTENANCE FOUND BROKEN SPRING IN FRAHM DAMPER. REMOVED AND REPLACED FRAHM DAMPER.

Part: BEARING — DEFECTIVE (MAIN ROTOR) · airframe 5,576 hrs

FOUND BEARING DEFECTIVE, EXCESSIVE PLAY AND ROUGH/RATCHETING.

Part: BEARING — WORN (T/R HEAD) · airframe 5,316 hrs

DURING COMPLIANCE OF ASB, FOUND TAIL ROTOR HEAD BEARINGS HAD EXCESSIVE AXIAL PLAY.

Part: PITCH HORN — CORRODED (TAIL ROTOR HEAD) · airframe 5,236 hrs

STARTING TO SEE A TREND OF NUMEROUS PITCH HORNS WITH CORROSION PROBLEMS, IN BARREL NUT BORE.

Part: BEARING — WORN (COOLER BLOWER) · airframe 5,222 hrs

COOLER BLOWER BEARING IS ROUGH IN ROTATION.

Part: FRAME — CRACKED (FUSELAGE)

DISCOVERED WHEN FRAME WAS REMOVED TO REMOVE AND REPLACE RIVETS ON TAILBOOM ATTACH FITTING. (RIGHT UPPER FITTING) IT HAS BECOME GOOD PRACTICE TO CHECK THIS AREA BECAUSE OF PAST PROBLEMS. THE FRAME HAS BEEN FOUND TO CRACK IN THIS SAME AREA ON ALL AIRCRAFT THAT THIS INSPECTION IS DONE. FRAME WAS CRACKED ABOVE MATING SURFACE OF RIGHT UPPER T/B ATTACH FITTING. MAYBE RADIUS THE EDGES OF ATTACH FITTING THAT MATE WITH FRAME.

Part: DOOR — CRACKED (ENGINE BAY)

LT ENGINE BAY DOOR LOWER RECTANGLE SCREEN IS CRACKED AND UPPER 2ND FRONT FORWARD SQUARE SCREEN CRACKED. LT AND RT ENGINE BAY DOORS. CHAFING OCCURRING ON LOWER AND FORWARD EDGE OF DOORS. LATCHES EXCESSIVE WEAR. FASTENERS ON FORWARD AFT EDGE HAS EXCESSIVE WEAR AROUND FASTENER HOLE. PULSING OF ROTOR WASH CAUSING STRESS ON LT DOOR.

Part: SKIN — CRACKED (FUSELAGE)

DURING DAILY INSPECTION, CRACKS, CORROSION, BROKEN SPOT WELDS, HINGES WORN OUT. SKIN CORROSION AT SPOT WELDS BECAUSE OF NON-ALCLAD MATERIAL. HEAVIER GAUGE MATERIAL ON STRINGERS NEEDED.

Part: BLADE — DAMAGED (COMPRESSOR)

WHILE HOVERING ONTO THE PARKING PAD, THE PILOT HEARD AN UNUSUAL SOUND FROM THE AIRCRAFT, UPON LANDING THE SUBSEQUENT INSPECTION REVEALED DAMAGE TO THE COMPRESSOR BLADE CAUSED BY A SMALL PIECE OF INTAKE SHELF INGESTED BY THE ENGINE. THE ENTIRE ENGINE WAS REMOVED AND REPLACED, ALSO THE INTAKE SHELF WAS REPLACED.

Part: BEARING — GALLED (GEARBOX) · airframe 4,769 hrs

T/M JOURNAL AND INNER RACE FOUND EXCESSIVE GALLING, CAUSING METAL CONTAMINATION.

Part: PINION GEAR — GALLED (GEARBOX) · airframe 4,769 hrs

FOUND EXCESSIVE GALLING ON PINION GEAR, SPALLING AND GALLING ON T/M GEAR. BOTH GEARS HAVE VERY UNUSUAL WEAR PATTERN. ENTRY MADE BY RNB

Part: GEAR — GALLED (GEARBOX) · airframe 4,769 hrs

FOUND EXCESSIVE GALLING ON PINION GEAR, SPALLING AND GALLING ON T/M GEAR. BOTH GEARS HAVE VERY UNUSUAL WEAR PATTERN. ENTRY MADE BY RNB.

Part: PINION GEAR — WORN (ENGINE)

ENGINE WAS REMOVED DUE TO CHIP LIGHT. GEARBOX WAS DISASSEMBLED TO FIND SOURCE OF METAL. FOUND EXCESSIVE GALLING ON PINION GEAR, SPALLING AND GALLING ON T/M GEAR. BOTH GEARS HAVE VERY UNUSUAL WEAR PATTERN. ASSURE PROPER MESHING AND MACHINING OF GEAR TEETH AT FACTORY.

Part: PINION GEAR — WORN (ENGINE)

ENGINE WAS REMOVED DUE TO CHIP LIGHT. GEARBOX WAS DISASSEMBLED TO FIND SOURCE OF METAL. FOUND EXCESSIVE GALLING ON PINION GEAR, SPALLING AND GALLING ON T/M GEAR. BOTH GEARS HAVE VERY UNUSUAL WEAR PATTERN. ASSURE PROPER MESHING AND MACHINING OF GEAR TEETH AT FACTORY.

Part: BEARING — GALLED (TM BEARING)

ENGINE WAS REMOVED DUE TO CHIP LIGHT. GEARBOX WAS DISASSEMBLED TO FIND SOURCE OF METAL. UPON REMOVAL OF T/M JOURNAL AND INNER RACE FOUND EXCESSIVE GALLING, CAUSING METAL CONTAMINATION. ASSURE BEARINGS AND INNER RACE CAN WITH STAND HIGH LOADING CAPACITY.

Part: DISC PACK — BROKEN (TAIL ROTOR)

DURING 25 HOUR AD INSPECTION, BROKEN DISC IN DISC PACK. ALLOW TAIL ROTOR DRIVE SHAFT TO FLOAT SO DISC PACKS DO NOT FLEX AS MUCH OR AS OFTEN.

Part: BEARING — MAKING METAL (M/R GEARBOX)

METAL WAS FOUND ON CHIP PLUGS, ENGINE AND GEARBOX DISASSEMBLED FOR INSPECTION. FOUND CAUSE FOR METAL DUE TO INNER RACE GALLING ON T/M JOURNAL BEARING, CAUSING METAL CONTAMINATION THROUGHOUT GEARBOX.

Part: BEARING — DAMAGED (T/R DRIVESHAFT)

TAILROTOR DRIVESHAFT BEARINGS, DURING DAILY INSPECTION, GREY GREASE FROM BEARINGS.

Part: HOUSING — CRACKED (BLOWER)

FOUND DURING ROUTINE MAINTENANCE. BLOWER HOUSING HAD CRACKED.

Part: DISC PACK — CRACKED (TAIL ROTOR)

DURING 25-HOUR AD INSPECTION, FOUND FORWARD SEGMENT CRACKED ACROSS THE SPAN. (X)

Part: HANGER ASSY — DAMAGED (OIL COOLER) · airframe 2,604 hrs

ON FINAL APPROACH, PILOT FELT A GRINDING IN THE FLIGHT CONTROLS. POST-FLIGHT INSPECTION REVEALED FORWARD OIL COOLER BLOWER BEARING FAILURE. FORWARD BEARING DISINTEGRATED (FAILED) IN THE HANGER AND THE HANGER WAS DAMAGED. (X)

Part: BEARING — FAILED (COOLER BLOWER)

ON FINAL APPROACH, PILOT FELT A GRINDING IN THE FLIGHT CONTROLS. POST-FLIGHT INSPECTION REVEALED FORWARD OIL COOLER BLOWER BEARING FAILURE. BEARING DISINTEGRATED (FAILED). (X)

Part: BEARING — FAILED (COOLER BLOWER) · airframe 2,604 hrs

ON FINAL APPROACH, PILOT FELT A GRINDING IN THE FLIGHT CONTROLS. POST-FLIGHT INSPECTION REVEALED FORWARD OIL COOLER BLOWER BEARING FAILURE. BEARING DISINTEGRATED (FAILED). (X)

Part: SHAFT — FAILED (OIL COOLER)

ON FINAL APPROACH, PILOT FELT A GRINDING IN THE FLIGHT CONTROLS. POST-FLIGHT INSPECTION REVEALED FORWARD OIL COOLER BLOWER BEARING FAILURE. FORWARD BEARING DISINTEGRATED (FAILED) AND DAMAGED SHAFT. (X)

Part: DISC PACK — CRACKED (NR 3)

DURING 25-HOUR AD INSPECTION, FORWARD SEGMENT CRACKED ACROSS TWO SPANS. 180 DEGREES OPPOSITE EACH OTHER. (X)

Part: TRANSMISSION — CORRODED (MAIN ROTOR)

AT DISASSEMBLY FOR TRANSMISSIONS FIRST OVERHAUL, FOUND CORROSION IN BORE OF MOUNTING SPLINDLE. CORROSION IN BORE OF CHIP DETECTOR ASSY. CORROSION ON INPUT FLANGE. (X)

Part: DRIVE SHAFT — VIBRATION (TRANSMISSION) · airframe 2,154 hrs

DURING FLIGHT, A VIBRATION WAS NOTICED. FOUND A SECTION APPROXIMATELY 3 INCHES LONG HAD BROKEN OFF FROM ONE OF THE FLEX FRAMES. THE SECTION PUNCTURED THE ROOF PANEL AND NICKED THE FUEL VENT LINE. (X)

Part: SUPPORT BRACKET — CRACKED (TAILBOOM)

DURING DAILY INSPECTION, FOUND CRACK IN RADIUS.

Part: SUPPORT — CRACKED (TAILBOOM)

CRACK IN RADIUS, POOR QUALITY CONTROL WHEN FABRICATING AND PART PUT IN LOAD ON INSTALLATION.

Part: SUPPORT — CRACKED (HORIZ STABILIZER)

DURING DAILY INSPECTION FOUND SLAT SUPPORT, P/N 206-023-119-110, (LEFT SIDE, 2ND FROM INBOARD) CRACKED. REMOVED AND REPLACED CRACKED SUPPORT.

Part: BOLT — LOOSE (VERTICAL FIN)

ON DAILY SERVICE CHECK, 4 MOUNTING BOLTS FOR VERTICAL FIN WERE FOUND TO HAVE LOST TORQUE.

Part: BOLT — LOOSE (VERTICAL FIN)

ON DAILY SERVICE CHECK, 4 MOUNTING BOLTS FOR VERTICAL FIN WERE FOUND TO HAVE LOST TORQUE.