N58236

Part: CHANNEL — BROKEN (FIREWALL)

FOUND ON A DAILY INSPECTION 12/15/2002. CHANNEL HAS 12 INCHES AND 1 PIECE BROKEN OFF APPROXIMATELY 4 INCH. FABRICATE CHANNEL FROM THICKER MATERIAL.

Part: DISC PACK — CRACKED (TAIL ROTOR) · airframe 6,341 hrs

THE DISC PACK IS CRACKED.

Part: SHAFT — WORN (TRANSMISSION)

INPUT SHAFT, DURING 2500 HOUR OVERHAUL, SPLINES WORN BELOW MINIMUM LIMITS.

Part: DISC PACK — CRACKED (TAIL ROTOR)

ON TAIL ROTOR DRIVESHAFT, DURING 25 HOUR AD INSPECTION, CRACKED DISC.

Part: COVER — FAILED (SERVO)

SERVO WAS REMOVED FOR HOWLING NOISE IN FLIGHT, UNIT WAS DISASSEMBLED FOR OVERHAUL AND PN 41002521 COVER TO RETAIN VALVE, ID CORRODED AND VALVE SPRING WAS RUSTED IN HALF. IF RETAINER FAILED THE SERVO WOULD GO INTO BYPASS AND POSSIBLE HARDOVER CONDITION. COVER NEEDS TO BE MODIFIED TO ALLOW WATER TO DRAIN OR A BETTER BOOT NOT TO ALLOW WATER TO ENTER VALVE.

Part: RETAINER — CORRODED (BYPASS VALVE)

SERVO WAS REMOVED FOR HOWLING NOISE IN FLIGHT, UNIT WAS DISASSEMBLED FOR OVERHAUL AND PN 41002521 COVER TO RETAIN VALVE, ID CORRODED AND PN RS62 RETAINER TO RETAIN BYPASS VALVE SPRING WAS RUSTED IN HALF. IF RETAINER FAILED THE SERVO WOULD GO INTO BYPASS AND POSSIBLE HARD OVER CONDITION. COVER NEEDS TO BE MODIFIED TO ALLOW WATER TO DRAIN OR A BETTER BOOT NOT TO ALLOW WATER TO ENTER VALVE.

Part: DISC PACK — CRACKED (T/R DRIVE)

DURING 25 HOUR AD INSPECTION. DISC COUPLING CRACKED.

Part: PINION GEAR — GALLED (GEARBOX)

IN FLIGHT, CHIP LIGHT ILLUMINATED. UPON DISASSEMLBLY OF GEARBOX, FOUND EXCESSIVE GALLING ON GEAR TEETH OF PINION GEAR, GEAR TEETH. PINION GEAR EXCESSIVE GALLING DUE TO IMPROPER GEAR TEETH MESHING AND EXCESSIVE LOAD TO TORQUE AREA. INSURE GEAR HARDNESS AND MESHING OF GEAR TEETH BY VENDOR.

Part: TURBINE WHEEL — CORRODED (COMPRESSOR)

TURBINE RECEIVED IN SHOP FOR LOW POWER. UPON INSPECTION FOUND 1ST STAGE WHEEL BROKEN FROM SULPHADATION. REMOVED OUTER COMBUSTION CASE TO INSPECT FOR LOW POWER AND FOUND SULFADATION ON 1ST STAGE WHEEL. PIECES OF TRAILING EDGE WERE MISSING AND ONE BLADE WAS BROKEN. CAUSE FOR SULPHADATION IS UNKNOWN AT THIS TIME.

Part: BEARING — ROUGH (T/R DRIVE) · airframe 3,466 hrs

C/W THE INTENT OF HD 2000-02-12 BY INSPECTING OIL COOLER BLOWER D/S BEARINGS. AFT BEARING FOUND ROUGH RUNNING. (X)

Part: PULLEY — LOOSE (T/R DRIVE)

DURING AIRCRAFT RUN-UP FOLLOWING UNRELATED MAINTENANCE, MECHANIC NOTED AIR CONDITIONING COMP STOPPED TURNING WHEN AIR CONDITIONER SYSTEM WAS ACTIVATED. ACFT WAS SHUT DOWN AND MECH FOUND AIR COND DRIVE PULLEY LOOSE ON OIL COOLER BLOWER SHAFT. POSSIBLE CAUSE FOR THIS CONDITION WAS LOSS OF TORQUE BETWEEN DRIVE PULLEY FWD OIL COOLER BLOWER BEARING. DRIVE RING LOCK WAS TIGHT AND SAFTIED. SUBMITTER RECOMMENDED A POSSIBLE INCREASE IN TORQUE VALUE AND/OR AT THE VERY LEAST, A TORQUE CHECK REQUIREMENT OF 1 TO 5 HOURS AFTER INSTALLATION. (X)

Part: COMBUSTION CASE — CRACKED (FUEL NOZZLE)

HIGHER THAN NORMAL MGT INDICATION BY PILOT WAS REPORTED. INSPECTED AND PERFORMED TEST OF MEASURED GAS TEMPERATURE SYSTEM. NO ANOMALLY OBSERVED. UPON FURTHER INSPECTION FOUND SEAM WELDS AROUND FUEL NOZZLE BOSS CRACKED ALLOWING COOLING AIR TO ESCAPE.

Part: DISC PACK — DAMAGED (T/R DRIVE)

INSPECTING HELICOPTER PER AD 97-22-15. FOUND 2 EACH TAIL ROTOR DRIVE DISC BOLTS LOOSE AND DISC PACK BEYOND DAMAGE LIMIT. TT 789.0 HOURS.

Part: INDICATOR — FAILED (ENGINE TORQUE)

TORQUE INDICATOR WILL LOSE ALL POWER AT TIMES (INTERMITTENT). REPLACED INDICATOR.

Part: DISK PACK — CORRODED (T/R DRIVE)

INSPECTING HELICOPTER PER AD 97-22-15, FOUND TWO T/R DRIVE DISC PACKS BEYOND DAMAGE LIMIT. DAMAGE WAS DUE TO CORROSION. REPLACED DAMAGED PARTS.

Part: FRAHM ASSY — WORN (M/R)

RUBBER BOOT CAME LOOSE AND SPRINGS ROTATED INSIDE FRAHM. HELICOPTER HAD A 4 PER VIBRATION AND COULD NOT BE ELIMINATED. REPLACED FRAHM ASSY AND BALANCED HELICOPTER ROTOR SYSTEM TO ACCEPTABLE LEVELS.