N417AL

Part: GEAR — SPALLED (GEARBOX) · airframe 7,894 hrs

FOUND SPALLED GEAR TEETH ON GEAR. REPLACED W/NEW PART.

Part: GEAR — SPALLED (M/R GEARBOX) · airframe 7,894 hrs

FOUND SPALLED GEAR TEETH ON GEAR. REPLACED W/NEW PART.

Part: UNIVERSAL — WORN (MAIN ROTOR) · airframe 6,789 hrs

BEARING WORN AND RATCHETY.

Part: BEVEL GEAR — MAKING METAL (TRANSMISSION)

TRANSMISSION MAKING METAL. BEVEL GEAR CRACKED FROM BOLT HOLE.

Part: BEARING — DAMAGED (T/R DRIVESHAFT)

ON THE 2ND SHUT DOWN OF THE DAY, LOUD NOISES AND EXCESSIVE VIBRATION WERE NOTED. FORWARD BEARING ON THE NR 2 TAILROTOR DRIVESHAFT, (OIL COOLER BLOWER) HAD AN UNCONTAINED FAILURE. BLOWER DECK AND SUPPORTING STRUCTURE CRACKED AFT ENGINE FIREWALL AND IMPELLER HOUSING.

Part: PINION GEAR — MAKING METAL (GEARBOX)

DISASSEMBLED GEARBOX DUE TO METAL IN OIL. CLEANED AND INSPECTED, FOUND EXCESSIVE GALLING ON PINION GEAR AND TORQUEMETER GEAR TEETH. PINION GEAR HAD EXCESSIVE GALLING ON GEAR TEETH DUE TO IMPROPER MESHING OF T/M AND PINION GEARS. SECONDARY DAMAGE: T/M GEAR PN 23071895, SN NN146407, TT 591.3 HOURS, SPALLING AND GALLING ON GEAR TEETH. (X)

Part: DISC PACK — CRACKED (TAIL ROTOR)

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

Part: DISC PACK — CRACKED (TAIL ROTOR)

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

Part: DUCT — CRACKED (OIL COOLER)

UPON DAILY INSPECTION, CRACKS IN CORNERS CAUSED BY IHERENT VIBRATIONS. (X)

Part: GEAR — DAMAGED (GEARBOX)

DISASSEMBLED, CLEANED, AND INSPECTED. FOUND SPALLING AND GALLING ON GEAR TEETH. TM GEAR HAS EXCESSIVE SPALLING AND GALLING ON GEAR TEETH POSSIBLY DUE TO IMPROPER MESHING OF TM AND PINION GEARS. SECONDARY DAMAGE. PINION GEAR, PN 6893672, SN 77723, TT 1,196.5, SPALLING AND GALLING ON GEAR TEETH. (X)

Part: BEARING — WORN (PITCH LINK)

ON DAILY INSPECTION, FOUND OUTER RACE OF PITCH CHANGE LINK SPHERICAL BEARING WORN THROUGH BY BALL ALLOWING LINK TO CONTACT PITCH HORN CAUSING DAMAGE TO BOTH REQUIRING SCRAPPING.

Part: DISC PACK — CRACKED (T/R DRIVE)

25 HOUR AD 97-234-17 PTS A, B, AND E. BOTH DISC PACKS HAD NR 1 DISC CRACKED. NR 1 DISC PER DISC PACK CRACKED, NR 4 AND N4 7 T/R DRIVE SHAFT.

Part: DISC — CRACKED (TAIL ROTOR)

SCHEUDLED INSPECTION FOUND DISC PACK CRACKED.

Part: BLADE — DELAMINATION (M/R)

FIFTY HOUR INPSECTION FOUND M/R BLADE PTTING COMPOUND DELAMINATION AT OUTBOARD WEIGHT POCKET.

Part: BLADE — DELAMINATED (M/R)

FIFTY HOUR INSPECTION FOUND M/R BLADE POTTING COMPOUND DELAMINATION AT OUTBOARD WEIGHT POCKET.

Part: BLADE — DELAMINATED (M/R)

FIFTY HOUR INSPECTION FOUND M/R BLADE POTTING COMPOUND DELAMINATED AT OUTBOARD WEIGHT POCKET.

Part: BLADE — DELAMINATED (M/R)

FIFTY HOUR PHASE INSPECTION FOUND M/R BLADE POTTING COMPOUND DELAMINATING AT OUTBOARD WEIGHT POCKET.

Part: SUPPORT — CRACKED (HORIZ STAB RT)

AFTER BEING NOTIFIED THAT ONE OTHER AIRCRAFT IN FLEET HAD LOST ITS SLAT, C/W A VISUAL INSPECTION AND FOUND THE HORIZONTAL STABILIZER SLAT SUPPORT ON THE RT SIDE CRACKED. TWO EACH. TWO OUTBOARD SLAT SUPPORTS CRACKED IN RADIUS ARE OF SUPPORT TO HORIZONTAL STABILIZER MOUNTING AREA.

Part: SUPPORT — CRACKED (HORIZ STAB)

AFTER BEING NOTIFIED THAT ONE OTHER AIRCRAFT IN FLEET HAD LOST ITS SLAT, SUBMITTER C/W VISUAL INSPECTION AND FOUND THE HORIZONTAL STABILIZER SLAT SUPPORT ON THE RT SIDE CRACKED. TWO EACH. TWO OUTBOARD SLAT SUPPORTS CRACKED IN RADIUS AREA OF SUPPORT TO HORIZONTAL STABILIZER MOUNTING AREA.

Part: SKIN — DENTED (TAILBOOM)

DURING PRE-FLIGHT INSPECTION, FOUND SHARP DENT IN LT SIDE OF TAILBOOM SKIN APPROXIMATELY 34.8750 INCH FORWARD OF THE AFT END OF THE TAILBOOM CAN AND APPROXIMATELY 2.25 INCH IN LENGTH. THE DENT APPEARS TO HAVE BEEN CAUSED BY A TAIL ROTOR BLADE STRIKING THE TAILBOOM WHILE THE ROTORS WERE IN MOTION.

Part: DISK PACK — CRACKED (T/R DRIVE)

DURING C/W 25-HOUR AD 97-24-17, PART A, B, AND E, FOUND ONE LAMINATE ON AFT SIDE OF NR 7 DISK PACK, P/N 406-040-340-101, CRACKED.

Part: BLOWER HOUSING — CRACKED (OIL COOLER)

BLOWER REMOVED BECAUSE OF ROUGH BEARINGS. HOUSING ALSO CRACKED. SHEET METAL HOUSING CRACKED AT RIVETED EDGE WHERE HOUSING ATTACHES TO 407-062-021-101 OIL COOLER DUCT ASSEMBLY. SUBMITTER SUGGESTED THAT POSSIBLY A POOR FIT PUTTING STRAIN ON SHEET METAL WHEN ATTACHED TO DUCT.

Part: DISC PACK — CRACKED (T/R DRIVE)

C/W OF AD 97-22-15, FOUND T/R DRIVE COUPLING DISC PACK AFT LAMINATE 'ONE' CRACKED BETWEEN NR 6 AND NR 7. SUBMITTER RECOMMENDS FLOATING DRIVESHAFTS SIMILAR TO THE BELL 206 SERIES.

Part: COUPLING DISK — CRACKED (NR 7 T/R DRIVE)

DURING DAILY INSPECTION, FOUND NR 7 TAIL ROTOR DRIVESHAFT FORWARD LAMINATE CRACKED.

Part: DISC PACK — CRACKED (NR 7 T/R CPLNG)

DAILY CHECK NOTAM 51A-97 OCCURRED DURING NORMAL FLIGHT, FOUND NR 7 COUPLING CRACKED 2 LAMINATES NR 1 AND NR 2 PACK HAS TEN DISCS.

Part: BEARING — ROUGH (T/R DRIVE)

NR 2 SHAFT REMOVED FROM AIRCRAFT DUE TO ROUGH BEARING. FOUND BEARING 406-040-339-105 INSTALLED AT AIRCRAFT HOURS 808.0 HOURS ROUGH. ALSO, SHAFT 406-040-320-101, TT 1410.8 HOURS. FORWARD SPLINES WORN AND CORRODED BEYOND LIMITS.

Part: COUPLING DISK — CRACKED (NR 7 T/R DRIVE)

DURING C/W MAINTENANCE NOTAM 51A-97, FOUND 2 EACH LAMINATES CRACKED ON NR 7 TAIL ROTOR DRIVESHAFT COUPLING.

Part: DISK — CRACKED (T/R DISK PACK)

SCHEDULED INSPECTION FOUND DISK PACK DISK CRACKED. THREE REPORTS RECEIVED DATED 9-24-97 ON T/R DISK PACK DISK CRACKED.

Part: DISK — CRACKED (T/R DISK PACK)

SCHEDULED INSPECTION FOUND DISK PACK DISK CRACKED. REMOVED AND REPLACED. THREE REPORTS RECEIVED DATED 9-24-97 ON T/R DISK PACK DISK CRACKED.

Part: COUPLING DISK — CRACKED (NR 7 T/R DRIVE)

DURING COMPLIANCE OF MAINTENANCE NOTAM NR 51A-97, FOUND NR 7 TAIL ROTOR DRIVESHAFT COUPLING LAMINATE CRACKED (1).

Part: COUPLING DISK — CRACKED (NR 3 T/R DRIVE)

DURING 50-HOUR PMI, FOUND NR 3 TAIL ROTOR DRIVESHAFT COUPLING LAMINATE CRACKED (1).

Part: COUPLING DISK — CRACKED (NR 6 T/R DRIVE)

DURING 50-HOUR PMI, FOUND NR 6 TAIL ROTOR DRIVESHAFT DISC LAMINATE CRACKED (1).

Part: COUPLING DISK — CRACKED (NR 7 T/R DRIVE)

DAILY INSPECTION FOUND NR 7 TAIL ROTOR DRIVESHAFT COUPLING CRACKED (1) LAMINATE.

Part: COUPLING DISK — CRACKED (NR 7 T/R DRIVE)

DURING 50-HOUR PMI, FOUND NR 7 TAIL ROTOR DRIVESHAFT COUPLING CRACKED (1) LAMINATE.

Part: BEARINGS — WORN (T/R YOKE)

PRE-FLIGHT CHECK FOUND 2 EACH BEARINGS 406-312-100-101 INNER RACES WORN BEYOND LIMITS. ONE EACH OUTER RACE CRACKED. BEARINGS LOCATION INBOARD ON YOKE.

Part: DISC PACK — CRACKED (T/R DRIVE)

DURING 50-HOUR PREVENTIVE MAINTENANCE INSPECTION, FOUND T/R DRIVE SHAFT DISC PACK CRACKED.

Part: DISC PACK — CRACKED (T/R DRIVE)

DURING 50-HOUR PREVENTIVE MAINTENANCE INSPECTION, FOUND T/R DRIVE SHAFT DISC PACK CRACKED.

Part: DISC PACK — CRACKED (T/R)

DURING 50-HOUR PREVENTIVE MAINTENANCE INSPECTION, FOUND T/R DRIVE SHAFT DISC PACK CRACKED.

Part: DISC PACK — CRACKED (FWD END)

DURING 50-HOUR PMI, FOUND FORWARD DISC PACK CRACKED ON NR 7 T/R DRIVESHAFT.

Part: COUPLING — DISC CRACKED (SHAFT)

INSPECTION FOUND TWO OUTER DISCS CRACKED. ONE CRACKED INTO 2 PIECES, ONE CRACKED FROM MIDDLE OF DISC TO INNER EDGE.