N817MH

ATA 7250

ON SHORT FINAL TO LANDING, ACFT CAUTION WARNING PANEL ENGINE CHIP LIGHT ILLUMINATED. ENGINE WAS SHUTDOWN NORMALLY, INSPECTION OF THE CHIP DETECTORS, METAL WAS FOUND THAT APPEARED TO BE MORE THAN TYPICAL. CLEANED THE CHIP PLUGS, A 10 MINUTE PENALTY GROUND RUN WAS PERFORMED. RECHECKED CHIP PLUGS ON SHUTDOWN REVEALED NO UNUSUAL METAL GENERATION. FOLLOWING A SEVERAL MINUTE HOVER CHECK, WITH NO FURTHER CHIP LIGHT ILLUMINATION, ACFT DEPARTED FOR THE 10 MINUTE FLIGHT LEG TO OUR REMOTE FUELING STATION. ON SHORT FINAL, ENGINE CHIP LIGHT ILLUMINATED AGAIN. A NORMAL LANDING AND ENGINE SHUTDOWN WAS PERFORMED. ON FURTHER INSPECTION OF CHIP DETECTORS, DETERMINED THAT THE METAL CHIPS GENERATED EXCEEDED THE ALLOWABLE MM SPECS. ENGINE REMOVED AND MODULES RETURNED TO VENDOR. TEARDOWN INSPECTION BY THE VENDOR, DETERMINED THAT THE AFT BEARING OF THE POWER TURBINE/MODULE 4 HAD FAILED. METAL GENERATED, ALSO CONTAMINATED THE MODULE 5.

ATA 5302

DURING REPAIR OF ADJACENT TAILCONE SKIN CRACKS A DETAILED VISUAL INSP OF THE UPPER RT HORIZONTAL STABILIZER SPAR REVEALED A CRACK RADIATING FROM A SINGLE STABILIZER ATTACHMENT FITTING, ATTACHMENT BORE AROUND THE SPAR'S FLANGE RADIUS AND ENDING AT A RIVET BORE UNDER THE TAIL CONE SKIN. OVERALL CRACK LENGTH 1.1 INCH.

ATA 5302

TAILBOOM CONE SKIN AND SKIN DOUBLER CRACKS WERE DISCOVERED DURING ROUTINE 100 HOUR INTERVAL IMPS LOCATED ADJACENT TO THE RT, AFT, LWR HORIZONTAL STABILIZER'S TAILBOOM THROUGH MOUNT CUTOUT.

ATA 3340

NAV LIGHT ASSY, FOUND INOPERATIVE DURING ROUTINE POST FLIGHT INSPECTION, INSTALLED NEW REPLACEMENT, OPERATIONAL CHECK WAS CORRECT. THIS PART HAS HAD VIBRATION RELATED FAILURES IN OUT FLEET ON SEVERAL OCCASIONS. (K)

ATA 5350

FOUND CRACKS RADIATING FROM A SINGLE SCREW BORE DURING ROUTINE INSPECTION. INSTALLED NEWLY REPAIRED AND PAINTED ASSY. FOLLOWING DOUBLER INSTALLATION AT SCREW BORE POSITIONS. THIS PART HAS HAD A HISTORY OF SIMILAR CRACK DEVELOPMENT UNTIL DOUBLERS WERE APPLIED. CURRENTLY NEW ACFT ARE DELIVERED FROM THE FACTORY WITH DOUBLER INSTALLED AT THESE SCREW BORE POSITIONS. (K)

ATA 5344

DURING ROUTINE INSPECTION, HINGE WAS FOUND CRACKED THROUGH A SCREW MOUNTING BORE TO THE METALS EDGE. THIS IS A VERY COMMON FAILURE FOR THIS PART. (K)

ATA 5344

DURING ROUTINE INSPECTION A CRACK WAS FOUND IN THE HINGE MOUNTING FLANGE RADIATING FROM THE OUTERMOST LT ATTACHMENT SCREW BORE. THIS IS A VERY COMMON FAILURE FOR THIS PART. (K)

ATA 6220

DURING ROUTINE 100 HOUR INSPECTION, A CRACK IN THE BLUE BLADE ELASTOMER WAS FOUND ON THE T/E LWR IB SURFACE RADIATING FROM THE INSPECTION BORE. THIS CRACK HAD REACHED THE MM LIMITATION OF 10MM IN TOTAL LENGTH. THIS IS A VERY COMMON FAILURE FOR A PART WITH A NEWLY PUBLISHED 20000 HOUR LIVE LIMIT. THE ORIGINAL LIFE LIMIT WAS 3000 HOURS WHICH NONE OF THESE PARTS HAVE EVER LASTED. MFG EXPLANATION WAS THAT THE LIMIT WAS FOR THE METAL COMPONENTS OF THE PART. THE ELASTOMER FORMULATION OF THE ORIGINAL PN WHICH HAD BEEN REPLACED BY THE CURRENT PN ALMOST NEVER FAILED. MFG HAS BEEN NOTIFIED OF BOTH THESE DETAILS WITH NO ACTION TAKEN. (K)

ATA 5344

DURING ROUTINE 100 HOUR INSP, A CRACK IN THE HINGE OF THE ENGINE FAIRING WAS FOUND RADIATING FROM THE 2ND HOLE FROM ONE END OF THE HINGE WITH THE CORNER HAVING SEPARATED FROM THE HINGE FROM CRACKS EMANATING FROM THE 1ST HOLE. THIS IS A COMMON FAILURE FOR THIS PART. THE SURFACE UNDER THE HINGE IS UNEVEN AND GIVES UNEVEN SUPPORT TO THE HINGE WHEN BOLTED DOWN. SUGGEST USING A STRONGER MATERIAL SUCH AS STAINLESS STEEL FOR THE HINGE OR IMPROVING THE SURFACE CONTOUR AND STRENGTH OF THE FAIRING HINGE MOUNTING SURFACE. (K)

ATA 6322

PILOT REPORTED BLOWER VERY NOISY/GROWLS IN OPERATION. CLOSER EXAMINATION REVEALED VERY ROUGH SHAFT BEARING. A NEW REPLACEMENT MOTOR WAS INSTALLED. THIS BLOWER MOTOR IS USUALLY VERY RELIABLE IF A BIT NOISY IN NORMAL OPERATION. LIKELY CAUSE IS POOR QUALITY OR INSUFFICIENT GREASING OF THE BEARINGS BY MFG. (K)