N803MH

ATA 2150

Part: TENSIONER — CRACKED (AIR CONDITIONER)

DURING COMPRESSOR REPLACEMENT THE COMPRESSOR TENSIONING BRACKET WAS FOUND TO HAVE CRACKED ON ONE OF THE 2 ARMS AND SERVICEABLE REPLACEMENT PART INSTALLED. CLOSE EXAMINATION REVEALED THAT THE PARTS ARM SLOTS HAD BEEN WATER JETTED DURING MFG WHICH LEAVES A ROUGH SLOT SURFACE THAT SEEMS TO BE THE SOURCE OF THE STRESS RISER WHERE THE CRACK DEVELOPED. SUGGEST THAT THE MFG DRESSES AND POLISHES THE WATER JETTED SLOTS TO PREVENT CRACK DEVELOPMENT AND INCREASE MATERIAL THICKNESS TO IMPROVE PART SERVICEABILITY. (K)

ATA 2150

Part: TENSIONER — CRACKED (A/C COMPRESSOR)

DURING ROUTINE COMPRESSOR REMOVAL TO FACILITATE OTHER MAINTENANCE THE CRACKED TENSIONING ARM WAS DISCOVERED AND A NEW REPLACEMENT PART INSTALLED. SUSPECT METAL FATIGUE BUT THE SECOND TENSIONING ARM MAINTAINED UNIT FUNCTIONALITY HAD NO APPARENT DEFECT DEVELOPING. SUGGEST INSPECTING SLOTS OF THE TENSIONING ARMS IN DETAIL, WHENEVER REMOVING THE BELT TENSIONER, FOR CRACK DEVELOPMENT BEFORE ARM BREAKS. (K)

ATA 6220

Part: FREQ ADAPTER — CRACKED (M/R HUB)

DURING ROUTINE INSP AT THE 30 HOUR INTERVAL, A CRACK IN THE BLUE BLADE FREQ ADAPTER T/E SIDE WAS FOUND TO EXCEED THE MM LIMITATION OF 10 MM FOR CRACKS IN THE ELASTOMER. IAW MFG REQUIREMENTS ALL 3 ADAPTERS RENEWED. THIS IS A VERY COMMON FAILURE FOR A PART THAT HAS 3000 HOURS SERVICE LIFE LIMIT, SUGGEST REFORMULATION OF ELASTOMER. (K)

ATA 5302

Part: FITTING — CRACKED (TAILBOOM)

FITTING FOUND CRACKED DURING POST FLIGHT INSP. A NEW FITTING MATCH DRILLED AND INSTALLED. THIS IS A COMMON DEFECT FOR THIS PART AND OCCURS MULTIPLE TIMES ON SOME AC AND NEVER ON OTHERS FOR REASONS UNKNOWN. SOME SHIMMING IS SOMETIMES REQUIRED AND IF DONE POORLY THIS MAY AGGRAVATE THE CRACK DEVELOPMENT. SUGGEST THE PART DESIGN IS SUFFICIENT BUT A CHANGE OF MATERIAL TO A STRONGER METAL SUCH AS SS INSTEAD OF ALUMINUM ALLOY IS REQUIRED. (K)

ATA 5302

Part: FRAME — CRACKED (TAILBOOM)

DURING ROUTINE 100 HOUR INSPECTION THE CRACK WAS FOUND UTILIZING A BRIGHT LIGHT LOOKING AFT DOWN THE TAIL BOOM INTERIOR FROM THE TAILBOOM MOUNTED BATTER ACCESS DOOR. AS VIEWED FROM THE REAR, THE CRACK WAS LOCATED AT THE 9:00 POSITION OF THE TAIL BOOM FRAME, STARTING FROM A HI-LOCK FASTENER DRILL HOLE AND PROCEEDING AROUND THE FLANGE RADIUS AND OFF THE EDGE OF THE FRAME FLANGE UNDER THE TAILBOOM SKIN. THE MFG SUBSIDIARY WAS CONTACTED AND REPAIR SCHEME ENGINEERED AND ISSUED WITH FORM 8110-3 AND DETAILED INSTRUCTIONS WAS APPLIED TO THE CRACKED FRAME AS A MAJOR REPAIR WITH FORM 337 SUBMITTED FOR THE WORK PERFORMED. AS TO A CAUSE, POSSIBLY THE HI-LOC DRILLED HOLE HAD NOT BEEN DEBURRED ADEQUATELY DURING MFG AND DO

ATA 7230

Part: COMPRESSOR — SEIZED (ENGINE)

PILOT EXPERIENCED FLICKERING ENGINE CHIP LIGHT IN CRUISE FLIGHT AND AS A PRECAUTION PREPARED TO LAND AT FIRST SUITABLE LOCATION. ON APPROACH TO LANDING, CHIP LIGHT CAME ON STEADY AND COMPRESSOR STALL OCCURRED. SOME ROTOR SPEED DROP OCCURRED WITH LOW ROTOR WARNING SOUNDING IN THE PILOT HEADSET. AIRCRAFT WAS LANDED WITHOUT INCIDENT. ENGINE CONTINUED RUNNING UNTIL INCIDENT. ENGINE CONTINUED RUNNING UNTIL THROTTLE WAS SHUT DOWN WHEN GAS PRODUCER SPEED DECAYED, RAPIDLY. COMPRESSOR FOUND LOCKED UP. ENGINE RETURNED TO MFG FOR REPAIR. (WP19200505750) (K)

ATA 6510

Part: DRIVE SHAFT — LOOSE (TAIL ROTOR)

SUBSEQUENT TO THE DISCOVERY OF A VERY LOOSE COUPLING ON ANOTHER COMPANY AIRCRAFT, A SPECIAL INSPECTION OF OUR OTHER LIKE MODEL AIRCRAFT WAS INITIATED. THIS AIRCRAFT HAD TWO (2) OF THE SIX (6) SPECIAL ATTACHMENT RIVETS JUST BEGINNING TO LOOSEN WHEN A LITTLE MORE THAN NORMAL INSPECTION FORCE WAS APPLIED TO THE RIVET HEADS SQUARE SUPPORT BASE.

ATA 5410

Part: FASTENER — SHEARED (HOOK)

ON THE ENGINE FAIRING 1 OF 4) LATCHING HOOK OF THE FASTENER SHEARED AT HOOK BASE AND CRYSTALIZATION OF THE METAL AT THE BREAK SEEMED APPARENT. NO SIGNIFICANT WEAR NOTED BEFORE THE BREAK OCCURRED THIS IS A TITAIUM MATERIAL. SUGGEST USING STAINLESS STEEL.

ATA 1810

Part: FITTING — CRACKED (SUPPORT BEARING)

FITTING, RT CABIN ANTI-VIBRATOR TUNING HAMMER SUPPORT FITTINGS CRACKING IN RADIUS, BOTH FORWARD AND REAR FITTINGS CRACKING AT SAME TIME. THIS CAUSES NOTICEABLE INCREASE IN CABIN VIBRATION LEVELS. FITTINGS NEED LARGER RADIUS MACHINING OR TO BE OF GREATER STRENGTH.

ATA 1810

Part: FITTING — CRACKED (CABIN)

RT CABIN ANTI-VIBRATOR TUNING HAMMER SUPPORT FITTINGS CRACKING IN RADIUS, BOTH FORWARD AND REAR FITTINGS CRACKING AT SAME TIME. THIS CAUSES NOTICEABLE INCREASE IN CABIN VIBRATION LEVELS. FITTINGS NEED TO BE OF GREATER STRENGTH AND MACHINED RADIUS INCREASED.