N577AL
Registered owner: ZIPLINE INTERNATIONAL INC, CA (owner ≠ operator)
Operators of this aircraft
Who operated this tail, and how firmly we know it.
| Operator | Role | Period | Basis |
|---|---|---|---|
| BRISTOW U.S. LLC (ALGA) | Operator | 2019-03-10 – 2019-03-10 | Operator named in NTSB report |
Accident & incident history
Maintenance disclosures
DURING LANDING, ENGINE CHIP LIGHT ILUMINATED, FOLLOWED BY A GRINDING NOISE THEN LOSS OF OIL PRESSURE. NR 8 BEARING FOUND DAMAGED.
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.
PERFORM FUNCTIONAL CHECK, FOUND O-RING ON DIFFERENTIAL VALVE FAILED, CAUSING INTERNAL FLUID BYPASS. REPLACED O-RING.
CORROSION AT TRANSMISSION MOUNTS BEYOND LIMITS.
ROD END WORN BEYOND REPAIRABLE LIMITS.
REPLACED TUBE DUE TO CORROSION BEYOND LIMITS.
FWD SEAT TRACK CRACKED.
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)
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.
FOUND BEARING DEFECTIVE, EXCESSIVE PLAY AND ROUGH/RATCHETING.
DURING COMPLIANCE OF ASB, FOUND TAIL ROTOR HEAD BEARINGS HAD EXCESSIVE AXIAL PLAY.
STARTING TO SEE A TREND OF NUMEROUS PITCH HORNS WITH CORROSION PROBLEMS, IN BARREL NUT BORE.
COOLER BLOWER BEARING IS ROUGH IN ROTATION.
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.
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.
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.
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.
T/M JOURNAL AND INNER RACE FOUND EXCESSIVE GALLING, CAUSING METAL CONTAMINATION.
FOUND EXCESSIVE GALLING ON PINION GEAR, SPALLING AND GALLING ON T/M GEAR. BOTH GEARS HAVE VERY UNUSUAL WEAR PATTERN. ENTRY MADE BY RNB
FOUND EXCESSIVE GALLING ON PINION GEAR, SPALLING AND GALLING ON T/M GEAR. BOTH GEARS HAVE VERY UNUSUAL WEAR PATTERN. ENTRY MADE BY RNB.
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.
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.
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.
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.
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.
TAILROTOR DRIVESHAFT BEARINGS, DURING DAILY INSPECTION, GREY GREASE FROM BEARINGS.
FOUND DURING ROUTINE MAINTENANCE. BLOWER HOUSING HAD CRACKED.
DURING 25-HOUR AD INSPECTION, FOUND FORWARD SEGMENT CRACKED ACROSS THE SPAN. (X)
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)
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)
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)
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)
DURING 25-HOUR AD INSPECTION, FORWARD SEGMENT CRACKED ACROSS TWO SPANS. 180 DEGREES OPPOSITE EACH OTHER. (X)
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)
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)
DURING DAILY INSPECTION, FOUND CRACK IN RADIUS.
CRACK IN RADIUS, POOR QUALITY CONTROL WHEN FABRICATING AND PART PUT IN LOAD ON INSTALLATION.
DURING DAILY INSPECTION FOUND SLAT SUPPORT, P/N 206-023-119-110, (LEFT SIDE, 2ND FROM INBOARD) CRACKED. REMOVED AND REPLACED CRACKED SUPPORT.
ON DAILY SERVICE CHECK, 4 MOUNTING BOLTS FOR VERTICAL FIN WERE FOUND TO HAVE LOST TORQUE.
ON DAILY SERVICE CHECK, 4 MOUNTING BOLTS FOR VERTICAL FIN WERE FOUND TO HAVE LOST TORQUE.