N494BC
Registered owner: HYANNIS AIR SERVICE INC, MA (owner ≠ operator)
Operators of this aircraft
Who operated this tail, and how firmly we know it.
| Operator | Role | Period | Basis |
|---|---|---|---|
| HYANNIS AIR SERVICE INC. (HYIA) | Certificate holder | — | Matched by certificate designator |
Accident & incident history
No NTSB accidents or incidents on file for this aircraft.
Maintenance disclosures
DURING INSPECTION A CRACK WAS VISUALLY NOTED ON THE LEFT HAND CROSSOVER BEAM (OEM 5654104-11). THIS CRACK IS LOCATED ON THE AFT FACE OF THE BEAM AT APPROXIMATE LWS 81.62. THE CRACK IS APPROXIMATELY .500 INCHES LONG AND .250 INCHES DOWN FROM THE TOP EDGE OF THE BEAM. THIS BEAM HAS BEEN REPLACED USING SERVICEABLE PARTS.
PILOT REPORTED LEFT ENGINE CYLINDER TEMP INDICATIONS WERE IN THE RED ON TAXI OUT. MAINTENANCE INSPECTED AND FOUND THE POSITIVE WIRE TO THE ALTERNATOR SHORTED INTO THE ADEL CLAMP AT THE CROSSOVER BEAM. THIS CAUSED DAMAGE TO THE SURROUNDING WIRE HARNESS AND HOSES. REPAIRS ARE IN PROCESS.
DURING MAINTENANCE A SPOT OF CORROSION WAS VISUALLY IDENTIFIED ON THE LEFT HAND UPPER FORWARD WING ATTACH FITTING. IT IS LOCATED ON THE BOTTOM FACE OF THE UPPER HORIZONTAL LEG OF THE FITTING AND MEASURES APPROXIMATELY .555 INCHES LONG, .300 INCHES WIDE, AND .020 INCHES DEEP. THIS CORROSION IS CONSISTENT WITH OTHERS FOUND USING A VISUAL INSPECTION TECHNIQUE. THIS FITTING WILL BE REPLACED USING NEW PARTS.
NOSE GEAR LIGHT DID NOT ILLUMINATE ON EXTENSION, AIRCRAFT LANDED WITH GEAR UNLOCKED, GEAR COLLAPSED ON LANDING. NO INJURIES. INSPECTED AIRCRAFT AND FOUND HYDRAULIC PRESSURE LINE IN RIGHT WING CRACKED AND BLOWDOWN BOTTLE DID NOT DISCHARGE.
DURING MAINTENANCE A CRACK WAS VISUALLY IDENTIFIED ON THE AFT SIDE OF THE RIGHT NACELLE CROSSOVER BEAM (P/N: 5654104-12). THIS CRACK MEASURES APPROXIMATELY 1.302 INCHES IN LENGTH, AND BEGINS AT THE OUTBOARD TURBO BRACKET MOUNTING HOLE ON THE AFT FACE OF THE BEAM. THIS CRACK IS CONSISTENT WITH OTHERS FOUND IN THIS AREA AND IS NOT VISIBLE WITH THE TURBO MOUNTING BRACKET INSTALLED. THIS BEAM WILL BE REMOVED AND REPLACED USING NEW PARTS.
DURING X-RAY INSPECTION OF THE RIGHT HAND INBOARD ENGINE BEAM TO SATISFY THE REQUIREMENT OF AD 97-26-16, A CRACK WAS IDENTIFIED TRAVELING IN A DIRECTION TRANSVERSE TO THE LENGTH OF THE BEAM ACROSS THE TOP OF THE ENGINE BEAM ASSEMBLY. THIS CRACK IS LOCATED APPROXIMATELY 14.219 INCHES AFT OF THE FRONT EDGE OF THE ENGINE BEAM IN THE AREA OF THE AFT ENGINE MOUNT BRACKETâS, FORWARD ATTACH POINT. THIS CRACK WAS NOT VISIBLE DUE TO THE INSTALLATION OF SK414-19B INSTALLED TO SATISFY MEB85-03R2, MODIFYING THE AFT ENGINE BEAM MOUNTS. THIS CRACK IS NOT LOCATED IN AN AREA OF INSPECTION DESCRIBED IN AD2015-07-03. AFTER REMOVAL OF THE SERVICE KIT DOUBLERS, VISUAL CONFIRMATION OF THE CRACK WAS MADE AND THE CRACK WAS MEASURED AT 1.592 IN AND TRAVELING UP THE LEFT FACE OF THE BEAM, CONTINUING ACROSS THE TOP OF THE BEAM THROUGH BOTH RADII, APPROXIMATELY 1.470 INCHES, AND FINALLY TRAVELLING DOWN THE RIGHT FACE OF THE BEAM APPROXIMATELY 2.157 INCHES.  THIS CRACK IS IN EXCESS OF ALLOWABLE LIMITS PROVIDED BY SK414-19B SEC 1, PARAGRAPH 2, PART C OF SK414-19B. UPON REMOVAL OF THE SERVICE KIT DOUBLERS, THE QUALITY OF WORKMANSHIP FOR THE INSTALLATION CAN BEST BE DESCRIBED AS âPOORâ, WITH MULTIPLE ELONGATED HOLE LOCATIONS WITH POOR EDGE DISTANCE AND HOLES THAT HAD NOT BEEN DEBURRED. THIS BEAM WAS LAST RADIOGRAPHED 9,454 FLIGHT HOURS PRIOR TO THIS EVENT. THE BEAM ASSEMBLY WILL BE REPLACED USING NEW PARTS, AND WE ARE PROACTIVELY EVALUATING OPTIONS FOR IMPROVED INSPECTION PROCEDURES TO FACILITATE THE IDENTIFICATION OF POTENTIAL FUTURE DISCREPANCIES.
DURING A ROUTINE INSPECTION, A CRACK WAS DISCOVERED IN THE RT OUTBOARD NACELLE FITTING. THE CRACK WAS FOUND ON THE INBOARD SIDE OF THE FITTING, JUST FORWARD OF THE SPAR STRAP. THE CRACK MEASURED .098 IN LENGTH.
DURING A ROUTINE INSPECTION, THREE CRACKS WERE FOUND ON THE LT OUTBOARD NACELLE FITTING. THESE CRACKS WERE DISCOVERED ON THE INBOARD SIDE OF THE FITTING, JUST FORWARD OF THE SPAR STRAP. THE CRACKS MEASURED .088, .097, AND .155 IN LENGTH.
CYLINDER REMOVED DUE TO LOW COMPRESSION AT INSPECTION; EXHAUST VALVE DISPLAYS EVIDENCE OF HEAT DAMAGE.
PILOT REPORTED THE LT WING LOCKER OPENED DURING FLIGHT. INSPECTED THE LT WING LOCKER DOOR & LATCH ASSEMBLY WITH NO DEFECT NOTED. OPERATIONS CHECKED GOOD.
LOST BRAKING FOR A FEW SECONDS ON LANDING ROLLOUT. FIRST ON CO-PILOT SIDE THEN ON PILOT SIDE. INSPECTED BRAKE LINING & PADS ON LT & RT SIDE. INSPECTED FOR LEAKS, NO DEFECTS NOTED, SERVICED BOTH BRAKE MASTER CYLINDERS WITH FLUID. OPERATIONS CHECKED GOOD.
PILOT REPORTED RPM LOSS ON THE RT ENG DROPPED FROM 2300 TO 2000 RPM. WOULD NOT CHANGE WHEN MOVING PROP LEVER. SECURED PROP LINKAGE IAW MM CH 61-20-00. OPERATIONALLY CHECKED GOOD.
UPON REMOVAL OF LT MLG HYD EXTEND & RETRACT ACTUATOR TO FACILITATE OTHER MAINTENANCE, A HOLE WAS DISCOVERED IN THE LT WING FWD SPAR WEB. THE HOLE IS LOCATED AT APPROX LT WS 91.62 & WAS CREATED WHEN COTTER PIN USED TO SAFETY HARDWARE STACK UP AT UPPER MLG ACTUATOR ATTACH POINT CHAFED THROUGH WEB. THE HOLE MEASURES .13 HIGH BY .253 ACROSS & IS LOCATED JUST BELOW VERTICAL LEG OF UPPER FWD WING SPAR CAP. REPAIR AREA IAW EITHER OEM OR DER SUPPORTED REPAIR DEFINITION. A SUPPLEMENT WILL BE SUBMITTED WITH THIS SDR TO FURTHER ILLUSTRATE DAMAGE POINT.
PILOT REPORTED THAT AFTER TAKEOFF, A VIBRATION WAS FELT THROUGHOUT THE AIRFRAME. ELECTED TO RETURN TO DEPARTURE. ALL PANELS AND DOORS WERE INSPECTED FOR SAFETY AND SECURITY AS A PROBABLE CAUSE OF VIBRATION, NO DEFECTS NOTED. INSPECTED ENGINES. RT ENGINE SPARKPLUGS WERE FOUND TO BE WORN. ALL TWELVE SPARK PLUGS WERE R & R. ACFT OPS CHECKED GOOD.
AT SCHEDULED INSPECTION, NLG DRAG BRACE, PN 5142002-5, WAS FOUND TO BE CRACKED IN THE AREA OF NLG ACTUATOR ATTACH POINT. METHOD OF INSPECTION WAS DYE PENETRANT. THIS CRACK WAS FOUND TO BE WITHIN ALLOWABLE LIMIT OF MEB91-11R1. THIS UNIT HAS BEEN REPAIRED IAW PROCEDURE OUTLINED IN MEB941-11R1 & RETURNED TO SERVICE.
AT SCHEDULED INSPECTION, NLG DRAG BRACE, PN 5142002-5, WAS FOUND TO BE CRACKED IN THE AREA OF NLG ACTUATOR ATTACH POINT. METHOD OF INSPECTION WAS DYE PENETRANT. THIS CRACK WAS FOUND TO BE BEYOND LIMIT ALLOWABLE OF MEB91-11R1. THIS UNIT HAS BEEN SCRAPPED & A REPLACEMENT DRAG BRACE HAS BEEN INSTALLED IN ACFT.
THE NR 3 CYLINDER OF THE RIGHT ENGINE HAD A CRACKED HOLD DOWN NUT.
AT SCHEDULED INSPECTION, NLG DRAG BRAC OEM PN 5142002-5 WAS FOUND TO BE CRACKED IN THE AREA OF NLG ACTUATOR ATTACH POINT. METHOD OF INSPECTION WAS DYE PENETRANT. THIS CRACK WAS FOUND TO BE WITHIN ALLOWABLE LIMIT. THIS UNIT HAS BEEN REPAIRED IAW PROCEDURE OUTLINED IN MEB941-11R1 & RETURNED TO SERVICE.
CREW REPORTED, WHILE PERFORMING "IN RANGE" CHECKLIST, RT ENGINE QUIT. CREW PERFORMED ENGINE FAILURE CHECKLIST, AND WHEN AUXILARY FUEL PUMP WAS TURNED ON HIGH POSITION, ENGINE POWER WAS RESTORED. EMERGENCY WAS DECLARED, AND CREW ELECTED TO DIVERT BECAUSE OF BETTER WEATHER CONDITONS. LANDING WAS UNEVENTFUL, BUT AFTER LANDING, RT ENGINE QUIT AGAIN. MX INSPECTED RT ENGINE, PERFORMED GROUND RUN OF ENGINE, FOUND HIGH FUEL FLOW AND IDLE MIXTURE SETTINGS OUT OF LIMITS. AJUSTED BOTH HIGH FUEL FLOW AND IDLE MIXTURE SETTINGS, GROUND RUN CHECKED OK. AS A PRECAUTIONARY MEASURE, LT AND RT FUEL SYS WERE SERVICED WITH ISOPROPYL ALCOHOL IAW MM. AFT RELEASED BACK TO SERVICE.
CREW REPORTED HSI FAILED (FROZEN) DURING CLIMB IN HEAVY RAIN AND MODERATE TURBULENCE. EMERGENCY DECLARED, DIVERTED. LANDING WAS UNEVENTFUL. MX FOUND REMOTE GRYO CIRCUIT BREAKER POPPED. R & R REMOTE GYRO. ACFT RELEASED BACK TO SERVICE.
WHILE EN ROUTE, THE RT HYD FLOW LIGHT BEGAN TO FLICKER, FOLLOWED SHORTLY THEREAFTER BY THE LT HYD FLOW LIGHT. COMPLETED HYD FLOW "LIGHT ILLUMINATED IN FLIGHT" CHECKLIST. ON DESCENT, LOWERED LANDING GEAR; GREEN NOSE WHEEL GEAR INDICATION LIGHT DID NOT ILLUMINATE. COMPLETED "GEAR WILL NOT EXTEND HYDRAULICALLY" CHECKLIST; THE GREEN NOSE WHEEL DOWN AND LOCKED LIGHT STILL DID NOT ILLUMINATE. DECLARED AN EMERGENCY WITH CAPE APPROACH AND DIVERTED. COMPLETED "LANDING WITH A DEFECTIVE NOSE GEAR CHECKLIST" AND LANDED RUNWAY 24. NOSE GEAR COLLAPSED ON LANDING. MX FOUND HYD SYS FLUID DEPLETED.
CREW REPORTED AVIONIC MASTER SWITCH INOPERATIVE. MX REMOVED AND REPLACED SWITCH, AND RETURNED ACFT TO SERVICE.
WARPED VALUE. (K)