N77SF
Registered owner: SENECA FOODS CORP, NY (owner ≠ operator)
Operators of this aircraft
Who operated this tail, and how firmly we know it.
| Operator | Role | Period | Basis |
|---|---|---|---|
| SENECA FLIGHT OPERATIONS (SFOA) | Certificate holder | — | Matched by certificate designator |
Accident & incident history
No NTSB accidents or incidents on file for this aircraft.
Maintenance disclosures
DURING LANDING, THE LT ENGINE OIL PRESSURE ANNUNCIATOR ILLUMINATED AND CREW NOTED THE OIL PRESSURE WAS AT 23PSI, THE ENGINE WAS SHUT DOWN AND THE AIRCRAFT WAS GROUNDED AND TURNED OVER TO MAINTENANCE FOR TROUBLESHOOTING. CREW ALSO NOTED THE OIL FILTER BYPASS INDICATOR WAS EXTENDED AFTER A POST SHUTDOWN CHECK. THE LT ENGINE OIL FILTER AND AN OIL SAMPLE WERE SENT FOR SPECTROGRAPHIC OIL ANALYSIS, THIS ENGINE HAD 8.3HRS SINCE THE PREVIOUS SOAP SAMPLE AND WAS ON A 25HR RE-SAMPLE FOR CONTAMINATION. RESULTS OF ANALYSIS INDICATED A FAULTY OIL PUMP. AN OVERHAULED PUMP WAS ACQUIRED AND INSTALLED AND THE AIRCRAFT WAS RETURNED TO SERVICE. A RE-SAMPLE OF THE OIL & FILTER IS TO BE PERFORMED IN 25HRS PER ENGINEERING.
AFTER LANDING AT DESTINATION AIRPORT AND AFTER SUBSEQUENT ENGINE SHUT DOWN THE CREW COULD NOT OPEN THE CABIN DOOR. INITIALLY ICE WAS SUSPECTED AS THE CAUSE BUT AFTER THAWING THE DOOR STILL COULD NOT BE OPENED. MAINTENANCE WAS CALLED AND IT WAS DETERMINED THAT AT LEAST ONE DOOR PIN WAS NOT RETRACTING FROM THE DOOR FRAME. CREW AND PASSENGERS DEPARTED FROM THE EMERGENCY EXIT. A SPECIAL FLIGHT PERMIT WAS ACQUIRED AND THE AIRCRAFT WAS FLOWN BACK TO HOME BASE (PEO) WHERE AN UNEVENTFUL LANDING WAS MADE. ON INITIAL INSPECTION IT WAS FOUND THAT ALL DOOR PINS ON THE AFT SIDE WOULD NOT FULLY RETRACT. THE DOOR STEPS, & TRIM WERE REMOVED AND EVENTUALLY THE CAUSE WAS FOUND TO BE DEBRIS AT THE SECOND FROM THE BOTTOM AFT DOOR PIN, WHICH WAS JAMMED BETWEEN RECEPTACLE BLOCK AND THE HOLE IN THE FRAME WHICH ALLOWS THE PIN TO FULLY RETRACT. THE DEBRIS, AFTER RETRIEVAL FROM DOOR FRAME WAS FOUND TO BE AN AN960-4L WASHER. THE WASHER WAS BEND/FOLDED OVER BUT IT CANNOT BE DETERMINED IF THE BEND WAS FROM THE JAMMING IN THE RECEPTACLE OR NOT. IT IS BELIEVED THE WASHER HAD BEEN THERE FOR SOME TIME, EITHER FROM PREVIOUS MAINTENANCE OR FROM THE FACTORY, AND EVENTUALLY FOUND ITS WAY TO THE AREA THAT ALLOWED IT TO JAM THE DOOR PIN. THE ENTIRE DOOR, DOOR STRUCTURE, LATCHING SYSTEM & ALL ATTACHMENT HARDWARE WERE INSPECTED. ALL LOOKED OK AND NO FURTHER DEBRIS COULD BE FOUND ANYWHERE IN THE DOOR STRUCTURE OR AROUND THE LATCHING MECHANISMS.THE AIRCRAFT WAS RETURNED TO SERVICE.
UPON ENGINE START THE RT ITT INDICATOR SHOWED NO INDICATION ON THE TAPE OR DIGITAL INDICATORS. NO ENGINE COMPUTER FAULTS WERE INDICATED. MEL ALLOWS FOR THE TAPE OR THE DIGITAL TO BE INOPERATIVE BUT NOT BOTH. A SPECIAL FLIGHT PERMIT WAS ACQUIRED AND THE ACFT WAS FLOWN BACK TO HOME BASE WITHOUT INCIDENT. A REPLACEMENT INDICATOR WAS ACQUIRED AND INSTALLED WHICH CORRECTED THE PROBLEM. IT IS BELIEVED THAT A DEFECT WAS CREATED DURING THE O/H PROCESS WHICH CAUSED THIS ISSUE.
UPON DECENT FROM CRUISE A SHUDDER WAS DETECTED WHEN THE POWER LEVERS WERE RETARDED. FLIGHT CREW WAS ABLE TO DETERMINE IT WAS THE RT ENG CAUSING THE SHUDDER. ALL ENG PARAMETERS WERE NORMAL, AS SAFE LANDING WAS MADE. INVESTIGATION RESULTED IN THE DISCOVERY OF THE AFT ACCESSORY GEAR BOX BOLTS MISSING NUTS & WASHERS & THE INBD BOLT HAD SLID ALMOST ALL THE WAY OUT. NEW NUTS & WASHERS WERE INSTALLED & PROPERLY TORQUED. A SATISFACTORY FLIGHT TEST WAS THEN COMPLETED. THE ENG HAD RECENTLY BEEN DISASSEMBLED FOR A LIGHTNING INSPECTION BY THE MFG, IT IS BELIEVED THAT THE INSTALLATION OF THESE TWO NUTS WERE NEGLECTED AT THAT TIME.
UPON TAKE OFF THE LT RUDDER PEDAL DEFLECTED FULL LT. THE RUDDER BIAS SYS WAS DEACTIVATED & THE RUDDER SYS RETURNED TO NORMAL. AFTER LANDING THE RUDDER BIAS SYS WAS TESTED & CHECKED OK, BUT RUDDER PEDAL WOULD STILL DEFLECT WHEN ENG POWER WAS APPLIED. IT WAS DETERMINED THAT MOISTURE DUE TO CONDENSATION HAD ENTERED THE VERTICAL LINE GOING TO THE BIAS CYLINDER WHICH IS NOT HEATED & FROZE EITHER DURING FLIGHT OR AFTER LANDING BLOCKING PRESS TO ONE SIDE OF THE BIAS SYS. THE WATER WAS EXTRACTED & SYSTEM OPERATES NORMALLY. PRIOR TO FLIGHT IN FREEZING TEMPS THAT THE SYS BE FLUSHED BY THE FLIGHT CREW ON FIRST FLIGHT OF THE DAY BY OPERATING ONLY ONE ENG TO POWER FOR SEVERAL SECONDS WITH THE RUDDER BIAS SYS OFF.
UPON ENG START UP FOR DEPARTURE, PILOT NOTED LT DIGITAL TURBINE INDICATOR SHOWED NO DIGITS. ENG STARTED NORMALLY & ALL OTHER INSTRUMENTS READ NORMAL & THERE WERE NO ENG COMPUTER FAULTS. A SPECIAL FLIGHT PERMIT WAS ISSUED & ACFT WAS FLOWN TO HOME BASE WHERE IT WAS DETERMINED THAT THE INDICATOR WAS FAULTY. AN OVERHAULED INDICATOR WAS INSTALLED & THE ACFT RETURNED TO SERVICE. THE FAILED INDICATOR HAD 1.1 HRS SINCE OVERHAUL & A RECORDS CHECK SHOWED IT HAD BEEN REPAIRED FOR THE SAME DISCREPANCY.
APPROXIMATELY AFTER 1 HOUR INTO FLIGHT THE RT WINDSHIELD CRACKED. FLIGHT MANUAL PROCEDURES FOR THIS TYPE OF OCCURRENCE WERE FOLLOWED & AN UNEVENTFUL LANDING WAS MADE. AFTER LANDING INSPECTED THE WINDSHIELD & DETERMINED THE CRACKING HAD OCCURRED IN THE OUTER PANE ONLY. THE WINDSHIELD WAS SUBSEQUENTLY REPLACED WITH A FACTORY NEW WINDSHIELD & THE ACFT WAS RETURNED BACK TO SERVICE. THE CAUSE OF THE CRACKING IS TO BE DETERMINED BY THE INSURANCE COMPANY AS IT IS SUSPECTED A POSSIBLE EARLIER LIGHTNING STRIKE MAY HAVE BEEN A DETERMINING FACTOR IN THE FAILURE. IF LIGHTENING WAS NOT A FACTOR IT IS BELIEVED CRACKING MAY HAVE BEEN DUE TO A FAILURE OF THE HEATING ELEMENT AT THE LOWER BUSS BAR.
DURING CRUISE FLIGHT THE NR 1 ITT INDICATOR WENT TO ZERO. THE AIRCRAFT RETURNED TO HOME BASE WHERE AN UNEVENTFUL LANDING WAS MADE, DURING RETURN FLIGHT THE INDICATOR BEGAN TO WORK BUT WAS LOWER THAN NORMAL AND ERRATIC. THE GAUGE WAS PARTIALLY REMOVED FROM THE PANEL AND THE PROBLEM COULD BE DUPLICATED BY TAPPING ON THE BACK OF THE GAUGE. THE GAUGE WAS REPLACED WITH AN OVERHAULED UNIT AND GROUND OPERATIONS CHECKS WERE NORMAL. THE AIRCRAFT WAS RETURNED TO SERVICE.
AFTER REACHING THIS ALTITUDE THE PILOTâS WINDOW CRACKED IN NUMEROUS PLACES. FOLLOWING FLIGHT MANUAL PROCEDURES, THE CREW SLOWED THE AIRCRAFT TO 230K AND DESCENDED TO AN ALTITUDE WHERE A CABIN DIFFERENTIAL PRESSURE OF 7.5 COULD BE MAINTAINED. THE CREW THEN DECIDED TO DIVERT TO NEAREST AIRPORT WHERE AN UNEVENTFUL LANDING WAS MADE. THERE WAS NO LOSS OF PRESSURIZATION, NO INDICATION OF ANY IMPACT, THE AIRCRAFT APPEARED TO BE OPERATING NORMALLY, AND THE WINDSHIELD HEAT WAS ON. IT WAS DECIDED TO REPLACE THE WINDSHIELD WHERE IT LANDED. THE WINDSHIELD WAS LAST REPLACED IN 1995 AND A SERVICEABLE WINDSHIELD WAS INSTALLED AT THAT TIME. IT IS BELIEVED THAT THE CAUSE OF THE CRACKS WERE DUE TO EROSION OF THE OUTER SURFACE ANTI-STATIC COATING, AND A STATIC BUILD UP ON THE OUTER SURFACE OF THE WINDOW WHICH FOUND A GROUND PATH THROUGH THE WINDOW VIA THE WINDSHIELD HEATING ELEMENTS.
JUST PRIOR TO DESCENT TO SCHEDULED AIRPORT, THE LT ENGINE COMPUTER ANNUNCIATOR ILLUMINATED. FOLLOWING AFM PROCEDURES THE COMPUTER WAS RESET AND THE LIGHT WOULD NOT REMAIN EXTINGUISHED. ALL OTHER ENGINE INDICATIONS WERE NORMAL. A SAFE LANDING WAS MADE. THE PILOT WAS DIRECTED TO RETRIEVE FAULT CODES MANUALLY FROM THE ENGINE COMPUTER WHICH REVEALED A FAULT IN THE FUEL CONTROL UNIT (FCU) POWER LEVER ANGLE TRANSMITTER. MAINTENANCE WAS ARRANGED FROM A NEARBY AIRPORT TO ARRIVE THE FOLLOWING DAY TO LOOK INTO THE ISSUE. AFTER ANALYZING THE NR 1 DIGITAL ELECTRONIC ENGINE COMPUTER (DEEC) LIVE DATA, IT COULD NOT BE DETERMINED THAT THERE WERE ANY FAULTS. NO FAULT CODES WERE RECORDED BY REQUESTING FLT ON THE HTT INTERFACE, BUT THE MEMORY WAS FULL AND REQUIRED DOWNLOAD. THE ENGINE WAS STARTED AND RAN FOR A LENGTH OF TIME WITH THE COMPUTER BEING MONITORED AND NO FAULTS WERE SHOWN AND THE INITIAL FAULT COULD NOT BE DUPLICATED. AN INSPECTION WAS MADE OF THE WIRE HARNESS AND NO DEFECTS WERE FOUND. THE AIRCRAFT WAS RETURNED TO SERVICE AND THE DOWNLOADED DATA SENT TO JET CARE TO BE ANALYZED. AFTER THE AIRCRAFT ARRIVED BACK AT HOME BASE, THE DOWNLOAD FROM THE DEEC WAS RECEIVED AND VIEWED BY THE DIRECTOR OF MAINTENANCE. AFTER A REVIEW OF THE DOWNLOAD IT WAS DISCOVERED THAT THE WERE STORED IN THE FAULT HISTORY. A CURRENT DOWNLOAD OF THE DEEC WAS MADE AND SHOWED NO FAULTS ON THE TRIP TO HOME BASE. THE AIRCRAFT WAS SCHEDULED AND FLOWN TO A MAINTENANCE FACILITY, WITHOUT INCIDENT, FOR FURTHER REVIEW. A MORE DETAILED INSPECTION OF THE HARNESS REVEALED NO FAULTS AND IT WAS DECIDED TO REPLACE THE FUEL CONTROL UNIT AS IT IS THE MOST LIKELY UNIT TO CAUSE THIS TYPE OF FAILURE. THE AIRCRAFT HAS BEEN RETURNED TO SERVICE. TO DATE WE HAVE NO EXPLANATION AS TO WHY THIS FAULT OCCURRED OR WHY IT COULD NOT BE VIEWED ON THE DEEC HTT LIVE DATA. IN THE FUTURE, THE DOWNLOADED DATA WILL BE REVIEWED PRIOR TO RETURNING THE AIRCRAFT TO SERVICE.
AFTER DEPARTURE FROM AIRPORT THE RT ENGINE COMPUTER ANNUNCIATOR ILLUMINATED. FOLLOWING AFM PROCEDURES THE COMPUTER WAS RESET AND THE LIGHT EXTINGUISHED. A SHORT TIME LATER THE ANNUNCIATOR ILLUMINATED AGAIN AND WAS AGAIN RESET. ALL OTHER ENGINE INDICATIONS WERE NORMAL. IT WAS DECIDED TO DIVERT AIRPORT WHERE MAINTENANCE FACILITY WAS AVAILABLE AND HAVE THE ANNUNCIATION INVESTIGATED. ON THE FLIGHT TO THE AIRPORT THE ANNUNCIATOR REMAINED EXTINGUISHED. AFTER ANALYZING FAULT CODES OF NR 2 DIGITAL ELECTRONIC ENGINE COMPUTER (DEEC), IT WAS DISCOVERED THERE WAS A FAULT IN THE N2 MONOPOLE (SPEED SENSOR). THE N2 MONOPOLE ON THE NR 2 ENGINE WAS REPLACED, AN ENGINE RUN PERFORMED, AND THE AIRCRAFT RETURNED TO SERVICE. DATA FROM THE DOWNLOAD OF THE DEEC SHOWED NO OTHER FAULTS. WHILE THIS FAILURE IS SOMEWHAT RARE, IT IS ALSO NOT UNCOMMON AND USUALLY FAILS ON THE COMPUTER CIRCUIT SIDE OF THE MONOPOLE WHICH ALLOWS FOR PILOT TO HAVE NORMAL INDICATION OF ENGINE SPEED ON THE N2 INDICATOR IN THE COCKPIT WHICH ALLOWS PILOT TO VERIFY PROPER ENGINE FUNCTION. NO INFORMATION ON THE CAUSE OF THESE FAILURES BUT WOULD SUSPECT FATIGUE FROM VIBRATION AS THIS SENSOR IS MOUNTED ON THE ACCESSORY GEARBOX.
AFTER LANDING, THE NR 2 HYDRAULIC LIGHT CAME ON AND THE NR 2 HYDRAULIC PRESSURE WENT TO -0- PSI. INVESTIGATION REVEALED THE NR 2 HYDRAULIC PUMP HAD FAILED. THE PUMP AND REQUIRED FILTERS WERE REPLACED AND THE AIRCRAFT WAS RETURNED TO SERVICE. THIS FAILED, OVERHAULED PUMP WAS A RECENT WARRANTY REPLACEMENT FOR PREVIOUS OVERHAULED PUMP THAT HAD FAILED WITH LOW (220 HRS) TSO. BOTH PUMPS WERE O/H BY SAME REPAIR STATION. THIS OPERATOR HAS NEVER SEEN THIS BRAND OF PUMP GO TO THE REQUIRED O/H INTERVAL (3,000 HRS). THESE PUMPS GENERALLY SEEM TO FAIL AROUND 700-900 HRS OFOPERATING TIME AS DERIVED FROM PREVIOUS AC RECORDS. (K)
AFTER TAKEOFF AND DURING CLIMBOUT, THE PILOT EXPERIENCED A COMPUTER GENERATED AUTOMATIC ROLL BACK OF POWER ON THE NR 1 ENGINE. THE NR 2 ENGINE WAS BROUGHT BACK TO A MATCHING POWER SETTING. IT WAS THEN NOTICED THAT THE NR 1 ENGINE ITT WAS MORE THAN 100 DEGREES HIGHER THAN THE NR 2 ENGINE. THE NR 1 ENGINE WAS SHUT DOWN AS A PRECAUTIONARY MEASURE, AND AN UNEVENTFUL LANDING WAS MADE. AFTER SEVERAL GROUND MAINTENANCE RUNS FOR TROUBLESHOOTING, IT WAS DETERMINED THAT SEVERE HOT SECTION DISTRESS HAD OCCURRED. THE ENGINE WAS REMOVED FOR REPAIR. CAUSE OF PROBLEM UNKNOWN.
PILOT REPORTED THE WING DEICE SYSTEM WAS INOPERATIVE. AFTER VERIFYING ELEC PORTION OF SYS WAS FUNCTIONING, A GROUND OPER CHK PERFORMED. DISCOVERED VERY LITTLE FLOW GETTING TO RT SLATS, LT SLATS APPEARED TO BE GETTING SUFFICIENT HEAT, BUT BOTH SIDES ARE REQUIRED TO OPER PROPERLY TO GET A PROPER INDICATION ON PANEL. AFTER VERIFYING NO LEAKS IN AIRFRAME DUCTING, DISCOVERED THE INTERIOR WALLS OF FLEX DUCTS ATTACHED TO SLATS WERE DEBONDED AND COLLAPSING. THIS EITHER RESTRICTED/BLOCKED FLOW OF HOT AIR TO SLATS. INSP OF LT FLEX DUCTS REVEALED SAME CONDITION EXISTED, FAILURE OF THAT SIDE WAS IMMINENT. DUCTS HAVE A 3,000 HR TBO AND WERE JUST REPLACED 66.6 HRS PRIOR. SUSPECT INCORRECT MFG PROCESS. (X)
THE PILOT REPORTED THERE WAS AN ABNORMAL 'THUMP' NOISE COMING FROM THE NOSE GEAR AREA WHEN THE GEAR WAS RETRACTED ON SEVERAL OCCASIONS. AN INVESTIGATION REVEALED THE CENTER RT NOSE LANDING GEAR DOOR BELLCRANK/HINGE WAS BROKEN IN HALF. AN INSPECTION OF THE ENTIRE NOSE GEAR AND WHEELWELL AREA SHOWED NO FURTHER DAMAGE. METAL FATIGUE IS THE SUSPECTED CAUSE OF THIS FAILURE. SUBMITTER SUGGESTED CLOSE INSPECTION OF THESE HINGES BE MADE ANY TIME LANDING GEAR WORK IS PERFORMED AS WELL AS DURING ALL PRE AND POST-FLIGHT INSPECTIONS.
DURING START OF THE RIGHT (NR 2) ENGINE, THE CREW NOTICED AN UNUSUAL NOISE THAT LASTED APPROXIMATELY 30 SECONDS. SCANNING THE INSTRUMENTATION REVEALED THE 'HYD 2' LIGHT ILLUMINATED AND THE HYDRAULIC PRESSURE GAUGE INDICATED ZERO. EXAMINATION OF THE RT ENGINE DRIVEN HYDRAULIC PUMP AFTER REMOVAL REVEALED THE DRIVESHAFT WAS INTACT, HOWEVER, IT ROTATED WITH LITTLE RESISTANCE INDICATING AN INTERNAL FAILURE. PUMP TBO IS 3,000 HOURS, HOWEVER, THIS INTERVAL IS RARELY ACHIEVED.
AFTER A NORMAL FLIGHT, HYDRAULIC FLUID WAS NOTICED RUNNING DOWN THE VERTICAL STABILIZER EMANATING FROM THE AFT ELEVATOR AREA. INVESTIGATION REVEALED THAT ONE OF THE FLEX HYDRAULIC HOSES FOR THE RUDDER/YAW SERVO WAS MAKING CONTACT WITH AND RUBBED THROUGH THE RIGID HYDRAULIC LINE (FOR THE SERVO) CAUSING THE LEAK. NO DAMAGE WAS EVIDENT TO THE FLEX HOSE. REPLACED THE LINE WITH A NEW ASSEMBLY. THIS AREA IS NOT READILY ACCESSIBLE AND THE DAMAGE WAS DIFFICULT TO LOCATE EVEN WITH A MIRROR. CLOSE INSPECTION OF THIS AREA SHOULD BE ACCOMPLISHED ANYTIME ACCESS IS GAINED TO THE RUDDER SERVO, AT WHICH TIME THE HOSE/LINE CLEARANCE SHOULD BE CHECKED THROUGH FULL RANGE OF RUDDER TRAVEL.