WARBELOWS AIR VENTURES INC

Operated by Warbelows Air Ventures Inc (per NTSB report)

Operated by Warbelows Air Ventures (per NTSB report)

Operated by WARBELOWS AIR VENTURES INC (per NTSB report)

Operated by WARBELOWS AIR VENTURES INC (per NTSB report)

LEFT AND RIGHT VOLTAGE REGULATOR AND GROUND VENT FAN CIRCUIT BREAKERS ALL TRIPPED SIMULTANEOUSLY DURING FLIGHT AND WOULD NOT RESET. AIRCRAFT RETURNED TO FAI WITHOUT INCIDENT. MAINTENANCE FOUND SMALL BUSS BAR IN THE CIRCUIT BREAKER PANEL HAD A LOOSE CONNECTION. ATTACHMENT HARDWARE WAS REPLACED AND BUSS BAR WAS SECURED WITH GOOD RESULT. AIRCRAFT WAS RETURNED TO SERVICE.

UPON LANDING, NOSE GEAR COLLAPSED ------ PILOT REPORTS ON APPROACH HE HAD THREE GREEN LIGHTS INDICATING GEAR WAS DOWN AND LOCKED AND NO EVIDENCE OF ANY ISSUES. ONCE THE NOSE GEAR CAME IN CONTACT WITH THE RUNWAY THE PILOT HEARD A LOUD NOISE FROM THE NOSE GEAR AREA AND THE GEAR COLLAPSED.

PILOT WAS IN CRUISE FLIGHT AND EXPERIENCED A PARTIAL POWER LOSS AND THEN OIL PRESSURE LOSS OF THE RIGHT ENGINE. PILOT SHUT DOWN ENGINE AND LANDED WITHOUT FURTHER INCIDENT. UPON INSPECTION OF ENGINE IT WAS FOUND THAT THE SHAFT WAS BROKEN AND BOTHER TURBINE AND COMPRESSOR BLADES WERE DAMAGED. TURBO WAS A RECENT INSTALL AFTER OVERHAUL BY ATC AND HAD 87.9 HOURS TSO. MECHANICS VERIFIED THAT THE TURBO WAS PRE-OILED PRIOR TO RETURN TO SERVICE AND NO ISSUES WERE REPORTED POST-INSTALL.

PILOT REPORTED, "RT OUTBOARD FUEL GAUGE READS FULL CLOCKWISE - ALL THE TIME." FUEL QUANTITY SYSTEM WAS DEFERRED PER MEL 28-4 "FUEL QUANTITY INDICATORS" ON DMR #5111 CATEGORY "C" WITH A DURATION OF 10 DAYS. THE AIRCRAFT WAS BROUGHT IN FOR MAINTENANCE ON 27 DECEMBER 2018 AFTER FLYING 2.5 HOURS SINCE DEFERRAL. DURING TROUBLESHOOTING THE RIGHT INBOARD AUX FUEL SENDER WAS FOUND TO BE DEFECTIVE AND SHOWED AN INDICATION THAT ABNORMALLY HIGH HEAT HAD BEEN GENERATED DURING THE TIME OF THE SENDER'S FAILURE. THERE WAS EVIDENCE OF HEAT DISCOLORATION AND POSSIBLE SMOKE STAINS ON THE SENDER'S WIPER CASE AND SUPPORT BRACKET. DISASSEMBLY OF THE WIPER CASE REVEALED THAT THE WIPER WAS DEFORMED DUE TO HIGH HEAT AND THE POTENTIOMETER STRIP WAS DAMAGED BY WHAT APPEARS TO BE ELECTRICAL ARCING. THERE WAS EVIDENCE OF MELTED PLASTIC AND SMOKE RESIDUE INSIDE AND OUTSIDE THE WIPER CASE. THERE WAS NO DAMAGE INFLICTED IN THE FUEL CELL OR THE WIRING TO/FROM THE FUEL QUANTITY SENDER.

EXHAUST VALVE GUIDE LEAKING OIL. LOSS OF COMPRESSION. FOUND POOLING OF EXCESS OIL IN ROCKER BOX CAVITY AND SIGNS OF EXHAUST BLOW-BY ON EXHAUST VALVE SPRINGS. THIS IS THE 4TH VALVE GUIDE TO EXIBIT EXCESSIVE WEAR PROBLEM. THE CYLINDER WAS INSTALLED AS FACTORY NEW.

ON APPROACH, NOTICED THAT ONLY THE TWO MAIN GEAR INDICATOR LIGHTS INDICATED GREEN. THE NOSE GEAR INDICATOR LIGHT WAS NOT ILLUMINATED AND THE RED TRANSFER LIGHT WAS ILLUMINATED. T RECYCLED THE GEAR HANDLE, NO CHANGE TO THE MAIN OR THE NOSE GEAR POSITIONS. THE APPROACH WAS ABORTED AND THE AIRCRAFT WAS FLOWN BACK DEPARTURE, WITH THE GEAR EXTENDED. AS THE AIRCRAFT APPROACHED, INSTRUCTED TO CYCLE THE LANDING GEAR EMERGENCY PUMP. THERE WAS NO CHANGE IN THE NOSE GEAR POSITION. THE DECISION WAS MADE TO LAND THE AIRCRAFT WITH THE NOSE GEAR IN NOT DOWN AND NOT LOCKED POSITION. SET THE AIRCRAFT DOWN. AFTER LANDING, IT WAS DETERMINED THAT THE NOSE GEAR ACTUATOR'S DOWN PRESSURE FITTING HAD SHEARED AT THE ATTACHMENT SITE OF THE ACTUATOR.

DURING FLIGHT AJ100, APPROXIMATELY 10 MILES FROM DESTINATION, THE LEFT ENGINE SHUTTERED BRIEFLY AND ENGINE OIL WAS OBSERVED STREAMING FROM THE COWLING. THE PILOT FEATHERED THE LEFT PROPELLER AND IMMEDIATELY SHUTDOWN THE ENGINE. THE FLIGHT CONTINUED AND THE AIRCRAFT LANDED WITHOUT INCIDENT. MAINTENANCE PERSONNEL DISCOVERED THAT THE NR 6 CYLINDER HAD SEPARATED FROM THE ENGINE, THE CAM SHAFT HAD SHATTERED INTO SEVERAL PIECES, A GROOVE WAS GOUGED BY THE CYLINDER'S PISTON CONNECTING ROD INTO THE CASE HALF NR 6 CYLINDER OPENING, AND A LARGE PORTION OF THE CASE HALF HAD BEEN BROKEN OUT AROUND THE SHEARED CYLINDER'S ATTACH BOLTS. THIS ENGINE WILL BE SENT TO THE MANUFACTURER FOR A TEAR-DOWN ANALYSIS AND WE WILL ATTACH, THEIR FINDINGS TO THIS REPORT AS RECEIVED.

AFTER SUCCESSFUL LANDING, PILOT REPORTED THAT THE LANDING GEAR WOULD NOT EXTEND AND HE HAD TO MANUALLY PUMP DOWN THE GEAR. MAINTENANCE EXAMINATION REVEALED THAT THE RT HYDRAULIC FILTER BOWL HAD RUPTURED IN THE THREADED PORTION APPROXIMATELY 0.25" ABOVE THE O-RING FLANGE. THE RUPTURE WAS NEARLY 75 PERCENT AROUND THE CIRCUMFERENCE OF THE THREADS. MAINTENANCE HAS PROPOSED, FOR OUR OPERATION, THAT WE REPLACE THESE HYDRAULIC BOWLS AROUND 4,000 HOURS TIME IN SERVICE, DUE TO THE NUMBER OF TIMES THAT WE REMOVE AND REINSTALL DURING SCHEDULED INSPECTIONS.

RT. ENGINE, OIL TEMP REDLINE (HIGH), OIL PRESSURE LOW (REDLINE). ATTEMPTED TO SLOW ACFT AND UNCONGEAL OIL COOLER. THIS DID NOT HELP. PERFORMED PRECAUTIONARY SHUTDOWN. ON LANDING, MX INSPECTED FOR POSSIBLE OIL COOLER CONGEALING, DUE TO THE EXTREME OAT (-21°F). ENGINE OIL LEVEL WAS CHECKED AND WAS FOUND TO BE IN ACCEPTABLE RANGE. THE OIL FILTER WAS OPENED AND INSPECTED FOR CONTAMINATION, AND THE OIL STRAINER WAS INSPECTED - BOTH WITH NO DISCREPANCIES FOUND. AS A PRECAUTIONARY MEASURE, THE ENGINE VERNATHERM, VALVE ASSY TEMP CONTROL, OIL COOLER BYPASS, WAS REPLACED WITH NEW. AN ENGINE RUNUP FOR LEAK/OPS CHECK WAS PERFORMED WITH NO DISCREPANCIES FOUND.

DURING THE PERIODIC INSPECTION, A 0.125 INCH CRACK WAS DISCOVERED DURING DYE PENTRANT IN LOWER INBD FLANGE RADIUS OF THE LT TRUNNION ASSY -LANDING GEAR AFT.

DURING PERIODIC INSPECTION, A 0.125" CRACK WAS DISCOVERED BY DYE PENETRANT IN THE LOWER INBD FLANGE RADIUS OF THE LT TRUNNION ASSY, LANDING GEAR AFT.

PILOT REPORTED VENT FAN FAILED IN FLIGHT. SMELLED SMOKE DURING CLIMB AFTER DEPARTURE. PILOT RETURNED TO DEPARTURE. BOTH VENT FANS WERE REMOVED, NEITHER SHOWING EVIDENCE OF MALFUNCTION. BOTH WERE OPERATED ON BATTERY POWER WHILE REMOVED FROM ACFT WITHOUT ANY SIGN OF OVERHEATING OR SMOKE. BOTH VENT FANS WERE REPLACED AS A PRECAUTION. NO SIGNS OF SMOKE’S SOURCE WAS FOUND AFTER DETAILED INVESTIGATION OF WIRING AND COMPONENTS BEHIND INSTRUMENT PANEL. CHECKED THE AVIONICS COOLING FAN AND FLAP MOTOR FOR OVERHEATING AND AS POSSIBLE SMOKE SOURCES, NOTHING ABNORMAL FOUND. AFTER COMPLETION OF AAIP EVENT NR 3, ACFT WILL BE SENT ON CHECK FLIGHT TO ENSURE INTEGRITY OF VENT FANS AND ELECTRICAL WIRING.

ENROUTE, PILOT BEGAN TO DETECT SMOKE. RETURNED TO DEPARTURE. DURING RETURN, PILOT SHUTDOWN ELECTRICAL SYS & LANDED WITHOUT INCIDENT. AFTER ELECTRICAL SYS WAS SHUTDOWN, PILOT NOTICED A DECREASE IN THE ODOR OF SMOKE. MX DISCOVERED THE LEFT INTERIOR VENT FAN HAD SEIZED BEARINGS. SEIZED BEARINGS CAUSED THE MOTOR'S WINDINGS TO HEAT UP. MX FOUND NO EXTERNAL CHARRING OR DISCOLORATION TO THE MOTOR OR ANY ADJACENT EQUIPMENT OR STRUCTURE. NO SMOKE DAMAGE TO THE INTERIOR OF ACFT, AND THERE WAS NO EXTERNAL WIRING DAMAGE. VENT FAN ASSY WAS REPLACED AND ACFT RETURNED TO SERVICE.

CRACKS IN AFT MAIN GEAR SIDE BRACE FITTING ASSEMBLY P/N 40294-00. WE INITIATED A DYE PENETRANT INSPECTION PROGRAM ON THE FORWARD AND AFT MAIN GEAR SIDE BRACE FITTING ASSEMBLIES OF OUR PIPER CHIEFTAIN NAVAJO FLEET. THE INITIAL INSPECTION OF OUR AIRCRAFT REVEALED THAT SEVERAL OF THE AFT FITTING ASSEMBLIES ON BOTH THE LEFT AND RIGHT LANDING GEAR HAVE CRACKS LOCATED IN THE LOWER INBOARD WEB OF THE SIDE BRACE (PIPER PART NUMBER 40294-00). AS A RESULT OF FINDING THESE CRACKS, WE HAVE ADDED A 1,000 HOUR SPECIAL INSPECTION TO OUR PA31-350 AAIP, SO THAT WE MAY MONITOR AND REPLACE ANY ASSEMBLIES WHICH EXHIBIT THE CRACKING FOUND IN THE FITTING ASSEMBLIES. IT IS INTERESTING TO NOTE THAT THE CRACKS HAVE ONLY BEEN FOUND IN THE AFT ASSEMBLIES ON OUR AIRCRAFT.

DYE PENETRENT INSPECTION REVEALED SMALL CRACK BEGINNING TO FORM ON TRUNNION JUST BELOW THE BUSHING AREA ALONG A CASTING RIDGE. THIS WAS THE RIGHT AFT MLG TRUNNION. IDENTICAL PART IS USED ON BOTH AFT TRUNNION, LEFT SIDE NOT CRACKED. FWD TRUNNIONS (DIFFERENT PART NUMBER) NOT FOUND TO BE CRACKED AT THIS TIME. ALTHOUGH TOTAL PART TIME IS NOT KNOWN, IT IS ASSUMED THAT THESE ARE ORIGINAL EQUIPMENT, WE HAVE NEVER REPLACED THESE BEFORE ON ANY OF OUR FLEET OF 8 OTHER NAVAJO CHIEFTANS.

COMPLETE ELECTRICAL SYSTEM FAILURE. PILOT REPORTED: AFTER TAKEOFF AT CXF LT ALTERNATOR LIGHT CAME ON, 15 MINUTES LATER RT ALTERNATOR LIGHT CAME ON. INSPECTION REVEALED A DEAD BATTERY, A BROKEN FIELD WIRE ON THE LEFT ALTERNATOR AND A RIGHT ALTERNATOR BELT IN NEED OF REPLACEMENT. LEFT ALTERNATOR FIELD WIRE WAS REPAIRED, RIGHT ALTERNATOR BELT WAS REPLACED, BATTERY WAS SERVICED. ALL OPERATION CHECKS SATISFACTORY.

PILOT WAS ON APPROACH AND NOTICED GEAR UNSAFE LIGHT FAILED TO EXTINGUISH ON GEAR DOWN SELECTION. GREEN LIGHT ALSO FAILED TO ILLUMINATE FOR NOSE LANDING GEAR. PILOT DIVERTED & LANDED WITHOUT INCIDENT. MX ENSURED GEAR WAS LOCKED AND TOWED TO HANGAR FOR INSP AND FOUND THE LANDING GEAR DOWNLOCK SWITCH TO BE INOPERATIVE. REPLACED SWITCH, PN 487-862 IAW SRM 7-36; SWUNG GEAR MULTIPLE TIMES WITH GOOD RESULTS. SUBSEQUENT OPS CHECK-FLIGHT GOOD - ACFT RETURNED TO SERVICE.

FLAP PUSH PULL CONTROL CABLE, PN 9860058-7, WAS FOUND TO BE BINDING AND NOT MOVING SMOOTHLY IN ITS HOUSING. UPON REMOVAL OF CABLE, ALSO FOUND CRACKED T/E RIB, PN 0523233-6, DAMAGED AGAIN AFTER A VERY POOR PREVIOUS REPAIR. RIB WAS REPAIRED USING POORLY FORMED PATCHES, USING BLIND RIVETS THAT WERE OF AN INCORRECT LENGTH, AND PULLED NEARLY COMPLETELY THRU WHEN INSTALLED, LEAVING EXPOSED RIVET PULLING SHANKS AND INADEQUATE FORMED HEADS ON BACK OF BLIND RIVETS. IT WAS DISCOVERED THAT RATCHETING ACTION OF CABLE WAS PUTTING AN ELEVATED STRESS ON RIB, CAUSING IT TO VIBRATE SIDE TO SIDE WHEN FLAPS WERE ACTUATED. SUSPECT CABLE CONDITION EXISTED WHEN RIB WAS REPAIRED LAST, AND SINCE CABLE WAS NOT REPAIRED, PART CRACKED AGAIN. ORDERED AND INSTALLED NEW CABLE, ONLY TO FIND SAME RATCHETING ACTION EXISTED IN NEW CABLE RECEIVED FROM MFG. CURRENTLY AWAITING YET ANOTHER REPLACEMENT CABLE - THIS IS A CLIENT ACFT AND THIS IS THE FIRST ANNUAL INSP WE HAVE PERFORMED ON IT. IT APPEARS THAT AS THE CABLE MUST BE INSTALLED AND ROUTED, CABLE IS FORCED TO MAKE 2 SHARP 90 DEGREE BENDS THAT POSSIBLY EXCEED ITS BENDING RADIUS. GIVEN THE FIXED LENGTH OF THE CABLE AND THE STRUCTURE IT IS NOT POSSIBLE TO ROUTE THE CABLE ANY DIFFERENTLY TO REDUCE THE BEND RADII. THE FAILED RIB WAS REPAIRED POORLY, NOT BY US, BUT EVEN IF A NEW RIB WAS INSTALLED AND THE CABLE NOT FIXED, A NEW PART WOULD HAVE CRACKED AS WELL. REPLACED AND REINFORCED RIB. CABLE RUNS FROM SELECTOR HANDLE IN COCKPIT TO RT WING FLAP.

AIRCRAFT WRITTEN UP BY PIC FOR LARGE OIL LEAK, NR 2 ENGINE. INSPECTION REVEALED NR 3 CYLINDER (P/N LW-12966) HAD A GASKET (P/N 66732) INSTALLED INCORRECTLY UNDER ROCKER SHAFT COVER (P/N 72710). COVER IS SECURED WITH 2 SCREWS (P/N 72709). THIS ENGINE WAS RECEIVED FROM LYCOMING AS A FACTORY REMANUFACTURED UNIT AND ACCUMULATED ONLY 44.7 HRS TIS UNTIL LEAK WAS DISCOVERED. AFFECTED PARTS WERE INSTALLED BY MANUFACTURER AND NOT DISTURBED BY COMPANY PERSONNEL UNTIL DEFECT WAS DISCOVERED.

PILOT REPORTED RT PROP CONTROL INOPERATIVE. INSP REVEALED THAT THE BALL, PN 54175-00, CAME OUT OF THE SOCKET, PN 31747-00, ON THE RT PROP CONTROL END AT THE GOVERNOR. INSPECTED AND REPAIRED CONNECTION AT THE RT PROP GOV.

EXCESSIVE CAM LOBE WEAR IS CAUSING POWER LOSS AND EARLY REMOVAL OF SEVERAL OF OUR ENGINES. THIS ENGINE WAS THE EARLIEST REMOVAL SO FAR, WITH 744 HOURS REMAINING UNTIL O/H. HAVE BEEN IN CONTACT WITH MFG TECH SUPPORT FOR AN EXTENDED PERIOD OF TIME NOW AND HAVE YET TO FIND A SOLUTION. IT SEEMS THAT FOR SOME REASON USUALLY ONE CAM FOLLOWER WILL BECOME "PITTED" AND BEGIN TO ACCELERATE WEAR ON THE LOBE IT RIDES ON. NO IDEA WHAT IS CAUSING THE PITTING, OR HOW TO PREVENT IT.

ACFT OWNER REQUESTED CLEANING OF HIS FUEL INJECTORS, WHICH WE DID. ALMOST COMPLETED WITH THE TASK, TIGHTENING THE NUT FOR THE NR1 CYL FUEL INJECTION LINE, NOTICED THAT THE LINE WAS VERY LOOSE, AND UPON FURTHER INSP FOUND THAT THE RETAINING CLIP THAT WAS SUPPOSED TO SECURE THE LINE TO AN ENGINE BRACKET WAS FALLING OUT AND NOT DOING ITS JOB. ALSO, NOTICED SOME BLACK STAINING ON ADJACENT ENGINE STRUCTURE. WHEN LINE WAS REMOVED, FOUND THAT APPROX 1" OF THE TUBING HAD BEEN WORN AWAY TO ABOUT HALF THICKNESS, AND IT WAS LEAKING FUEL OVER THE TOP OF THE ENGINE. INSPECTED THE OTHER FUEL LINES, AND ALSO FOUND NR 2 CYL FUEL INJECTION LINE ON OPPOSITE SIDE OF ENG ALSO HAD DAMAGE, HOWEVER THIS WAS CAUSED BY IGNITION LEADS THAT WERE RUBBING AGAINST THE LINE. NR2 LINE DAMAGE WAS LESS SEVERE AND IT WAS NOT LEAKING, BUT IT WAS NOT SERVICABLE. ORDERED AND INSTALLED NEW LINES. SECURED NR1 LINE WITH HEAVIER DUTY TYPE ADEL CLAMP, AND SECURED ALL IGNITION LEADS TO PREVENT FURTHER CHAFFING.

EXCESSIVE CAM LOBE WEAR IS CAUSING POWER LOSS AND EARLY REMOVAL OF SEVERAL OF OUR ENGINES. THIS ENGINE WAS REMOVED AT 1650.2 TTSO WITH 549.8 REMAINING ON OUR 2200HR O/H INTERVAL. HAVE BEEN IN CONTACT WITH MFG TECH SUPPORT FOR AN EXTENDED PERIOD OF TIME NOW NAD HAVE YET TO FIND A SOLUTION. IT SEEMS THAT FOR SOME REASON USUALLY ONE CAM FOLLOWER WILL BECOME "PITTED" AND BEGIN TO ACCELERATE WEAR ON THE LOBE THAT IT RIDES ON. NO IDEA WHAT IS CAUSING THE PITTING OR HOW TO PREVENT IT. WE USE ONLY FACTORY REMANUFACTURED ENGINES IN OUR ENTIRE FLEET.

THIS VERNATHERM HAD A SHAFT AND NUT ASSY THAT WAS SECURED WITH A ROLL PIN. THE SHAFT FAILED AT ROLLPIN. THE NUT, SHAFT PIECE AT ROLLPIN TRAVELED THRU THE OIL GALLY AND LODGED AT A FITTING. HIGH OIL TEMP ALERTED US TO THIS FAILURE, OIL PRESSURE WAS NORMAL.(K)

INSTALLED NEW E-DRIVE STARTER ON THE LT SIDE. HAD MULTIPLE DISCREPANCIES WHERE PILOT NOTED THAT THE STARTER WOULD NOT ENGAGE THE SLIP RING. WHEN A MECHANIC WOULD INVESTIGATE THEY COULD NOT DUPLICATE THE PROBLEM. DURING A DETAILED INSPECTION IT WAS NOTED THAT THE LT ENGINE RING GEAR ON THE SLIP RING WAS SIGNIFICANTLY DAMAGED - RING WAS REPLACED AND WE ATTEMPTED TO CONTINUE TO USE THE STARTER BUT EVENTUALLY HAD TO REPLACE THE PART AS IT DOESN’T SEEM TO MATE CORRECTLY WITH THE GEAR. THE STARTER ITSELF STILL FUNCTIONS STRONGLY - HOWEVER IT SEEMS THE TEETH OF THE STARTER AND RING GEAR DO NOT LINE UP OR MESH CORRECTLY. IN LOOKING AT DOCUMENTATION - WE HAVE CONFIRMED THAT WE ARE USING THE CORRECT PITCH (12/14)RING GEAR (P/N 72566) FOR THIS MODEL STARTER AND IT IS APPROVED FOR USAGE ON THE AIRPLANE IN QUESTION.

PILOT NOTICED RT ENGINE OIL PRESSURE DROP AFTER CLIMBING THRU 24000 FT. HE SHUT THE ENGINE DOWN AS A PRECAUTIONARY MEASURE. THE PILOT LANDED WITHOUT FURTHER PROBLEMS. MAINTENANCE COMPLIED WITH A VISUAL CHECK OF THE ENGINE AND DID A FULL ENGINE RUN UP. THE AIRCRAFT WAS SENT ON AN OPERATIONAL CHECK FLIGHT AND NO PROBLEMS APPEARED. SUSPECT OIL COOLER CONGEALING, RESULTING IN HIGH OIL TEMPS AND LOW OIL PRESSURE WHICH CAUSED BOOST COMPONENTS TROUBLE MAINTAINING MANIFOLD PRESSURE. THE AIRCRAFT WAS RELEASED FOR FLIGHT OPS.

THE PILOT REPORTED INNER DOORS WOULD NOT RETRACT. TRIED TO EXTEND THE GEAR WITH THE LANDING GEAR HANDLE WITH NO RESULTS. THE GEAR WAS PUMPED DOWN WITH THE EMERGENCY GEAR HANDLE TO THE DOWN AND LOCKED POSITION, THEN LANDED WITHOUT FURTHER PROBLEMS. MAINT FOUND THE LT MAIN GEAR INNER DOOR ACTUATOR BOTTOM FITTING BROKEN OFF (PN AN837-D). THE FITTING WAS REPLACED AND THE ORIENTATION OF THE FITTING WAS IMPROVED TO PREVENT WHEEL STRIKE. THE ALIGNMENT OF THE FITTING IS CRITICAL TO PREVENT ANOTHER OCCURRENCE. THE AC WAS RETURNED TO SERVICE. (K)

WHILE PERFORMING A DETAILED INSPECTION OF THE RT PROPELLER ON 4/7/06. THE MECHANIC LUBING THE PROPELLER FOUND LIQUID BEING FORCED OUT OF THE ZERK HOLE BY THE GREASE BEING PUMPED INTO THE HUB. THE APPROXIMATE AMOUNT OF LIQUID WAS 2 TO 3 TABLESPOONS OF WHAT APPEARED TO BE TURBINE ENGINE OIL. PROP WAS REMOVED AND SENT TO A PROP OVERHAUL SHOP FOR FURTHER INVESTIGATION AND FOLLOW UP. (K)

ON 5/25/04, WHILE RETURNING, THE PILOT NOTICED AN INTERMITTENT LOSS IN MANIFOLD PRESSURE ON THE RT ENGINE. A GRADUAL LOSS OF OIL PRESSURE BEGAN TO DEVELOP SO THE PILOT SHUT DOWN THE ENGINE AS A PRECAUTIONARY MEASURE AND CONTINUED ON COURSE TO FAI. AIRPLANE LANDED WITHOUT PROBLEMS. MAINT THOROUGHLY INSPECTED THE ENGINE AND FOUND NO MAJOR DEFECTS. OIL WAS ADDED TO BRING THE LEVEL FROM FOUR TO ELEVEN QUARTS AND OPERATIONAL CHECK FLIGHT WAS CONDUCTED TO SEE IF THE PROBLEM PERSISTED. AFTER THE CHECK FLIGHT, THE OIL FILTER WAS REINSPECTED AND NO DEFECTS WERE NOTED. AIRCRAFT RETURNED TO SERVICE.

DURING DEPARTURE CLIMB OUT OF NONESSENTIAL ELECTRICAL ITEMS. HE INSREASED VENTILATION AS THE CO INDICATOR GOT DARKER INDICATING CO INCREASE. HE RETURNED AND LANDED WITHOUT FURTHER PROBLEMS ALTHOUGH HE DID EXPERIENCE A HEADACHE AND NAUSEA. MAINTENANCE REPLACED THE MUFFLER AND HEATER SHROUD ON THE LT SIDE. OPS CHECK FLIGHT WAS NORMAL.

IN THE SUPPLIED DOCUMENTATION FROM S-TEC WE HAVE BEEN ABLE TO FIND ANY INFORMATION ABOUT AUTOPILOT LOSS-IN-TURN AND OTHER CRITICAL LIMITS. THIS SEVERELY HAMPERS OUR ABILITY TO DETERMINE WHETHER OR NOT OUR AUTOPILOT IS OPERATING IN A CORRECT FASHION.

ON APPROACH, ON 10 NOVEMBER 2003, THE PILOT NOTICED FUEL FLOW FLUCTUATIONS AND AN ABRUPT LOSS OF OIL PRESSURE ON THE LT ENGINE AND IMMEDIATELY SHUT THE ENGINE DOWN. PILOT CONTINUED FLIGHT AND LANDED SAFELY WITHOUT FURTHER INCIDENT. PILOT IMMEDIATELY REPORTED THIS PROBLEM TO MAINTENANCE, WHO CAME IMMEDIATELY TO INVESTIGATE THE REPORTED DEFICIENCY. THE MECHANIC DISCOVERED THAT BOTH CASE HALVES WERE CRACKED IN THE VICINITY OF THE SHARED INTAKE CAME LOBE FOR NR 3 AND NR 4 CYLINDERS. FURTHER INVESTIGATION IS NECESSARY TO DETERMINE THE EXACT NATURE OF THE FAULT. WE ARE PROVIDING THIS AMENDMENT TO HELP EXPLAIN THE REASONS BEHIND THE SDR REPORT DATED 11/12/03 REGARDING THE ENGINE PROBLEMS. PURCHASED THIS ENGINE

LANDING GEAR WOULD NOT EXTEND WITH GEAR HANDLE. GEAR LOWERED AND LOCKED WITH EMERGENCY PUMP HANDLE. UPON EXAMINATION FOUND LOWER FITTING ON LEFT INNER GEAR DOOR ACTUATOR CRACKED AND HOSE CHAFED TO BOTTOM FITTING. THE PROBLEM SEEMED TO COME FROM A ACTUATOR HOSE THAT WAS SLIGHTLY TO LONG AND TIRE THAT HAS A LARGER DIAMETER THAN THE TIRES NORMALLY USED. WE ARE CYCLING THE LARGER TIRES OUT OF OUR SYSTEM. AIRCRAFT REPAIRED AND RETURNED TO SERVICE.

PREFLIGHT AND OPS CHECK OF TRIM SYSTEM NORMAL. 30 MINUTES INTO FLIGHT, PILOT NOTICED LIMITED RANGE IN ELEVATOR TRIM. PERFORMANCE DEGRADED AND TRIM JAMMED, MANUAL AND ELECTRIC. INSPECTION REVEALED WEAR ON THE JACKSCREW AND DRUM THREADS. PARTS WERE REPLACED AS REQUIRED. TOTAL TIME ON PART UNKNOWN BUT IS SUSPECTED TO BE CONSIDERABLE. RECOMMEND A SPECIAL INSPECTION TO INCLUDE DISASSEMBLY, INSPECTION, AND REPLACEMENT AS REQUIRED OF TRIM DRIVE MECHANISM PARTS AT EACH 1000 HOURS TIME IN SERVICE.

WHILE DEPARTING, ELEVATOR TRIM WHEEL JAMMED AND PILOT WAS UNABLE TO FREE SYSTEM. ELEVATOR TRIM WAS STUCK IN A NOSE DOWN CONFIGURATION. PILOT WAS ABLE TO COUNTERACT TRIM PRESSURES AND CONTINUED TO WHERE AIRPORT EMERGENCY CREWS WERE AVAILABLE. MAINTENANCE FOUND THE ELEVATOR TRIM JACK SCREW BOUND UP TO TRIM CABLE DRUM. JACK SCREW WAS DISCONNECTED FROM TAB AND FUNCTIONED WITH NO PROBLEMS. MAINTENANCE RERIGGED ELEVATOR TRIM SYSTEM IAW SM. FLIGHT CHECK WAS COMPLIED WITH GOOD RESULTS. AC WAS RELEASED TO OPERATIONS. INSPECTORS MET AC ON LANDING, INVESTIGATION WAS CONDUCTED, ACCUMULATIVE WEAR IN SYSTEM ALLOWED THE ELEVTOR TAB JACKSREW TO EXCEED ITS NORMAL LIMIT CAUSING THE JAM. NO RECENT WORK HAD BEEN DONE.

AIRCRAFT ENROUTE, MANIFOLD PRESSURE AND OIL PRESSURE STARTED DECENDING. AIRCRAFT LANDED. MECHANICS FOUND WASTEGATE LEAKING OIL FROM DRAIN. WASTEGATE REPLACED, TESTED ON RUNUP, WAS SATISFACTORY. AIRCRAFT RETURNED TO SERVICE.

FOUND DURING BASE INSPECTION, FATIGUED OVER THE YEARS, AGING AIRCRAFT PROGRAM PROBABLY APPLIES TO THIS PART. THE UPPER ATTACH POINT OF THE NOSE GEAR ACTUATOR ATTACHES TO THIS PART.

A REJECTED TAKEOFF. PILOT DETERMINED THAT THE RT ENGINE WAS NOT MAKING MANIFOLD PRESSURE OR RPM. AFTER RETURNING, IT WAS DISCOVERED THAT THE RT EXHAUST PIPE WAS BROKEN AT THE FLANGE. THE PIPE WAS REPLACED AND THE AIRCRAFT INSPECTED FOR EXHAUST DAMAGE. THE PLANE WAS RUNUP AFTER THE REPAIR AND OPERATIONS CHECK WAS NORMAL.

FOUND WHILE COMPLYING WITH AD. ON THIS ASSEMBLY, IT CAN BE SEEN THAT THE RED RUBBER VALVE DIAPHRAGM IS VISIBLE ON 3 SIDES ONLY. THE (IN) SIDE OF THE VALVE SHOWS THE DIAPHRAGM TO BE RECESSED PAST THE SEAL AREA OF THE CASTING. EITHER THE DIAPHRAGM WAS ASSEMBLED INCORRECTLY OR THE FASTENERS THROUGH THE VALVE BODY WERE OVER-TORQUED, MISSHAPING THE ADJUSTMENT CAP. CAP APPEARS TO BE WARPED, WHICH DOES NOT ALLOW DIAPHRAGM RUBBER TO SEAL.

GEAR HANDLE NOT RETURNING TO NEUTRAL. REMOVED PUMP AT 121.9 HOURS TSN.

FLIGHT DEPARTED, PILOT NOTICED FLAMES FLICKERING THROUGH THE INSPECTION DOOR ON THE LEFT ENGINE AFTER REDUCING POWER, HE NOTED NO OIL PRESSURE AND SECURED THE ENGINE. THE AIRCRAFT RETURNED TO AIRPORT WITHOUT FURTHER INCIDENT. IT WAS DISCOVERED THAT CONVERTER KIT LW-13904D HAD BEEN INSTALLED SEVERAL HUNDRED HOURS PRIOR WITHOUT THE TECHNICIANS KNOWLEDGE OF THE REQUIREMENTS OF MSB 543A SUPP NR1 ENGINE IS RETIRED FROM SERVICE.

DURING POST INSPECTION GROUND RUN, IT WAS OBSERVED THAT THE RIGHT ENGINE WOULD NOT RUN WITH OUT BOOST PUMP ASSISTANCE. WHEN REMOVED IT WAS NOTED THAT THE SHAFT ROTATED WITH ROUGHNESS. PUMP WAS REPLACED.

DURING INSPECTION EVENT FUEL WAS OBSERVED COMING OUT OF THE DRAIN FOR THE COMBUSTION HEATER. THE FUEL PRESSURE REGULATOR WAS REMOVED AND FOUND TO LEAKING FROM PARTING SURFACE. PART WAS REPLACED PER SB. RECOMMEND MACHING THE HOUSING AND USING AN (ORING TYPE SEAL).

PILOT COMPLAINED OF WING DE-ICE BOOTS STAYING INFLATED. REMOVED VALVE AND FOUND IT STUCK IN INFLATION MODE DUE EXCESSIVE SPACE BETWEEN THE GASKETS. THIS ALLOWS AIR PRESSURE TO VENT WHICH IS THE ACTUATION MODE FOR INFLATION. IT APPEARS THAT THE SQUEEZE ON THE RIVETS MAY BE TOO LIGHT. PART WAS REPLACED.

PILOT RETURNED FROM FLIGHT AND NOTIFIED MAINTENANCE OF AN OIL LEAK ON THE LEFT ENGINE. IT WAS DISCOVERED THAT A LEAK WAS COMING FROM NR 2 CYLINDER EXHAUST PUSHROD TUBE. WHEN THE TUBE WAS REMOVED A CRACK WAS FOUND APPROXIMATELY 4 INCHES FROM THE CYLINDER END. THE CRACK STARTED AT A DENT IN THE TUBE WHICH SEEMS TO BE FROM SHIPPING DAMAGE. AS THIS ENGINE WAS NOT SHIPPED IN STANDARD CRATE SUCH AS THE MFG USES. THE PART WAS REMOVED AND REPLACED.

DURING SCHEDULED INSPECTION FOUND DE-ICE WING LIGHT INOPERATIVE TROUBLESHOOTING REVEALED FAULTY DE-ICE VALVE, NEW VALVE, INOPERATIVE AS DELIVERED APPEARS THAT TOO MUCH AIR PRESSURE WAS DUMPING REPLACED VALVE.

DURING INSPECTION A LARGE PIECE OF CAST ALUMINUM WAS FOUND IN THE SUCTION SCREEN. THE ODD BANK OF CYLINDERS WERE REMOVED TO LOOK FOR DAMAGE. NR 6 CONNECTING ROD CAP WAS OBSERVED TO BE SCUFFED. SEVERAL ACCESSORIES WERE REMOVED AND NO DAMAGE WAS NOTED IN THE ACCESSORIES SECTION. ENGINE WAS REMOVED AND REPLACED TEAR DOWN REPORT PENDING.

DURING INSPECTION, THIS AREA WAS LOOKED AT AFTER FINDING OTHER AIRCRAFT WITH THIS CHANNEL CRACKED THE PART WAS REMOVED AND REPLACED. IT MAY BE THAT THE CUT OUT NOT BEING DRESSED TO RELIEVE THE STRESS CAUSED THE PART TO FAIL AS EXTRA STRESS IS INDUCED FROM THE NOSE GEAR ACTUATOR ATTACH BRACKETS , 2 REAR BOLTS COMING THROUGH THE CHANNEL. THE OUTBOARD ACTUATOR ATTACH HOLE WAS CRACKED FROM THE HOLE TO THE EDGE OF THE CHANNEL.

PILOT REPORTED HIGH CYLINDER HEAD TEMPERATURE AND RETURNED TO BASE. TECHNICIANS DISCOVERED A CRACK COMING OUT OF SPARK PLUG HOLE AN REMOVED INTERCYLINDER BAFFLING WHERE IT WAS FOUND TO RUN FROM SPARK PLUG HOLE TO FIRST COOLING FIN OF STEEL BARREL. THIS WHICH IS NR 6 POSITION WHICH EXPLAINS HIGH TEMPS. THERE APPEARS TO BE MACHINE MARKS IN AREA THAT ALLOWS INTAKE PUSH ROD TUBE TO PASS THROUGH THE COOLING FINS. THIS COULD NOT BE DETERMINED TO BE A CONTRIBUTING FACTOR. THE ASSEMBLY WAS REMOVED AND REPLACED. IN INSPECTION OF PUSHROD TUBE CUT-OUT AREA OF THE CYLINDER FINS (AS DISCUSSED ABOVE) IT IS NOTED THE CUT INTO THE MEAT OF THE CYLINDER HEAD WAS LEFT WITH A VERY SHARP EDGE. NO CHAMFER FOR STRESS RELIEF.

DURING INSPECTION EXHAUST STAIN WAS OBSERVED ON THE TURBOCHARGER MOUNT IN THE AREA WHERE THE TURBOCHARGER AND THE TRANSITION MEET AND FACE THE TURBO MOUNT. THE TURBO WAS REMOVED AND A CRACK WAS FOUND IN THE DIVIDE WHICH CAUSED THE TRANSITION TO WARP AND LEAK EXHAUST GASES. THE PART WAS REMOVED AND REPLACED.