CORPORATE AIR

Operated by Corporate Air (per NTSB report)

Operated by Corporate Air (per NTSB report)

Operated by Corporate Air (per NTSB report)

SMOKE IN COCKPIT ON TAKEOFF.

G600 PFD INOP 1-2 MIN DURING FLIGHT

AFTER TAKEOFF, THE PILOT EXPERIENCED DIFFICULTY TURNING RIGHT TO THE ASSIGNED HEADING, FULL RIGHT RUDDER AND TRIM WAS NEEDED TO MAINTAIN CONTROL. DECLARED AN EMERGENCY AND RETURNED TO DEPARTURE WITHOUT INCIDENT. MAINTENANCE INSPECTED THE ACFT AND FOUND THAT A RUDDER CABLE IN THE REAR OF THE PLANE HAD BROKEN.

MIDWAY THROUGH FLIGHT, ON THE EMPTY STAGE LEG, THE PILOT NOTICED OIL APPEARING IN THE OIL PRESSURE GAUGE. ALL ENGINE INDICATIONS WERE NORMAL THE FLIGHT CONTINUED TO DESTINATION, WHEN THE STAGE FLIGHT GOT CLOSER TO THE AIRPORT, THE PILOT SAW THAT OIL HAD FILLED THE GAUGE AND WAS ALSO COMING OUT OF THE CO-PILOTS YOKE AND DRIPPING. DECLARED AN EMERGENCY AND WAS GIVIEN DIRECT CLEARANCE TO LAND. ON LANDING THE LOW OIL PRESSURE GAUGE BEGAN FLASHING AND THEN CAME ON SOLID, THE ACFT WAS SHUTDOWN.

LEFT OUTBOARD FLAP TRACK HAS SEVERE EXFOLIATION CORROSION.

RIGHT OUTBOARD FLAP TRACK HAS SEVERE EXFOLIATION CORROSION.

RIGHT CENTER FLAP TRACK HAS SEVERE EXFOLIATION CORROSION.

DURING AIRCRAFT REPOSITIONING, RIGHT BRAKE LINE FAILED, LOOSING BRAKE FLUID AND LOSS OF BRAKING ON RT BRAKE.

ON FINAL APPROACH, TURNED ON LANDING LIGHTS & SMELLED BURNING WIRE, SHUT OFF ALL LIGHTS, LOOKED OUTSIDE SAW LEFT LANDING LIGHT ON, SWITCH WAS OFF.

BUSS 1 ALL 3 ROWS ALL CIRCUIT BREAKERS TRIPPED, ENGINE FIRE LIGHT ILLUMUNICATED, WENT OUT ON TAXI IN, ELECTRICAL BURNING ODOR.

AN OVERWHELMING BURNING ODOR IN THE COCKPIT. STBY POWER LIGHT CAME ON, NO CHARGE, LOAD FROM GENERATOR.

REMOVED LT WING INBD FLAP, DUE TO CORROSION ON FLAP TRACK GREATER THAN 15%.

ALL BUS NR 1 POWER BREAKERS POPPED IN FLIGHT. ICE DETECTOR, LIGHT ICE LIGHT FLASHING FAIL LIGHT ON, ENG FIRE WARNING LIGHT, STBY POWER ON & VAC LOW LIGHT.

AIR RETURN DUE TO BUS POWER CB'S POPPED ON FIRST 5 ROWS.

WHILE AT CRUISE ALTITUDE OF 7000 FEET, DURING FLIGHT, THE RT HALF OF THE CHIP DETECTOR LIGHT ILLUMINATED. THE CREW ELECTED TO RETURN FOR MX TROUBLESHOOTING. INSPECTED CHIP DETECTOR & FOUND NO METAL BRIDGING & PROPER FUNCTION CHECK OF DETECTOR UNIT. FOUND TKS ANTI-ICE FLUID INFILTRATION INTO ELEC CONNECTOR. R & R ELEC CONNECTOR & RAN ACFT FOR 45 MIN WITH NO FURTHER INDICATION PROBLEM. ACFT RETURNED TO SERVICE.

DURING PHASE INSPECTION, FOUND THE COWLING BRACKET ASSEMBLY SEVERELY CORRODED & REQUIRES REPLACEMENT.

DURING PHASE INSPECTION, PLAY BETWEEN THE LT & RT ELEVATORS WAS NOTED. UPON FURTHER INSPECTION, FOUND THE LT ELEVATOR TORQUE TUBE RIVETS WORKING.

AT 18000 MSL WHILE EN ROUTE, THE CREW ENCOUNTERED SEVERE ICING CONDITIONS & THE WIND SCREEN ICED OVER. THE TKS SYS WAS IN HIGH MODE & WOULD NOT CLEAR THE ICE. WHEN MAX MODE WAS SELECTED THE YELLOW TKS CAUTION LIGHT ILLUMINATED, KEPT THE TKS SYS HIGH MODE. ELECTED TO DECLARE AN EMER TO RECEIVE PRIORITY. AFTER DESCENDING BELOW 10000 FEET, THE WINDSCREEN CLEARED UP & REMAINED CLEAR FOR THE REMAINDER OF THE FLIGHT. ENCOUNTERED ICE AT 12000 & ICE WAS CLEARING WITH TKS SYS IN HIGH MODE, GOT ON TOP AT 16000 & ICING CONDITIONS CEASED FOR A PERIOD OF TIME. AGAIN ENCOUNTERED LIGHT TO MODERATE & WAS STILL CLEARING IN HIGH MODE. REQUESTED 18000 & ICING CONDITIONS WERE NON-EXISTENT FOR A PERIOD OF TIME WHEN SEVERE ICING CONDITIONS WERE ENCOUNTERED. GND SPEED WAS APPROX 80 KNOTS AS A RESULT OF 50 - 60 KNOT HEADWINDS. DECLARED EMER APPROX 15 MILES FROM THE MALTT INTERSECTION. APPROX 4 GALLONS OF TKS FLUID REMAINED AFTER ARRIVAL, FULL AT DEPARTURE.

FAILED NDI DUE TO CORROSION BEYOND MAX REPAIRABLE LIMITS.

STBY POWER ON ANNUNCIATOR ILLUMINATING IN CLIMB WITH 2ND CB OF POWER 2 BUS & 3RD CB OF POWER 1 BUS POPPED.

DURING AN ATTEMPTED RT TURN DURING TAXI OUT TO THE RUNWAY FOR A TRAINING FLIGHT, THE CREW ADVISED THEY WERE UNABLE TO MAKE THE RT TURN & REQUESTED A RETURN TO THE CARGO RAMP. UPON ARRIVING IN THE CARGO AREA, THE CREW ADVISED AIRCRAFT LOST BRAKING ABILITY & WERE ABLE TO STOP THE ACFT USING BETA & REVERSE. UPON ENG SHUTDOWN THE ACFT MOVED FWD APPROXIMATELY 10 FEET AS THE CREW PULLED THE THROTTLE OUT OF BETA FOR SHUTDOWN WITH FULL BRAKES APPLIED & THE EMERGENCY BRAKE SET. ACFT WAS PUSHED BACK INTO THE TIE DOWN SPOT & SECURED. NO EMERGENCIES WERE DECLARED & NO DAMAGE WAS SUSTAINED TO THE ACFT.

CORROSION FOUND ON CTR FLAP TRACK WEB, LS FOUND OUT OF LIMITS. AREA FOUND TO BE SEVERE INTERGRANULAR CORROSION.

CORROSION FOUND ON OTBD FLAP TRACK WEB, LS FOUND OUT OF LIMITS. AREA FOUND TO BE SEVERE INTERGRANULAR CORROSION.

CORROSION FOUND ON OTBD FLAP TRACK WEB RS FOUND OUT OF LIMITS. AREA FOUND TO BE SEVERE INTERGRANULAR CORROSION.

CORROSION FOUND ONCENTER FLAP TRACK WEB, R.S. FOUND OUT OF LIMITS. AREA FOUND TO BE SEVERE INTERGRANNULAR CORROSION.

CORROSION FOUND ON INBD FLAP TRACK WEB RS FOUND OUT OF LIMITS. AREA FOUND TO BE SEVERE INTERGRANULAR CORROSION.

CORROSION FOUND ON INBD FLAP TRACK WEB, LS FOUND OUT OF LIMITS. AREA FOUND TO BE SEVERE INTERGRANULAR CORROSION.

CORROSION FOUND ON OTBD FLAP TRACK WEB, LS FOUND OUT OF LIMITS. AREA FOUND TO BE SEVERE INTERGRANULAR CORROSION.

FLIGHT 8573. DURING CLIMB OUT, ATTEMPTING TO TRIM ACFT VIA ELECTRIC TRIM BUT WHEEL WOULD NOT TURN. ATTEMPTED TO TURN TRIM WHEEL MANUALLY BUT WHEEL WOULD SNAP BACK TO STARTING POSITION. ELECTED TO RETURN TO DEPARTURE.

PILOT REPORTED HE RAN OUT OF THROTTLE AT 5800 FEET -TORQUE LIMITED WITH NORMAL ITT.

PILOT REPORTED HE RAN OUT OF THROTTLE AT 5800 FEET WITH NORMAL ITT. ENGINE WAS RE-RIGGED AND OPS CHECK FLIGHT WAS SATISFACTORY.

FLT 248, PILOT REPORTED THAT WHILE DESCENDING FROM 8000 TO 3000 FT APPROX 30 NM OF DESTINATION, THE ELEVATOR TRIM FAILED. DECLARED AN EMERGENCY, PILOT REPORTED THAT THE CREW "MUSCLED" THE ACFT WHERE THEY LANDED WITHOUT FURTHER INCIDENT. FOUND TRIM CABLE BROKEN.

INSTALLED TKS SYS IAW SK208-174B. DURING FLOW CHECK, FOUND PROPORTIONING VALVE MALFUNCTIONING. INTERNAL CHECK VALVE INOP, LETTING FLUID IN LINES TO PANELS BLEED BACK INTO TANK. IAW OPS CHECK, THE CHECK CAN BE DONE 3 TIMES. THE VALVE FAILED EACH TIME. REPLACED VALVE WITH ANOTHER NEW VALVE WHICH THEN PASSED THE FLOW CHECK. THIS IS THE PROPORTIONING VALVE IN THE AFT FUSELAGE THAT FEEDS THE STABILIZER PANELS.

INSTALLED TKS SYSTEM IAW SK208-174B. DURING FLOW CHECK, FOUND PROPORTIONING VALVE MALFUNCTIONING. INTERNAL CHECK VALVE INOP, LETTING FLUID IN LINES TO PANELS BLEED BACK INTO TANK. IAW OPS CHECK, THE CHECK CAN BE DONE 3 TIMES. THE VALVE FAILED EACH TIME. REPLACED VALVE WITH ANOTHER NEW VALVE WHICH THEN PASSED THE FLOW CHECK. THIS IS THE PROPORTIONING VALVE IN THE AFT FUSELAGE THAT FEEDS THE RT WING AND STRUT PANELS.

PILOT REPORTED LT ENGINE WOULD ONLY PRODUCE 1600 LBS OF TORQUE AT MOST. THE TAKEOFF WAS ABORTED AND ACFT RETURNED TO THE PARKING RAMP WITHOUT FURTHER INCIDENT AND MX WAS NOTIFIED. MX TROUBLESHOT ACFT AND PERFORMED THE FOLLOWING MX. TROUBLESHOOT PY LINES AND FILTER - CHECKS GOOD. CAPPED FUEL CONTROL UNIT AND TESTED LINES - CHECKED GOOD. MX FOUND A FAULTY NR1 PROP GOVERNOR TO BE THE CAUSE. MX R & R FAULTY PROP GOVERNOR IAW MM 61-20-00 AND SD3-30 MM 71-00-02. MX PERFORMED ENGINE RUN FUNCTIONAL AND LEAK CHECKS AND ALL WERE GOOD. ACFT RETURNED TO SERVICE.

DURING MX, CORROSION INSPECTION, FOUND CORROSION ON LT WING OTBD SIDE OF NR 1 NACELLE INBD T/E BETWEEN WS 160 & 175. MX REMOVED LT WING UPPER SKIN DOUBLERS AT WS 160 AT APPROX 7.5" FROM L/E SPAR AND APPROX 7.5" FROM THE REAR EDGE SPAR. ON REMOVAL AND FURTHER INSPECTION OF WING BAY AREA, FOUND CORROSION ON INTERNAL WING SUPPORT U CHANNELS, TEE SUPPORT FITTINGS AND SUPPORT BRACKETS. FABRICATED WING SKIN DOUBLERS IAW SD3-30 SRM 57-09-5, FIG 1. FABRICATED SUPPORT U CHANNELS IAW SRM 57-09-5, FIG 1. REMOVED THE INTERNAL SUPPORT LT BRACKETS AT WS 160. FABRICATED SUPPORT L BRACKETS AT WS 160. FABRICATED SUPPORT LT BRACKETS IAW SRM 51-30-00. REMOVED BUTT STRAP AT WS 160 FROM LEADING EDGE SPAR TO T/E SPAR, FABRICATED BUTT STRAP IAW SRM 51-30-00 AND SHORTS DWG SD360-578-11C. REMOVED BUTT STRAP FILLERS AT WS160. FABRICATED BUTT STRAP FILLERS IAW SRM 51-30-00. ALL MATERIAL FABRICATED WERE CLEANED, TREATED AND PRIMED AND PAINTED IAW SRM 51-23-00. INSTALLED FASTENERS AND WING SKIN DOUBLERS AND BUTT STRAP ON LT WING UPPER SURFACE AT WS 160 IAW DWG SD3-30-6535 / SD360-57-11/C.

PILOT REPORTED DURING TAKEOFF ROLL OF FLIGHT 8687-THAT HE EXPERIENCED A SEVERE VIBRATION AND ABORTED THE TAKEOFF ROLL AND THAT HE TAXIED THE ACFT BACK TO THE PARKING RAMP WITHOUT ANY ADDITIONAL INCIDENT. MX TROUBLESHOOT AND INSPECTED ACFT TO INCLUDE MLG MOUNTING POINTS, ENGINE MOUNTING COLLAR WITH NO DISCREPANCIES FOUND IAW MM 5-50-00. MX FOUND THE NNLG TIRE OUT OF ROUND AND ALSO FOUND A FAULTY SHIMMY DAMPENER. MX R & R NOSE WHEEL AND TIRE ASSY AND R & R THE SHIMMY DAMPENER AND COMPILED WITH SK208-164A LORD SHIMMY DAMPENER SERVICE KIT INSTALLATION - MX DONE IAW MM 32-40-00 AND SK208-164A. OPS AND FUNCTIONAL CHECKS COMPLETED WITH NO FURTHER DEFECTS NOTED.

PILOT REPORTED THAT ON CLIMBOUT, NOTICED THE AILERON TRIM SEEMED TO BE FROZEN AND FELT LIKE IT WAS BINDING. WHEN TRYING TO ADJUST IT WOULD ONLY MOVE A LITTLE AND THEN SPRING BACK RIGHT AWAY. PILOT DECIDED TO RETURN TO DEPARTURE AND LANDED WITHOUT FURTHER INCIDENT. EMERGENCY WAS NOT DECLARED. MX VERIFIED DISCREPANCY AND MOVED ACFT TO THE HANGAR AND ALLOWED IT TO WARM UP IN THE HANGAR. MX COMPLIED WITH MM INSPECTION TASK 27-10-02-640 (AILERON TRIM LUBRICATION) IAW MM 12-21-00, SECTION 3, TABLE 1. AILERON TRIM ACTUATOR FUNCTIONAL AND OPS GROUND CHECKED GOOD, SYS MOVES FREELY AND CORRECT. ACFT WAS RELEASED FOR AN OPS CHECK FLIGHT. OPS CHECK FLIGHT WAS COMPLETED AND AILERON TRIM CHECKS WERE GOOD IN ALL PHASES OF FLIGHT. ACFT RETURNED TO SERVICE.

ON SHORT FINAL AT APPROX 1000 FT, CREW HEARD THE FIRE DETECTION WARNING HORN CHIRP AND THE FIRE DETECTION WARNING LIGHT WAS FLICKERING INTERMITTENTLY. THE CREW ADVISED ALL ENGINE PARAMETERS INDICATED NORMALLY AND NO EVIDENCE OF FIRE WAS DETECTED. NO EMERGENCY WAS DECLARED AND THE ACFT LANDED WITHOUT FURTHER INCIDENT. MX TROUBLESHOT ACFT AND INSPECTED FIRE DETECTION SYS. MX R & R FIRE DETECTOR CONTROL BOX IAW MM 26-10-00. ADDITIONAL TROUBLESHOOTING ON THE FIRE DETECTION SYS FOUND A CHAFED WIRE DOWN-LINE OF THE FIRE WARNING SWITCH. MX REPAIRED THE CHAFED WIRE IAW WIRING DIAGRAM 20-10-00 AND ALL OPS AND FUNCTIONAL CHECKS WERE GOOD.

PILOT REPORTED AN ADC FAILURE, LOSS OF AIRSPEED, ALTIMETER, VERTICAL SPEED, TAS AND OAT DISPLAYS DURING CRUISE. AIRCRAFT LANDED WITHOUT INCIDENT. MX TROUBLESHOOT AND INSPECTED ACFT AHRS 1 TAS ALERT IAW STC ICAW A0-01080-05, REV 1 AND REFERENCING FLIGHT-LINE MM A0-00601-05, REV A, PAGE 3-13. MX RESET GTP-59 AND GDC-74 CONNECTOR PLUGS AND PERFORMED GROUND OPS AND FUNCTIONAL CHECKS AND SELF-TESTS. ALL CHECKS WERE GOOD. ACFT RETURNED TO SERVICE - THREE FLIGHTS HAVE BEEN COMPLETED WITH NO FURTHER DEFECTS NOTED.

PILOT REPORTED AT CRUISE FLIGHT, AT APPROX 6000 FT, DURING STAGING FLIGHT, THE CREW ADVISED THE FIRE DETECTION SYS ACTIVATED INTERMITTENTLY IN FLIGHT. THE CIRCUIT BREAKER WAS RESET AND THE SYS WOULD DEACTIVATE FOR APPROX 10 MINUTES AND THEN REACTIVATE. ARRIVED INTO DESTINATION WITHOUT INCIDENTAND NO EVIDENCE OF FIRE WAS NOTED AFTER THE ACFT WAS SECURED. MX TROUBLESHOT AND INSPECTED FIRE DETECTION SYSTEM AND FOUND DEFECTIVE TEST SWITCH. MX R & R DEFECTIVE TEST SWITCH IAW MM 26-10-00, ALL GROUND OPS AND FUNCTIONAL CHECKS WERE GOOD.

AFTER TAKEOFF, THE FIRE DETECTION WARNING HORN SOUNDED AND THE FIRE DETECTION WARNING LIGHT ILLUMINATED. CREW DECLARED AN EMERGENCY AND RETURNED TO DEPARTURE, LANDING AT 17:13 ZULU WITHOUT FURTHER INCIDENT. CREW REPORTED THAT THERE WAS NO INDICATION OF FIRE AFTER SECURING THE ACFT. MX INSPECTED THE ENGINE FIRE DETECTION SYSTEM AND FOUND MULTIPLE INSULATORS OUT OF THE BRACKETS, RE-INSTALLED INSULATORS IN BRACKETS. MX ALSO FOUND FIRE WIRE TOUCHING REDUCTION GEARBOX CASE AND THE INERTIAL SEPARATOR BRACKET, REPOSITIONED FIRE LOOP WIRE. ALL WORK PERFORMED IAW MM 26-10-00. PERFORMED ENGINE RUN WITH NO DEFECTS NOTED.

PILOT REPORTED DURING A MX CHECK FLIGHT THAT THE GEAR REMAINED DOWN WITH ALL THREE GREEN LIGHTS ILLUMINATED WHEN THE GEAR HANDLE WAS MOVED TO THE UP POSITION. ACFT RETURNED TO DEPARTURE UNEVENTFULLY. MX TROUBLESHOT THE GEAR SYS AND THE FOLLOWING MX WAS PERFORMED. TROUBLESHOOT AND FOUND BROKEN WIRE ON LANDING GEAR SWITCH (RT SIDE). R & R RT SIDE LANDING GEAR SWITCH IAW 32-30-00 GEAR PROBLEM STILL NOT CORRECTED. TROUBLESHOOT PRINTED CIRCUIT BOARD (TIME DELAY). R & R PCB PROBLEM STILL WAS NOT CORRECTED. TROUBLESHOOT ALL WIRING IN LANDING GEAR SYS AND FOUND BAD GROUND TO HYD POWER PACK ASSEMBLY -GROUND CABLE. CLEANED AND TIGHTENED POWER PACK GROUND CABLE AND PERFORMED NUMEROUS OPERATIONAL AND FUNCTIONAL CHECKS TO INCLUDE EMERGENCY EXTENSION/ MANUAL SYS CHECKS. ALL OPS AND FUNCTIONAL CHECKS WERE GOOD. OPS CHECK FLIGHT COMPLETED AND NO FURTHER DEFECTS FOUND OR NOTED. ACFT RETURNED TO SERVICE.

PILOT REPORTED DURING PRE-FLIGHT, PRE-TAXI CHECKS THAT THE GNS-530W GPS/NAV/COM UNIT WAS INOPERATIVE AND THAT HE SMELLED A SMOKE ODOR. ACFT WAS SHUTDOWN AND MX WAS NOTIFIED. MX INSPECTED AND TROUBLESHOT SYS AND R & R GNS-530W GPS/NAV/COM UNIT WITH SERVICEABLE UNIT IAW FE G600 GNS 530W/430W GMA 347, CHAPTER 2.7.9 AND 4.2/4.3 AND 5.5.1 AND 5.5.3. GNS 530W UNIT SYS FUNCTIONAL AND OPS CHECKED GOOD.

PILOT REPORTED THAT WHILE ENROUTE, DECLARED AN EMERGENCY WHEN A PIECE OF THE NR 2 PROPELLER BLADE DE-ICE BOOT SEPARATED FROM THE PROP. CREW NOTICED A SLIGHT DROP IN ENGINE OIL PRESSURE BUT REMAINED IN THE NORMAL RANGE. AS A RESULT THE CREW ELECTED TO DIVERT FOR SAFETY REASONS THINKING THAT THE ENGINE WAS RUNNING ROUGH/ VIBRATIONS. CREW ADVISED THAT THE PLANE WAS RUNNING ROUGH WHEN THEY TAXIED INTO THE RAMP. MX WAS NOTIFIED AND TECHS WERE DISPATCHED TO INSPECT AND REPAIR ACFT. MX INSPECTED ACFT AND PERFORMED THE FOLLOWING: PERFORMED FORIEGN OBJECT DAMAGE INSPECTION - NO DEFECTS WERE NOTED OR FOUND - IAW MM 5-50-00. MX R & R NR 2 ENGINE BLADE PROP DE-ICE BOOT IAW MM 30-60-00. NR 2 PROP DE-ICE BOOT DAMAGED/ MISSING- APPROX 3" ON BOOT. PERFORMED ENGINE GROUND PERFORMANCE RUN-UP AND FOUND OIL PRESSURE GOOD AND NO VIBRATIONS FROM ENGINE OR PROP - IAW MM 71-00-00. ALL OPS CHECKS WERE GOOD - ACFT RETURN TO SERVICE.

AFTER FLIGHT, WHEN PILOT APPLIED LT BRAKE, THERE WAS NO RESPONSE AND ENGINE REVERSE HAD TO BE USED TO GET THE ACFT STOPPED. THE LT BRAKE STARTED WORKING AFTER BEING PUMPED SEVERAL TIMES AND THE PILOT WAS ABLE TO MANEUVER THE ACFT INTO IT'S PARKING SPOT WITHOUT FURTHER INCIDENT. MX WAS NOTIFIED AND DISPATCHED TO ISN (WILLISTON ND) TO INSPECT AND REPAIR ACFT. MX INSPECTED AND TROUBLESHOT ACFT BRAKE SYS. MX R & R LT BRAKE MASTER CYLINDER WITH SERVICEABLE UNIT IAW MM CHAPTER 32-41-00 PARA AB. BRAKES AND MASTER CYLINDER BLED AND OPS AND FUNCTIONAL CHECKS WERE GOOD. ACFT RETURNED TO SERVICE.

AFTER LEVELING OFF AT 9,000 FT, CREW OBSERVED A FLAME COME OUT OF NR 1 ENGINE, FOLLOWED BY THE GENERATOR LIGHT ILLUMINATING, AND ENGINE SPOOLING DOWN. FOLLOWED EMERGENCY CHECKLIST AND SHUTDOWN NR 1 ENGINE IN-FLIGHT. ATTEMPTED TO RESTART NR 1 ENGINE PER EMERGENCY CHECKLIST, WHICH WAS UNSUCCESSFUL. DECLARED AND EMERGENCY AND DIVERTED. LANDED WITHOUT ANY FURTHER INCIDENT. DURING POSTFLIGHT, OBSERVED OIL LEAKING OUT THE BOTTOM OF COWLING. FOUND FUEL OIL HEATER HOUSING CRACKED, OIL LEVEL AT APPROXIMATELY 4, FOUND COMPRESSOR SEIZED. POWER SECTION CHIP DETECTOR INSPECTED AND FOUND VERY FINE DEBRIS ON CHIP DETECTOR.

FLIGHT 8974, PRECAUTIONARY LANDING AND AN EMERGENCY DECLARED EN-ROUTE DUE TO A FLUCTUATING OIL PRESSURE GAUGE. PILOT ADVISED OIL PRESSURE GAUGE FLUCTUATED +/- 4 DURING FLIGHT, THEN LEVELED OFF AT 5,000 MSL. ACFT LOST SOME OIL PRESSURE, BUT MAINTAINED IN THE GREEN ARC. ON LANDING AND ROLL OUT, OIL PRESSURE GAUGE DECREASED TO APPROX 65 PSI AND IT WAS IN THE YELLOW CAUTION ZONE ARC. MX R & R OIL PRESSURE GAUGE IAW MM 79-30-00. REMOVED AND CLEANED AND REINSTALLED ENGINE OIL FILTER IAW MM 79-20-00. ENGINE RUN OPS AND LEAK CHECKED GOOD - OIL PRESSURE IN THE GREEN ARC ALL RANGES.

AFTER TAKEOFF, TOWER ADVISED CREW THAT THE MAIN UPPER CARGO DOOR WAS OPEN AND THAT THE INTERIOR DOOR LINING DEPARTED THE ACFT. THE CREW DID NOT HAVE A DOOR ANNUNCIATOR LIGHT INDICATION THAT THE DOOR WAS OPEN AND RETURNED TO DEPARTURE IMMEDIATELY, BUT DID NOT DECLARE AN EMERGENCY. AFTER ARRIVAL, CREW CONFIRMED THAT THE MAIN UPPER CARGO DOOR WAS OPEN. MX INSPECTION AND TROUBLEHOOTING SO FAR INCLUDES DETAILED VISUAL INSPECTION OF CARGO DOOR IAW MM 52-00-00 WITH NO DEFECTS NOTED, OPS AND FUNCTIONAL CHECKED NORMAL. PERFORMED A DETAILED INSPECTION OF FUSELAGE FRAME, NO DEFECTS NOTED. MX REPLACED DOOR LINER IAW MM 52-31-00, REV 8. MX INSPECTED AND RESET CARGO DOOR LIGHT ANNUCIATOR WARNING LIGHT IAW MM 52-71-00, REV 6. NO DEFECTS NOTED.

PILOT REPORTED THAT AFTER TAKEOFF AND UPON RETRACTION OF THE LANDING GEAR, THE RT NOSE GEAR INDICATED UP AND LOCKED AND THE LT MAIN GEAR INDICATED DOWN AND LOCKED. PILOT ELECTED TO RETURN TO DEPARTURE. GEAR WAS SELECTED DOWN AND 3 DOWN AND LOCKED LIGHTS ILLUMINATED. LANDING WAS UNEVENTFUL. AT NO TIME WAS A GEAR UNSAFE INDICATION RECEIVED. INSPECTED LANDING GEAR SYSTEM VISUALLY WITH NO STRUCTURAL DEFECTS NOTED. OPEN