THE FLIGHTSTAR CORPORATION

DURING CLIMBOUT AT APPROXIMATELY 42,000 FEET, CREW OBSERVED A LT ENGINE FIRE WARNING. THEY REDUCED POWER ON THE AFFECTED ENGINE AND THE WARNING CLEARED WITHOUT ANY FURTHER ACTION. CREW ELECTED TO RETURN TO BASE AND LANDED WITHOUT INCIDENT. AFTER LANDING, MAINTENANCE WAS UNABLE TO DUPLICATE THE WARNING ON THE GROUND OR IDENTIFY THE SOURCE. FIRE DETECTION SYSTEM TESTS NORMAL. AFTERBODY HAS BEEN REMOVED TO INSPECT FOR EVIDENCE OF FIRE, BLEED LEAK, OR DAMAGE FIRE DETECTOR, AND NO SUCH EVIDENCE CAN BE FOUND. EXCEPT THERE ARE MINOR NICKS ON HOT SECTION FIRE DETECTOR. FIRE DETECTORS TEST OK, PER LEARJET AMM. THERE IS NO SATISFACTORY WAY TO LEAK TEST THE HP BLEED MANIFOLD IN-HOUSE. MAINTENANCE PLAN IS TO REPLACE THE HOT SECTION FIRE LOOP AND THE HP BLEED MANIFOLD AS PRECAUTIONS AND THEN FLY THE AIRPLANE TO ENSURE THAT THE WARNING DOES NOT RECUR.

PILOT OBSERVED A CHIP DETECTION CAS MESSAGE ON THE ENGINE. SHORTLY AFTER, THE ENGINE SHUTDOWN WITHOUT BEING COMMANDED. FOUND SUBSTANTIAL DEBRIS ON THE CHIP DETECTOR AND IN OIL DRAINED FROM THE TRANSFER GEARBOX.

ON APPROACH TO HOME BASE THE CREW HAS AN APU FIRE WARNING. THEY RAN THE CHECKLIST & DISCHARGED THE EXTINGUISHER BOTTLE. SIMULTANEOUS TO DISCHARGING THE BOTTLE, THE WARNING INDICATOR WENT OUT. POST-FLIGHT, THERE WAS NO EVIDENCE OF A FIRE. OVERHEAT DETECTOR PN 17343-01-450F WAS FOUND TO HAVE A LOOSE CONTACT IN THE CERAMIC INSULATOR & WAS REPLACED WITH A NEW UNIT. NO OTHER DEFECT WAS FOUND IN THE FIRE DETECTION SYS.

RIGHT MAIN GEN FAILED IN FLIGHT. REPORTING THE EVENT BECAUSE WHEN THE GEN SEIZED, THE QUILL SHAFT DID NOT BREAK AWAY. THE GEN QAD MOUNT BROKE & THE GEN WAS FOUND ATTACHED BY THE WIRING & THE COOLING DUCT WITH THE QUILL SHAFT HANGING IN THE DRIVE ADAPTER RECESS & SUPPORTING THE DRIVE END. THERE WAS SLIGHT DAMAGE TO THE ACCESSORY DRIVE FOR THE UNIT, BUT IT IS POSSIBLE THAT THIS COULD HAVE BEEN WORSE AS THE MOUNT GAVE WAY & THE SHAFT CAME OUT OF ITS DRIVE SPLINES OR HAD THE GEN COME COMPLETELY LOOSE. PHOTOS WILL BE SENT.

AFTER LANDING, WHEN THRUST REVERSERS WERE DEPLOYED, CREW OBSERVED RT ENGINE FIRE WARNING. IN FOLLOWING CHECKLIST PROCEDURES, ENGINE WAS SHUTDOWN, FIRE HANDLE PULLED, AND BOTH BOTTLES DISCHARGED. FIRE INDICATION REMAINED, SO AIRPLANE WAS EVACUATED (CREW ONLY, THERE WERE NO PAX). THERE WAS NO FIRE - FALSE INDICATION. CAUSE WAS DETERMINED TO BE A MALFUNCTIONING CREW WARNING PANEL. REPLACEMENT PANEL WAS INSTALLED, AND OPS TESTED NORMAL.

MAINTENANCE WAS HAVING ERRATIC INDICATIONS WHEN SERVICING HYDRAULIC FLUID. WHEN SERVICED CORRECTLY PER MM, HYDRAULIC LOW FLUID OR OVER FILLED MESSAGES FROM EICAS WOULD APPEAR SHORTLY THEREAFTER. THERE WAS NO EVIDENCE OF FLUID LOSS AND MECHANICS WERE PROPERLY TRAINED AND EQUIPPED FOR THE SERVICING TASK. HYDRAULIC FLOAT SWITCH WAS REMOVED FOR TROUBLESHOOTING AND WAS FOUND TO HAVE ONE FLOAT BROKEN. FLOAT SWITCH ASSEMBLY WAS REPLACED WITH NEW UNIT AND HYDRAULIC SYSTEM CHECKED IN CONSULTATION WITH LEARJET FIELD SUPPORT TO ENSURE POSSIBILTY OF SYSTEM CONTAMINATION WAS ADEQUATELY ADDRESSED. PHOTO OF BROKEN SWITCH ASSEMBLY WILL BE SENT.

DURING CRUISE FLIGHT, PILOTS OBSERVED NR1 ENGINE OIL PRESSURE FLUCTUATIONS. PRESSURE SUBSEQUENTLY DROPPED TO 25 PSI. AT THAT TIME, PILOTS PERFORMED PRECAUTIONARY SHUTDOWN AND DIVERTED FOR PRECAUTIONARY LANDING. MX FOUND OIL LEAKING FROM FLANGE OF ADAPTER AT FUEL HEATER OIL OUTLET. O-RING OR EQUIVALENT IAW TFE731-3, IPC 73-10-04, FIG 3 ITEM 25D WAS FOUND TO BE PART CAUSING LEAK. FURTHER INVESTIGATION OF O-RING FOUND IT TO BE CONFORMING TO CLAMPED PROFILE, BUT STILL SOFT/SUPPLE. INSPECTION BY BENDING THE O-RING REVEALED CRACKING OF THE MATERIAL. FAULTY O-RING AND OTHER SEALS REMOVED FOR ACCESS WERE REPLACED WITH NEW AND SUBSEQUENT RETURN TO SERVICE CHECKS WERE NORMAL. ENGINE REQUIRED 5 PINTS OF OIL TO REACH NORMAL OPERATING LEVEL. TIME SINCE INSP NOTED BELOW IS TIME SINCE "MAJOR PERIODIC INSPECTION."

FLIGHT CREW EXPERIENCED A THUD SOUND AND SETTLING OF THE NLG AT TAKEOFF ROTATION. AMBER NWS FAIL CAS MESSAGE ILLUMINATED AFTER TAKEOFF AND GEAR IN TRANSIT LIGHTS REMAINED ILLUMINATED AFTER RETRACTION. FOLLOWING THE NWS FAIL CHECKLIST DID NOT CORRECT THE INDICATIONS, AFTER SECOND RETRACTION OF GEAR THE IN TRANSIT LIGHTS REMAINED ON. FLIGHT CREW ELECTED TO CONTINUE TO HOME BASE AT A SPEED BELOW VLE AND LANDED WITHOUT INCIDENT WITH THREE GREEN INDICATIONS FOR LANDING GEAR. NLG SHOCK ABSORBER WAS OBSERVED FULLY COMPRESSED AFTER LANDING, AND TIRE SCUFF MARKS WERE FOUND ON THE LT SIDE OF THE NLG WELL AREA. NLG STRUT P/N 4532210000-V16-005 S/N 418 WAS REPLACED WITH A NEW UNIT, SAME P/N S/N 492. ALL FTS WERE NORMAL. PAINT TOUCHED UP AT SCUFF MARKS IN WHEEL WELL AREA. STRUT WAS NOT DISASSEMBLED, BUT DURING REMOVAL, IT APPEARED THAT THE INTERNAL CENTERING CAM DID NOT FUNCTION. THERE WAS NO SIGN OF LEAKAGE BEFORE OR AFTER THIS EVENT, AND STRUT EXTENSION WAS NORMAL AT PREFLIGHT. REMOVED STRUT WAS SENT TO LEARJET SPARES AS A CORE AND A TEARDOWN REPORT REQUESTED. PART TIME 444.5 HOURS/442 LANDINGS SINCE NEW AT REMOVAL.

TIRE WAS OBSERVED TO HAVE BULGES ALONG THE EDGE RADIUS OF THE TREAD WHILE TRACTOR-TOWING THE AIRPLANE. THE BULGES BEGIN ABOUT 0.75 INCH ON THE TREAD SURFACE AND WRAP AROUND ONTO THE SIDEWALL A SIMILAR DISTANCE. OTHER THAN BULGES, THE TIRE WAS NORMAL--NEARLY WORN OUT, BUT STILL AIRWORTHY. THERE IS NO SIGN OF EXTERNAL DAMAGE TO THE TIRE AND NO PILOT REPORTS OF ABNORMAL OPERATION. THERE IS NO DAMAGE TO THE AIRPLANE OR THE WHEEL ASSEMBLY. AFFECTED WHEEL ASSEMBLY WAS REMOVED AND REPLACED WITH A SERVICEABLE UNIT. TIRE HAS BEEN RETAINED FOR POSSIBLE INVESTIGATION AND TIRE VENDOR AND AIRPLANE MFG HAVE BEEN NOTIFIED.

NR 3 MLG TIRE TREAD SEPARATED FROM THE CASTING ON LANDING. TREAD DAMAGED UNDERSIDE OF RIGHT INBOARD FLAP AND RIGHT LOWER COWL. TIRE APPEARED TO BE PROPERLY INFLATED AND NOT EXCESSIVELY WORN. TIRE DID NOT DEFLATE AFTER SEPARATION. TIRE S/N 91570060. SUBMITTER RECOMMENDED CHECKING WITH GOODYEAR TO SEE IF THEY ARE AWARE OF OTHER SEPARATIONS. (X)