N257AS

Part: SOCKET — DEFECTIVE (ANNUNCIATOR) · airframe 44,387 hrs · 45,495 cycles

AFTER DEPARTURE FROM KDFW, LEFT ENGINE FIRE WARNING FLICKERED. THE AIRCRAFT RETURNED TO KDFW AND LANDED WITHOUT INCIDENT. MAINTENANCE PERFORMED TROUBLESHOOTING RESULTING IN REMOVAL AND REPLACEMENT OF FIRE LOOP DETECTOR P/N 3601-72-540/235C-5.3M. OPS CHECK GOOD. A/C FLEW AGAIN ON 10/19/22. DURING CLIMB OUT FROM KDFW THROUGH 12000, L ENGINE DET INOP PIPE ZONE BEGAN FLICKERING. NO SINGLE CHIME OR MASTER CAUTION HEARD OR SEEN. ANNUNCIATOR CONTINUED TO ILLUMINATE INTERMITTENTLY UNTIL BELOW 6000 FT. THE AIRCRAFT RETURNED TO KDFW AND LANDED WITHOUT INCIDENT. MAINTENANCE TROUBLESHOT, REMOVED AND REPLACED ALARM LIGHT CONTROLLER PN 70-0274-3. OPS CHECKS FAILED. ALL WIRES CHECKED OUT GOOD. MAINTENANCE SLAVED IN FIRE CONTROL MODULE AND PROBLEM PERSISTED. MAINTENANCE THEN ISOLATED IT DOWN TO AND REMOVED AND REPLACED ANNUNCIATOR SOCKET DS0431. TAXIED AIRCRAFT AND RAN ENGINES FOR 45 MINUTES. COULD NOT DUPLICATE ISSUE. OPS CHECK GOOD.

Part: A/C PACK — OVERHEATED · airframe 43,025 hrs · 43,764 cycles

DISCREPANCY: AFTER TAKING OFF FROM KPHX, THE CREW REPORTED DURING CLIMB THAT SMOKE WAS COMING OUT OF THE AIR VENTS. AFTER RUNNING THROUGH QRH THE CREW MADE THE DECISION TO RETURN TO KPHX. THE CREW STATED, SMOKE GOGGLES WEREN’T NECESSARY. INITIALLY THEY DIDN'T DECLARE AN EMERGENCY, HOWEVER, UPON HEARING THEY HAD SMOKE IN THE COCKPIT, ATC DECLARED IT FOR THEM. THEY RETURNED TO BASE AND LANDED WITHOUT ISSUE. CORRECTIVE ACTION: MAINTENANCE RAN AIRCRAFT AND TURNED BOTH PACKS ON. THE SYSTEM PRODUCED HOT AIR IMMEDIATELY. MAINTENANCE SET PACKS TOO COLD POSITION AND COOLED DOWN SYSTEM FOR ABOUT 15 MINUTES. AFTER COOLING DOWN, MAINTENANCE RAN ENGINES TO TAKEOFF POWER FOR 20 MINUTES. THE SYSTEM PRODUCES HOT AIR WITH BOTH PACKS ON. MAINTENANCE NOTED NO SMOKE AND WAS NOT ABLE TO DUPLICATE DISCREPANCY. SUSPECT PACKS MAY HAVE BEEN BRIEFLY OVERHEATED. THE AIRCRAFT WAS RELEASED AND RETURNED TO SERVICE. NO ISSUES HAVE BEEN REPORTED ON ANY SUBSEQUENT FLIGHT.

Part: WIRE — BROKEN · airframe 41,628 hrs · 42,159 cycles

SHORTLY AFTER TAKEOFF, THE PILOT OBSERVED THE LT ENG, DUCT LEAK ANNUNCIATOR LIGHT ILLUMINATED & AURAL WARNING SOUNDED. THE PILOT FOLLOWED PROCEDURES IN QRH & PERFORMED PRECAUTIONARY IN FLIGHT SHUT DOWN OF THE LT ENG. PILOT DECIDED TO RETURN & LANDED WITHOUT FURTHER INCIDENT. TROUBLESHOOTING FOUND BROKEN WIRE ON LT SIDE FRAME 24 SENSOR & WAS RUBBING ON THE SENSOR. REPAIRED WIRING AT LT SIDE FRAME 24 SENSOR & LT SIDE FRAME 25 SENSOR. PERFORMED GND RUN OF THE LT ENG. ALL ENG INDICATIONS WERE NORMAL.

Part: DUCT — BLOWN (BLEED AIR SYS) · airframe 39,348 hrs · 40,280 cycles

THE PILOT REPORTED THAT ON CLIMBOUT FROM KOPF A RIGHT ENGINE DUCT LEAK WARNING LIGHT ILLUMINATED. THE PILOT FOLLOWED THE QUICK REFERENCE HANDBOOK AND SHUT DOWN THE RIGHT ENGINE. DECLARED AN EMERGENCY, RETURNED TO KOPH AND LANDED WITHOUT INCIDENT. MAINTENANCE INSPECTED THE RIGHT BLEED AIR DUCTS AND FOUND DUCT P/N 120-24942-001 BLOWN OUT IN A SIX INCH AREA. REMOVED AND REPLACED THE DUCT.

Part: BATTERY — INOPERATIVE (FUSELAGE)

DURING A HANGAR CHECK IN MCN, THE FORWARD SEGMENT OF EMERGENCY LIGHTS WERE FOUND TO BE INOPERATIVE. MAINTENANCE REMOVED AND REPLACED THE NR 1 EMERGENCY LIGHT BATTERY. OPERATIONAL CHECKS GOOD. AIRCRAFT OK FOR SERVICE. (M)

Part: BUTT STRAP — CORRODED (FUSELAGE)

DURING C CHECK INSPECTION, THE CENTER BUTT STRAP WAS FOUND CORRODED BEYOND LIMITS BETWEEN FRAMES 16 AND 21 AS WELL AS BETWEEN STA 6653.1 AND FRAME 26. MAINTENANCE REMOVED AND REPLACED THE CORRODED SECTIONS OF BUTT STRAP IAW SRM.

Part: BUTT STRAP — CORRODED (FUSELAGE)

DURING (C) CHECK INSPECTION, THE LEFT BUTT STRAP, BETWEEN FRAMES 14 AND 21, WAS FOUND TO BE CORRODED BEYOND LIMITS. MAINTENANCE REMOVED AND REPLACED THE CORRODED BUTT STRAP IAW SRM.

Part: CROSSBEAM — CORRODED (FUSELAGE OB, IB)

DURING (C) CHECK INSPECTION, CORROSION WAS DISCOVERED ON THE LEFT HAND INBOARD AND OUTBOARD CROSS BEAMS AT FRAME 16. MAINTENANCE REMOVED AND REPLACED THE TWO CORRODED LEFT HAND CROSS BEAMS IAW SRM.

Part: CROSSBEAM — CORRODED (FUSELAGE)

DURING (C) CHECK INSPECTION, CORROSION WAS FOUND ON TOP OF THE LEFT HAND CROSSBEAM AT FRAME 28. MAINTENANCE REMOVED AND REPLACED THE CORRODED CROSSBEAM IAW SRM.

Part: STRINGER — CRACKED (WING)

DURING HANGAR MAINTENANCE IN BNA, THE RIGHT MOST INBOARD FORWARD STRINGER WAS FOUND CRACKED IN TWO PLACES AT THE FUEL PANEL JUST INBOARD OF THE NACELLE. MAINTENANCE REPAIRED THE CRACKED STRINGER IAW SRM 57-20-03. THE DAMAGED SECTION WAS CUT OUT AND A SPLICE WAS INSTALLED REFERENCING SRM 51-22-00. NO LEAKS WERE NOTED. (M)

Part: WIRE — BROKEN (CABIN)

DURING HANGAR INSPECTION IN TXK, MAINTENANCE FOUND A BROKEN WIRE ON THE EMERGENCY EXIT SIGN AT ROW 8. MAINTENANCE REPAIRED THE BROKEN WIRE ON THE ROW 8 EMERGENCY EXIT SIGN. AIRCRAFT OK FOR SERVICE. (M)

Part: FRAME — CORRODED (FUSELAGE)

DURING INSPECTION IN TXK, MAINTENANCE FOUND CORROSION ON FRAME 21 IN BETWEEN STRINGER 19 RIGHT AND 19 LEFT. MAINTENANCE REPAIRED CORROSION IAW ASA EO 120-53-0159, WHICH OUTLINE THE REPAIR SPECIFICATIONS FOR THIS OCCURRENCE. (M)

Part: ACM — MALFUNCTIONED (AC BAY)

FLT 4916 - DURING FLIGHT FROM HOU TO DFW, CAPTAIN REPORTED BOTH PACKS ONLY PRODUCING WARM TO HOT AIR AND A STORNG BURNING SMELL OF PLASTIC. AIRCRAFT LANDED SAFELY IN DFW. MAINTENANCE REMOVED AND REPLACED LEFT PACK ACM. OPERATIONAL CHECKS GOOD. AIRCRAFT RETURNED TO SERVICE. (M)

Part: FRAME — CRACKED (ENGINE NACELLE)

DURING C-CHECK INSPECTION, THE NR 1 ENGINE FRAME WAS FOUND CRACKED IN THE UPPER INBOARD TORQUE TUBE MOUNT WEB. POSSIBLE CAUSE, FATIGUE FROM ENGINE TORQUE. (X)