AIRPAC AIRLINES, INC.

PILOT DEPARTED THE MORNING OR MARCH 31 2023 AND SHORTLY INTO HIS FLIGHT, REPORTED AN ELECTRICAL BURNING SMELL. TURN BACK WAS PREFORMED AND FLIGHT RETURNED TO AIRPORT WHERE MAINTENANCE WAS READILY AVALLABLE. AFTER INVESTIGATION FOUND THO ELECTRICAL CONNECTOR FOR THE PROPELLER ANTI-ICE CONTROL TIMER HAD MELTED. REPAIRED THE WLRE PER CAB0011. OPS CHECKED ON GROUND WITH NO DEFECTS NOTED.

ON CLIMB OUT FROM FAT THE PILOT HEARD A "POP" AND THEN FELT A VIBRATION IN THE AIRFRAME. HE NOTIFIED ATC OF HIS NEED TO RETURN ASAP AND LANDED WITH OUT INCIDENT. UPON INSPECTION MAINTENANCE FOUND APPROXIMATELY 4" OF THE NR 3 BLADE DEICE BOOT MISSING. ALL THREE BOOTS WERE RECENTLY REPLACED DURING ROUTINE MAINTENANCE AND WAS THE SECOND FLIGHT SINCE INSTALLATION. MAINTENANCE REMOVED ALL THREE BOOTS AND REPLACED FOR A SECOND TIME. THE AIRCRAFT WAS RETURNED TO SERVICE AND REPOSITIONED TO PDX. UPON ARRIVAL IN PDX 2 OF THE THREE BOOTS HAD SIGNS OF DISTRESS AND APPEARED TO BE "SLIPPING". CONTACT HAS BEEN MADE WITH THE MANUFACTURER.

DURING NIGHT/IMC CONDITIONS, AND WHILE BEING VECTORED FOR THE ILS FINAL APPROACH, THE LEFT BOOST PUMP LIGHT ILLUMINATED. CONFIRMED BOTH BOOST PUMP SWITCHES WERE ON, ENGAGED BOTH EMERGENCY BOOST PUMP SWITCHES. APPROXIMATELY 10 SECONDS LATER, THE ENGINE BEGAN TO SURGE. SENSING EITHER PENDING ENGINE FAILURE OR SIMPLE FUEL STARVATION, SWITCHED BOTH TANKS TO THE INBOARD POSITION. THE LEFT ENGINE CONTINUED TO SURGE, IT SEEMED ANY ATTEMPT TO RESTORE FUEL FLOW WOULD BE UNSUCCESSFUL, FOLLOWED SINGLE ENGINE FAILURE PROCEDURES, SECURED THE ENGINE, DECLARED AN EMERGENCY AND CONTINUED THE FINAL APPROACH TO A SUCCESSFUL SINGLE-ENGINE LANDING. ON INSPECTION, DEBRIS WAS FOUND IN THE METERING ORIFICE. CLEANING AND SUBSEQUENT ENGINE PERFORMANCE RUNS FOUND THE ENGINE OPERATION NORMAL AND THE AIRCRAFT RETURNED TO SERVICE.

CYLINDER NR 6 HAD BROKEN BOTH EXHAUST ROCKER SHAFT STUDS. HAPPENED ON SAME CYLINDER APPROXIMATELY 200 HOURS AGO ON A FACTORY CYLINDER WITH 1000 HOURS. PUSH ROD IS NOT BENT, LIFTER DOES NOT SHOW ANY SCORING. OUR ASSUMPTION IS THE LIFTER HYDRAULICALLY LOCKED AND PUT EXCESSIVE PRESSURE ON THE ROCKER CAUSING THE STUDS TO BREAK.

ON 08/05/2012 WHILE EN ROUTE FROM OGG TO KOA, THE PILOT SMELLED AN ELECTRICAL SMELL (BUT NO SMOKE) COMING FROM BEHIND THE CIRCUIT BREAKER PANEL. THE PILOT TRIPPED OFF THE GENERATOR AND SWITCHED OFF THE STANDBY POWER AND CONTINUED THE FLIGHT ON BATTERY POWER. THE SMELL QUICKLY DISSIPATED. UPON EXAMINATION, THE ALTERNATOR CONTROL UNIT WAS FOUND TO BE THE PROBLEM, IT HAD SMOKE DAMAGE AND WHITE ASH LOOKING RESIDUE ON IT.

ON PREFLIGHT, THE PILOT FOUND THE STABILATOR TO BE EXTREMELY LOOSE AND NOTIFIED MX. WHEN REMOVED TAIL CONE FOUND A BROKEN BOLT ON THE RT THAT HAD BACKED OUT. IMMEDIATELY GROUNDED THE WHOLE FLEET UNTIL SUCH TIME AS WE COULD INSPECT ATTACHING POINTS, BEARINGS AND REPLACE ATTACHING HARDWARE. WHEN WE STARTED REMOVING BOLTS FROM OTHER ACFT, FOUND SEVERAL THAT WERE PITTED AND SCORED. THE BOLT THAT BROKE HAD BEEN ON ACFT AT LEAST SINCE 06/22/07 WITH 2350 FLIGHT HOURS ON IT.

RIVETS ON RIGHT SIDE (LOWER RIGHT) SHEARED WHERE AFT SPAR OF VERTICAL STABILIZER ATTACHES TO EMPENNAGE. THIS IS AIRCRAFT NR 4 IN FLEET OF PA34-200T'S THAT HAS BEEN INSPECTED AND FOUND TO HAVE THIS DISCREPANCY.

BOTH LOWER RIVETS (LT AND RT) WERE FOUND SHEARED ON THE AFT SPAR OF THE VERTICAL STABILIZER WHERE THE VERTICAL STABILIZER ATTACHES TO THE EMPENNAGE. SUBMITTER STATED THIS IS AIRCRAFT NR 3 IN FLEET OF PA 34-200T'S THAT HAS BEEN FOUND TO HAVE THIS PROBLEM.

DURING A SCHEDULED INSPECTION IN MSP, MAINTENANCE FOUND ON RIGHT HORIZONTAL STABILIZER LOWER SKIN JUST OUTBOARD OF BL 72.43 AT LOCATION OF PREVIOUS REPAIR, A 3.5 INCH HORIZONTAL CRACK. REMOVED PREVIOUS REPAIR AND EXAMINED PREVIOUS DAMAGE AND FOUND A 1.5 INCH CRACK, TOTAL CRACK LENGTH IS 5 INCHES. FABRICATED AND INSTALLED A SURFACE REPAIR DOUBLER, 8.5 INCH BY 7 INCH, ONTO LOWER SKIN IAW FAC SRM 55-90-10 PGS 21-23, REV NOV 5/93. (M)

INSPECTION FOUND FLAP LEVER BRACKET IS CRACKED AT BOTH FORWARD BEND RADIUS.

A 6 INCH PIECE OF THE OUTBOARD WHEEL HALF WAS FOUND BROKEN OFF.

MSP - DURING AN INSPECTION, MAINTENANCE FOUND 3 CRACKS IN RT VERTICAL STABILIZER SKIN ALONG FORWARD AUXILIARY SPAR RIVETS MEASURING .380 INCH AT WL 140.0, .880 INCH AT WL 144.0, .750 INCH AT WL 148.0. REPAIRS WERE COMPLETED BY STOP DRILLING CRACKS AND INSTALLING A 2024 T-3 .032 INCH DOUBLER MEASURING 4.0 INCHES BY 12.0 INCHES. COMPLETED IAW AEROTECH DESIGNS EO NR 01-96033. (X)

MSP - DURING INSPECTION, MAINTENANCE FOUND THE RT BUSHING LOOSE IN ELEVATOR AFT SPAR FITTING, PN 27-43042-001. REPAIRS WERE COMPLETED BY REAMING BUSHING HOLE IN FITTING, FABRICATING AND INSTALLING BUSHING MADE TO NAS75 STANDARDS. ALL WORK DONE IAW EA 01-96034. (X)