ROYAL AIR FREIGHT, INC.

Operated by ROYAL AIR FREIGHT INC (per NTSB report)

Operated by ROYAL AIR FREIGHT INC (per NTSB report)

Operated by Royal Air Freight, Inc (per NTSB report)

Operated by ROYAL AIR FREIGHT INC (per NTSB report)

THE AIRCRAFT EXPERIENCED A CABIN DEPRESSURIZATION AT FL390. THE CREW WAS ABLE TO MAINTAIN THE CABIN ALTITUDE AT BELOW FL100 (10,000 FEET) WITH THE EMERGENCY AIR AND WINDSHIELD HEAT VALVES. THE CREW ELECTED TO DON THEIR O2 MASK AND ASK FOR A EMERGENCY DESCENT. THE AIRCRAFT LANDED UNEVENTFULLY AT FINAL DESTINATION.

PILOT REPORTED THE HEATER WAS INOPERATIVE. TROUBLESHOOTING FOUND THE HEATER FUEL PUMP HAD FAILED, AND THAT IT WAS PUMPING FUEL OUT AROUND THE PUMP SHAFT. (X)

LOST CABIN PRESSURE FL250, COULD NOT MAINTAIN CABIN IN EITHER AUTO OR MANUAL AT ALTITUDE. REPLACED THE WATER SEPARATOR SOCK AND ANTI-ICE PRESSURE REDUCING VALVE FILTER. OPERATIONAL CHECKS GOOD ON GROUND. AIRCRAFT RETURNED TO SERVICE. (M)

HYDRAULIC FILTER ASSY CUP CRACKED AT THREADS ON RT ENGINE. MOST FLUID LOST. GEAR HAD TO BE PUMPED DOWN BY HAND. RT ENGINE DRIVEN PUMP ALSO FAILED SEVERAL HOURS LATER. SUSPECT FROM LACK OF FLUID.

CRACK IN AIRFRAME ACROSS AREA WHERE FLAP HINGE BRACKET BOLTS ON. FOUND ON RT WING, OUTBOARD FLAP SEGMENT, INBOARD MOUNT. CRACK VISABLE WITH NAKED EYE. CRACK 1.25 INCHES LONG, BOTH DOUBLER AND SKIN. TOTAL TIME AIRFRAME: APPROXIMATELY 6,805.4 HOURS.

WHILE ON SHORT FINAL, LEFT FIRE WARNING ILLUMINATED. MAINTENANCE INSPECTED AND FOUND BROKEN WIRE AT TERMINAL END AT OUTBOARD FORWARD THERMOCOUPLE. REPLACED TERMINAL END SYSTEM. OPS CHECKED OK.

LANDING GEAR WOULD NOT RETRACT AT TAKEOFF. SERVICE NOSE STRUT SHOCK ABSORBER IAW MM 32-21. LEAK AND OPERATIONAL CHECKS GOOD. AIRCRAFT RETURNED TO SERVICE. (M)

DURING ROUTINE ELT CHECK, FOUND THE ELT HAD A WEAK SIGNAL. ELT WAS REPAIRED, RECERTIFIED, AND NEW BATTERY BY NARCO ON 12-21-95. BATTERY DUE OFF DATE IS JANUARY 17, 1998. A REPLACEMENT BATTERY WAS TRIED, BUT DID NOT FIX THE PROBLEM.

THE FIRST COIL EXPLODED BREAKING OFF THE TOP OF THE IGNITOR AND BREAKING WIRES IN THE IGNITION UNIT SPEWING 'OIL' FROM INSIDE THE COIL THROUGHOUT THE HEATER BAY. THE REPLACEMENT COIL SHORTED OUT, LEAKED OIL, AND THE COVER CAME LOOSE.

HEATER FOUND INOPERABLE. FOUND THE IGNITION COIL HAD EXPLODED. THE END CAP HAD COME OFF WITH ENOUGH FORCE THAT IT BENT THE IGNITER OVER; THE OPPOSITE REACTION CAUSED THE COIL CAN TO GO AFT AND BREAK WIRES OFF MISCELLANEOUS PARTS IN THE COIL COVER. THE MOST SIGNIFICANT POINT WAS THAT FUEL WAS STILL BEING PUMPED INTO THE HEATER, BUT NOT BEING IGNITED.

THESE MCCAULEY PROPELLERS COME PLACARDED TO LUBE TORQUE TO 40-45 FEET/POUNDS. THE CESSNA MM SPECIFIES 80-85 FEET/POUNDS DRY TORQUE. THE CESSNA TECH SAID BOTH ARE ACCEPTABLE, BUT DO NOT MIX THE TWO. TECH SAID 80 POUNDS LUBE TORQUE WILL PULL THE STUD OUT OF THE HUB. THIS COULD BE CONFUSING, AND HAS CAUSED EXPENSIVE PROBLEMS.

LOSS OF HYDRAULIC PRESSURE DUE TO CRACKED T-FITTING. (X)

DURING A 100-HOUR INSPECTION, THE ELEVATOR BELLCRANK PIVOT BOLT WAS FOUND LOOSE, WHICH CAUSED WEAR ON THE BELLCRANK SUPPORT BRACKET. THIS WAS CAUSED BY THE PIVOT COMING LOOSE AND ALLOWING THE BOLT TO WORK IN THE SUPPORT BRACKETS. (X)

YIP - GEAR WOULD NOT RETRACT AFTER TAKEOFF. YIP FOUND CANNON PLUG TO 9G NOT COMPLETELY SECURE - SWUNG GEAR SEVERAL TIMES. OPS CHECK GOOD. AIRCRAFT RETURNED TO SERVICE.

INTERNAL FAILURE OF NOSE GEAR DOWNLOCK SWITCH ALLOWED INDICATOR LIGHT VOLTAGE TO BLEED OVER TO THE LANDING GEAR CONTROL SECTION OF THE SWITCH. (X)

VERTICAL STABILIZER FORWARD SPAR ATTACH FITTING AT FUSELAGE, FOUND CORRODED. (X)