R-985Pratt & Whitney R-985 Wasp Junior

Parts most often named Cylinder (44) · Cylinder Head (35) · Piston (8) · Stud (7)

DURING CRUISE FLIGHT, ENGINE LOST PARTIAL POWER. PILOT TURNED AROUND TO RETURNED, COULD NOT MAINTAIN ALTITUDE, AND LANDED. DURING TAXIING THE ENGINE DIED. PILOT NEVER TRIED TO RESTART ENGINE AND THE AIRCRAFT WAS TOWED. NO VISIBLE DAMAGE TO THE AIRCRAFT. INVESTIGATION FOUND THE NR 8 CYLINDER EXHAUST VALVE PUSHROD BROKEN AT ROCKER ARM END. THE PUSHROD WAS REPLACED AND THE ENGINE IS RUNNING GOOD.

(CAN) DURING AN INSPECTION FOR METAL CONTAMINATION FOUND AT A SCHEDULED INSPECTION, THE NR 8 CYLINDER EXHAUST VALVE GUIDE WAS FOUND TO HAVE COME LOOSE AND WAS BEING STRUCK BY THE EXHAUST VALVE. THE CYLINDER PN 399353, [S/N removed] WAS REMOVED WITH 1104.0 TSO, AND REPLACED WITH A [S/N removed] CYLINDER, PN SAME, [S/N removed] WITH TSO 292.6 TREM 1207.4. ALL WORK WAS PERFORMED MM. GROUND RUN AND LEAK CARRIED OUT, NO DEFECTS.

(CAN) DURING INSPECTION FOUND FOUR FAILED STUDS ON NR 3 CYLINDER ASSEMBLY. ALSO CRACK WAS SEEN ON FRONT CRANK CASE ADJACENT TO THE CYLINDER.

Parts most often named Crankshaft (6) · Crankcase (6) · Connecting Rod (5) · Pin (4)

(CAN) DURING CRUISE, THE ENGINE HAD HIGH VIBRATIONS FOR COUPLE OF SECONDS AND THEN THE ENGINE STOPS SUDDENLY. THE PILOT DID AN EMERGENCY LANDING. THE AME`S FOUND THE CYLINDER NR 5 BEEN PUNCTURED BY CONNECTING ROD. ENGINE OVERHAUL SHOP ACKNOWLEDGED THE PROBABLE CAUSE IS THE FAILURE OF THE MASTER CONNECTING ROD. ENGINE OIL SAMPLE WAS SENT FOR FURTHER INVESTIGATION.

ON INSPECTION OF THE OIL SCREEN IT WAS NOTICED THAT THERE WAS FOREIGN MATERIAL IN THE OIL SCREEN. THIS MATERIAL WAS TAKEN TO AN O/H SHOP FOR ANALYSIS. WE WERE INSTRUCTED TO PULL 1 CYLINDER AND LOOK AT THE THE MAIN BEARING AND NOTICED THAT A PIECE OF IT WAS MISSING. THE ENGINE WAS PULLED AND REPLACED.

(CAN) A PROBLEM WITH CONNECTING ROD ON CYLINDER NR 5 CAUSED AN ENGINE FAILURE DURING DESCENT AFTER PARA-DROP. ENGINE WAS FEATHERED AND AIRPLANE LANDED SAFELY.

Parts most often named Magneto (7) · Drive Gear (3) · Gear (3) · Distributor Gear (2)

(CAN) DURING THE SECOND GROUND RUN ON AN O/H ENGINE, THE ENGINEER SELECTED RT MAGNETO, THE ENGINE RPM DECAYED, AND WAS FOLLOWED BY A LOUD BACKFIRE. THE ENGINEER SELECTED BOTH MAGNETOS AND THEN SHUT ENGINE DOWN. AFTER AN INSPECTION, THE RT INTERNAL DRIVE GEAR HAD FOUND TO HAVE FAILED. TIME ON THE MAG WAS 0.0 TSO. THE RT MAGNETO, PN SB9RU-3, [S/N removed] WAS REPLACED WITH AN O/H MAGNETO, PN SB9RU-3, [S/N removed] IAW MM. GROUND RUN PROCEDURES CARRIED OUT AND THE ACFT WAS RETURNED TO [S/N removed].

LT MAGNETO SEAL - PART OF BLOWER ASSY APPEARS TO HAVE SHRUNK ALLOWING SEAL TO LEAK IN 4 BOLT HSG PLATE PN 164315. PERHAPS THE ENGINE OIL IS NOT COMPATIBLE WITH THE SEAL MATERIALS. SB 1266 EXPLAINS THIS ASSEMBLY.

(CAN) DURING CRUISE OPERATIONS, THE ENGINE WAS NOTED AS RUNNING ROUGH. THE AIRCRAFT RETURNED TO THE MAINTENANCE FACILITY FOR INVESTIGATION. INSPECTION REVEALED A UNSERVICABLE DISTRIBUTOR GEAR. MAGNETO REMOVED FROM [S/N removed].

Parts most often named Carburetor (9) · Screw (3) · Shaft (2) · Layshaft (1)

(CAN) THE ROLL PIN ATTACHING THE CARBURETOR MIXTURE CONTROL ARM TO THE ASSY WAS ABLE TO BACK OUT FAR ENOUGH TO MAKE CONTACT WITH THE MIXTURE STOP. NO SECONDARY SAFETY, LOCKWIRE WAS FOUND RETAINING THIS ROLL PIN ON THIS ASSEMBLY OR ANY REMAINING UNITS IN STOCK.

DURING AN INSPECTION, AME FOUND THROTTLE CONTROL VERY STIFF, DISCONNECTED THROTTLE CONTROL AND FOUND SHAFT IN CARB PARTIALLY SEIZED, CARB REPLACED.

DURING ACCIDENT INVESTIGATION ALLEGATIONS WERE MADE THAT THE AMO SIGNED A MX RELEASE FOR WORK ON AN ACFT THAT HAD UNAPPROVED PARTS. DURING THE AMO`S INVESTIGATION IT BECAME APPERENT THAT VERY FEW, IF ANY OF THESE ACFT HAVE THE PART INSTALLED THAT CONFORMS WITH THE MFG DRAWINGS.

Parts most often named Engine (12) · Carburetor (1) · Nut (1) · Sump (1)

DURING TAKEOFF ONCE THE AIRCRAFT REACHED 100 FT, THE ENGINE SEIZED. PILOT MADE AN EMERGENCY LANDING BACK AT AIRPORT. ENGINE WAS REMOVED AND ANOTHER INSTALLED. OPEN

(CAN) (AIRCRAFT ON FLOATS) DURING TAXI OUT FOR TAKE OFF, ENGINE STARTED TO POP AND BACKFIRE WHICH CREATED ENGINE FAILURE. CARB REPLACED AND IS CURRENTLY BEING INVESTIGATED. (NOTE: RT MAGNETO ALSO REPLACED)

(CAN) SHORTLY AFTER TAKEOFF, ENGINE BACKFIRED, HESITATED AND CLEARED ITSELF 4 TIMES IN SUCCESSION.PILOT PERFORMED EMERGENCY LANDING AT BRAMPTON AIROPORT, WAS UNABLE TO LOWER GEAR IN TIME, AND LANDED ON FLOAT KEELS. DAMAGE TO FLOATS KEELS SUSTAINED. CAUSE OF BACKFIRING UNDER INESTIGATION, FOLLOW-UP REPORT WILL BE ISSUED.

Parts most often named Blade (11) · Clamp (2) · Bearing (1)

PROPELLER RECEIVED FROM CUSTOMER WITH APPROX 5" OF BLADE MISSING FROM NR2 BLADE TIP ([S/N removed]). PROPELLER DISMANTLED, CLEANED, CLAMPS AND HUB SPIDER MPI INSPECTED, BLADES LPI INSPECTED (IAW MFG), ALL BEARINGS REPLACED DUE TO CORROSION AND DENTING, BLADE REPLACED WITH NEW BLADE, MATCHED, PAINTED AND PROPELLER TO BE ASSEMBLED IAW MM.

(CAN) PROPELLER RECEIVED FOR O/H. UPON DISMANTLING DISCOLORATION ON THE BLADE SHANKS WAS NOTED. SHANKS WERE LIGHTLY MEDIA BLASTED AND THE DAMAGE IS MORE SEVERE THAN AT FIRST INSPECTION. BLADE SHANK RADIUS IS AT 4.194 INCHES MINIMUM FOR REPAIR IS 4.187 INCHES. THESE 3 BLADES ARE UNSERVICEABLE DUE TO THIS CORROSION. (TC NR 20060928005)

(CAN) PROP WAS SLOW TO CYCLE THROUGH HIGH PITCH. PROP INSPECTED & HUB FOUND CRACKED ABOUT 6 INCHES LONG AROUND NR 1 BLADE SHANK. PROP SENT TO HOPE AERO FOR OVERHAUL.

Parts most often named Engine (3) · Seal (2) · Plunger (1) · Oil System (1)

(CAN) PILOT NOTICED OIL SEEPING FROM AROUND OIL CAP AND FILLER NECK. OIL TANK VENT WAS INSPECTED WITH NO DEFECTS FOUND. ENG COMMPRESSION WAS TAKEN AND FOUND SATISFACTORY. OIL CAP WAS FOUND TO BE A LOOSE FIT. A NEW CAP GASKET WAS INSTALLED AND CAP WAS ADJUSTED FOR A TIGHTER FIT. ENG WAS GROUND RUN AND FOUND SATISFACTORY. OIL TANK MAY HAVE BEEN FILLED TO TOP OF NECK AND WITH A POOR SEALING CAP OIL WILL SEEP FROM TANK FILLER NECK.

(CAN) THE ACFT MADE AN UNSCEDULED LANDING WHEN THE OIL PRESSURE PLUNGER BECAME JAMMED IN THE BODY OF THE OIL PRESURE RELIEF VALVE CAUSING A LOSS OF OIL PRESSURE. MX REPLACED THE PLUNGER AND THE ENGINE WAS RETURNED TO [S/N removed].

(CAN) ENGINE REMOVED DUE TO EXCESSIVE OIL CONSUMPTION. UPON REMOVING NR 7 CYLINDER INTAKE TUBE, OIL WAS NOTED. THIS INDICATES POSSIBLE IMPELLER SEAL FAILURE. ENGINE WAS REMOVED FROM [S/N removed]. (TC NR 20070727005)

Parts most often named Pump (7) · Diaphragm (1) · Shaft (1) · Drive Shaft (1)

(CAN) ENGINE DRIVEN FUEL PUMP FAILURE IN FLIGHT. LOW PRESSURE WARNING LIGHT ACTIVATED. PILOT ACTIVATED MANUAL FUEL PUMP.

(CAN) ENGINE REMOVED FOR O/H AT OWNER`S REQUEST. ENGINE IN [S/N removed] CONDITION AT TIME OF REMOVAL. ENGINE DRIVEN FUEL PUMP REMOVED AND DRIVE SHAFT SPLINES FOUND TO BE SEVERLY WORN. DRIVE PROBABLY WOULD HAVE FAILED WITHIN NEXT 50 TO 100 HRS OF OPERATION.

PILOT REPORTED FUEL PRESSURE INDICATOR DROPPED INTERMITTENTLY DURING ALL PHASES OF OPERATION. AIRCRAFT WAS RETURNED TO MAINTENANCE BASE. FUEL FOUND TO BE LEAKING FROM WOBBLE PUMP. WOBBLE PUMP DIAPHRAGM FOUND TO BE CRACKED. DIAPHRAGM REPLACED, ENGINE GROUND RUN SATISFACTORY. AIRCRAFT RETURNED TO [S/N removed].

Parts most often named Mount (6) · Tube (1) · Lock (1) · Bolt (1)

(CAN) DURING THE REMOVAL OF THE LT ENGINE IS WAS NOTICED THAT THE ENGINE MOUNT WAS CRACKED IN THE "RING" AT THE 11 O`CLOCK POSITION. THE CRACK WAS FOUND TO GO AROUND THE FULL CIRCUMFERENCE OF THE RING. ALSO TO BE NOTED THAT THIS DEFECTIVE ENGINE MOUNT ONLY HAD 174 HRS TTSO.

(CAN) VISUAL INSPECTION OF LT AND RT LOWER ENGINE MOUNT CLUSTERS SHOWS INDICATION OF CRACKS ALONG WELDS AT THE JUNCTION OF NR 37 & NR 36 TUBING WELD ASSEMBLIES AFT OF THE FIREWALL ON THE TRUSS ASSY. THIS INSPECTION WAS COMPLETED AFTER AN IDENTICAL FAILURE WAS FOUND ON ANOTHER OF OUR FLEET ACFT AND WAS CONFIRMED BY NDT MAG PARTICLE INSPECTION.

(CAN) VISUAL INSPECTION OF LT LOWER ENGINE MOUNT CLUSTER, AFT OF THE FIREWALL, SHOWED INDICATIONS OF POSSIBLE CRACKS ALONG THE WELDS IN THE JUNCTION OF 36 &37 TRUSS TUBES. THE RT LOWER ENGINE MOUNT CLUSTER WAS VISUALLY INSPECTED AND SHOWED NO SIMILAR INDICATIONS. NDT MAG PARTICLE INSPECTION WAS CARRIED OUT ON BOTH LT AND RT CLUSTERS AND BOTH WERE FOUND TO BE CRACKED IN THESE AREAS.

Parts most often named Bulkhead (5) · Plate (2) · Spinner (2)

(CAN) DURING AN ANNUAL INSPECTION A TECH FOUND CRACKS AROUND THE SPACER MOUNT BOLT HEADS ON REAR FACE OF BULKHEAD. THE PROP WAS REMOVED AND PARTIALLY DISASSEMBLED REAR BULKHEAD AND FOUND SUBSTANTIAL CRACKING UNDER CENTER REINFORCING PLATE ON FWD FACE OF REAR BULKHEAD.

CRACKS DISCOVERED NEAR OTBD FLANGE AND INSIDE HOLE FOR PROP SHAFT, SEVERAL RIVETS SHEARED. COULD HAVE BEEN A PROBLEM IF UNDETECTED.