415Ercoupe · Aircoupe

Parts most often named Spar (7) · Spar Cap (7) · Rib (1)

INSP OF WING CTR SECTION IAW AD 2002-26-02 INTER-GRANULAR CORROSION IN EXFOLIATION STAGE WAS DISCOVERED ON THE BOTTOM MAIN SPAR CAP, EXTREME REAR OTBD SECTIONS WHERE IT WAS MILLED TO ACCOMMODATE THE MLG TRUNNION AND JUST INBD. ALSO THE LT AND RT (WING WALK) INBD T/E RIBS WERE CORRODING AWAY AND CORROSION WAS FOUND ON THE SURFACE ON VARIOUS LOCATIONS ON THE CTR SECTION.

DURING ACCOMPLISHMENT OF SB NR 32, A 0.625 INCH LONG, SPANWISE CRACK WAS NOTED ON THE RT UPPER SPAR CAP IN THE MAIN SPAR CENTER SECTION APPROX 0.250 INCH IB OF THE CENTER SECTION OB END. PROBABLE CAUSE IS UNKNOWN. (K)

(CAN) DURING INSPECTION TO COMPLY WITH AD 2003-21-01 SEVERE CORROSION FOUND ON FORWARD END OF RIB, AFT OF REAR SPAR, IN THE RT CENTER SECTION, BETWEEN THE FUSELAGE AND WING. THE CORROSION WAS NOT READILY NOTICEABLE UNTIL INSTALLATION OF INSPECTION PANELS SK 80-2 IAW SB 31 REV 1. THIS ALLOWED ACCESS TO THIS AREA WHICH OTHERWISE IS HARD TO SEE, EVEN THOUGH THE WINGS WERE REMOVED TO COMPLY WITH THE INSPECTION REQUIREMENTS OF 2003-21-01.

Parts most often named Rib (6)

INTERGRANUAL CORROSION FOUND ON LT CENTER SECTION RIB WS 36. FOUND DURING INSPECTION AND COMPLIANCE OF AD 2002-26-02, NEEDS REPAIR.

COMPLIANCE WITH AD 2002-26-02 DETECT AND CORRECT CORROSION IN WING CENTER SECTION. FOUND 5 RIVETS CORRODED OFF THE LOWER CENTER RIB ON THE RT WING WALKWAY BOX.

AD 2002-26-02 ADMENDMENT 39-12987, MFG [S/N removed] BULLETIN NR 31. METHOD 1, INSPECTION HOLES IN WING CENTER SECTION. INSPECTED FRONT AND REAR SPARS...NO EVIDENCE OF CORROSION. DISCOVERED CORRODED RIB, RIGHT SIDE TRAILING EDGE WING WALK BOX. REMOVED AND REPLACED RIB WITH NEW MANUFACTURED. CLEANED LIGHT CORROSION FROM TRAILING EDGE WING WALK OUTER SKINS, TREATED AREA WITH ZINC CHROMATE. TREATED WING CENTER SECTION WITH CORROSION INHIBITOR.

Parts most often named Valve (2) · Exhaust Valve (2) · Cylinder (1) · Rocker Arm (1)

CYLINDER AND ROD FAILURE RESULTED IN CASE FAILURE CAUSING CYLINDER TO COME OF ENGINE. CAUSE UNKNOWN. NR 4 PISTON (AE-C530348) FAILURE. (WP09200502317). (K)

THE FACE OF THE NR 2 CYL EXHAUST VALVE SEPARATED FROM THE STEM OF THE VALVE. SUBSEQUENT DAMAGE TO THE POSTON AND CYLINDER WAS SUBSTANTIAL. THIS FAILURE OCCURRED WHILE IN CRUISE FLIGHT.

NR 2 CYLINDER HAD INTAKE AND EXHAUST ROCKER ARM ASSEMBLIES SWITCHED. NR 2 EXHAUST VALVE MIGHT HAVE STUCK DUE TO NO LUBRICATION OR COOLING FROM THE DRILLED PASSAGEWAY BECAUSE THE EXHAUST ROCKER ARM WAS IN THE INTAKE VALVE POSITION. INTAKE ROCKER FAILED.

Parts most often named Skin (3)

INSPECTION OF WING CENTER SECTION PER AD 02-26-02 FOUND LIGHT CORROSION ON LOWER SKINS, MODERATE CORROSION ON 3 STIFFENERS. REPLACED STIFFENERS, CLEANED AND TREATED SKIN. AIRCRAFT WAS OUTSIDE WITHOUT COVER FOR AT LEAST 30 YEARS.

Parts most often named Stiffener (1) · Bracket (1) · Reinforcement (1)

REMOVED AND REPLACED (2) ANGLE BRACKETS IN LT WING WALKWAY THAT WERE ATTACHED TO THE RIB. THESE WERE FOUND CORRODED DURING THE INSTALLATION OF INSPECTION PANELS BEING INSTALLED TO COMPLY WITH AD 02-26-02. IT APPEARED WATER HAD BECOME TRAPPED INSIDE TRAILING EDGE OF WALKBOX AND CORROSION HAD SET IN. THE RIB WAS NOT AFFECTED. AIRCRAFT NEEDS SMALL DRAIN HOLE IN THIS AREA FOR DRAINAGE.

SEVERE CORROSION FOUND DURING ANNUAL. THIS OCCURED SINCE LAST ANNUAL JULY, 1996. CORROSION COULD NOT BE OBSERVED THROUGH INSPECTION HOLES IN WING. CAN ONLY BE SEEN WITH AILERON FULLY IN UP POSITION AND LOOKING UPWARD FROM THE GROUND. IT IS NOT READILY SEEN LOOKING DOWN THROUGH THE GAP BETWEEN WING AND AILERON. SUBMITTER RECOMMENDED OTHER OWNERS INSPECT BEFORE NEXT FLIGHT AND 3 TO 4 TIMES A YEAR THEREAFTER.

Parts most often named Coil (2) · Gear (1)

(CAN) AIRCRAFT HARD TO START WHEN ENGINE IS HOT. CHECKED MAGNETO TO ENGINE TIMING. COULD NOT GET RT MAGNETO ([S/N removed]) POINTS TO OPEN OR CLOSE. REMOVED MAGNETO FROM ENGINE AND FOUND GROUND ON COIL MISSING SCREW. COIL FOUND TO BE CRACKED AND OPAQUE IN COLOR INDICATING AD 94-01-03R2 AND MSB 644 HAD NOT BEEN ACCOMPLISHED. TECHNICAL RECORDS INDICATE ENGINE JUST HAD FIELD OVERHAUL. TIME ON ENGINE IS ONLY 14.3 HOURS.

Parts most often named Rib (1) · Skin (1)

Parts most often named Support (1) · Fitting (1)

THE SUPPORT ASSY THAT SUPPORTS THE BATTERY BOX AND BATTERY IS SEVERLY CORRODED. NO PART NUMBER FOUND IN MFG PARTS CATALOG.

Parts most often named Carburetor (1) · Throttle Cable (1)

AIRCRAFT WAS OUTSIDE FOR 3 YEARS NOT RUNNING. UPON INVESTIGATION, NOTED EXCESSIVE WATER IN CARBURETOR. REMOVED CARBURETOR FOR REPAIR.

Parts most often named Bushing (1) · Hub Assy (1)

HUB CRACKED ALONG KEYWAY AND PROGRESSED UP PROP FLANGE TO WITHIN .50 INCH OF BOLT HOLE. ASSUME THIS ALLOWED THE HUB TO BECOME LOOSE AND LET NUT, PN 21202, LOOSEN AND WEAR ON SAFETY PIN, PN AN 392-11, CAUSING IT TO BREAK AND ALLOW NUT TO UNSCREW AND LET PROP AND HUB ASSY TO DEPART AIRPLANE.

DURING ANNUAL INSPECTION, FOUND FUEL HOSE FABRICATED AS BUSHINGS AND INSTALLED IN PLACE OF NR A437 STEEL PROPELLER DOWEL BUSHINGS.