What was found
OWNER REPORTED 5 OF 6 AN 6-60 PROPELLER BOLTS FAILED IN-FLIGHT. BOLTS SENT TO MFG, FOUND IN SPEC REASON FOR FAILURE DUE TO BOLTS BEING TOO LONG PREVENTING PROPER CLAMP-UP OF CRUSHPLATE AND SPINNER BULKHEAD TO CAMSHAFT FLANGE EXTENSION. FAILED BOLTS SHOWED 4 TO 5 THREADS PROTRUDING FROM NUTS WITH 2 WASHERS UNDER EACH NUT. SUBMITTER STATED TO CAUTION MECHANICS NOT TO ALLOW MORE THAN 2 THREADS TO SHOW BEYOND THE NUT. (X)