NTSB Identification: MIA91FA095.
The docket is stored on NTSB microfiche number 43367.
Accident occurred Saturday, March 09, 1991 in KEY WEST, FL
Probable Cause Approval Date: 02/08/1993
Aircraft: BEECH 35-C33A, registration: N4828J
Injuries: 3 Fatal.
NTSB investigators either traveled in support of this investigation or conducted a significant amount of investigative work without any travel, and used data obtained from various sources to prepare this aircraft accident report.
WITNESSES RPTD THEY HEARD PROPELLER OVERSPEED FOLLOWED BY ENGINE PWR BEING REDUCED TO IDLE AS IF PILOT PULLED THROTTLE CLOSED. ACFT THEN BANKED TO LEFT AND ENTERED SPIN TO THE LEFT CRASHING INTO A PARKING LOT. POST CRASH EXAMINATION OF THE ENGINE, ACFT STRUCTURE, AND FLIGHT CONTROLS REVEALED NO EVIDENCE OF PRECRASH FAILURE OR MALFUNCTION. EXAMINATION OF THE PROPELLER REVEALED THE NUMBER TWO BLADE PITCH CHANGE ACTUATING PIN HAD FAILED DUE TO FATIGUE. THE PIN HAD BEEN INSTALLED AT OVERHAUL, 600 FLT HOURS BEFORE THE ACCIDENT, BY FOLLOWING MCCAULEY SERVICE BULLETIN 99 WHICH IS NOT APPLICABLE TO THIS MODEL PROPELLER. THE PIN WAS INSTALLED BY USING A SHORT THREADED PIN, A THIN SPACER, AND A BLIND HOLE IN THE FERRULE. THIS COMBINATION ALLOWED THE PIN TO BOTTOM OUT IN THE HOLE THUS NOT TORQUING PROPERLY AND THUS CRACKING DUE TO APPLIED LOADS.
The National Transportation Safety Board determines the probable cause(s) of this accident to be: THE PILOT-IN-COMMAND'S FAILURE TO MAINTAIN AIRSPEED, WHILE RETURNING FOR AN EMERGENCY LANDING FOLLOWING PROPELLER FAILURE, RESULTING IN THE AIRCRAFT STALLING AND ENTERING A SPIN.
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