On November 11, 1989, a Beech 95 (registration N17AT) operated by B & H Aviation was involved in an aviation accident near Floydada, TX. Investigators recorded the probable cause as: FAILURE OF THE PROPELLER ATTACHMENT BOLTS DUE TO FATIGUE IN FOUR OF THE BOLTS AND OVERLOAD IN ANOTHER. A CONTRIBUTING FACTOR WAS THE LOSS OF ELECTRICAL POWER AND THE DETERIORATED AIRPLANE CONTROL/PREFORMANCE. This summary draws on records from the U.S. National Transportation Safety Board (NTSB) historical archive.
During cruise, the right propeller spinner detached, followed by the propeller separating and striking the nose. The pilot performed a wheels-up landing at the destination after losing electrical power and control.
Incident Overview
A twin-engine airplane experienced a propeller separation while at cruise. The right propeller spinner fell off first. Three to four minutes later, the right propeller itself detached, cutting into the nose of the aircraft. The airplane lost electrical power and control deteriorated. The pilot elected to land wheels-up at the destination airport.
Sequence of Events
The right propeller spinner separated from the aircraft during cruise. Shortly thereafter, the right propeller detached and struck the nose. The airplane became uncontrollable without electrical power, prompting the pilot to execute a gear-up landing on the runway at the destination.
Post-Accident Examination
Investigators recovered five propeller attachment bolts from the engine crankshaft flange. The right propeller and the center of the starter ring were not found. Laboratory visual inspection revealed that four of the five bolts failed due to fatigue, while the fifth bolt failed due to overload. No other components were examined.