NTSB Identification: CHI87DEC05.
The docket is stored on NTSB microfiche number 39104.
Accident occurred Friday, September 25, 1987 in FRASER, MI
Probable Cause Approval Date: 12/10/1990
Aircraft: WILLI/BENSEN B-8M, registration: N2469
Injuries: 1 Uninjured.

AS THE STUDENT PILOT WAS TAKING OFF IN HIS EXPERIMENTAL HOME BUILT GYROPLANE, THE ENGINE LOST POWER, SHORTLY AFTER LIFT-OFF. SUBSEQUENTLY, THE GYROPLANE WAS DAMAGED DURING AN EMERGENCY LANDING. AN EXAM OF THE FUEL SYSTEM REVEALED THAT TANK SEALER HAD DETERIORATED ON THE INSIDE OF THE SEAT TANK & HAD DROPPED IN THE FUEL. SUBSEQUENTLY, A CHECK VALVE FOR A RUBBER HAND BULB (USED TO PRIME THE FUEL PUMPS) HAD BECOME STUCK. THIS RESULTED IN BLOCKAGE OF FUEL TO THE ENGINE.

The National Transportation Safety Board determines the probable cause(s) of this accident to be:

DETERIORATION OF THE INTERNAL SURFACE OF THE FUEL TANK WHICH LED TO BLOCKAGE OF THE FUEL FLOW AND SUBSEQUENT FUEL STARVATION OF THE ENGINE.

Index for Sep1987 | Index of months