NTSB Identification: LAX90LA241.
The docket is stored on NTSB microfiche number 43474.
Accident occurred Monday, July 02, 1990 in FULLERTON, CA
Probable Cause Approval Date: 11/23/1992
Aircraft: CESSNA 152, registration: N48418
Injuries: 1 Uninjured.

NTSB investigators may not have traveled in support of this investigation and used data provided by various sources to prepare this aircraft accident report.

THE STUDENT SAID THAT WHILE FLYING TOWARD THE AIRPORT, THE ENGINE POWER OUTPUT SUDDENLY DROPPED AND VARIED BETWEEN 900 AND 1,400 RPM. THE POWER WAS INSUFFICIENT TO MAINTAIN FLIGHT AND THE STUDENT SAID HE REALIZED HE COULD NOT MAKE THE AIRPORT. HE SAW A LEVEL DIRT ROAD AT A CONSTRUCTION SITE AND MADE A FORCED LANDING. THE AIRCRAFT CONTACTED GROUND OBSTACLES DURING THE LANDING ROLL AND NOSED OVER. TEARDOWN OF THE ENGINE REVEALED THAT ALL VALVES AND VALVE SEATS WERE WARPED, WITH EVIDENCE OF EXHAUST GASSES ENTERING THE INTAKE PORTS. THE ENGINE WAS REPORTEDLY AT TBO.

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

THE WARPED CONDITION OF THE ENGINE VALVES AND VALVE SEATS DUE TO EXCESSIVE AND REPEATED THERMAL SHOCK CYCLES.

Index for Jul1990 | Index of months