What happened
The FAA’s narrative, in sentence case. The FAA writes it in capitals and removes private details.
Acft experienced engine failure, lost all power and made an emergency landing on highway 88, on landing, the acft ran off the highway and struck a tree. (.4) while en route to the destination airport, the airplane experienced a loss of engine power. The pilot made a forced landing on a highway and collided with a snow pole. The airplane veered off of the road and came to rest after it collided with a tree. The owner/builder stated that he had modified the drive shaft from the original 'v' belt drive to a dual 'serpentine' belt/pulley system. He further stated that in order to install the new belt/pulley system, he had to weld a retaining pin in the center of the original drive shaft. The propeller governor pulley was found at the bottom of the engine compartment and the shaft was found to have separated at the center point. The drive shaft exhibited a bluing and discoloration at the center where the owner had welded it on the pin. It was noted that the original manufacturer of the propeller governor drive shaft had placed a heat treat stamp on the shaft. (-23) August 5, 1998 10:20 am, experimental amateur-built (P-51 replica N151MT) had a forced landing on highway 88, 20 miles east of Jackson, CA. No injuries reported by pilot (only sole on board) or ground personnel. Aircraft was substantially damaged. Propeller governor drive shaft had failed in an area that had been modified by the amateur builders. The drive shaft fell out of the engine, and oil pressure was lost.
As the FAA filed it
ACFT EXPERIENCED ENGINE FAILURE, LOST ALL POWER AND MADE AN EMERGENCY LANDING ON HIGHWAY 88, ON LANDING, THE ACFT RAN OFF THE HIGHWAY AND STRUCK A TREE. (.4) WHILE EN ROUTE TO THE DESTINATION AIRPORT, THE AIRPLANE EXPERIENCED A LOSS OF ENGINE POWER. THE PILOT MADE A FORCED LANDING ON A HIGHWAY AND COLLIDED WITH A SNOW POLE. THE AIRPLANE VEERED OFF OF THE ROAD AND CAME TO REST AFTER IT COLLIDED WITH A TREE. THE OWNER/BUILDER STATED THAT HE HAD MODIFIED THE DRIVE SHAFT FROM THE ORIGINAL 'V' BELT DRIVE TO A DUAL 'SERPENTINE' BELT/PULLEY SYSTEM. HE FURTHER STATED THAT IN ORDER TO INSTALL THE NEW BELT/PULLEY SYSTEM, HE HAD TO WELD A RETAINING PIN IN THE CENTER OF THE ORIGINAL DRIVE SHAFT. THE PROPELLER GOVERNOR PULLEY WAS FOUND AT THE BOTTOM OF THE ENGINE COMPARTMENT AND THE SHAFT WAS FOUND TO HAVE SEPARATED AT THE CENTER POINT. THE DRIVE SHAFT EXHIBITED A BLUING AND DISCOLORATION AT THE CENTER WHERE THE OWNER HAD WELDED IT ON THE PIN. IT WAS NOTED THAT THE ORIGINAL MANUFACTURER OF THE PROPELLER GOVERNOR DRIVE SHAFT HAD PLACED A HEAT TREAT STAMP ON THE SHAFT. (-23) AUGUST 5, 1998 10:20 AM, EXPERIMENTAL AMATEUR-BUILT (P-51 REPLICA N151MT) HAD A FORCED LANDING ON HIGHWAY 88, 20 MILES EAST OF JACKSON, CA. NO INJURIES REPORTED BY PILOT (ONLY SOLE ON BOARD) OR GROUND PERSONNEL. AIRCRAFT WAS SUBSTANTIALLY DAMAGED. PROPELLER GOVERNOR DRIVE SHAFT HAD FAILED IN AN AREA THAT HAD BEEN MODIFIED BY THE AMATEUR BUILDERS. THE DRIVE SHAFT FELL OUT OF THE ENGINE, AND OIL PRESSURE WAS LOST.
NTSB investigation
The NTSB’s investigation of this event, with its probable cause and findings. Matched to this report by N-number and date.