NTSB Identification: DEN04LA107.
The docket is stored in the Docket Management System (DMS). Please contact Records Management Division
Accident occurred Tuesday, July 20, 2004 in Douglas, WY
Probable Cause Approval Date: 07/07/2005
Aircraft: Cessna P210N, registration: N7736K
Injuries: 4 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.

According to the pilot, while in cruise flight at 22,000 feet msl, the engine "quit." The pilot stated that the propeller continued to "windmill," and at that time he noted approximately 50 gallons of fuel remaining. The pilot's attempts to restart the engine were unsuccessful. He declared an emergency and was diverted to a nearby airport. On final approach to runway 28, the airplane's left main landing gear struck a fence post. The airplane landed approximately 200 feet short of the runway threshold and its left main landing gear collapsed. The airplane veered left of the runway centerline and came to a stop in the grass. The impact buckled the left wing tip and left horizontal stabilizer. An examination of the engine revealed a 7/8-inch by 3/8-inch hole in the top of the crankcase, just forward of the number 1 cylinder. Further examination revealed the engine crankshaft was fractured at the number 2 rod journal. The crankshaft exhibited thermal discoloration and impact marks at the number 2, 3, 4, and 5 rod journals. Rotational scoring and thermal discoloration was observed on the crankshaft's number 2 main bearing. The number 2 bearing was fragmented and fretting was observed on the crankcase halves at the number 2 bearing through bolts. The engine maintenance records indicated on November 17, 2003, at 2,845.0 hours, during the airplane's most recent 100-hour inspection, the number 2 cylinder was replaced. At the time of the accident, the total time was 3,083.0 hours.

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

the failure of the engine's crankshaft due to the rotation of the engine's number two bearing, which resulted in the oil starvation of the crankshaft's number 2 main journal. Contributing factors include the engine's improper maintenance, and the in-flight collision with a fence post during a forced landing.

Full narrative available

Index for Jul2004 | Index of months