NTSB Identification: SEA05LA110.
The docket is stored in the Docket Management System (DMS). Please contact Records Management Division
Accident occurred Monday, May 30, 2005 in Tacoma, WA
Probable Cause Approval Date: 10/27/2005
Aircraft: Beech A-36, registration: N9017V
Injuries: 2 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.

After flying in the local area for about 20 minutes, the pilot entered the VFR traffic pattern, and after turning on base leg the aircraft's engine suddenly lost all power. He was therefore forced to execute a power-off landing in an open field, where the aircraft's nose gear encountered some soft terrain and collapsed. A post-accident inspection determined that there was sufficient uncontaminated 100LL fuel on board. During a series of test runs, the engine ran extremely rough at rpm's below 1,500, and it quit a number of times during the run. The engine smoothed out some when the fuel boost pump was turned on to the low position, and smoothed out even more when the pump was turned to the high position. The un-metered fuel pressure was measured, and although it was lower than the specification directed, it was not low enough to account for the very rough running engine. At the end of the series of test runs, the spark plugs were removed, and their white ashy color confirmed that the engine was running extremely lean. Further flow tests and inspections were performed on the fuel system components after they were removed from the aircraft, but the results of these tests did not reveal any anomalies that would be expected to cause the engine to run rough or quit while on a reduced power approach. In addition, the fuel pump was tested to ensure that there was no air leaking past the shaft seal, and the results of that test was negative. At the completion of the testing/inspection process, it could not be clearly determined what was causing the engine's fuel system to run so lean.

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

The malfunction of the fuel injection control system, for undetermined reasons, while the aircraft was on base leg for a full-stop landing. Factors include soft terrain in the area where the pilot found it necessary to perform a forced landing.

Full narrative available

Index for May2005 | Index of months