Scottish Aviation SERIES 100 MDL 101 N101MY accident near Chandler, Arizona

Probable cause

A loss of engine power during cruise flight for reasons that could not be determined because postaccident examination did not reveal any anomalies that would have precluded normal operation.

NTSB analysis

The pilot reported that the engine surged and sustained a partial loss of engine power during a local night flight. He attempted to restore engine power, but was unsuccessful and made a forced landing to an open field where the airplane impacted a ditch, collapsing the landing gear and bending the firewall during the landing roll. The pilot said that the entire flight was performed with the fuel selector on the “BOTH” position and that when the engine first began to surge, the fuel gauges registered a quarter of capacity in each tank.

The fuel system consisted of inner and outer interconnected tanks in each wing, which supplied fuel through a non-return valve to a fuel selector, a filter, and a booster pump grouped together near the front left seat, then through the engine-driven pump to the injector unit. Unusable fuel in each wing is 0.5 gallons. Airplane recovery personnel said that no fuel was found in the left wing tanks and about 8 gallons of fuel were found in the right wing tanks, although the gear collapse may have allowed fuel to migrate from the high wing to the low wing. The airplane was examined and no fuel system discrepancies were found. The engine was test run in the airframe and it started and ran normally.

Text from the NTSB. Open the NTSB docket for WPR11LA246 for the full record.