Accident Overview
An experimental airplane collided with grapevines and support posts during a forced landing following a loss of engine power while on downwind for the runway. The pilot performed prelanding checks on downwind, and upon switching on the second fuel pump, the engine lost power.
Sequence of Events
The pilot switched the fuel pump to the original position and selected the other fuel tank. Neither action caused the engine to regain power. The pilot attempted to lower the electrically powered flaps to prepare for an emergency landing on the runway, but the flaps failed to deploy. The airplane carried an excess of 30 to 40 knots while flying 10 to 20 feet above the runway. The pilot determined that he would easily overrun the 2,480-foot-long runway and impact structures at the end if he did not divert the airplane's path. He pulled up and turned left 180 degrees to dissipate the extra energy and landed along the vine rows of the neighboring vineyard.
Post-Accident Examination
First responders reported that there appeared to be no fuel in the airplane's fuel tanks nor evidence of a post-accident fuel spill or leak from the airplane. The pilot said that the airplane's electrical system powers the engine's electronic ignition, propeller pitch control, and flaps. Examination of the electrical system revealed that the "Master Power Switch" being used was an automotive keyed single pole single throw switch, and that the back was loose and coming apart, making the internal electrical contacts intermittent. This switch ties together power from the batteries and the alternator. Failure of this switch could result in the loss of ignition power to the engine.