Errant fuel selector valve brings down Ercoupe

This January 2010 accident report is provided by the National Transportation Safety Board. Published as an educational tool, it is intended to help pilots learn from the misfortunes of others.

Aircraft: Ercoupe 415-D. Injuries: None. Location: Napa, Calif. Aircraft damage: Substantial.

What reportedly happened: The pilot, 23, who had logged 410 hours, said the takeoff was normal but when the airplane was at an altitude of approximately 100 feet AGL, the engine began to lose power. The engine surged twice, then quit. He landed in an open field off the end of the runway. During the landing the nosewheel sank into the soft ground, collapsed, and the airplane nosed into the ground. The pilot reported that both wing fuel tanks were full and the engine run up was normal.

During the post-accident examination, fuel was found in both wing tanks and the main fuel valve was observed rotated to the 2 o’clock position. The valve was a two position valve, “off” when positioned to 9 o’clock, and “on” when positioned to 12 o’clock. Investigators observed that the valve had no positive stops and could be rotated past the 9 o’clock or 12 o’clock positions. The valve was located on the far left bottom side of the instrument panel, about knee level, which was not the standard location for the valve.

When the engine was run up to 2,500 rpm, and the pilot in the left seat moved his left knee to the left, it would push on the fuel valve, rotating it to the 2 o’clock position. With the fuel valve at the 2 o’clock position, fuel flow to the carburetor was reduced to a trickle, and the engine slowly lost power.

The airplane owner stated that he purchased the airplane with the fuel valve located in its current position. The Ercoupe Approved Airplane Flight Manual states that the main fuel valve should be located halfway between the brake handle (just below the throttle handle) and the left yoke control wheel directly behind the instrument panel.

Probable cause: A loss of engine power due to fuel starvation as a result of the unintentional movement of the fuel selector valve beyond its stops during takeoff initial climb resulting in restricted fuel flow.

For more information: NTSB Identification: WPR10LA111.

Leave a Reply

Your email address will not be published. Required fields are marked *