N2332HErcoupe 415-D · 1946

On January 14, 2010, at 1441 Pacific standard time, a Ercoupe 415-D, N2332H, experienced a loss of engine power after takeoff and landed in a field off the end of runway 36R at Napa County Airport, Napa, California. The commercial pilot operated the airplane under the provisions of Title 14 Code of Federal Regulations, Part 91. The pilot was uninjured and the airplane was substantially damaged. Visual meteorological conditions prevailed, and a flight plan had not been filed.

The pilot reported to the Safety Board investigator that both wing fuel tanks were full and the engine run up was normal. Almost immediately after takeoff, at 100 feet above ground level (agl), the engine began to lose power, surged two times, and then lost all power. The pilot landed in an open field off the end of the runway. During the landing the nose wheel sank into the soft ground and collapsed.

The pilot, age 23, held a commercial pilot certificate with ratings for airplane single engine land, airplane multi-engine land, and instrument airplane, issued April 30, 2008. He held a third-class medical certificate issued on May 16, 2008, with no limitations or waivers. The pilot reported that he had 410 hours of total time, and 13 hours in the Ercoupe. His most recent flight review was dated April 30, 2008.

The two seat, low wing, fixed-gear airplane, serial number (S/N) 2957, was manufactured in 1946. It was powered by a Teledyne Continental Motors (TCM) O-200, 100-hp engine, and equipped with a McCauley fixed pitch propeller. Examination of the aircraft maintenance logbooks showed that the total airframe time was 1,608 hours, and that an overhauled O-200 TCM engine had been installed on August 1, 2009, per Supplemental Type Certificate (STC) SA2628WE requirements, with zero time on the engine. The STC specifies an electric fuel pump be installed, however, the airplane had retained the standard engine driven mechanical fuel pump installation. A new tachometer was installed with zero time indicated, and the hobbs meter indicated 1,608.83. The fuel selector valve was located on the bottom far left side of the instrument panel, about 2 inches from the left side of the interior of the cockpit fuselage. 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.

The fuel system consists of a nine gallon tank in each wing and a six gallon fuselage tank. The engine driven fuel pump moves gasoline from the wing tanks to the six gallon fuselage tank. Excess fuel drains from the fuselage tank overflow back to the wing tanks. Fuel is gravity fed from the fuselage tank to the engine, through the main fuel valve. The main fuel valve is a two position valve, on and off.

The airplane was located about a 1/4 mile north of the departure end of runway 36 right, in a grass field, positioned nose down into the ground, with the tail oriented at a 30-degree up angle. The nose wheel had collapsed back into the underside of the airplane. Photographs of the cockpit show the main fuel valve in the 2 o’clock position. The fuel valve plate was labeled “fuel on” at the 12 o’clock position, and “fuel off” at the 9 o’clock position. The airplane was removed and taken to a facility in Pleasant Grove, California, for further examination.

On February 3, 2010, a Safety Board investigator and a technical representative from Teledyne Continental Motors examined the airplane. A visual examination revealed that the fuselage fuel tank (header tank) fuel indicator was at the bottom of the sight gauge. The tank contained about an inch of liquid, and the indicator wiggled when the airplane was shaken. The intake manifold fractured and separated above the carburetor mounting pad. The carburetor had blue staining around the carburetor bowl gasket and the inlet filter. The throttle, mixture, and carburetor heat controls moved freely from stop to stop. The carburetor accelerator pump squirted fluid with movement of the throttle.

Investigators drained a blue fluid that smelled like aviation fuel from the gascolator, right wing sump, and left wing sump; additionally, the carburetor was reattached to the engine with a replacement manifold.

The main fuel valve was located on the bottom left side of the instrument panel, the valve was positioned to the 4 o’clock position. On the first attempt after some cranking, the engine started and ran up to 1,200-1,300 rpm. The engine shut down on its own after about 1 minute. Investigators added 2 gallons of fuel to the header tank. The second attempt to start the engine had the same results.

Investigators removed the fuel line from the shutoff valve to the carburetor. A limited amount of fuel flowed (trickled) through the line. Movement of the shutoff valve to the 12 o’clock position resulted in a steady stream of fuel. Either side of 12 o’clock resulted in restricted fuel flow (at the 9-10 o’clock and the 2-4 o’clock position) down to a dribble. It was noted that the valve had no positive stops in either the ‘off’ position or the ‘on’ position.

Investigators performed another engine run with the shutoff valve in the 12 o’clock position. The engine was run up to 1,800 rpm and a magneto check was performed, with corresponding drops of 75 rpm for the left and right magneto. It was then run up to 2,500 rpm without difficulty; the rpm stabilized, and then followed throttle movement as investigators varied the rpm between 1,800-2,500. While the engine was operating at 2,500 rpm, the operator moved his left knee to the left, which moved the fuel shutoff lever to the 2 o’clock position. The engine ran about 1 minute and then the rpm dropped to 1,700-1,800. The engine sputtered and backfired, and stayed at 1,700-1,800 for 15-20 seconds. The operator reduced the throttle to idle, and the engine smoothed out; shut down was unremarkable.