Accident Summary
An airplane experienced a loss of engine power during flight, leading to a forced landing that resulted in substantial damage to the aircraft. The forced landing occurred in a field after the pilot was unable to maintain engine operation.
Pilot's Report
The pilot reported that during cruise flight at 8,000 feet msl, he observed sluggish and erratic trends on the left fuel gauge. During descent from 8,000 feet, the engine began to run rough. The pilot immediately switched the fuel selector to the right fuel tank and activated the low boost pump. He reported that the engine then spooled down. He established a 110-knot glide attitude. He then set the electric fuel pump to high boost and moved the mixture control to full rich. The engine restarted briefly, then stopped. The pilot executed a forced landing to a field. He noted that he did not have sufficient visual references with which to accurately flare, so the airplane impacted the ground at approximately 85 knots indicated.
Aircraft Examination
Inspection of the airplane revealed that the right fuel tank contained about 25 gallons of fuel. The left fuel tank was de-fueled, and 3 gallons and 8 ounces of fuel were removed from it. The aircraft placard states that the unusable fuel is 3 gallons.
Pilot Operating Handbook Information
The Pilot Operating Handbook provides specific guidance regarding the use of the auxiliary fuel pump switch. It states: "The HI position is used for priming the engine during cold starts and also to provide an alternate source of fuel pressure in the event the engine-driven fuel pump fails. HI boost must not be used during flight unless the engine-driven fuel pump has failed. The increased pressure of the HI boost will over-drive the fuel control unit producing abnormally high fuel flows which, in turn, will cause engine roughness. In some cases, engine combustion may cease."