NTSB Factual Report

On March 25, 2011, at 1738 eastern daylight time, a Holst experimental amateur-built VP-1 Volksplane, N770VP, registered to a private owner experienced a partial loss of engine power on initial takeoff climb from Tom B. Field (CZL), Calhoun, Georgia. The pilot made a forced landing to an open field and the airplane sustained structural damage to the fuselage. The personal flight was operated under the provisions of 14 Code of Federal Regulations Part 91. No flight plan was filed and visual meteorological conditions prevailed. The commercial pilot reported minor injuries. The flight originated from CZL at 1730.

The pilot stated this was the maiden flight since he had built the airplane. No anomalies were noted during the preflight inspection. The airplane contained 8 gallons of fuel and no water was present in the fuel tank or gascolator. The pilot conducted the engine start with the checklist, and two engine run ups, and no anomalies were noted. The carburetor heat was checked and a drop in engine rpm was observed. The pilot taxied into position and cylinder head temperature was in the yellow arc. He initiated the takeoff and was on initial takeoff climb at 200 feet above ground level when the engine started "surging" from a high power setting to a low power setting. The cylinder head temperature was in the red arc. The pilot turned the airplane to the left looking for a forced landing area. He pulled the power back and initiated a forced landing to an open field. The airplane landed hard, resulting in structural damage to the airframe.

A review of the aircraft logbooks revealed the last condition inspection was conducted on December 28, 2010. No Hobbs meter was installed on the airplane and it had been operated about 8 minutes since the condition inspection. The airplane was equipped with a Volkswagen 218OCC, 75 horsepower carburetor engine.

Examination of the airplane revealed the propeller assembly remained attached to the propeller crankshaft propeller flange. One wood propeller blade was separated about 10 inches outboard of the propeller hub. The remaining propeller blade remained attached to the propeller hub. The engine cowling was crushed and separated and the engine assembly was separated from the engine mounts and the firewall.

The forward cabin area was crushed aft into the pilot seat. The instrument panel was destroyed. The throttle and carburetor heat control was partially destroyed, although still attached to a separated section of the instrument panel. The throttle was in idle position and the carburetor heat control was off. A fuel selector valve was not installed. The fuel tank was ruptured and about 8 ounces of fuel was present in the fuel tank and the gascolator was not contaminated.

Continuity of the flight controls was confirmed from the control stick aft to all flight control surfaces. The forward half of the cabin seat was deformed. The seatbelt and shoulder harness were in use at the time of the accident.

The right wing remained attached to the wing root and was damage. The remaining section of the leading edge was not damaged. Both right wing struts remained attached to the wing. The aft wing strut was attached to the fuselage aft bulkhead and the forward wing strut was attached to the fuselage. The right aileron was not damaged and remained attached at all hinge points. The right main landing gear was separated from the wing.

The empennage was intact with the elevators, vertical stabilizer, and rudder. The fuselage was destroyed from pilot seat extending aft 6 feet.

The left wing separated at the wing root. The leading edge of the wing was perpendicular with the ground. Both wing struts remained attached to the wing but were separated from the fuselage. The left aileron was damaged and half of the aileron was separated from the wing. Three feet of the outboard wing was separated and crushed. The left main landing gear separated from the wing.

Continuity of the engine internal components was confirmed. The engine had two sources for ignition, one magneto and one distributer, along with two spark plugs for each cylinder. Cylinder compression was confirmed along with ignition. Both engine valve covers were missing from the engine, however valve train continuity was confirmed. Spark plugs were removed and inspected and exhibited normal wear.

The pilot stated to the Federal Aviation Administration (FAA) inspector that he followed the carburetor adjustment procedure for the main carburetor jet adjustment in accordance with the Zenith Carburetor adjustment procedure manual. He confirmed that during the adjustment he set the main jet adjustment to the lean point of the setting. After running up the engine the main jet was subsequently re-adjusted further to a leaner point from the initial adjustment.

NTSB Probable Cause

A partial loss of engine power during initial climb due to an over-lean carburetor setting. Contributing to the accident was the pilot's improper adjustment of the engine's carburetor during construction.