Accident Sequence
On departure, the pilot reported that the airplane's fuel tanks were topped off with 72 gallons of 100LL aviation fuel. During the takeoff roll, when airspeed reached 85 miles per hour (mph), the pilot rotated and the aircraft began to climb. As the airspeed increased to 95 mph, the airplane suddenly yawed to the right and the airspeed decreased. The pilot stated that it "felt like my right engine stopped working." Within 3 to 4 seconds, the airplane was over a row of hangars. The pilot lowered the nose in an attempt to gain airspeed, but there was insufficient altitude to clear the hangars. The airplane subsequently collided with one hangar and then impacted two parked aircraft.
Post-Accident Examination
Examination of the right engine revealed that the mixture control cable was disengaged from the carburetor mixture control arm. Additionally, the cotter pin used to secure the tension nut on the mixture cable was not installed. The mixture control swivel, stud, and a segment of the mixture control cable were examined at the NTSB's Materials Laboratory in Washington, DC. According to a Safety Board metallurgist, examination of some components indicated wear damage. However, the mixture control cable did not exhibit any longitudinal gouge marks or wear damage that would be consistent with it being separated during the accident sequence.
The engine was subsequently test-run and operated at various power settings up to 1,500 RPM. It ran continuously and without hesitation for approximately 10 minutes. The propeller was actuated and operated normally. Both magnetos were checked and no anomalies were noted. The engine-driven fuel pump produced suction and exhaust, and oil was noted draining from the forward crankshaft area.
Pilot Experience and Weight and Balance
The pilot reported a total of 377 flight hours, of which 41 hours were in twin-engine aircraft. He also reported a total of 10 hours in the same make and model airplane. A weight and balance computation was made using the airplane's original factory weight and balance. Based on the calculations, the airplane was within weight and balance limits.