Aircraft: Christian Eagle II. Injuries: 2 Fatal. Location: Seward, Neb. Aircraft damage: Substantial.
What reportedly happened: The flight instructor, who had 9,700 hours, was seated in the front seat giving instruction for an airplane check-out to the private pilot in the rear seat of the biplane, who had logged about 1,700 hours. The engine lost power on takeoff and the airplane crashed in a field.
The post-crash examination did not uncover any pre-impact mechanical malfunctions or failures that would have precluded normal operation, however the mixture control lever, which was located below and to the left of the rear-seated pilot’s left knee, was pulled out about 2 inches.
There was no mixture control lever in the front seat. The lever should have been full forward during takeoff. The propeller control was situated directly below the mixture control and found in the full forward position. The propeller control lever is usually adjusted by the pilot after takeoff.
Although the mixture and propeller control levers were color-coded, it’s possible that the 6-foot, 5-inch private pilot’s left knee blocked his view of the controls due to his size and the small cockpit. The mixture control knob was slightly larger than the propeller control knob, but both were similar in shape.
Investigators determined that it was possible that the pilot thought he was adjusting the propeller control rather than the mixture control on takeoff and inadvertently shut off fuel to the engine.
Probable cause: The pilot’s inadvertent pulling of the mixture control lever on takeoff, which shut down the engine.
NTSB Identification: CEN11FA616
This September 2011 accident report is provided by the National Transportation Safety Board. Published as an educational tool, it isintended to help pilots learn from the misfortunes of others.