Beech A23 N8771M accident near Laytonsville, Maryland

Probable cause

The pilot’s failure to ensure that the fuel selector handle was correctly positioned, which resulted in an interruption of fuel to the engine and a loss of engine power during the takeoff, which necessitated a turn away from the trees at the end of the runway and the subsequent stall.

NTSB analysis

The pilot performed a preflight inspection and fueled the airplane with no anomalies noted. He performed two takeoffs and landings without incident. Before the third takeoff, the pilot verified that the flaps were retracted for takeoff and that the left fuel tank was selected. The pilot applied power to take off and released the brakes. As the airplane rolled down the runway, it lifted off the ground, and then settled back onto the runway. The pilot stated that he continued to apply full power but that the airplane was not performing as well as on the previous takeoffs. The airplane eventually became airborne. The pilot stated that he initiated a turn to the right in order to avoid striking trees off the end of the runway; the flight instructor subsequently took the flight controls as the right turn became steeper and the airplane began to descend. According to a witness, the airplane appeared like it would not clear the trees, banked right, and then entered a spin before impacting the ground.

Postaccident examination of the fuel selector revealed it was in a mid-range position, with neither the left or right tank selected. When the fuel selector was placed to the center position, similar to where it was found after the accident, fuel would not flow through the fuel selector. Thus, it is likely that the pilot did not turn the fuel selector completely so that it was not locked in the detent, which restricted fuel flow and resulted in a loss of engine power. In addition, the main fuel line and the return fuel line were removed and there was no fuel present.

A postaccident engine teardown was performed and the fuel manifold was disassembled; dry rot was noted on the manifold diaphragm and it was leaking. The leak might have reduced fuel consumption, but not a significant amount. It is likely that, because of the loss of engine power, the airplane would not have been able to adequately climb above the trees off the end of the runway. Therefore, the pilot attempted to avoid the trees and initiated a turn during the initial climb, which resulted in an aerodynamic stall and subsequent spin.

Although postaccident testing indicated that the flight had adult-onset diabetes, it could not be determined if the flight instructor experienced symptoms from the condition or side effects from the medication that treated the diabetes, which could have hindered his ability to operate the airplane. Furthermore, the flight instructor did not report the diabetic condition or medications on his most recent application for an Aviation Medical Certificate.

Text from the NTSB. Open the NTSB docket for ERA12FA458 for the full record.