What happened
On June 23, 2011, a Beech C24R, registration N38029, was conducting a night instructional flight at Eglin Air Force Base (VPS) in Valparaiso, Florida. The flight, operated by the Eglin Air Force Base Aero Club, involved a flight instructor and a private pilot under instruction performing a 360-degree power-off approach, a maneuver used to practice simulated engine failures.
Radar data and radio communications show the aircraft began the maneuver at approximately 2,000 feet. As the aircraft progressed through the pattern, the altitude decreased significantly; the aircraft was at approximately 400 feet at the 180-degree position and 500 feet at the 90-degree position. After being cleared for the option, the aircraft descended to 1,100 feet over the runway and began a right turn away from the runway. At 900 feet, the instructor notified the controller that the crew was performing another 360-degree circuit.
Following this transmission, there were no further radio communications. Witnesses on the flight line reported hearing the engine sputter followed by a sudden increase in power. They observed the aircraft descend at a steep angle and impact the aircraft parking ramp. The impact caused a post-crash fire, and the aircraft came to rest in the infield. The flight instructor and the student pilot were both fatally injured.
The investigation
Investigators examined the wreckage and found the airplane impacted the parking ramp in a left-wing-low, nose-down attitude. The left main landing gear separated from the airframe, and the left wing was destroyed following a collision with an external power cart. The engine remained attached to its mounts, and the propeller blades showed ground scars indicating power was being applied at the time of impact.
While a post-crash fire prevented a full examination of all engine components, investigators found that one fuel injector was completely blocked and another was partially blocked, though these obstructions were likely caused by thermal damage from the fire. The investigation also noted a previous instance where a pilot had experienced an engine failure in the same aircraft approximately 12 months prior, though maintenance personnel could not duplicate the issue at that time.
Findings
Analysis of radar data and the wreckage path indicated that the crew likely failed to adequately monitor the aircraft's airspeed. This lack of airspeed management resulted in a right-turning aerodynamic stall. Although the pilot attempted to recover the aircraft by adding power, the aircraft was at an insufficient altitude to avoid the ground.