What happened
The accident occurred during a specialized test flight intended for the certification of wing tip tanks. While the crew was conducting spin maneuvers as part of the testing protocol, the aircraft entered a flat spin condition. The pilot attempted to recover control but was unable to exit the spin. Consequently, the pilot ejected from the aircraft and deployed a parachute, landing safely on the ground. The aircraft continued its descent and collided with the terrain shortly after the pilot's ejection.
The investigation
An examination of the incident revealed that there were no mechanical failures or malfunctions reported at the time of the accident. The loss of control was attributed to the aerodynamic conditions encountered during the spin maneuver rather than equipment failure.
Findings
The primary factor in this event was the aircraft's entry into a flat spin from which the pilot could not recover. This occurred specifically while performing spins for the purpose of certifying wing tip tanks. The pilot's decision to eject resulted in survival, but the aircraft was destroyed upon impact with the ground.
Safety message
This incident highlights the inherent risks associated with flight testing, particularly when exploring the limits of aircraft handling characteristics such as spin recovery. Test pilots must be prepared for unrecoverable attitudes during certification flights involving new configurations or modifications.