Incident Overview
A homebuilt aircraft experienced an in-flight upset while the pilot was conducting Phase I flight testing and exploring the upper flight envelope. According to the official investigation, the incident occurred as the aircraft descended through 4,000 feet mean sea level (msl) at a speed between 115 and 118 mph. At that moment, the aircraft began to flutter. The pilot responded by reducing engine power and raising the nose, but then heard a loud 'pop' sound. Subsequently, the aircraft went out of control and rolled to an inverted position.
Emergency Response
Faced with the loss of control, the pilot activated the aircraft's ballistic recovery parachute system. The parachute deployed successfully, and the aircraft, along with the pilot, descended and landed in an orange grove. The landing in the grove likely cushioned the impact, though the investigation report does not specify injuries or damage to property beyond the aircraft.
Postcrash Examination
After the incident, a postcrash examination was conducted. The examination revealed that two fuselage longerons had fractured. The manufacturer had previously determined the never-exceed speed (Vne) for this aircraft model to be 120 mph. The source does not state whether the flutter was directly caused by exceeding the Vne or by other factors.
Investigation Notes
The investigation focused on the sequence of events and the condition of the aircraft. No analysis or conclusions regarding cause or contributing factors are provided in the source material. The incident underscores the inherent risks of flight testing, particularly when exploring the upper limits of an aircraft's performance envelope.