What happened
On January 1, 2015, at approximately 17:17 UTC, a Rans S-6 XL (registration CS-UJF) was performing a local leisure flight at the Beja Aerodrome in Portugal. The aircraft was operated by a private individual and carried one pilot and one passenger.
Immediately after taking off from runway 35, the aircraft entered an abnormal nose-up attitude, eventually reaching an inverted position of approximately 135 degrees. During this maneuver, the passenger interfered with the flight controls. Although the pilot attempted to recover the aircraft using the left stick and left pedal, the aircraft ultimately collided with the ground. The impact occurred with low horizontal velocity and a relatively low vertical speed, which prevented a more catastrophic outcome.
Following the collision, a fire broke out. The slow development of the fire allowed the passenger to escape the wreckage, while the pilot, who had been rendered unconscious by the impact, was subsequently rescued.
The investigation
The GPIAAF examined the wreckage, the flight path, and the circumstances surrounding the boarding and takeoff. The investigation reviewed the pilot's qualifications, the aircraft's maintenance and documentation, and the physical forces involved in the impact. The investigators analyzed the survivability of the crash, noting that the near-level attitude of the aircraft during impact resulted in vertical decelerations that were better supported by the human body than horizontal ones, contributing to the survival of both occupants despite serious injuries.
Findings
- The primary cause of the accident was interference with the flight controls by the passenger.
- The pilot failed to counteract the force exerted by the passenger on the controls in a timely manner.
- The boarding process was rushed due to the approaching sunset.
- The passenger had not received a safety briefing regarding the aircraft.
- Several regulatory and documentation discrepancies were identified, including an expired flight certificate, an invalid medical certificate for the pilot, and a lack of valid civil liability insurance for the owner.
- The aircraft's engine documentation did not match the engine actually installed on the plane, and no mass and balance calculations were performed prior to the flight.
Safety action
- The Portuguese Civil Aviation Authority (ANAC) should take a proactive approach regarding ultralight aircraft with long-expired flight certificates.