What happened
On 12 November 2011, a Piper PA-28-181, registration G-BXRG, departed Lee-on-Solent for Alderney. During the flight, the aircraft experienced a significant electrical malfunction. The passenger noted that the illuminated digits on the communication and navigation control panels extinguished, and the GPS display subsequently went blank.
Following this failure, the aircraft's track deviated significantly from its intended route. The pilot, unable to confirm his position due to the loss of electronic navigation, eventually identified a commercial vessel in the area. To avoid the risks of flying uncertainly in changing weather, the pilot elected to ditch the aircraft near the vessel. The ditching was executed successfully, but while the passenger managed to escape the sinking aircraft, the pilot was unable to exit before the plane was lost at sea. The passenger sustained minor injuries, while the pilot suffered a fatal injury.
The investigation
The AAIB examined radar data, radio communications, and the aircraft's electrical systems. Radar tracks showed the aircraft's transponder code changed to 7600, indicating a radio failure, and the aircraft's track became erratic before disappearing from radar. The investigation also reviewed the aircraft's fuel levels, estimating approximately 54 litres of fuel remained at the time of the accident.
Findings
- The primary cause of the electrical failure was likely the loss of the alternator, leaving the aircraft to rely solely on battery power.
- As the battery voltage depleted, various avionic units lost power sequentially.
- The loss of electrical power from the alternator led to the loss of GPS and radio functionality, causing the pilot to become uncertain of his position.
- The pilot's decision to ditch was a calculated choice to avoid the increased risks of navigating by compass alone in uncertain conditions.
- The pilot's inability to exit the aircraft during the ditching remains undetermined, though it may have been due to a minor entanglement.