What happened
On January 25, 2016, a Piper PA-28RT-201T, registration EC-KUU, departed from Los Martínez del Puerto aerodrome for Almería. The pilot, the sole occupant, had not filed a flight plan prior to departure due to mobile phone coverage issues, attempting instead to communicate via telephone to the Alicante ARO office.
While flying near Cabo de Gata, the aircraft experienced a total electrical failure. This loss of power disabled all navigation instruments and communication equipment. With the sun approaching sunset and the risk of mid-air collision deemed too high due to the lack of lights and radio, the pilot decided to seek an alternative landing site. After flying over the sea, the pilot located a beach near Punta Entinas and performed an emergency water landing approximately 20 meters from the shoreline. The aircraft, with landing gear and flaps retracted, submerged in shallow water. The pilot successfully evacuated the aircraft and swam to shore, where he remained until being found unharmed the following morning.
The investigation
The investigation examined the aircraft's electrical system and the pilot's flight preparations. Investigators discovered that a car battery had been installed in parallel with the aircraft's primary battery in the baggage compartment to compensate for the aircraft battery's poor performance.
Furthermore, the investigation found that the communication equipment was configured such that the aircraft could only receive signals on COM1 but was unable to transmit, as the radio selector was set to COM2, which was powered off. The transponder was also transmitting an incorrect, unassigned code. The investigation also noted that the pilot had left high-consumption electrical components, such as landing and position lights, switched on following the initial failure, which further depleted the remaining electrical capacity.
Findings
- The primary cause of the accident was the emergency water landing in shallow waters resulting from a total electrical failure.
- The installation of an automotive battery in parallel with the aircraft battery increased the alternator's load, eventually leading to the depletion of electrical power.
- Inadequate flight preparation, including the failure to file a flight plan and the lack of sufficient mobile battery charge for communication, contributed to the event.
- Improper management of the electrical system, specifically leaving high-load lights active after the failure, prevented the recovery of essential low-power functions like the radio.