Event Overview
On 16 December 1999, a Piper PA-34-200 twin-engine aircraft departed Berlin-Schönefeld at 08:15 local time for a private flight to Riga. The crew consisted of a pilot, a co-pilot handling radio communications, and one passenger. The flight was planned as VFR initially with transition to IFR.
Shortly after takeoff, before the landing gear retraction was complete, a total electrical failure occurred. The pilot checked the circuit breakers and cycled the master and generator switches, but the cause could not be identified. The pilot decided to divert to Finow for landing and operated the remainder of the flight under VFR.
Landing Gear Issues
During the approach, the landing gear was extended using the emergency system because the main electrical system was inoperative. The occupants could only see the nose gear via a mirror, and it appeared extended. However, the landing gear was only partially extended and not locked. Upon touchdown, the aircraft settled, and the fuselage and propeller contacted the ground.
After the aircraft was lifted, the landing gear extended and locked normally without assistance. Subsequent tests using the aircraft's battery showed that the gear could be extended and retracted without problems, and the emergency extension system functioned correctly.
Electrical System Examination
No technical defect was found in the electrical system. Both generators engaged at 1500 RPM, and all instruments operated normally. It was determined that either a non-reproducible fault (e.g., a stuck relay) occurred, or the pilot inadvertently switched off the master switch, cutting power to both generators and causing the total electrical failure.
Additional Findings
The aircraft's certificate of airworthiness did not permit operation under IFR conditions, but this was not considered relevant to the accident.
Probable Cause
The accident was due to either a non-reproducible electrical fault or a possible pilot error by inadvertently switching off the master switch. The resulting electrical failure prevented the landing gear from being extended with the main system. When extended with the emergency system, the gear did not lock, leading to collapse on landing.