What happened
On April 1, 2007, at approximately 10:15 UTC, a Piper PA34-200T Seneca II crashed in a forested area of the Ossiacher Tauern in Carinthia, Austria. The aircraft was conducting a VFR flight from Ingolstadt, Germany, to Klagenfurt, Austria.
During the flight, the pilot encountered deteriorating weather conditions. After initially deciding to divert to Graz, the pilot subsequently decided to return to the departure airfield of Ingolstadt. During this turn, the pilot informed Klagenfurt Radar that the aircraft was operating in IMC (Instrument Meteorological Conditions). Following instructions from air traffic control to climb to flight level 120 and head north, the aircraft exhibited significant fluctuations in heading, altitude, and airspeed. The aircraft then disappeared from radar and disintegrated in flight due to extreme structural loads.
The investigation
The SUB investigation reconstructed the flight path using radar data from the Koralpe station, air traffic control transcripts, and witness accounts. The investigation examined the aircraft's wreckage, including the broken vertical stabilizer and cabin structure. Technical analysis focused on the aircraft's flight parameters, the pilot's weather briefing, and the structural integrity of the airframe during the high-load event. The investigation also reviewed the pilot's decision-making regarding the transition from VFR to IMC flight.