What happened
On April 15, 2015, a Bölkow 207 departed from the Moosburg airfield (EDPI) for a flight to Mühldorf am Inn. The aircraft, a wooden-structure low-wing monoplane, took off from grass runway 22 in a three-point attitude. Witnesses observed that immediately after liftoff, the aircraft failed to gain altitude or airspeed, instead maintaining a very high angle of attack and oscillating along the longitudinal axis.
As the aircraft progressed down the runway, it drifted to the left. During the final third of the takeoff roll, the left wingtip struck the ground and collided with a metal signpost located beside the runway. The impact tore the sign from its post and ruptured the left fuel tank. The aircraft then slid into adjacent trees and shrubs at the end of the runway, where it caught fire. The pilot sustained fatal injuries.
The investigation
The BFU examined the wreckage, the aircraft's maintenance records, and the pilot's medical history. The investigation confirmed that the aircraft was airworthy, with its takeoff mass and center of gravity within permissible limits. The engine and propeller showed no signs of mechanical failure or malfunction.
Medical examinations of the pilot revealed significant cardiac findings, including coronary artery sclerosis and a history of a previous myocardial infarction. The presence of soot in the pilot's airways indicated that he was still breathing when the fire began, and his position outside the cockpit suggested he had attempted to exit the aircraft before being overcome by the flames.
Findings
- The aircraft was in an uncontrolled flight state immediately after takeoff.
- The collision with the signpost caused the fuel tank rupture and subsequent fire.
- A medical impairment causing loss of consciousness is the most probable cause of the loss of control, given the pilot's documented cardiac condition.
- The pilot's extensive experience as a commercial pilot and instructor made other factors, such as improper power settings or trim, unlikely causes.