What happened
On April 23, 2014, a pilot initiated a local flight from the Wildberg landing field in a P.P.H.U. Ekolot KR030 Topaz ultralight aircraft. At approximately 09:25, the pilot contacted the Leutkirch tower to announce an intended touch-and-go maneuver. After receiving updated landing information, including runway 24 and an altimeter setting of 1019 hPa, the aircraft touched down on the runway.
According to the tower controller, the aircraft rolled approximately 300 meters before lifting off again at a low speed of less than 80 km/h. Upon reaching an altitude of roughly 10 meters, the left wing dipped, and the aircraft entered a climb with a 90-degree change in direction. Shortly after attempting to level the aircraft, the KR030 Topaz pitched steeply downward from an altitude of approximately 30 meters, striking the ground on its left wing. The pilot sustained fatal injuries, and the aircraft was destroyed.
The investigation
The BFU investigation examined the aircraft's flight history, the pilot's experience, and the mechanical state of the aircraft. The pilot had 45 hours of total time on aerodynamically controlled ultralight aircraft, with only 4 hours and 40 minutes of experience specifically on the KR030 Topaz.
Investigators noted that the aircraft's flight manual describes specific stall characteristics, including a tendency for the aircraft to pitch nose-down during a stall. The investigation also reviewed the aircraft's maintenance records, noting a recent annual inspection in April 2014. Physical examination of the wreckage revealed that the propeller blades had broken off at the hub and the wing attachment to the fuselage was fractured. The cockpit flap indicator was set to position 2 (+40°), and the trim was set to a slightly nose-heavy position.