What happened
On July 17, 1965, a Piper Cub J3C, registration HB-OWV, was conducting a series of landing tests at the Bern-Belpmoos airfield. The flight was part of a training procedure intended to extend the pilot's student license. After successfully completing three landings within the available 150-meter runway area, the pilot attempted a fourth approach. During this final approach, a sudden change in wind conditions produced a headwind, causing the aircraft to fall short of the intended touchdown point. In an attempt to reach the runway, the pilot applied elevator input; however, this caused the aircraft to climb slightly before suddenly dropping. The aircraft struck the ground with significant force, causing the landing gear to collapse and the propeller to strike the ground. The aircraft came to a halt 10 meters from the point of impact, angled 45 degrees to the right with the tail elevated at approximately 50 degrees.
The investigation
The investigation focused on the mechanical integrity of the aircraft and the pilot's handling of the wind change. Investigators examined the damage to the Piper Cub J3C, which included a broken wooden propeller, dented engine cowling, and fractured attachment points on the left front landing gear. While the pilot's reaction to the wind was noted, the technical examination of the landing gear revealed that the two eyelets of the left strut attachment contained pre-existing cracks.
Findings
- The pilot failed to sufficiently account for changing wind conditions, leading to an undershot approach.
- The pilot's attempt to correct the short approach resulted in an unintended climb followed by a sudden descent.
- The landing, while not excessively high, imposed a load on the landing gear that exceeded its remaining structural capacity due to pre-existing cracks in the left landing gear attachment points.