What happened
On August 6, 1964, a Piper Cub J3C, registration HB-OEM, was performing the first leg of a supervised 300 km flight. The aircraft, operated by the Birrfeld Flight School, arrived at Montreux airfield at approximately 12:15 PM. The pilot, a student, approached runway 01 into a moderate northern wind.
During the final moments before touchdown, a gust of wind briefly lifted the aircraft by about three meters, prompting the pilot to increase power to continue the landing. The aircraft made contact with the grass runway on its main landing gear within the first third of the 700-meter strip. However, the tailwheel did not touch the ground, resulting in a light wheel landing. As the aircraft's forward momentum decreased, the nose began to pitch upward. The aircraft eventually reached a vertical position on its propeller hub before losing balance and tipping completely onto its back.
The investigation
The investigation examined the aircraft's mechanical condition, the weather, and the pilot's actions. The Piper Cub J3C was found to have functional brakes both before departure from Birrfeld and following the accident. The weather at the time of the incident featured good visibility of approximately 30 km and light northern winds, though some thermal turbulence was present.
Investigators analyzed the sequence of the landing, noting that because the landing was performed into a headwind, a sudden wind shift sufficient to cause a capsize was unlikely. The investigation focused on why the aircraft's nose pitched up so aggressively despite the lack of significant forward speed.
Findings
There were no injuries resulting from the accident. The aircraft sustained damage including a broken wooden propeller, dented engine cowling, a dented rudder edge, and damage to the right wing strut and structure.
The primary cause of the accident was the accidental application of the brakes by the student pilot during or immediately after the main gear touched the runway. This sudden deceleration caused the aircraft to pitch forward onto its nose.