What happened
On December 11, 1977, a Beech 35-C33 (Debonair), registration D-EKVI, was conducting a private VFR flight from Basel-Mulhouse to Birrfeld. After completing customs formalities in Basel, the pilot departed at 16:57. Although Zurich Information had notified the pilot that the daylight limit was 17:10, the pilot proceeded with the intention of arriving before nightfall.
By 17:10, the aircraft was flying near Birrfeld in low light. The pilot initially struggled to locate the airfield, which was not equipped with night lighting. Using a yellow blinking light placed by ground personnel for orientation, the pilot attempted an approach to runway 26. During the final approach, the aircraft descended steeply, and the pilot only identified the runway during short final. The aircraft touched down at high speed past the midpoint of the runway. After an initial attempt to brake, the pilot applied full power in an attempt to execute a go-around, but the maneuver was unsuccessful. The aircraft overran the end of the runway, crossed the Hausen-Birrfeld road, and came to a stop in a soft field approximately 120 meters beyond the runway. There were no fatalities among the two occupants, though the aircraft sustained heavy damage to the engine mount, propeller, and nose gear.
The investigation
The investigation examined the pilot's flight planning, the aircraft's configuration, and the environmental conditions at the time of the accident. The pilot held valid licenses, including recent instrument flight training, and possessed significant flight experience. The aircraft was found to be in good mechanical condition, with no technical failures noted in the braking system.
Investigators noted that the landing flaps were set to 20 degrees instead of the required 30 degrees, and the propeller pitch lever was set to high pitch. The weather at the time involved heavy haze and overcast skies, which contributed to the difficulty in maintaining visual references after sunset.