What happened
On June 25, 2011, a Cessna 172 D departed Heringsdorf Airport (EDAH) for a scheduled 30-minute sightseeing flight. The pilot was accompanied by guests, including one passenger who was seated in the rear right seat and used a walking aid due to a foot injury.
During the approach to runway 28, the pilot reported engine roughness and a drop in RPM. The pilot noted that these fluctuations appeared to coincide with the rear passenger moving to the other side of the cabin to take photographs. Radar data confirmed the aircraft drifted east during the extended approach before the pilot corrected the heading toward the runway threshold. Witnesses observed the aircraft losing altitude during this phase.
In an attempt to perform an emergency landing, the pilot brought the aircraft down into a ditch crossing a field. The impact caused the nose and right main landing gear to collapse, resulting in significant damage to the airframe and the aircraft's engine components. Three persons sustained serious injuries during the accident.
The investigation
The BFU examined the aircraft's mechanical condition and the cockpit environment. Investigators found that while fuel was present in both tanks, no fuel was found in the carburetor float chamber. The investigation focused on the position of the fuel selector valve, which was found in an intermediate position (approximately the 11 o'clock position).
Testing conducted at Eberswalde/Finow demonstrated that while the valve could not be moved from the "Both Tanks" position by a foot, it could be moved from the "Left Tank" position to the 11 o'clock position using the heel of a left foot. This suggested that the passenger, while moving in the rear seat, could have inadvertently bumped the selector.
Additionally, the investigation noted discrepancies in the aircraft's documentation, including an unlisted Garmin 150 XL GPS and a weight and balance discrepancy. The aircraft's engine also showed signs of neglected maintenance, such as a chafed vacuum hose and an unidentified, non-functional cockpit control.
Findings
- The primary cause of the accident was an interruption in the fuel supply to the engine during the approach.
- This interruption was likely caused by the unintentional movement of the fuel selector valve by the passenger's foot.
- The emergency landing was unsuccessful because the pilot attempted to land at a site where a ditch, obscured by vegetation, was encountered at minimal airspeed.