What happened
On November 24, 1999, an EC 135 helicopter, operating on a police mission to monitor traffic accident hotspots, crashed into a wooded area near Basepohl, Germany. The aircraft had departed from Neubrandenburg airfield at 14:12 local time following a refueling stop.
Witnesses on the ground, including soldiers at the former Basepohl airfield, observed the helicopter flying at a very low altitude on a southern course. The flight path subsequently transitioned into a climb, followed by a turn to a western course and a steep descent. During this descent, the aircraft disappeared behind a line of trees. The helicopter struck trees at an altitude of approximately 10 meters, which caused the destruction of all four main rotor blades. The aircraft then traveled approximately 100 meters through the woods in an uncontrolled trajectory before impacting the ground. The accident resulted in 3 fatalities and 1 person seriously injured.
The investigation
The BFU investigation included on-site examinations and technical analysis of the wreckage, which was transported to Laage Air Base. Investigators examined the flight control linkages, tail rotor drive, and various electronic memory units, including the Warning Unit, CAD, VEMD, and EEC.
Technical evaluations conducted in France and the USA by the manufacturer showed no evidence of mechanical failure. While the VEMD and CAD recorded an overspeed warning, this was attributed to the extreme flight maneuvers performed just before impact. Error messages in the EECs were traced to sensor and switch failures caused by the physical impact of the crash itself. Radar data reconstruction confirmed the flight path observed by witnesses, showing the aircraft flying as low as 20 feet above the ground during its southern leg.
Findings
- The aircraft was mechanically sound and fully functional prior to the collision.
- The pilot was experienced, with 3,150 total helicopter flight hours and 170 hours on the EC 135.
- The aircraft was within its permissible weight and center of gravity limits.
- The pilot conducted a low-altitude flight without sufficient safety margins, performing maneuvers in close proximity to obstacles.
- A flight dynamic analysis by the manufacturer concluded that an effective recovery maneuver was possible if the pilot had applied the necessary cyclic and collective inputs in a timely manner.
- The investigation could not determine the specific pilot error that led to the collision, though it noted that the high maneuverability of the aircraft might encourage aggressive flight profiles.