What happened
On June 12, 2021, at approximately 17:29 local time, a mid-air collision occurred 350 meters west of Piz Neir in the Surses municipality, Switzerland. The accident involved a DR 400/140 B motor aircraft, registration HB-KLB, and an ASW 27-18 glider, registration HB-3412.
The glider, flying a private cross-country route from Amlikon, was descending toward Piz Neir at an altitude of approximately 3,450 meters. Simultaneously, the motor aircraft was en route from Samedan to Locarno. The pilot of the HB-KLB had recently communicated with the Zurich Flight Information Centre (FIC), stating an intention to fly via the San Bernardino pass.
During the flight, the HB-KLB was traveling along the right side of the valley toward the Julier Pass. The two aircraft collided at an altitude of nearly 3,200 meters. The propeller tips of the HB-KLB struck the underside of the HB-3412's left wing, and a secondary impact likely occurred between the tail sections of both aircraft.
The impact caused the HB-KLB to lose parts of its horizontal stabilizer, leading to a crash into a snow-filled depression. All 4 occupants of the motor aircraft were killed. The glider pilot attempted to deploy a parachute and exit the cockpit, but the aircraft struck a steep slope, and the pilot sustained fatal injuries. There were 5 total fatalities across both aircraft.
The investigation
The investigation by the Swiss Transportation Safety Investigation Board (SUST) utilized radar data, radio communications, flight data from the HB-3241, video and photographic evidence from the HB-KLB, and webcam footage.
Investigators examined the flight paths of both aircraft and the sequence of communications with the Zurich FIC. The investigation also reviewed the search and rescue (SAR) timeline, which began after the glider pilot was reported missing and expanded when the wreckage of the second aircraft was discovered by a search helicopter the following day. The investigation also looked into the functionality of the Emergency Locator Transmitters (ELT) on both aircraft.