What happened
On October 18, 2021, at approximately 18:01 local time, a dangerous close proximity between two aircraft occurred while exiting the control zone of Bern Airport (LSZB).
The first aircraft, a Piper PA-28-181 with registration HB-PHU, was conducting a private flight under Visual Flight Rules (VFR). The flight originated from Bern with a planned destination of St. Gallen-Altenrhein (LSZR), carrying one pilot and one passenger.
The second aircraft, a Cessna 182T registered as HB-TCT, was also operating under VFR for private purposes. This aircraft departed from Bern with a flight plan directed toward Grenchen (LSZG) and was occupied by a pilot and a flight instructor.
The investigation
The Swiss Transportation Safety Investigation Board (SUST) initiated an investigation into the event following the report of a serious airprox. The investigation focused on the maneuvers performed by both aircraft as they transitioned out of the Bern control zone.