What happened
On March 21, 2022, at 10:42 UTC, a Diamond DA40 NG, registration LN-PFI, was conducting a private cross-country flight from Sandefjord Torp (ENTO) to Billund (EKBI). While cruising at Flight Level 090, the two pilots on board observed an object approaching the aircraft at the same altitude. The object, which was identified as a quadrotor UAV with a black underside and orange top, passed the aircraft with a vertical separation of zero feet and a horizontal distance of only 4 to 5 meters. The encounter occurred under visual meteorological conditions approximately 1.5 nautical miles north of the island of Laesoe.
The investigation
The Danish Accident Investigation Board examined radar and Automatic Dependent Surveillance–Broadcast (ADS–B) data to identify the source of the drone. The review of this data showed no UAV operations in the vicinity of Laesoe at the time of the incident. Furthermore, the investigation confirmed that no Danish military UAV operations were active in the area, and the Danish Civil Aviation and Railway Authority (DCARA) had not granted any special authorizations for UAV flights near Laesoe during that period.
Findings
- The UAV operation at FL 090 was unauthorized.
- The presence of the unidentified drone at the same altitude as the aircraft posed a significant risk to flight safety.
Safety action
To reduce the risk of near-collisions between unmanned systems and manned aircraft, the AIB recommends that all UAV operators strictly adhere to the established legal framework.