What happened
On September 14, 2007, at approximately 09:20 UTC, a SWING ultralight aircraft, registration OK-DUO 10, crashed in the town of Varnsdorf. The flight originated from the Hradčany airfield (LKHR-U). During the flight, the pilot notified air traffic services of his intention to enter the Šluknov protrusion airspace and fly toward Varnsdorf.
While flying at a very low altitude over the town, the pilot performed a 180-degree turn over the center of the city. As the aircraft approached the state border, the pilot executed a sharp left turn, likely in an attempt to avoid crossing the boundary. This maneuver caused the aircraft to lose airspeed and enter a spin. Witnesses observed the aircraft descending rapidly at an altitude of approximately 30 meters before it pitched steeply toward the ground, impacting the earth at a near-vertical angle. The impact resulted in two fatalities, involving the pilot and a passenger.
The investigation
The ÚZPLN investigation established several critical irregularities regarding the flight's legality and the aircraft's configuration. The investigation found that the pilot was flying with an expired pilot license and an invalid medical certificate. Furthermore, the aircraft was operating in an unairworthy state due to an overweight condition; the total weight of the pilot and passenger, combined with the aircraft's empty weight, exceeded the Maximum Take-Off Mass (MTOM) by 59 kg, representing a 13% overload (excluding the weight of fuel).
Investigators also noted that the pilot was likely distracted by other activities, as cameras were found in the cockpit and evidence indicated the pilot was photographing objects in Varnsdorf during the flight. Technical analysis of the wreckage confirmed that the aircraft's control surfaces and engine were functional prior to the impact, and the crash was consistent with a high-energy impact following a spin.
Findings
- The primary cause of the accident was the loss of control during flight maneuvers while operating at low altitude over a populated area.
- The pilot entered a sharp left turn near the state border, which induced a spin.
- The aircraft was significantly exceeding its Maximum Take-Off Mass (MTOM), which contributed to the loss of control.
- The pilot was distracted by photography, which likely prevented him from maintaining proper situational awareness and aircraft control.
- The pilot was not legally authorized to fly due to expired pilot and medical certifications.
- Meteorological conditions and the departure airfield were not contributing factors to the accident.