What happened
On April 24, 2002, a mid-air collision occurred in uncontrolled airspace near Sellingen, involving a two-seat General Dynamics F-16B from the Belgian Air Component and a Dutch Comco Ikarus C42, registration PH-3G8. The collision took place at an altitude between 961 and 1,127 feet. The impact caused the total destruction of the ultralight aircraft, resulting in the death of its pilot. In the F-16B, the forward crew member activated the ejection seats just before or during the collision; while the rear pilot survived, the forward pilot was killed. The F-16B subsequently crashed and caught fire.
The investigation
The investigation was conducted by the Dutch Safety Board (OVV) in collaboration with the Belgian Accident Investigation Unit (ODOV). Investigators reconstructed the flight paths and analyzed the collision height using data from the NLR (Netherlands Aerospace Laboratory). The inquiry examined the effectiveness of the 'see-and-avoid' principle in uncontrolled airspace, specifically looking at the visibility and speed differentials between high-speed military jets and slow-moving civil aircraft. The investigation also reviewed existing regulations regarding minimum flight altitudes and the use of transponders in Class G airspace.
Findings
- The collision occurred in uncontrolled airspace where pilots are responsible for maintaining separation via the see-and-avoid principle.
- Significant speed differentials between the military formation and the ultralight aircraft made visual detection extremely difficult.
- The F-16B was being flown manually during a low-level navigation mission, which can lead to altitude deviations.
- At the time of the accident, a recent regulation had established a minimum flight altitude of 1,200 feet AMSL for military jets in Dutch airspace, but the collision occurred below this threshold.
- The investigation noted that the 'see-and-avoid' concept is insufficient to prevent collisions when such extreme speed disparities exist, even with visibility exceeding 8 kilometers.