Unannounced glider forces a Saab 2000 to take evasive action in controlled airspace

An unidentified glider crossed the Zürich terminal control area at about 1800 m without contacting air traffic control or squawking a transponder, and turned toward an inbound Saab 2000 airliner at the same level; the crew took evasive action, and there was no collision or injury. The commander, under radar vectors, suddenly saw the glider at his 11 o'clock about 0.6 km away and turning in, and manoeuvred to avoid it. With the glider neither on the radio nor on radar, the controller could not separate the two. In principle the risk of collision was very high, cut by the excellent visibility that let the crew see the glider in time.

1. Glider transiting controlled airspace: An unidentified glider was crossing the Zürich terminal control area (class C) at about 1800 m.
2. No radio, no transponder, no radar: The glider was not in contact with air traffic control and squawked no transponder code; it did not show on the controller's radar.
3. Controller cannot separate traffic: Unable to see or contact the glider, the controller could arrange no separation from an inbound airliner.
4. Glider turns toward the airliner: At the airliner's 11 o'clock, about 0.6 km away and at the same level, the glider turned in toward it.
5. Evasive turn avoids collision: In excellent visibility the Saab 2000 crew saw the glider and manoeuvred clear; there was no collision and no injury.