A controller could also briefly lose a commercial aircraft's transponder signal, although this happened much less frequently.

Then the controllers lost their link with the spacecraft's smaller antennas, but that service was restored within an hour.

At 4:21, controllers lost all radar contact with the plane.

Soviet controllers unexpectedly lost radio contact with the craft in April.

Two minutes later, controllers lost contact with the plane.

If wrong, the trapped player assumed control and the outgoing controller loses a life.

Typically the controller will lose the longer range, and later to reply, aircraft just when the former may be most interested in monitoring them closely.

The controllers also lost a feature called route display, which shows them where each plane will go in the next few minutes.

The controller lost radar contact with the flight while it was in the right turn passing through an estimated heading of 240-260 degrees.

However, controllers lost contact with some planes already in the air because some backup radio systems failed.