Airspace

Airspace referred to territory within the sky.

In 1997, the Torchwood Institute shot a Jathaa sunglider down. Ten years later, Yvonne Hartman claimed to the Tenth Doctor that the alien spacecraft had "violated [their] airspace." (TV: Army of Ghosts)

On 6 March 2006, all flights in North American airspace were grounded until further notice following the crash landing of an alien spacecraft in the River Thames in London. (TV: Aliens of London)

During the Year That Never Was, 24 hours prior to Launch Day, the aircraft carrier Valiant entered the airspace of Zone One. (TV: Last of the Time Lords)

On 1 January 2019, the Thirteenth Doctor noted that a Dalek reconnaissance scout was flying through Earth airspace, making it a priority for her and Team TARDIS to stop it before human forces could engage it. (TV: Resolution)