The Grey alien ship was a spacecraft used by the Grey alien, Seruba Velak. It was shot down by pirates and crashed on Earth. It was then taken to Area 51.
In 1958, the Tenth Doctor escaped in the ship, but it was caught by U.S. soldiers. Later, Seruba Velak and Rivesh Mantilax left in the ship. (TV: Dreamland)
Later, Androvax programmed Nanoforms to rebuild the ship on top of Genetec Systems. A Judoon platoon captured Androvax and used the ship to return to the Shadow Proclamation. (TV: Prisoner of the Judoon)