Greyhound Three
From Tardis Wiki, the free Doctor Who reference
Greyhound Three was a UNIT call sign which was used by Mike Yates whilst transporting the TARDIS to the Newton Institute. (TV: The Time Monster) John Benton also used this sign. (TV: The Green Death) It was later used by Captain Josh Carter. (AUDIO: House of Silents, Hosts of the Wirrn, The Curator's Gambit)