Boat One
Boat One was the presidential aeroplane of UNIT, created as part of an international agreement on incursion protocols. Under this agreement, in the event of a full-scale invasion, a President of Earth with complete authority over every nation state was immediately inducted. It was decided the only practical candidate for this role was the Doctor.
This induction was performed during an invasion of Earth by an army of Cybermen converted from the dead by Missy. Having stumbled upon the invasion, the Twelfth Doctor was captured and taken aboard by UNIT, where he was inducted as Earth president. Missy was also briefly contained aboard the aircraft.
During flight, the Cybermen attacked the plane. They broke the windows and dragged Colonel Ahmed from the aircraft, while also allowing Missy to escape her confinement. Missy tormented and killed Osgood, before breaching the hull and allowing Kate Stewart, the Doctor and the TARDIS to be blown out of the fuselage. The Doctor managed to summon his TARDIS to him with a TARDIS key while Kate was saved by the Cyberman version of her father.
At Missy's instruction, the Cybermen blew up Boat One. (TV: Death in Heaven)
At a later point in Earth's history, the presidential aircraft was instead named the EP One. (AUDIO: War Against the Laan)
