Vator

The Vators were the "London Underground" system of Starship UK. They were operated by Winders and/or Smilers.

Children who got a zero in a test were not permitted travel on-board a Vator — they had to walk home. If they tried to ride it, they would be sent "below." Just this happened to Timmy. "Below" was a star whale, the last of its kind, who was willingly conducting the ship, and who set the children free. (TV: The Beast Below)


 * "Vator" is likely a contraction for "elevator."