Vator

The Vators were the major transportation method aboard Starship UK. They were run by Vator Verse, and 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" to the star whale, who was willingly conducting the ship. The star whale consistently set the children free. Just this happened to, among others, Timmy. (TV: The Beast Below)

"Vator" is likely a contraction of "elevator."