Time rudder
From Tardis Wiki, the free Doctor Who reference
Time rudders were parts of a space-time vessel which allowed for control in the Time Vortex.
The escape shuttle in which the Eighth Doctor, Liv Chenka and Helen Sinclair found themselves did not have any time rudders, being incomplete as many parts of the Crucible of Souls were at the time. (AUDIO: Ship in a Bottle)
