Time rotor

The Time Rotor is a component in the central column of the TARDIS console. When the TARDIS is traveling the rotor rises up and down until it has reached a destination. It is associated with the 'whooshing' noise heard when the TARDIS is in flight. The aesthetic design, along with the rest of the TARDIS, has periodically changed throughout the Doctor's travels.

The console in the TARDIS' secondary control room was strangely lacking in a Time Rotor for some reason. (DW: The Masque of Mandragora)

Behind the Scenes

 * It is interesting to note that in the non-canon Dalek movie spin-offs, Doctor Who and the Daleks and Daleks - Invasion Earth 2150 AD, the Tardis lacked the time rotor or even a central console.