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 Time Rotor is considered to be connected to the lower engines; hence as the TARDIS moves the rotor moves accordingly. Its up-down motion may be significant of the way the engines work. As well as signifying the TARDIS' movement, the rotor has also been known to malfunction or stop working when something goes wrong e.g. the rotor stops moving as the TARDIS engines are stalled, rectified by the Doctor bumping the console (Doctor Who).

The rotor, as it has varied through designs, has alternated between being a single column or a series of components that move into each other from above and below. An example of the multiple columns would be in the Ninth Doctor's TARDIS and the Eighth Doctor's also. Currently in the TARDIS of the Eleventh Doctor it is a single component, much like in the earlier versions.

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.