SIDRAT

A SIDRAT (pronouced "sigh-drat", not "sid-rat") was a type of space-time vehicle used by the War Lords and built with the assistance of the War Chief, a renegade Time Lord.

While similar to TARDISes, SIDRATs were somewhat less developed space-time travelling machines. It has also been stated that they are the most basic kind of TARDIS, possibly early TARDIS prototypes. The Second Doctor found it wasn't "difficult" to figure out the operation of the machines. Also like TARDISes, they were larger on the inside than on the outside. Unlike Gallifreyan TARDISes the dimensions of thier interiors could be changed at will. According to Jamie they were green in color.

The Time Lords discounted them as viable space-time transports due to their short range and power costs. From the outside they resembled featureless rectangle boxes, similar in appearance to a form sometimes used by TARDISes while on Gallifrey (possibly a "default" exterior for TARDISes). The War Lords employed them both to abduct Human soldiers for the war games, and also to travel back and forth from the game area to their base. (DW: The War Games). They were operated by remote control.

The supply of SIDRATs to the War Lords was the primary contribution of The War Chief to thier experiment. Without the secrets of space-time travel the War Lords were dependent on The War Chief, and this was reflected in his rank: second only to The War Lord himself. To force the Doctor's compliance, the War Chief trapped him within a SIDRAT and shrunk its inner dimensions until the Doctor and Jamie were nearly crushed. Later the Doctor confronted the War Chief with a revelation: a timeship with a malleable interior was inherently unstable. The War Chief's SIDRATs would never last long enough to prosecute the larger plan of galactic conquest. The War Chief admitted he was aware of this and begged the Doctor to help, promising him half the galaxy after he betrayed his alien allies.

SIDRAT was an acronym for "Space and Inter-Dimensional Robot All-purpose Transporter". (DWN: Doctor Who and the War Games).

Behind the scenes

 * SIDRAT is "TARDIS" backwards.