Navigation Slide Controls
(aka Space-Time Coordinate Programmer)
Also known as the Helmic Orientators, these slide controls (some consoles have a keyboard) and binary selectors are used by the operator for setting the Space-Time Coordinates. The coordinates must take into account the motion of objects relative to a TARDIS's current location, gravity's distortion of the Space-Time Vortex, and the exact time the operator wishes to travel to.
The Space-Time Coordinates are given relative to Galactic Zero Center (the Center of Mutter's Stellian Spiral). They consist of fifteen digits. While it may seem unlikely that a fifteen digit set of coordinates could precisely locate any point in space and time it should be noted the Gallifreyans might not have a base 10 counting system. The first two digits designate the Vector, the second two the Quadrant, the next seven digits represent the exact spatial location, and the last four digits represent the temporal location. These last digits advance steadily as a TARDIS "moves" forward in time. It should be noted that the Directional Unit doesn't do 'BC' and all dates will need to be positive. For more information see the entry Astral Map
Once the numerical sequence is known, setting the coordinates with the Slide Controls is a simple matter. The first eleven digits are input into the Geographical and Interstellar Destination controls. The remaining four are input into the Temporal Destination controls. In theory a fully functional and properly tuned TARDIS can be navigated to a temporal precision of a millisecond, and within a meter of a desired spatial location. As might be expected it is quite tricky to materialize on a ship in flight. The navigational systems can be set up to follow a program that was pre-set in the computer or stored on an external data source like a DVD. A timer can also be set to engaged the program if desired. If the TARDIS receives a signal from a Spatio-temporal Alarm Beacon then its triangulated coordinates can be used as the destination coordinates.
Care should always be taken when setting the coordinates. A hard impact to the navigational panel could knock the xion crystals out of alignment, causing the passivator to go into flux and leak green coolant into the aethiopathic chamber. Without coolant the positioning system will overheat and the thermal cut-out would trigger, preventing any space-time trips from being made. To ensure the coordinates aren't accidentally altered after being set, one of the twin navigational locks can be enabled. One locks manually input coordinates and the other is responsible for the Fast Return Switch. If the coordinates should become fused a TARDIS would only be able to travel between its current coordinates and the last time zone it visited. This would probably achieved by using the Fast Return Switch. If the coordinates are miss-set in such a way as to present the Directional Unit with an unsolvable equation a symbolic resonance could occur in the Trachoid Time Crystal, trapping a TARDIS in a fractal Zenos Paradox forever. Such a paradox would send a TARDIS into the cracks between dimensions and prevent the TARDIS from ever materializing. The TARDIS would remain trapped until the Vortex had eroded away everything except its foundational principles.
The operator should always avoid travelling back in time without first altering the spatial coordinates. If this is not done the TARDIS might materialize inside its younger self. The TARDIS will use the Cloister Bell to warn the operator if this is about to occur. It will also ring the bell if Coordinates are entered that would require the TARDIS to materialize inside solid matter.
All flight information is stored by the Banshee Circuits, which serve as a flight recorder. Proper maintenance is necessary to ensure accurate space-time jumps. If this maintenance is neglected for too long, the Programmer will wear out. For this reason it is recommended that an operator have their TARDIS's navigation systems recalibrated and serviced every 500 years.
The following color code is used:
- Black: For information from the TV Series, including Dimensions in Time, and 1996 TV Movie.
- Blue: For information from the Novels and Audios including Target, Virgin, BCC, and Big Finish.
- Green: For information from 'licensed' reference sources such as the Technical Manual, Doctor Who Magazine, and the Role Playing Games.
- Red: For information from unofficial sources -The Faction Paradox series, behind the scenes interviews, author's speculation, and popular fan belief.
The TARDIS Technical Index is copyright Will B Swift.