Main Doors

The main doors (aka Real World Interface) are the primary means of ingress and egress from the exterior of the TARDIS to the interior and vice versa. The outside of the main doors can change depending on the Chameleon Preset, but the inside will always be a 3x3 barrier. The main doors, when sealed, will isolate the interior from the exterior completely, obstructing access to either side from the other. The main doors must be closed during takeoff, but can be opened while in flight. Similarly, they must also be closed during landing procedures.

The main doors can only be opened from the outside with the TARDIS Key. This is to secure the TARDIS from possible intruders. From the inside, however, they can be opened by a button at the door or from the Master Control Console (MCC). In fact, the only button on the MCC that still works in a powered-down state is the door control.