With the Autopilot and TRACK mode engaged, the lateral mode of the autopilot can be changed by rotating the Nav Selector to the respective position: 

• BOMB – all heading indications by the heading pointer are magnetic.
• REMOTE – heading information is controlled by the GPS (if fitted) and the flight plan that has been set in the world map prior to loading the flight.
• Central (Normal) – heading information is controlled by the TACAN receiver.
• LOC – ILS localiser beam signals are fed into the system. The BEAM flag on the director horizon shows and the beam bar on the beam compasses indicates the aircraft position relative to the beam.
• GP – both localiser and glidepath signals are fed into the system. Both the BEAM and the GP flag show on the director horizons and the glidepath pointer moves relative to the centre dot to show the relative position of the glidepath to the aircraft.

Note 1: In order for the Autopilot to capture and fly a glideslope, the GLIDE button must also be pulled once the glideslope has been intercepted. 

Note 2: The Vulcan’s autopilot doesn’t have any ability to ‘arm’ an autopilot mode with the autopilot engaged, and therefore, as soon as a mode is selected the aircraft will immediately fly the correct course to interpret the heading/beam/glideslope, etc. This is especially important to note during ILS approaches, as LOC/GLIDE modes should only be engaged once the aircraft has intercepted the ILS beam.