heads up display

In Orbiter, the heads-up display is a standard feature of all spacecraft. It has three modes, cycled by pressing the H key; it can also be turned off completely with ctrl-H.

• General information

All HUDs show the current time and camera information in the top right-hand corner. In non-panel modes, they also show engine and RCS status in the top left-hand corner.

• Surface mode

The HUD displays a pitch ladder and a cross-in-circle indicator of the current velocity. (If this overlays the ground, it indicates your projected landing point.) At the top of the HUD is a bearing indicator; this is centred on the vessel's current heading. If a base has been selected in the Map MFD, the direction to that base will be shown as a triangle, either overlaying the bearing strip or pointing off to one side of it. Airspeed and altitude are also shown.

• Docking mode

This mode displays direction and velocity relative to the selected docking target (normally chosen with a nav radio). A box surrounds the target (or a triangular pointer shows the way); a cross-in-circle shows your velocity vector, and a cross shows the opposite vector.

If you want to match velocity with the target, apply thrust towards the cross.

• Orbit mode

This mode displays a pitch ladder relative to the current orbital plane, where the zero line indicates the orbital plane. It also marks the prograde direction with a cross-in-circle and the retrograde direction by with a cross. (If neither of these is on screen, a triangular marker points towards prograde. You can change the reference object with ctrl-R.

See also: http://en.wikipedia.org/wiki/Heads-Up_Display