Ground Position Indicator GPI Mk.6

The GPI Mk.6 on display here, with its front panel removed to expose its inner workings, is probably the finest airborne analogue computer ever made. An extremely intricate mix of finely machined cogs, metal cams, electrical relays and switches, which would give the operator an accurate readout of the aircraft's position, via the dials on the front panel.

It would have been initially calibrated to the north/south and east/west co-ordinates of the position of the hard standing on which the aircraft would be positioned prior to take off. Once in flight, the unit would receive other navigational aids, together with feeds relating to heading, groundspeed and drift,

All of these tasks could nowadays be easily and quickly accomplished by a computer chip fitting in a mobile phone!

(Colour Photograph Bottom Right) - Ground Position Indicator GPI Mk.6