The ground end of the navigation aid calibration process during the Fokker F.28 era was the Optical Tracker. The Optical Tracker contained a television sensor which tracked a light in the nose of the F.28 as the aircraft in turn tracked the navigation aid course. The telescopic sight on top of the Tracker was used to cue the television-tracker on to the aircraft.

Deviations from the desired flight path were transmitted by datalink back to the flight survey stations aboard the aircraft for analysis. In the photo above, the datalink is in the electroic box at the foot of the tracker.

The Optical Tracker was a joint development between British Aerospace Australia and the Department of Civil Aviation. It was capable of tracking in either elevation or azimuth.