Maintaining coastal radar surveillance of helicopters flying to and from offshore oilfields is clearly difficult, since the traffic quickly goes below the radar’s line of sight. As a result, both the Netherlands’ LVNL and the UK’s NATS have chosen multilateration to monitor traffic supporting the North Sea oilfields in their respective territories. Here, the small multilateration receiver stations are easily located on the oil platforms themselves, and provide high accuracy surveillance coverage down to the surface.

Oil Rig in the North Sea