Ground Based Systems

CONTROLLERS and Air Traffic Control (ATC) systems are now fully prepared for the introduction into service of the first commercial supersonic transport aircraft, and avionics is playing a major part in providing the equipment for this leap forward in performance. For transatlantic operations, an organised fixed two‐track system is envisaged which will be required for at least the initial two years of service (from 1976) when traffic density in this area will be low. The lateral separation of these tracks will be 60 nautical miles (fig 1) and as supersonic traffic builds up a third track could be provided on the south side of the system.