A Visual Communication System

It has long been realized that manual voice-radio and wire telephone communication facilities cannot meet the future requirements of aviation for air traffic control communication services. The operational requirements for an Air Traffic Control Signaling System (ATCSS) are discussed; the relative applicability of a number of existing and proposed communication systems are shown using an arbitrary but consistent rating method. Block diagrams are presented which cover the laboratory experimental equipment of the Melpar Visual Communication System (VCS). A typical sequence of events and their durations for ATCSS service is given. The main conclusion is that a direct viewed bright storage tube display method should be employed in the ATCSS airborne unit, rather than an electromechanical (or ``roller-wheel'') type of indicator system.