Traffic cop

The Airport Movement Area Safety System (AMASS) receives position data from

an Airport Surveillance Radar Model 9 (ASR-9) system, which pinpoints landing

aircraft, and a Surveillance and Communications Interface Processor (SCIP).

The radar tracks the aircraft to predict where it will land and determines

whether it is in the path of another aircraft or vehicle. That data is transferred

through the Terminal Automation Interface Unit (TAIU) to the AMASS processor.

Separately, an Airport Surface Detection Equipment Model 3 (ASDE-3) radar

searches the ground from the top of an air traffic control tower to detect

vehicles and aircraft on the runways. If a collision is possible, an audio

alarm sounds and a visual alert appears on the controller's AMASS display.