Definition
A radar data processing system used by some military air traffic control facilities that automatically displays an aircraft's identity and Mode C altitude directly on the controller's radar scope when the aircraft's transponder is operating. It removes the need for the controller to manually correlate the radar return with separate flight data.
Plain English
A radar system that automatically shows the aircraft's call sign and altitude right next to its blip on the controller's screen, so the controller can see at a glance who you are and how high you are.
Context Anchor
Seen in ATC radar and Pilot/Controller Glossary terminology; it is normally controller-side equipment, not a cockpit control.
Derivation
The name describes the function: the controller reads the aircraft's altitude and identity directly off the scope, rather than having to look it up or ask. 'Direct' here means 'shown to the controller without an intermediate step.'
Why Pilots Care
It reduces the need for voice queries and helps controllers maintain safe separation between aircraft more quickly.
Intuition Check
Identity does not mean the controller automatically knows everything about the aircraft. In DAIR, identity means the identifying information ATC receives electronically, such as the aircraft’s assigned transponder code.
Example Sentence 1
Because the military approach facility used DAIR, the controller could see the aircraft's call sign and altitude on the scope as soon as the transponder was set to the assigned code.
Example Sentence 2
DAIR-equipped radar allowed the tower to identify all aircraft in the pattern without additional queries.