Definition
A traffic alert issued by an airborne collision avoidance system that not only warns of a potential conflict with another aircraft but also recommends a specific vertical maneuver — climb or descend — to resolve it. On modern systems such as ACAS X, the CRA is the resolution-stage advisory that tells the pilot what to do, building on the earlier traffic-alert stage.
Plain English
An automatic cockpit warning that another aircraft is too close and tells you exactly which way to move — up or down — to stay safely apart.
Context Anchor
Seen in avionics, traffic-alerting, or air traffic control automation discussions where computers help detect and resolve possible traffic conflicts.
Derivation
Conflict here means two aircraft on paths that will bring them too close together. Resolution means fixing or settling that situation. Advisory means the system is recommending an action, not commanding it — though pilots are expected to comply promptly.
Why Pilots Care
Following the advisory maintains safe separation and prevents a collision that could occur within seconds.
Intuition Check
Do not read “advisory” as casual advice. In aviation, an advisory may require prompt attention and the correct procedure, even though the pilot remains responsible for the aircraft.
Example Sentence 1
The crew received a CRA to climb and immediately disconnected the autopilot to follow the advisory.
Example Sentence 2
The pilot responded to the CRA by adjusting pitch attitude as shown on the vertical speed indicator.