According to the AIM, in class B and C airspace separation of VFR traffic is "suspended during CENRAP operations":

Separation of VFR aircraft will be suspended during CENRAP operations. Traffic advisories and sequencing to the primary airport will be provided on a workload permitting basis. The pilot will be advised when center radar presentation (CENRAP) is in use.

What is CENRAP, how are pilots informed that it's in use (i.e. what is the radio phraseology?) and what action is expected from pilots in that case?


CENRAP is when an approach control uses the long-range center radars for the separation of their traffic, instead of their normal radars(maintenance, damage, etc). When in this mode, separation standards increase due to the longer rotation/slower update speeds(which allow the longer range visibility) of the Center Radar.

If you ever hear about CENRAP, it'll usually be on the ATIS, or the radar facility probably won't provide services to VFR aircraft, just due to the degradation of radar quality.

| improve this answer | |

Your Answer

By clicking “Post Your Answer”, you agree to our terms of service, privacy policy and cookie policy

Not the answer you're looking for? Browse other questions tagged or ask your own question.