AIM Text
UNICOM service may be used for ATC purposes, only under the following circumstances:
- Revision to proposed departure time.
- Takeoff, arrival, or flight plan cancellation time.
- ATC clearance, provided arrangements are made between the ATC facility and the UNICOM licensee to handle such messages.
Source: FAA Aeronautical Information Manual · current edition · paragraph 4-1-12.
The short answer
This advisory AIM section explains the narrow circumstances in which UNICOM, a nongovernment air/ground station, may relay ATC messages: a revision to proposed departure time; takeoff, arrival, or flight plan cancellation time; and an ATC clearance, provided the ATC facility and UNICOM licensee have arranged to handle such messages. It is FAA guidance, not regulation.
Research Notes
Common Questions
Can a UNICOM operator give me an ATC clearance?
Only if arrangements have been made between the ATC facility and the UNICOM licensee to handle such messages. Per this AIM guidance, a UNICOM may relay an ATC clearance under that condition, alongside departure-time revisions and takeoff, arrival, or flight plan cancellation times.
What ATC-related messages may UNICOM handle?
The AIM lists three: a revision to proposed departure time; takeoff, arrival, or flight plan cancellation time; and an ATC clearance (only with prior arrangements between the ATC facility and the UNICOM licensee). UNICOM use for ATC purposes is limited strictly to these.
Is UNICOM for ATC purposes a regulatory requirement?
No. This is advisory AIM guidance describing when UNICOM service may be used for ATC purposes. It does not impose a regulatory mandate; it defines the limited, arranged circumstances under which a nongovernment UNICOM station may relay these specific ATC-related messages.