Definition
A standing, written agreement between adjacent air traffic control facilities or sectors that authorizes specific routine actions — such as transferring an aircraft, crossing a boundary, or using a particular altitude or route — without the controllers having to verbally coordinate each time. The procedures are documented in a Letter of Agreement (LOA) or facility directive, and apply only within the conditions defined in that agreement.
Plain English
A pre-written deal between two ATC facilities that says, 'For these specific situations, you don't need to call us — just do it.' It saves controllers from having to phone each other for every routine handoff.
Context Anchor
Seen in the Pilot/Controller Glossary and in discussions of how ATC coordinates traffic between sectors or facilities.
Derivation
Prearranged simply means 'arranged in advance.' Coordination, in ATC, means controllers working together to safely pass aircraft between sectors or facilities. So the term is exactly what it sounds like: coordination that has already been worked out ahead of time, written down, and approved.
Why Pilots Care
Reduces radio congestion and allows smoother, faster handoffs between control areas.
Intuition Check
P-ACP is not a special clearance given to the pilot. It is an ATC coordination method used behind the scenes when the required conditions are already agreed.
Example Sentence 1
The two centers used a P-ACP that allowed eastbound traffic to be handed off at FL340 without individual coordination calls.
Example Sentence 2
P-ACP enabled efficient handoff of the flight crossing from one control area into the next.