Definition
An air traffic control instruction or maneuver in formation flying directing one aircraft or element to cross to the opposite side of another aircraft's flight path, ending up on the side from which the other aircraft originated. The crossing is executed at a controlled angle so that each aircraft passes through the other's track and continues on a new heading.
Plain English
A movement where two aircraft swap sides by crossing each other's paths, so each one ends up where the other one was.
Context Anchor
Seen in weather-observation discussions, especially older or manual methods for measuring cloud height.
Why Pilots Care
Allows accurate anticipation of when a navigation aid will be passed so turns, descents, or holding entries can be timed correctly.
Grounding Statement
Picture a small balloon rising into a cloud and stopping the clock when the cloud covers about half of the balloon.
Intuition Check
Do not read this as half the distance to the cloud or half the time of the observation. It means the balloon itself appears halfway into the cloud layer.
Example Sentence 1
The flight lead called a half to pass through, so the wingman crossed behind and rolled out on the opposite side.
Example Sentence 2
At the half to pass through mark the VOR indicator began to move, confirming the fix was approaching.