air marker

air marker

air marker
A cross on top of the building means a hospital.
An alphanumeric or graphic symbol on the ground or building surfaces to give guidance to pilots in flight. An example of an air marker is a red cross painted on the roof of the buildings to indicate that these are hospitals.
References in periodicals archive ?
Stamp life of an air marker is a function of the number of parts to be marked, cycle time, material, the number of characters being marked, and the force of the marker.
In a process created for soft-impact air markers by Columbia Marking Tools, the marking power is developed by a hammer propelled by compressed air.