Aircraft ceiling

From Glossary of Meteorology

aircraft ceiling

  1. After U.S. weather observing practice, the ceiling classification applied when the reported ceiling value has been determined by a pilot while in flight within one and one-half nautical miles of any runway of the airport.

    Aircraft ceilings may refer to vertical visibility or obscuring phenomena aloft as well as to clouds, and are designated A in aviation weather observations.

  2. The maximum altitude at which any given aircraft can be operated safely.