Minimum Obstruction Clearance Altitude
What is minimum obstruction clearance altitude?
The Minimum Obstruction Clearance Altitude (MOCA) is the lowest published altitude between fixes on VOR airways, off-airway routes, or route segments that meets obstacle clearance requirements for the entire segment. However, it only guarantees acceptable navigation signal coverage within 22 nautical (25 statute) miles of a VOR. Think of it as the "obstacle-safe but signal-limited" altitude—lower than the MEA, but you only get reliable VOR reception when you're close to the station.
Also known as: MOCA, Minimum Obstruction Clearance Altitude
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- missed approach point