Which statement best defines minimum obstruction clearance altitude (MOCA)?

• A. The lowest altitude to maintain obstacle clearance for the entire route segment and ensures navigation signal coverage within 25 miles of a VOR.
• B. The minimum altitude for cross-country flight.
• C. The altitude you must maintain to stay in VOR reception.
• D. The highest altitude allowed on a route segment.

Answer: (A)

MOCA represents the minimum altitude that provides obstacle clearance along the entire route segment, with the added detail that you will also have VOR navigation reception within 25 nautical miles of the VOR. In other words, if you fly at MOCA, you’re protected from obstacles for the whole leg, and you can rely on the VOR signal as long as you’re within 25 NM of that VOR. Outside that 25 NM range, the VOR reception isn’t guaranteed, even though the altitude still serves obstacle clearance along the route. This is why the statement that MOCA is the lowest altitude to maintain obstacle clearance for the entire segment and to ensure navigation signal coverage within 25 miles of a VOR best captures what MOCA represents.