MOCA stands for which altitude concept?

• A. Missed Obstacle Clearance Altitude
• B. Minimum Obstruction Clearance Altitude
• C. Maximum Obstruction Clearance Altitude
• D. Minimum Operational Clearance Altitude

Answer: (B)

MOCA, or Minimum Obstruction Clearance Altitude, is the lowest published altitude on enroute charts between navigation aids that guarantees at least 1,000 feet of obstacle clearance along the route (2,000 feet in mountainous terrain). This altitude provides a safety floor to prevent hitting obstacles while flying the segment between VORs. It also ensures you can receive the VOR signal within 22 nautical miles of the station, which helps with navigation on that leg. Beyond 22 NM from the VOR, you can’t rely on MOCA’s signal guarantee, though you still must meet the obstacle clearance requirement. The other terms aren’t standard designations for this concept, so they don’t describe what MOCA actually represents.