MOCAs ensure navigational signal coverage within which distance from a VOR?

Minimum Obstacle Clearance Altitudes (MOCAs) are designed to provide safe vertical clearance above obstacles while also ensuring navigational signal coverage. Specifically, when discussing MOCAs in relation to VOR (VHF Omnidirectional Range) stations, they are established to guarantee that aircraft maintain a reliable signal while flying at these altitudes.

The correct distance from a VOR for MOCAs is 25 statute miles (SM), which converts to approximately 22 nautical miles (NM). This range allows for the aircraft to receive consistent navigational signals, which is crucial for safe flight operations, particularly in areas where terrain may vary significantly.

The other options suggest different distances that do not correctly represent the established standard for MOCAs in proximity to a VOR. By using the correct distance, controllers and pilots can ensure compliance with safety regulations and maintain communication and navigation integrity during flight.