Master the Skies in 2026: Ace Your ATPL - SARON & SAMRA Practice Test!

The minimum horizontal distance required to maintain during flight over mountains in clearance area 5 is indeed 5 nautical miles (nm). This distance is established as a safety measure to ensure an adequate buffer between the aircraft and mountainous terrain, which helps in preventing potential terrain-related incidents due to unexpected altitude changes or wind conditions that could affect the aircraft’s performance.

Maintaining a 5 nm distance allows for better visibility of the terrain and provides a margin for navigation errors that may occur, especially in mountainous regions where terrain features can change abruptly and may not always be apparent on maps or radar. This standard is part of the regulatory framework designed to promote safety in aviation operations, particularly in areas with significant changes in altitude.

In summary, the rationale behind the 5 nm requirement is rooted in the need for safety and situational awareness while flying over mountainous areas, ensuring pilots have a sufficient standoff from the terrain beneath them.