What does MOCA stand for?

Minimum Obstruction Clearance Altitude refers to the lowest altitude that provides a required clearance from obstacles in the area. It is a crucial concept in aviation navigation and safety, as it ensures that aircraft will be above any obstructions, like mountains or buildings, when flying in certain airspace, especially in mountainous regions. This altitude is designed to guarantee adequate terrain clearance during flight, allowing pilots to navigate safely and avoid collisions with physical barriers.

Furthermore, MOCA is particularly important when considering instrument flight rules (IFR) operations, whereby pilots rely on instruments for navigation and must have assurance that they are safely above any obstructions in their flight path. It is also used by air traffic control for navigation purposes, helping ensure that aircraft can safely traverse through various environments.

The other options, while they contain similar terminology, do not convey the correct meaning associated with safe altitude operation in relation to surrounding obstacles. For example, "Maximum Obstruction Clearance Altitude" is not an established term in aviation, and the other terms do not accurately define the necessary altitude for obstacle avoidance.