What does OROCA provide within each quadrangle on a chart?

OROCA, or Off Route Obstruction Clearance Altitude, is designed to provide a minimum altitude that ensures clearance from obstacles within a designated quadrangle on a chart. This altitude is crucial for pilots flying at altitudes lower than those shown on standard route charts, as it helps to ensure safe navigation by providing a buffer above known obstructions such as terrain and man-made structures.

By maintaining altitude at or above the OROCA value, pilots can be confident that they are avoiding potential collisions with obstacles, allowing for safer flight operations, especially in areas where they are not following designated airways. This makes obstruction clearance the primary purpose of OROCA, which is essential for navigating safely through varied terrain or unfamiliar areas.