: Definition of Obstacle Clearance Surfaces (OCS), which act as "invisible safety nets" to protect aircraft from terrain and structures.
The document focuses on practical aircraft operations and includes: icao doc 8168 volume 3
The document outlines standardized practices that go beyond basic Standards and Recommended Practices (SARPs) to promote international uniformity. Major topics include: Aircraft Operations : Definition of Obstacle Clearance Surfaces (OCS), which
Purpose and scope