Which imaginary surface is centered on the runway and extends 200 ft past the runway end?

• A. Primary surface
• B. Approach surface
• C. Transitional surface
• D. Horizontal surface

Answer: (A)

The main idea is about the imaginary surfaces used for evaluating obstacles around a runway. The surface that is centered on the runway and extends 200 feet beyond the runway end is the primary surface. It runs along the runway centerline and forms the immediate area directly associated with the runway itself, providing the baseline for what heights of objects near the runway might obstruct operations.

The approach surface is aligned with the approach path beyond the runway end and has a defined slope, not simply centered on the runway. The transitional surfaces are sloped connectors that link the primary surface to other surfaces, extending outward and away from the runway. The horizontal surface is a fixed plane at a specified elevation, not tied to the runway ends. So the description matches the primary surface.