What are holding patterns used for in navigation?

Holding patterns serve a critical function in air navigation by allowing aircraft to maintain a predictable and controlled flight path while awaiting further instructions from air traffic control. Specifically, when an aircraft enters a holding pattern, it typically flies a racetrack-shaped course within a designated area, ensuring it remains within a specific airspace.

This is particularly useful when there are delays at an airport due to congestion, weather conditions, or other operational factors that prevent immediate landing. By utilizing a holding pattern, pilots can effectively manage their altitude and flight path, maintaining communication with air traffic control as they await clearance to either land or continue on their planned route.

The other options do not accurately describe the primary purpose of holding patterns. While they might influence aspects of flight like speed or fuel consumption indirectly, the essential role of holding patterns is to manage air traffic flow and maintain safety and efficiency in controlled airspace. Additionally, holding patterns are not designed for navigation using visual landmarks, as they rely on instrument navigation in radar or non-radar environments, focusing on maintaining a specific geometric flight path rather than visual cues.