Which of the following are the three types of ground reference maneuvers?

The three types of ground reference maneuvers are indeed the rectangular course, S-turns across a road, and turns around a point. Each of these maneuvers is designed to help pilots learn to navigate and control their aircraft while considering the effects of wind and other external factors.

The rectangular course involves flying in a rectangular pattern over a defined area, allowing pilots to practice maintaining an altitude, heading, and spacing relative to the ground. This maneuver helps develop skills in lateral navigation and understanding how to compensate for wind drift.

S-turns across a road require the pilot to execute a series of curved flight paths, integrating both left and right turns while maintaining altitude. This maneuver helps pilots learn to continually adjust their flight path based on wind conditions and improve their ability to judge distances and angles while flying.

Turns around a point involve circling a specific point on the ground, requiring constant adjustments to maintain a smooth flight path. This exercise teaches pilots how to manage bank angles and wind correction angles, enhancing their skills in situational awareness and aircraft control.

These three ground reference maneuvers are fundamental to developing a pilot's skills in navigation and understanding how to fly with respect to both the aircraft's performance and the environment.