Pre-Solo Training Program Flight Briefing: Lesson 9 Ground Reference Maneuvers In cooperation with Mid Island Air Service, Inc. Brookhaven, NY (Michael Bellenir, CFI)

Lesson 9 Objectives During this briefing, you will learn how to perform ground reference maneuvers. These maneuvers will increase your understanding of wind correction, develop your ability to multi-task, and develop your flying skills. Upon completion of this briefing, you will practice flying a rectangular course, turns around a point, and S-turns, demonstrating proper wind correction techniques.

Effect of Wind on Ground Track We’ve already seen that wind can have an affect on the airplane’s track over the ground.

Turning Radius Airplane speed affects its ability to turn. A faster speed requires more distance to accomplish a turn than a lower speed. Because wind affects the groundspeed of the airplane, it also affects the radius of turns over the ground.

Turning Radius

Wind Correction To fly the airplane relative to fixed points on the ground you must correct for winds. Ground reference maneuvers develop your skill to correct for drift and varying turn radius caused by the wind. Three specific maneuvers have been developed to develop and test your knowledge and skill of wind correction techniques. Rectangular course Turns around a point S-Turns

Rectangular Course Objective: to fly a course that results in the ground track being shaped like a rectangle. The wind component is different on each leg and must be properly corrected for. Used in the traffic pattern; runway is the reference on the ground.

Rectangular Course

Turns Around a Point Objective: To fly a turn with a constant radius relative to a fixed point on the ground. The wind component will be constantly changing, affecting the radius of the turn relative to the point on the ground. To compensate for changes in turn radius, the bank angle will need constant adjustment throughout the maneuver.

Turns Around a Point

S-Turns Objective: To fly two identical half circles along a straight line on the ground and arrive at specific headings over specific points. The wind component will be constantly changing, requiring changes in bank angle to maintain the desired track. The turn rate must be adjusted to arrive at certain headings over certain points during the maneuver.

S-Turns

Flying Ground Reference Maneuvers To fly a ground reference maneuver successfully, it is important to pick a ground reference point that is suitable and appropriate. Rectangular Course: At least one straight line or rectangle pattern on the ground (farm field, intersection of roads, etc.). Turns Around a Point: One small but easily visible point, viewable from all directions. S-Turns: A long, straight line oriented perpendicular to the wind direction.

Reference Point Selection These maneuvers are performed low to the ground. When picking a reference point, keep in mind the following factors: Avoid selecting a point near high terrain or obstructions. Avoid selecting a point over a congested area. Be considerate of people on the ground. Be mindful of surrounding airspace and air traffic. Select an area that provides a suitable emergency landing area within gliding distance. Pick points that don’t move. In perfectly calm conditions, a point moving at a steady speed and direction could simulate wind, but using moving points for reference generally defeats the purpose of the maneuver.

Flying Ground Reference Maneuvers You must divide your attention appropriately between monitoring your ground track, maintaining your altitude and airspeed, maintaining your awareness of your position, and effect of wind, all while looking for other traffic. Priority One: Keep airplane under control Priority Two: Maintain separation from other aircraft. Priority Three: Fly the maneuver Enter the maneuver downwind (with tailwind-highest ground speed). This will allow you to make your steeper banks first (while altitude and airspeed are under best control), and get a feel for the wind strength. Avoid staying over one location for extensive periods of time. Don’t annoy people on the ground any more than necessary.

Review Questions How do you correct for a crosswind when flying a rectangular course? How do bank and groundspeed vary when turning into a headwind? What flight operation do ground reference maneuvers prepare you for? What are the considerations in choosing a reference point for ground reference maneuvers? Where should you enter a ground reference maneuver? Why? Write down your answers before continuing to next slide

Review Answers How do you correct for a crosswind when flying a rectangular course? Turn the nose of the plane slightly into the wind, to track straight. How do bank and groundspeed vary when turning into a headwind? Both decrease. What flight operation do ground reference maneuvers prepare you for? Flying the traffic pattern. What are the considerations in choosing a reference point for ground reference maneuvers? Avoid high terrain, obstructions, congested areas; be mindful of airspace and traffic; choose an emergency landing area within gliding range; pick points that do not move. Where should you enter a ground reference maneuver? Why? Enter downwind. Gives you maximum bank and groundspeed at start of maneuver, to get a feel for winds. Review any missed questions before continuing to today’s flight.

On Today’s Flight Be as precise as possible while en-route to the practice area, hold altitudes and headings exactly. Be smooth, maintain coordination and positive airplane control. Maintain orientation and track with ground reference points. If you get too far away, turn steeper to get back on course If you are too close, turn shallower or level off to get back on course.

Today in the Pattern Wind correct the pattern legs properly and also wind correct the turns. Shallower turn with headwind Steeper turn with tailwind Keep in mind the wind direction at all times. Thanks to Mid Island Air Service, Inc. Brookhaven, NY (Michael Bellenir, CFI)