What are S-Turns?
S-Turns are typically performed over a long straight road and give you another opportunity to hone in on your skills in controlling the airplane in relation to the ground at low altitudes.
The idea behind the S-turn maneuver is for you to vary your angle of bank to control your drift from the wind, allowing you to inscribe perfect half circles on either side of the road you are using.
The purpose of S-Turns is to:
- Maintain a specific relationship between the airplane and the ground.
- Divide your attention between the flight path, ground-based references, manipulation of the flight controls, scanning outside for hazards, and glancing in at aircraft instrumentation as necessary.
- Scan the ground below you for straight-line references which are long enough to use for S-Turns. This could be a road, railroad track, or a power line to list a few examples. Try to find a line that is perpendicular to the winds. This will make the maneuver easier.
- As this maneuver is performed at a low altitude, ensure that are good landing options nearby such as a large open field.
- As with any maneuver, clear the area by use of clearing turns before entering the maneuver.
Performing the Maneuver:
- Fly away from the road and come back in to enter the maneuver on the downwind (wind on your tail, just like a turn about a point)
- Always cross the road with your wings level and the airplane perpendicular to the road. (don’t start to bank the opposite direction until you have crossed the road)
- Adjust the bank angle as necessary to correct for groundspeed changes and maintain constant radius turns.
- Dependent on the wind, ground speed will vary. Use steeper bank angles when at higher ground speeds, and more shallow bank angles when at slower ground speeds.
- Maintain the proper wind-correction angle to maintain the desired ground track.
Some common checkride errors for this maneuver are:
- Not adequately clearing the area (you must perform clearing turns prior to beginning any maneuver. Look above, below, and on either side of the airplane for any safety hazards such as obstacles or other traffic).
- Not being straight-and-level prior to entering the maneuver. Give yourself space to enter the maneuver.
- Failure to maintain altitude throughout the maneuver (climbing or descending).
- Not properly identifying the wind direction.
- Not properly executing constant radius turns.
- Not using smooth flight control inputs.
- Not establishing the appropriate wind correction angle.
- Not applying coordinated aileron and rudder pressure, resulting in the airplane skipping or slipping.