S-Turns Airplane Maneuver

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The S-turn is a fine training maneuver, requiring the same bank techniques incorporated in the turn about a point. The S-turn differs from the turn about a point in that instead of flying a complete 360-degree circle, you make a series of 180-degree turns along a road or other straight landmark. Once again, crab angle, along with shallow, medium, and steep banks, are your primary guides in obtaining the desired track over the ground.

Begin at about 600 feet above obstructions and over a road that lies perpendicular to the wind. Enter downwind for the same reasons mentioned for the turn about a point. As you approach the road, decide how large you intend the half circles to be. Remember, the points of maximum distance from the road should be equidistant on both sides of the road—this helps maintain the symmetry of the maneuver.

The S-turn maneuver begins when the aircraft is directly over the road. At this point the bank is initiated and is your steepest bank because the ground speed is the fastest here. As the aircraft continues to the crosswind point, the bank gradually shallows to become medium and you encounter the maximum crab angle. Turning to upwind, the bank gradually decreases to the most shallow as the aircraft reaches the 180-degree point. It occurs just as the aircraft reaches the road, with the aircraft exactly perpendicular to the road.

The bank is reversed for the turn in the opposite direction. The aircraft is still upwind, so the shallow bank should be held until the aircraft turns far enough to cause you to gradually steepen the bank when you arrive at the crosswind point, with medium bank and maximum crab angle. From crosswind, continue to steepen the bank gradually until you arrive back over the road with the steepest bank for this half of the maneuver. You should arrive back over the road just as you complete the 180-degree turn, not before or after. The two half circles just completed form one complete S-turn.

Of course, you don’t have to stop with just one S-turn. In fact, it’s probably better practice to put together several in one direction and then reverse your course and go back down the road in the opposite direction. Be cautious and don’t become so engrossed that you forget to watch for other aircraft. Seldom are you as alone as you think you are. In fact, given the scope and area of the sky, it is amazing how many midair collisions and near misses we have in the United States each year.

The S-turn may be made any size the pilot desires. The only thing governing the size of the half circles is your initial bank. The steeper the initial bank, the smaller the circle. The shallower the initial bank, the larger the circle. The symmetry of the S-turn is kept uniform by going twice as far down the road as you go out from the road. This symmetry ensures a perfect half circle.

The list of common errors in the execution of an S-turn would be headed by the pilot hurrying the turn from upwind. At this point, the ground speed is the slowest and there is a tendency not to hold the shallow bank long enough for the aircraft to fly away from the road as far as it was on the downwind side. The best way to overcome this is to pick reference points of equal distance from both sides of the road and then, without cutting corners, fly to them.

Crossing the road before or after the maneuver is completed is another common error. The aircraft should cross the road just as the 180-degree turn is completed and roll into a turn in the opposite direction. Since most of the time you will be flying with your head out of the cockpit for visual reference, a brief glance at the altimeter every so often confirms any altitude change you might not be aware of.

The S-turn is one of the better coordination exercises because you have to use visual as well as instrument reference, feel for the aircraft, and all your senses, with the possible exception of taste and smell. While you are doing all this turning from one direction to the other, always remember to watch for the other aircraft as well as monitor headings, altitude, airspeed, and bank. This constant monitoring helps improve the ability to think and act quickly and accurately. When taken seriously, the S-turn is a very exacting and demanding maneuver worth perfecting.

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