Airplane Maneuver: Turns About a Point

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Turns about a point, as well as all ground track maneuvers, are entered downwind. The primary reason for the downwind entry is safety. Because the angle of bank is proportional to the ground speed, the faster the ground speed, the steeper the bank. The slower the ground speed, the shallower the bank. Therefore, if the turn about a point is entered downwind, the initial bank will be the steepest encountered in the maneuver. It prevents a pilot from making the mistake of entering the maneuver upwind (into the wind) at a steep bank, only to find that to hold the desired radius, the bank must be increased to a point that might exceed the capabilities of the pilot or the aircraft.

All ground track maneuvers incorporate an infinite number of bankangles, but the three most used reference banks are shallow, medium, and steep. Once you have mastered the basic rules of bank as they apply to ground track, you should have no difficulty with any ground track maneuver. The basic rules of bank are:
• Steep bank downwind (wind behind you).
• Shallow bank upwind (wind in front of you).
• Medium bank crosswind (wind from your side).

Remember that the wingtips point at the reference point only when you are directly upwind or downwind. Everywhere else your wingtips will be either ahead of or behind the reference point. Don’t try to keep the wingtips on the point or you will make a very eggshaped circle. Crabbing is important at all times, not just directly upwind or downwind.

The turn about a point can be a very large or very small circle. It all depends on how close you are to the reference point. The closer the aircraft is to the reference point, the steeper the banks will be, and the smaller the circle. The farther away from the reference point the aircraft is, the shallower the bank, and the larger the circle. And remember, banks are relative. Certainly a 45-degree bank is steeper than one of 15 degrees, but it is only three times as steep, whereas a bank of five degrees is five times as steep as a bank of one degree. So think of your angle of bank as one relates to the other, not in terms of 45, 15, 10 degrees, etc. Think of them as shallow, medium, and steep.

To properly execute a turn about a point, you first need to attain the proper altitude. The FAA recommends you be from 600 feet to 1000 feet above any obstacles as you choose a point about which to pivot. Make sure the point is stationary. I once had a student try to do a turn about a point around a car. And the car was going about 60 MPH down the road—truly an advanced maneuver for which the student was not ready.

As you enter downwind and cross abeam of the point, the bank will be initiated. It should be a coordinated turn resulting in a steep bank. The steep bank will be made progressively shallower through the first half of the circle. As the crosswind point is reached, the bank will be medium, and it will also be the point of maximum crab angle since you will be directly crosswind. As the aircraft proceeds from the crosswind to the upwind position, the bank will get progressively shallower until you arrive at the upwind position with the shallowest bank of the entire maneuver. You now have turned 180 degrees. At this point, the entire banking procedure reverses and gets progressively steeper as you go from upwind to crosswind. Proceeding from crosswind, the bank continues to steepen until you arrive at the downwind starting point and again have the steepest bank of the maneuver.

If there is no wind, theoretically, the bank will be constant throughout the 360-degree turn. Therefore, it is probably best to practice this maneuver in a steady breeze. A gusty wind condition can cause you some difficulty in acquiring a feel for changes in ground speed and resultant banks required to form a constant radius about the point. Remember to strive to hold a constant altitude throughout the maneuver.

And do not become so engrossed in your maneuver that you forget to look out for other aircraft. I remember flying at 6000 feet giving some aerobatic training and looking down to see what I at first thought was two students dogfighting. They were far below us, in unison, going around a circle in perfect symmetry. As I watched them for a minute, it began to dawn on me that they were, in fact, both doing turns-around-a-point around the same point! And they never saw each other! Imagine the potential for tragedy. I quickly called one of the aircraft on the radio and instructed them to break to the right since they were in effect flying in formation without the benefit of seeing the other aircraft.

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