Airplane Steep Turns

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A steep turn requires an advanced sense of coordination and timing. Maintaining altitude and orientation are only two of the problems this maneuver presents. Steep turns take the aircraft to the opposite end of the performance spectrum from slow flight. However, the possibility of an accelerated stall still exists as the aircraft reaches a 50- to 60-degree bank and large doses of backpressure must be applied to help maintain altitude.

After clearing the area, set up straight-and-level flight below maneuvering speed. (Steep turns should be done at or below maneuvering speed because of the possibility of momentarily high G-loads caused by the pitch changes required to maintain altitude.) Pick a heading and altitude at which to begin the steep turn. After completing a 360-degree or 720-degree steep turn, this will be the heading and altitude at which you want to wind up. Then, begin the roll into the steep turn at a higher-than-normal rate. As the bank reaches about half the desired maximum, 25 to 30 degrees, smooth application of backpressure is initiated as the roll continues to the desired amount of bank. If your backpressure input versus bank angle is relatively close to the desired amount, altitude can then be controlled by slight changes of bank to either increase or decrease the vertical lift. At the same time, small pitch changes might be necessary to complement the bank and aid in proper coordination.

Unless you’re a master at steep turns or enjoy high G-loads and feeling centrifugal force to the point that your fillings are pulled from your upper teeth, the vertical lift component can be taken care of through small changes in bank instead of large changes in pitch. Try it. Because a steep turn usually produces about two Gs, the airspeed will decay due to the higher load factor. Power should be added as needed to help keep the airspeed up. Remember, as the bank increases, so does your stall speed. Therefore, power application during the steep turn should help decrease the chances of an accelerated stall.

The most common problem associated with steep turns is uncoordinated entry and recovery technique. Pilots entering with too little backpressure for a given bank lose effective lift due to the steep bank and enter a descending spiral. Pilots entering with too much backpressure for a steep bank find themselves in a tight, climbing turn. Proper aileron and rudder input and the correct amount of backpressure help assure a good entry into a steep turn.

To keep a steep turn coordinated, a slight amount of opposite aileron must be used to overcome the overbanking tendency as the bank reaches the 50- to 60-degree range. Do not use top rudder to correct the overbanking tendency.

Recovery from a steep turn is as with all turn recoveries, only more control pressure is required to make it come out in a coordinated fashion. Since you turn at a high rate, it takes more rudder application than normal to overcome the turn and also the adverse yaw effect of the ailerons as they are applied to reverse the bank. Also, as you proceed through the rollout, relax the backpressure to prevent a climb after the turn is completed. In other words, as you roll back to level flight, if you don’t release the backpressure you held through the maneuver, you will increase your altitude at the end and ruin a maneuver that might have been otherwise alright.

In steep turns you will find that it requires more effort to maintain altitude. Because so much of the lift is vectored to turn the aircraft, the increase in the angle of attack must be greater as compared to shallower banks. You will find in some planes that not only do the elevator inputs become fairly heavy, but also the plane may not be able to maintain altitude unless additional power is added during entry to the steep banked turn. With some planes, no matter how much power you add you will find they have a tendency to lose altitude once the bank exceeds a certain angle. You do not normally trim the airplane for turns, since they are normally done over a short time frame and elevator pressures are held for only a short period of time.

A common error during steep turns is to become uncoordinated as the bank steepens. When in a steep turn, pilots will hold rudder opposite the direction of the turn, which tends to yaw the nose of the plane up slightly. For example, in a 60-degree left bank turn, some pilots hold right rudder to help hold the nose of the airplane above the horizon. This is often a response to the heavy elevator pressure they are holding and is often an unconscious act on their part, but this places them in an uncoordinated turn.

Level flight in a steep turn induces a load factor greater than one. The wings are producing lift that exceeds that required for straight-and-level flight. The wings are flying at a higher angle of attack and behave as though the airplane is heavier. Translated, this means the airplane will stall at a higher indicated airspeed during a turn; the steeper the turn, the faster the stall will be. If the pilot has the plane in an uncoordinated steep turn when it stalls, it is quite possible the plane will enter a spin. Some pilots enjoy spins and practice them on a regular basis. But an unplanned spin from a steep turn can make for an exciting day for you and your passengers. If you are uncomfortable with the elevator pressures you must hold to maintain altitude during a steep banked turn, reduce the angle of bank to make things more controllable.

As you roll out of a steep turn you will need to remember to reduce the engine’s power setting and to reduce the backpressure on the control yoke. There is a common tendency to erroneously gain a great deal of altitude while exiting a steep turn as a result of the additional power and increased elevator backpressure.

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