Flight Maneuver: Steep Power Turns

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Figure illustrates a steep power turn. The bank angle must be large enough that there is a tendency for “overbanking,” or the bank actually steepens on its own and you must use opposite aileron to prevent the bank from becoming greater. For most general-aviation aircraft, the bank angle will be somewhere around 50 to 60 degrees. You do not want to exceed the recommended bank angle due to the load factors it may impose on the plane’s structures. As the bank angle increases, the g-loads on the airplane increase. Once past 60 degrees of bank in level flight, the g-loads increase very rapidly, with the possibility of exceeding some plane’s structural capability. At 60 degrees of bank, the load is 2 g’s—twice normal weight. At 70 degrees it increases rapidly to about 3 g’s. This is very near the limitation of most general-aviation aircraft in the normal category, so you must watch your bank angle when practicing steep power turns. 

You are not using a reference point at the center of the turn and you do not need to be at pattern altitudes. In fact, until you become proficient at steep power turns you should maintain a higher altitude in case you stall the plane accidentally.

Enter the turn at or below maneuvering speed, Va, to avoid overloading the airplane’s structure. Roll smoothly into a 50- to 60-degree bank using coordinated rudder and aileron inputs. A noticeable amount of elevator backpressure will be needed to maintain a level altitude as the bank becomes steeper. This is where many pilots become uncomfortable with flying steep turns. As the bank becomes steeper and the elevator backpressure increases, so do the g-loads, as compared to normal turns. The elevator backpressure can become quite heavy, and many pilots hesitate pulling that hard. Many use rudder opposite the direction of the turn to hold the nose of the plane up and alleviate some elevator backpressure. The turn is then very uncoordinated, at a steep bank angle where the stall speed also increases, and in the perfect setup for a high-speed stall/spin situation. Use coordinated control inputs throughout the maneuver, and this potential problem can be reduced.

Once established in the turn, use slightly opposite aileron to compensate for the overbanking tendency steep turns cause. As you adjust the aileron, also adjust the rudder inputs. If the plane loses altitude and you are pulling hard on the elevator control, add more power. The maximum turning performance for a given aircraft will be reached when the radius of the turn is smallest and the rate of turn is highest. This will vary with the bank angle and airspeed of the plane. If power settings cannot be increased and the plane is descending, decrease the bank angle to hold altitude.

As the turn progresses, monitor the heading closely. Pilots have a tendency to fly past the desired rollout heading because the plane is turning so quickly. When rolling the plane back to level flight, remember to release elevator backpressure and, if necessary, reduce engine power. It is not uncommon for pilots to gain several hundred feet as they roll out of a steep power turn due to this mistake. The amount of lead necessary to roll out on heading will depend on the plane and the rate of turn, but be prepared to give a generous lead.

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