The objective of the steep turn performance maneuver is to develop the smoothness, coordination, orientation, division of attention, and control techniques necessary for the execution of maximum performance turns when the aircraft is near its performance limits. Smoothness of control use, coordination, and accuracy of execution are the important features of this maneuver.
The steep turn maneuver consists of a level turn in either direction using a bank angle between 45° to 60°. This causes an overbanking tendency during which maximum turning performance is attained and relatively high load factors are imposed. Because of the high load factors imposed, these turns should be performed at an airspeed that does not exceed the aircraft’s design maneuvering speed (VA). The principles of an ordinary steep turn apply, but as a practice maneuver the steep turns should be continued until 360° or 720° of turn have been completed. [Figure 6-19]
An aircraft’s maximum turning performance is its fastest rate of turn and its shortest radius of turn, which change with both airspeed and angle of bank. Each aircraft’s turning performance is limited by the amount of power its engine is developing, its limit load factor (structural strength), and its aerodynamic characteristics. Do not exceed the maximum bank angle limitation in the POH. For example, a maximum 60° bank angle is a limit used by many manufacturers.
The pilot should realize the tremendous additional load that is imposed on an aircraft as the bank is increased beyond 45°. During a coordinated turn with a 60° bank, a load factor of approximately 2 Gs is placed on the aircraft’s structure. Regardless of the airspeed or the type of aircraft involved, a given angle of bank in a turn during which altitude is maintained always produces the same load factor. Pilots must be aware that an additional load factor increases the stalling speed at a significant rate—stalling speed increases with the square root of the load factor. For example, a light aircraft that stalls at 40 knots in level flight stalls at nearly 57 knots in a 60° bank. The pilot’s understanding and observance of this fact is an indispensable safety precaution for the performance of all maneuvers requiring turns.
Before starting the steep turn, the pilot should ensure that the area is clear of other air traffic since the rate of turn is quite rapid. After establishing the manufacturer’s recommended entry speed or the design maneuvering speed, the aircraft should be smoothly rolled into a selected bank angle between 45° to 60° and the throttle increased to maintain level flight. Always perfect the steep turn at 45° and slowly work up to higher bank angles. As the turn is being established, control bar forward pressure should be smoothly increased to increase the angle of attack. This provides the additional wing lift required to compensate for the increasing load factor.
After the selected bank angle has been reached, the pilot finds that considerable force is required on the control bar and increased throttle is required to hold the aircraft in level flight—to maintain altitude. Because of this increase in the force applied to the control bar, the load factor increases rapidly as the bank is increased. Additional control bar forward pressure increases the angle of attack, which results in an increase in drag. Consequently, power must be added to maintain the entry altitude and airspeed.
During the turn, the pilot should not stare at any one object. Maintaining altitude, as well as orientation, requires an awareness of the relative position of the forward tube and the horizon. The pilot must also be looking for other aircraft mainly towards the direction of the turn while glancing at the instruments to make sure the airspeed and altitude are being maintained. If the altitude begins to increase or decrease a power adjustment may be necessary to maintain the altitude if the bank angle and speed are maintained. All bank angle changes should be done with coordinated use of pitch and throttle control.
The rollout from the turn should be timed so that the wings reach level flight when the aircraft is exactly on the heading from which the maneuver was started. While the recovery is being made, forward bar pressure is gradually released and power reduced, as necessary, to maintain the altitude and airspeed.
Common errors in the performance of steep turns are:
- Failure to adequately clear the area.
- Excessive pitch change during entry or recovery.
- Attempts to start recovery prematurely.
- Failure to stop the turn on a precise heading.
- Inadequate power management resulting in gaining or losing altitude.
- Inadequate airspeed control.
- Poor roll/pitch/power coordination.
- Failure to maintain constant bank angle.
- Failure to scan for other traffic before and during the maneuver.