EXERCISE 3 - EFFECTS OF CONTROLS
In this exercise you will learn the range of attitudes through which the helicopter will normally be operated and how the controls are used to achieve and maintain the desired flight attitudes. The skills learned in this exercise form the basis for all future helicopter air exercises.
Now that flight training has begun in earnest, start observing this rule: look around. For safety in flight, keep alert for other aircraft. Look out continually. Realise that there are blind spots behind and beneath your helicopter, and never assume that others have seen you. Be especially alert during nose-up attitudes of the helicopter when the blind spot enlarges due to a decrease in forward visibility.
A pilot must be constantly on the lookout for other aircraft and must keep up a continuing search of the sky. It is commonly believed that the eye sees everything in its field with equal clarity. This is not so. Fix your gaze about 5 degrees to one side of this page, and you will no longer be able to read the printed material. Studies have revealed that the eye perceives very poorly when it is in motion. Wide sweeping eye excursions are almost futile and may be a hazard, since they give the impression that large areas of sky have been examined. A series of short, regularly spaced eye movements is recommended for maximum efficiency in searching the sky.
ADJUSTING THE CONTROLS
Your instructor will demonstrate the correct adjustment of the flight controls in preparation for flight, and the correct use of the control frictions. Ensure that the pedals are adjusted so that you are sitting in a comfortable position, or you may find yourself becoming fatigued very quickly.
CYCLIC STICK
Moving the cyclic stick will tilt the rotor disc and cause the helicopter to either pitch or roll, or a combination of the two, effecting motion in the direction the cyclic is moved. Remembering that the total lift reaction is always perpendicular to the rotor disc, when the disc is tilted from the lift (vertical) component, the thrust (horizontal) component will cause the helicopter to move in the direction of rotor tilt. (See Figure 3-1). After the helicopter has been started your instructor will demonstrate how the disc reacts to cyclic control movements. Observe that the disc tilts in a direction corresponding to the direction in which you have moved the cyclic.
Figure 3-1: Total Lift Reaction
Notice that the total lift reaction is unchanged in magnitude, but the cyclic movement has changed the direction of that force, thus also affecting the attitude and airspeed of the helicopter.
Your instructor will demonstrate the effects of cyclic stick movement to maintain straight and level flight, as this is the basis for all attitude changes. To begin with, you should note the helicopter attitude by reference to the horizon, and your instructor will also point out the instrument indications in response to cyclic inputs. The cyclic stick controls the aircraft attitude and therefore the airspeed, which in turn affects altitude.
Fore and aft cyclic movement is used to achieve and maintain the desired attitude to select the airspeed. The amount and rate of attitude change varies with the amount and rate of cyclic movement. Lateral movements of the cyclic will produce and control-rolling motion to establish and maintain desired angles of bank, or to restore the helicopter to a level attitude. Once again the amount and rate of roll varies with the amount and rate of cyclic movement.
中國航空網 m.k6050.com
航空翻譯 www.aviation.cn
本文鏈接地址：直升機飛行訓練手冊 HELICOPTER FLIGHT TRAINING MANUAL(8)
