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FLIGHT INSTRUCTOR'S MANUAL 131

for deviations from the correct altitude. But since perfectly calm air is a rarity, the only way the pylon can be held is by constantly varying the bank or radius of turn to counteract for the effects of drift and bumps in addition to the compensations for altitude errors. This means that the pylon cannot be held in one exact spot, but it should be held in the area bounded by the wings and struts. The nearer to the exact center of this area it is held the better the eight. This must be done with perfect coordination of the controls. The nose must not go up or down, the throttle must not be used, and variations of altitude due to convection currents or slight climbs or dives must be corrected. Any tendency to redress the position of the wing relative to the pylon by use of the rudder alone must be promptly eliminated. 
The following rules will assist the student in making the proper corrections.
1. If the pylon appears to move toward the upper wing or toward the leading edge, decrease the bank slightly to retain or regain the desired position.
2. If the pylon appears to move toward the lower wing or the trailing edge, increase the bank slightly to retain or regain the desired position.
3. The more rapidly the pylon's tendency to move in any direction in sensed or observed, the less correction necessary to hold the desired position.
4. The degree of accuracy with which the pylon is held is the correct position, without slipping or skidding, gain or loss of altitude, movement of the nose, or use of the throttle, is the index of student's ability to execute this maneuver.
In order to accomplish the objective of this type of eight, the pylon must be watched constantly and the airplane flown accurately as a result of kinesthesia with visual perception not primarily devoted to it. The vision must be kept on the pylon, but the attitude of the wing tips must also be observed as well as their seeming action with reference to the pilot, as described under "Turns." This will indicate the attitude and action of the nose as well as the bank. Other senses will warn of approaching slips and skids.
The early practices of these eights should be with shallow initial banks and turns of large radius. Under such conditions events happen relatively slowly and the student will have time to estimate and correct his error of the effects of drift without being unduly hurried or spoiling his chances of regaining the desired position relative to the pylon.
It will be noted that the effects of drift on the degree of bank necessary are just opposite of the effects of eights around pylons. With eights on pylons, the initial bank must be steepened to hold the pylon in its proper relationship as the ship turns into the wind and closer the ship is to the pylon the steeper the bank will have to be to make the pylon visible in its proper position. Therefore, as the wind drifts the ship closer to the pylon, the bank will have to be increased. This will result in the pylons being off center to the windward side of the loops if the pylons which have been selected are directly cross wind.