A liftoff, or Vertical Takeoff to a Hover, is a maneuver in which the helicopter is raised vertically from the surface to a normal hovering altitude (2 to 5 feet) with a minimum of lateral or longitudinal movement.
Prior to any takeoff or maneuver, you should ensure that the area is clear of other traffic. then, head the helicopter into the wind, if possible. Place the cyclic in the neutral position, with the collective in the full down position. Increase the throttle smoothly to obtain and maintain proper RPM (Or engage the governor and allow RPM to stabilize at flight RPM), then raise the collective. Use smooth, continuous movements, coordinating the throttle to maintain proper RPM (N/A if governor equipped). As you increase the collective, and the helicopter becomes light on the skids, torque will tend to cause the nose to swing (yaw) to the right unless sufficient left antitorque pedal is used to maintain the heading. (On helicopters with a clockwise main rotor system, the yaw is to the left and right pedal must be applied).
As the helicopter becomes light on the skids, make necessary cyclic pitch control control adjustments to maintain a level attitude. When airborne, use the antitorque pedals to maintain heading and the collective to ensure a continuous vertical ascent to the normal hovering altitude. When the hovering altitude is reached, use the throttle and collective to control altitude, the cyclic to maintain a stationary hover, and the pedals to maintain heading. When a stabilized hover is achieved, check the engine instruments and note the power required to hover. You should also note the position of the cyclic. Cyclic position will vary with the wind and the amount/distribution of the load aboard the helicopter.
Excessive movement of any one flight control requires a change in the other flight controls. For example, if while hovering, you drift to one side, you naturally move the cyclic in the opposite direction. When you do this, part of the vertical thrust is diverted, resulting in a loss of altitude. to maintain altitude, you must increase the collective. That action will increases drag on the rotor blades and will slow rotor RPM. To counter that and regain RPM you will have to increase throttle. (for governor equipped heli's the governor will add for you). Due to increased throttle, you now have increased torque, and will have to counter with added pedal pressure to maintain your heading. As you can see one can easily tend to overcontrol the helicopter as you begin, however as your level of proficiency increases, problems associated with overcontrolling decrease.
Remember, keep inputs small when hovering. Overcontrolling is the student pilot's first hurdle to overcome in learning to fly the heli. Most CFI's will give you one control at a time in learning hovering, however you have to stay coordinated in lifting off and landing, for those operations you have to use all three.
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Page Last Updated on: Dec-16-2004