Lets talk a moment about terminology. There are many terms associated with rotary wing flight. One must become familiar with the terminology of rotorcraft before they can expect to understand the mechanics of rotary wing flight. Let's look at a few definitions. Helicopter Education, Learning
Typical two bladed main rotor system
Here are some of the component parts that make up a helicopter. While this is an example of one specific helicopter (UH-1C), not all helicopters will have all of the parts listed here. Some of this may be a bit more of the same old stuff we have just discussed, but it will show everything as it relates to everything else on the aircraft and the location of each component.
This picture illustrates how the helicopter moves when using the appropriate controls. Up and Down movements are controlled by the "Collective Control". Collectively, the entire swashplate moves upward or downward for the whole cycle of rotation.
Side to Side and Forward and Back motions are controlled by the "Cyclic Control". Inputs are induced withing the rotor system once per cycle.
Lateral control (Also called directional control or "Yaw") is achieved by using the "Foot Pedals". Inputs are induced into the anti-torque rotor (tail rotor) in a single main rotor helicopter to increase or decrease pitch in the tail rotor to act with or counter act torque from the main rotor.
While you are looking at the picture of the controls (Left side of this paragraph), I will explain how to do a normal takeoff. First, you must make sure the throttle is all the way open (For a turbine powered helicopter, advanced properly for a reciprocating engine powered helicopter). Once you have established the proper operating RPM, then you can pull up slowly on the collective. As you increase collective pitch, you need to push the left pedal (In American helicopters...right pedal for non-American models) to counteract the torque you generate by increasing pitch. (In reciprocating engined models, you will advance the throttle as you increase collective pitch). Keep pulling in pitch and depressing the pedal until the aircraft gets light on the skids. You may sense a turning motion to the left or right, if so, you may need more or less pedal to maintain heading. The cyclic will become sensitive and (depending on how the aircraft leaves the ground heels or toes of the skids last) as you continue to pull in pitch and depress the pedal, you will put in the appropriate cyclic input to level the aircraft as it leaves the ground. As the aircraft eases into the air, forward cyclic will be required to start the aircraft in a forward motion. As the aircraft advances forward, it will gain speed until about 15 knots and then the aircraft will shudder a little as you transition through ETL (Effective Translational Lift...See the unique forces page for a more in depth explanation of ETL). As you transition through ETL, the collective will need to be reduced, the pedal will need less pressure, and the cyclic will need to be forced forward to counteract the force against the front of the rotor system. Failure to push forward will result in an abrupt nose high attitude and a reduction in forward speed. After the shudder of ELT is experienced, you will see a marked gain in forward airspeed, a reduced need for pedal input and a reduced need for collective pitch as the rotor system becomes more efficient. The airspeed indicator will most likely jump from zero to 40 knots indicated airspeed and will smoothly advance as the aircraft goes faster. Now you have taken off and with a little release of foward cyclic pressure, the aircraft will establish a climb and continue to gain airspeed. At this point, the pedals are only used to trim the aircraft, and most maneuvers are accomplished by using a combination of the cyclic and collective controls. (That wasn't so hard...was it?)
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