How helicopters get off the ground and how they are controlled while in flight.
Fort Worth, TX (WiredPRNews.com)—Helicopters have revolutionized aviation because they can do things like hover in place, fly backwards and rotate in place that fixed-aircraft cannot do. This makes them ideal for military and emergency operations where hovering and precise maneuvers are essential.
The main horizontal rotor lifts the aircraft and provides directional power when the aircraft tilts in a particular direction. According to the website How Stuff Works, the aircraft’s ability to tilt is rooted in the hub of the main rotor in a mechanical assembly known as a ‘swash plate.’ This mechanism, according to the website, allows the pilot to adjust the angle of the horizontally-spinning rotor blades, which tilts the aircraft in the desired direction.
The angle at which the rotors spin, called the angle of attack, helps determine how quickly the helicopter lifts into the air. The steeper the angle of attack, the faster the helicopter rises in altitude, according to How Stuff Works.com.
Some helicopters, such as air ambulances and certain military choppers, use jet turbines to help with forward motion if they have to cover long distances.
The tail rotor is what keeps the helicopter from spinning uncontrollably and helps the pilot steer the aircraft while in flight. The technical name for this is the ‘anti-torque rotor’ because it counteracts the twisting (torque) motion of the rotating horizontal lift rotor blades.
However, some helicopters don’t have vertical tail rotor, but use a counter-rotating horizontal rotor to deliver the anti-torque function. The most common version of this kind of anti-torque rotor is the Chinook military transport helicopter.
For a realistic example of how helicopters work, check out the working toy helicopters at any nearby RadioShack. You can also see video explanations of helicopter movements at Howstuffworks.com.