Helicopters

History >dates Where who

Since around 400 BC, The Chinese had a flying top that was used as a children's toy. The flying top was made from bamboo and used the same method of spinning wings to fly up in the air.The first practical helicopters were built by Frenchman Louis Breguet in 1935 and by German Henrich Focke in 1936.

On September 14,1939, the VS-30o,the world's first pratical helicopter, took flight at Stratford,Connecticut. Designed by Igor Sikorsky and built by the vought-Sikorsky Aircraft Division of the United Aircraft Corporation. 

Once a helicopter leaves the ground, it is acted upon by four aerodynamic forces; thrust, drag, lift and weight. Understanding how these forces work and knowing how to control them with the use of power and flight controls are essential to flight. [Figure 2-1] They are defined as follows:

• Thrust—the forward force produced by the power plant/propeller or rotor. It opposes or overcomes the force of drag. As a general rule, it acts parallel to the longitudinal axis. However, this is not always the case, as explained later.
• Drag—a rearward, retarding force caused by disruption of airflow by the wing, rotor, fuselage, and other protruding objects. Drag opposes thrust and acts rearward parallel to the relative wind.
• Weight—the combined load of the aircraft itself, the crew, the fuel, and the cargo or baggage. Weight pulls the aircraft downward because of the force of gravity. It opposes lift and acts vertically downward through the aircraft’s center of gravity (CG).
• Lift—opposes the downward force of weight, is produced by the dynamic effect of the air acting on the airfoil, and acts perpendicular to the flightpath through the center of lift.

Thrust- The forward force produced by the power plan/propeller or rotor.It opposes or overcomes the force of drag. As general rule, It acts parallel to the longitudinal axis.


We have tried to make a paper helicopter and as we did we used a long leg and a short leg they both went Anti-Clockwise, They both took around two seconds up from two metres high.