A helicopter is an aircraft which propulsion and suspension are ensured by a rotary wing, usually called rotor, activated by one or several engines.
Most of helicopters use only one suspension rotor and one tail rotor, some other solutions can be two inverted rotors placed on the same axis, on two converging axes, in tandem or on both sides.
The history of helicopters starts at the beginning of the 20th Century but the progress is way slower than for planes.
The intensive use of helicopters in Algeria or in Vietnam, and the development of turbomachinery are a very important step to prove its operational capacities for militaries or civilians.
Compared to fixed-wing aircrafts, the helicopter is made out of a more complex design: his maintenance demands more efforts, and the cost for an hour of flight is higher. Its capacity to take off and to land in narrow unprepared fields makes it indispensable for certain missions and functions despite its low battery life and speed.
The helicopter has a serious advantage over the plan : its capacity to hover (remaining stationary in the air) which allows it to reach places unattainable for the plane which has a fixed wing and must always use a runaway.
On the other hand, the helicopter needs a much more powerful engine in order to raise from the ground, which limits its airlift capability. What makes the interest of the helicopter are its ability to take off and to land vertically, its capacity to reach narrow places and the possibility to move slowly and in all axes (particularly laterally and backwards).
So, the helicopter has a maneuverability adapted to a certain number of specific situations.
Helicopters are submitted to the air safety and air space management regulations.
In France, an exploitation license and an Air Operator’s Certificate (AOC) (in accordance to the decrees OPS3R10 and OPS 311) are needed in order to use helicopters for public transport. The use of helicopter containing less than three passengers on its board for local flight does not request an AOC12.
THE ROBINSON R44
The Robinson R44 is a light helicopter with a Lycoming piston engine. It has 4 seats and is produced by the Robinson Helicopter Company since 1992. Over the years, this machine has established itself with new versions: R44 Raven and R44 Raven II (2006). Thanks to its reliability and performance, it became the worldwide best seller in its category (about 714 ones sold in 2008). It also exist in police version, Clipper, equipped with floats and in a version adapted to TV broadcast, the Newscopter. A new R44 costs about 500 000€.
The Lycoming six-cylinder engine has a cylinder capacity of 9000cm3. It uses 1 liter of gas per minute. The fuel used is aviation gas: “AVGAS 100LL”, which costs 1.90€/L.
The R44 is derived from a lighter version with 2 seats, commercialized a few years earlier: the Robinson R22.
Robinson Helicopter Company is an American helicopter manufacturer, created in 1973. Its headquarters are located in Torrance, California. The helicopters made by Robinson are light machines: R22 (2 seats), R44 (4 seats) equipped with a piston engine, and R66, a 5-seat turbine-powered helicopter, put into service in 2010.
With its several models, the Robinson family allowed a majority of people to reach the usally unreachable world of helicopters, while insuring a maximum safety.
Robinson Helicopter produces the R22, R44 and R66.