Our heavyweight helicopter equal in the world does not have
In Rostov started production of the most load-lifting rotary-wing car The Russian holding «Helicopt[...]
The autogyro
The autogyro differs from the helicopter in that the rotor blades are not driven directly by an engine. A conventional aircraft propulsion system, such as an engine and propeller, is used to propel the aircraft forwards. Unlike the helicopter, the rotor axis is tilted backwards during flight, and the blades are
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Fig. 1.31 An ultra-light autogyro A two-bladed teetering rotor is used. The motor drives a pusher propeller and can also be used to give the rotor an initial spin-up via a belt drive |
blown round by the relative air flow. As they ‘autorotate’, they generate lift, like the blades of a helicopter.
The autogyro requires a certain amount of forward speed in order to maintain sufficient autorotation to lift the aircraft. Thus, although it has the advantage of being able to fly very slowly and make a short vertical final descent, it can not hover or take off vertically. Although mainly of historical interest, there has been some renewed interest in the autogyro for recreational flying, as illustrated by the example shown in Fig. 1.31.
As on the helicopter, the blades of an autogyro are normally free to flap up and down. In flight, the difference in the relative velocity between the advancing and retreating sides again tends to cause the blades to flap up towards the front and down towards the rear, thus tilting the axis of blade rotation rearwards. For an autogyro, this rearward tilt presents no problem, as the forward thrust is provided by a separate propeller. Rearward tilt is in fact necessary to sustain the rotor rotation. As the blades are hinged freely to the hub, they cannot produce a strong rolling moment, and for an autogyro, cyclic pitch control is not essential.
