Word: rotors
(lookup in dictionary)
(lookup stats)
Dates: all
Sort By: most recent first
(reverse)
Helicopter's Handicaps. The chief trouble with a helicopter is the rotor. It enables the helicopter to rise vertically and to hover. But it wastes power (cutting the helicopter's range to a third or fourth of a comparable airplane's), and limits the helicopter to a top speed of about 140 m.p.h. There is no such limit to a convertiplane's speed-if there is some sort of propeller for times when the craft is flying like an airplane...
...most obvious method, favored by Gyrodyne, is to put a small wing and one or more propellers on a conventional helicopter. After the craft is in the air, the rotor is disconnected from the engine and the propellers take over. The rotor continues to spin, driven by the air rushing past it, like the rotor of an autogiro.* This "windmilling" supplies some lift; the wing provides the rest...
...Rotor. McDonnell will not tell what its convertiplane will be like. Sky-side gossip believes that it will have a rotor driven by some sort of jet. One possibility is small ram-jets on each blade tip to push the rotor around. Another is a central turbojet engine blowing hot gases through hollow rotor blades. The gas will escape as jets from one side of each blade tip, making the rotor spin. When the aircraft has gained enough altitude, the central engine will be used to propel it forward, supported partly by the windmilling rotor, partly by small wings...
...McDonnell, will not tell what design it is working on. Igor Sikorsky points out that convertiplanes have many serious mechanical and aerodynamic problems that have not yet been solved. He believes that only moderate increases in speed and range are likely while the hybrid aircraft still has a whirling rotor to get in the way of the airstream. For many years, Sikorsky thinks, conventional helicopters will hold the ground that they have recently won. Eventually, perhaps, a convertiplane will be perfected that can retract its rotors completely while flying as an airplane. Such a craft, free of the rotor...
...Predecessor of the practical helicopter, in vented in 1933 by Juan de la Cierva. It had a conventional propeller and a non-powered rotor that supported it by windmilling...