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Old 07-07-2009, 05:11 PM   #24 (permalink)
joediamond
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Quote:
Originally Posted by Finless View Post
OK so that makes sense now. Is it that they CANT do vertical and if not why? If they had negative available then I don't see why not?

Then I have to ask what happens in a real heli if you are in a 900 foot hover and the engine quits? To get forward momentum you would have to use energy from the rotor and change the angle of attach of the rotor to forward. In doing so wont you dump head speed without having negative to compensate?

Bob
A real heli can auto vertically but the rate of descent would be extremely high. Most height/velocity graphs allow for a stationary hover above 400 AGL. From that height you have enough altitude to build up enough forward speed for a normal auto. From a low hover there is enough stored energy in the rotor to cushion the landing. A medium altitude hover is bad, not enough altitude to build forward speed and not enough energy in the rotor to get the machine down.
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