Rotor-wing question

"D. Andrews" wrote in message
...
Hello all,

This is my first time posting here, but I figured maybe you all could help
me out with a question that has been nagging at me for quite a while.
Forgive me if this seems like a stupid question.

Here goes:

Does a helicopter, without lateral movement, have the ability to fly down,
or does it merely stop holding itself up?

I don't know if that makes sense, but I don't know of a better way to word
the question. I would be happy to clarify if necessary, but i don't know
what to add.

I'm not sure what the question IS exactly, but let me see if I can try to
understand it.

Does a helicopter "fly" down or merely stop holding itself up?

Well if the pitch of the blades is reduced beyond the point where the blades
provide less lift than required to hold the helicopter in the air (and it's
not travelling in any direction giving translational lift), then the heli
will descend.

This isn't exactly "flying down", it's more "not being held up" as
efficiently as it was. The amount of "hold" varies with the pitch of the
blades and the power from the engine. More of both and the heli rises, less
of both and it descends. Just enough of both and it sits at a given height.
(in simple terms of course)



--
Beav

Reply to "beavis dot original at ntlworld dot com" (with the obvious
changes)

Beav wrote:
"D. Andrews" wrote in message
...
Hello all,

This is my first time posting here, but I figured maybe you all could
help
me out with a question that has been nagging at me for quite a while.
Forgive me if this seems like a stupid question.

Here goes:

Does a helicopter, without lateral movement, have the ability to fly
down,
or does it merely stop holding itself up?

I don't know if that makes sense, but I don't know of a better way to
word
the question. I would be happy to clarify if necessary, but i don't
know
what to add.

First of all there is no such thing as a stupid question! So ask away,
some of spent many years studing and what do we have to show for it?
Just a bunch of stuff filed away in our minds!

Does a helicopter, without lateral movement, have the ability to fly
down,
or does it merely stop holding itself up?

No! it does not fly down, it will hover if the lift is equal to the
weight, thus in a hover the weight is equal to lift, and any change in
lift will change the up or down movement of the airframe. With enough
collective you can continue to rise until the airframes ceiling is
reached.

I have posted an html page for you! I borrowed it from Shirosky to
answer your question, follow the link to:

http://abnops.com/How%20a%20Helicopter%20Works.htm

Also there is a neat helicopter crash video located at

http://abnops.com/links.html


Best Reguards!

Lionel