Does the helicopter take off?

Mark R

Diamond Member
Oct 9, 1999
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Lets say you have a helicopter, which is positioned on a turntable.

The turntable is set up so that it monitors the speed of the helicopter's rotor, and matches its speed so that there is no net motion.

Does the helicopter take off?
 

SoulAssassin

Diamond Member
Feb 1, 2001
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You didn't clarify if the blades and the turntable are rotating in the same direction or not.
 

Demon-Xanth

Lifer
Feb 15, 2000
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Assuming the helicopter's body has no aerodynamic effect, no because the blades have 0 wind speed.
 

mordantmonkey

Diamond Member
Dec 23, 2004
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no, this is completely different than the airplane question. the helicopter wouldn't take off if there was no net motion of the blades.
the rear rotor would only help the turntable to spin opposite the blades.
 

sswingle

Diamond Member
Mar 2, 2000
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Originally posted by: swtethan
Yes, the tail blade has a gyro which compensates for the rotation of the main blade.

And how is a tail blade (remember they are mounted sideways) going to provide VERTICAL lift?
 

SoulAssassin

Diamond Member
Feb 1, 2001
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Only if it was this cause that helo can do any friggin thing. :)

The helicopter would have to be perfectly centered in the middle otherwise it would slide outward. Also, this would be either be one helluva ride or a quick way to make the pilot puke.
 

swtethan

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Aug 5, 2005
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Originally posted by: ScottSwingleComputers
Originally posted by: swtethan
Yes, the tail blade has a gyro which compensates for the rotation of the main blade.

And how is a tail blade (remember they are mounted sideways) going to provide VERTICAL lift?

Thats not what will make it lift, it will just make the helicopter steady and pointed in one direction. The tailblade is what makes a helicopter go straight when flying, not spinning out of control. Any spinning movement detected from the gyro inside the helicopter, the computer will compensate for the spin using the tail blade.
 

Specop 007

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Jan 31, 2005
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I believe it would. The rotors would have no net speed in relation to the body of the helicopter, but they would have a net speed in relation to the ground and as such to the air around the helicopter. As long as you have air passing over the rotor blades you have lift, regardless of the body of the helicopter.
 
Jan 18, 2001
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The Helicopter would fly off from the centrifugal force and smash into the scientists' monitoring station. A great fireball explosion would ensue and all data would be destroyed.
 

2Xtreme21

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Jun 13, 2004
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Considering helicopter blades rotate anywhere between 500 and 1000 RPM, you're gonna have a hella hard time keeping a pilot conscious in there, let alone being able to control it.

Edit: Yeah and in order for this to work you're going to need the helicopter attached to the platform in some way or somehow make the platform bowl-shaped to prevent it from flying outward.
 

SoulAssassin

Diamond Member
Feb 1, 2001
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Originally posted by: swtethan
Originally posted by: ScottSwingleComputers
Originally posted by: swtethan
Yes, the tail blade has a gyro which compensates for the rotation of the main blade.

And how is a tail blade (remember they are mounted sideways) going to provide VERTICAL lift?

Thats not what will make it lift, it will just make the helicopter steady and pointed in one direction. The tailblade is what makes a helicopter go straight when flying, not spinning out of control. Any spinning movement detected from the gyro inside the helicopter, the computer will compensate for the spin using the tail blade.

If, and this wasn't clarified in the OP, say the turntable was spinning and you were able to use the tail rotor to compensate for the rotation of the turntable to keep the helo in one place effectively you could take off but, again, this was not necessarily allowed in the OP.
 

sswingle

Diamond Member
Mar 2, 2000
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Originally posted by: Specop 007
I believe it would. The rotors would have no net speed in relation to the body of the helicopter, but they would have a net speed in relation to the ground and as such to the air around the helicopter. As long as you have air passing over the rotor blades you have lift, regardless of the body of the helicopter.

You got that a bit backwards.
 

jdini76

Platinum Member
Mar 16, 2001
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Regardless of the blades moving opposite or with the turntable,

I say yes, it will still take off. because the blades are still moving which in turn causes the lift on the blades. also I would imagine the tail blades are also moving.

Edit: Spelling
 

ThePresence

Elite Member
Nov 19, 2001
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Originally posted by: ScottSwingleComputers
Originally posted by: Specop 007
I believe it would. The rotors would have no net speed in relation to the body of the helicopter, but they would have a net speed in relation to the ground and as such to the air around the helicopter. As long as you have air passing over the rotor blades you have lift, regardless of the body of the helicopter.
You got that a bit backwards.
No, I think he got it right. Air passing over the blades of the rotor provide lift, regardless of what's powering the rotation, be it the turntable or the engines.
 

sswingle

Diamond Member
Mar 2, 2000
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Originally posted by: ThePresence
Originally posted by: ScottSwingleComputers
Originally posted by: Specop 007
I believe it would. The rotors would have no net speed in relation to the body of the helicopter, but they would have a net speed in relation to the ground and as such to the air around the helicopter. As long as you have air passing over the rotor blades you have lift, regardless of the body of the helicopter.
You got that a bit backwards.
No, I think he got it right. Air passing over the blades of the rotor provide lift, regardless of what's powering the rotation, be it the turntable or the engines.

But the blades would NOT be moving in relation to the air or ground. The turntable would negate the movement of the blades.