Alt-BEAM Archive

Message #10459



To: beam@sgiblab.sgi.com
From: Robert Stein rastein@dakotacom.net
Date: Sat, 19 Feb 2000 08:56:17 -0700
Subject: [alt-beam] Re: solarbotics pager mtr+fan


At 02:48 AM 2/19/00 -0700, you wrote:
>At 11:38 PM 2/18/00 , Timothy Flytch wrote:
>>Only if the axels or coaxial... if you separate the blades then you do
>>not have to use counter rotating blades to counter act tork... you use
>>an offset or tilt of the blade disk to counter tork...
>
>
>I disagree. If this were true, then many twin engine aircraft wouldn't be
>going through so much effort to have props spinning in opposite
>directions. Engine torque is a (counter)useful tool to turn aircraft in
>one direction harder than the other.
>
>Just like in any other physics system, the sum of the forces must be zero;
>if there isn't an equal and opposite torque from the motors, it's going to
>come from with resistance with the surrounding air, and produce rotation
>effect.
>
>-Dave

I'll agree with Dave on this one. There are helos that do not
have a tail rotor, they are called notars a.k.a. no tail rotors. They use
channeled air from the motor through the tail of the helo and a adjustable
port. By controlling the amount of air exiting through the tail section,
they can turn or correct for the counter rotation. Trying to counter the
rotational force of a main rotor with another rotating in the same
direction is a HUGE waste of energy. You would have tilt the prop severely
to get it to be effective.
Just for fun..why do you think it is easier to have the blades
mesh any better one way than the other...Makes no sense to me. Physics
says this is nonsense

later
R

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