Re: SO heli's

From: Jeff <janderson_at_twmi.rr.com>
Date: Tue, 08 Mar 2011 14:07:57 -0000

From discussions on the SO list, its not so much stability as 'balance' or 'wobble' reduction. Fixed rotor on heavy stick not in line with free rotor means at least SOME wobble. Two balanced free rotors spinning on a common axis should eliminate wobble. Not sure on how important that is, but that's what has the students worried.

Jeff Anderson
Livonia, MI

--- In Indoor_Construction_at_yahoogroups.com, "spinecho" <spinecho@...> wrote:
>
>
>
> "SO helicopter designers. Some of whom seem to go out of their way to align the rotors along a common axis."
> Perhaps this is done to increase stability?
>
>
> Which rotor should have the greater pitch? The bottom fixed rotor or the top free rotor?
>
>
>
>
> --- In Indoor_Construction_at_yahoogroups.com, Bill Carney <wcarneyjx@> wrote:
> >
> > Jeff,
> > Thanks for the clarification. I don't know if this interpretation is held by
> > event supervisors but seems to held by most SO helicopter designers. Some of
> > whom seem to go out of their way to align the rotors along a common axis.
> >
> >
> > Bill C
> >
> >
> >
> >
> > ________________________________
> > From: Jeff <janderson_at_>
> > To: Indoor_Construction_at_yahoogroups.com
> > Sent: Mon, March 7, 2011 5:08:27 PM
> > Subject: [Indoor_Construction] Re: SO heli's
> >
> >
> > Uhhh, what statement in the rules dictates rotors sharing a common axis? Not
> > what I thought I wrote, nor the way I interpret it going back and re-reading.
> >
> > I think the relevant paragraph you are looking at is para 2.d. What we meant
> > was that all the blades for a single rotor must be in a common plane, not that
> > the axes for different rotors must be common. In other words, a Chinook style
> > model helicopter should be fine (don't know about competitive though).
> >
> > If we butchered the lanquage so bad that one axis is a common interpretation by
> > event supervisors, feel free to put in a clarification on the NSO site.
> >
> > Note, if folks feel this discussion is not appropriate to this forum, let me
> > know and we'll take it off line.
> >
> > Jeff Anderson
> > Livonia, MI
> >
> > --- In Indoor_Construction_at_yahoogroups.com, Bill Carney <wcarneyjx@> wrote:
> > >
> > > Neil,
> > > Â Another thing, the rules practically dictate a ceiling walker design. Since
> >
> > > the rotors have to share an axis of rotation. About the only thing else you can
> > >
> > > do is add another rotor or increase number or blades per rotor.
> > >
> > > Bill
> > >
> > >
> > >
> > >
> > > ________________________________
> > > From: Neil Dennis <wombatt_at_>
> > > To: Indoor_Construction_at_yahoogroups.com
> > > Sent: Mon, March 7, 2011 8:50:07 AM
> > > Subject: [Indoor_Construction] SO heli's
> > >
> > > Â
> > > Just wondering, isn't anyone building something other than "ceiling
> > > walkers" ?
> > >
> > > The ones I've built or worked with all had the bottom rotor fixed to the
> > > motor stick, but I think the "both rotating" is a better idea as you can
> > > let them come up to speed before launch instead of just "tossing" and
> > > hoping it starts going vertical.
> > >
> > > wombat
> > >
> >
>
Received on Tue Mar 08 2011 - 06:08:03 CET