So we don't get to far on AMA rules, reminder, they only inform SO rules writers and SOME event supervisors. The only binding rules for SO are the ones published by SO and have in the past specifically contradicted AMA practice, eg torque burners.
Side question on the theory behind this. How does it work?? For one rotor to hold the same weight as two it has to spin faster, increasing drag that rotors drag. Is this increase less than the loss of drag from stopping the other rotor? If not, how is efficiency (flight time) increased? If it is, then I understand the result.
Thanks,
Jeff Anderson
Livonia, MI
--- In Indoor_Construction_at_yahoogroups.com, Benjamin Saks <bensaks@...> wrote:
>
> I remember back in my youth of chasing the Junior AMA Helicopter record that
> there were old designs which used this practice to kill the top rotor spin
> and get longer flight times. I could be wrong but I think that they made
> flights like this grounds for disqualification.
>
> In order for this to work well, you need to "drill" the top rotor pylon into
> the ceiling. It works in the soft drop ceiling tile best, but I could not
> imagine anywhere else. Otherwise you would have to get lucky and lock in the
> rotor into a girder or something, assuming it would release when the power
> decreased enough.
>
> On Wed, Mar 30, 2011 at 3:17 PM, Jeff <janderson_at_...> wrote:
>
> >
> >
> > Tom has it right, this is NOT the place for official clarifications, those
> > are only posted on the NSO website so they are available to all.
> >
> > Also, I'm only one voice in these decisions, several others contributed to
> > the final, published rules and they all get a voice in coming up with the
> > official answers.
> >
> > I can however quote the relevant portion of rule, 3.k "...Time Aloft ...
> > stops when ... the rotors no longer support the weight of the helicopter..."
> >
> > While the answer seems clear to me from that, I wrote it, thus the need for
> > an official clarification. Especially since I'm supervising Robot Arm this
> > year, not Helicopters, at the national contest.
> >
> >
> > --- In Indoor_Construction_at_yahoogroups.com, "Thomas" <parkreation@>
> > wrote:
> > >
> > > Not to dodge this issue, but this needs to be addressed first through SO
> > Clarifications before a statement may be published. Even still, I would
> > rather yield to Jeff A. on this anyway as this event is his creation. let me
> > see what else I can uncover...
> > >
> > > Regards,
> > > Tom Sanders
> > > SO National Supr (Wright Stuff)
> > >
> > > --- In Indoor_Construction_at_yahoogroups.com, "Bill Gowen" <wdgowen@>
> > wrote:
> > > >
> > > > I'd be interested in hearing from Tom and Jeff on this subject.
> > > >
> > > > ----- Original Message -----
> > > > From: abcd4321
> > > > To: Indoor_Construction_at_yahoogroups.com
> > > > Sent: Tuesday, March 29, 2011 6:16 PM
> > > > Subject: [Indoor_Construction] SO Helicopter
> > > >
> > > >
> > > >
> > > > Hi, my team recently won the NJ state Science Olympiad Tournament so we
> > are going to nationals. We had a 2:12 helicopter flight wHich got us second
> > place. I recently found out that it is possible to get much higher times if
> > the top (free) rotor stops spinning once the copter reaches the ceiling and
> > starts to spin again once the copter starts to come down. However Locking
> > the rotor does not work as the motor stick still needs to spin. Essentially
> > he rotor must get stuck to the ceiling under the lift generated solely by
> > the lower rotor. We tried to just use tape which worked until it got stuck
> > to tightly.
> > > >
> > > > I was hoping you guys could help out.
> > > >
> > > > Thanks,
> > > > Sarath Jaladi
> > > >
> > >
> >
> >
> >
>
>
>
> --
> BEN SAKS
> www.bensaks.com
>
Received on Wed Mar 30 2011 - 12:34:51 CEST
This archive was generated by Yannick on Sat Dec 14 2019 - 19:13:46 CET