Does any one if increasing the pitch of the bottom fixed prop so that the motor stick/prop spin slower is a good idea.
Thanks!
--- In Indoor_Construction_at_yahoogroups.com, "Jeff" <janderson@...> wrote:
>
> Process is someone has to ask the question on the clarification form on-site, then a committee rules.
>
> Anyone can submit a question.
>
> Answers take a little longer.
>
> And part of the issue with on-line responses, if you are not there to see it, it could be hard to judge if held up mechanically or aerodynamically. Which, to me, makes all the difference in the world.
>
> Its also why I asked the theoretical question. Because if I can't explain what I think I'm seeing 30 ft over my head against bright lights, is my interpretation correct?
> - Is the longer flight time reasonably explainable from a purely theoretical aerodynamic sense?
> - If some one could point me to the relevant propellor equations I might be able to puzzle it out with some examples.
> - Seems like a simple question, but I may be oversimplifying. Which has lower drag?
> --Two propellors identical but opposite pitch props working together.
> -- or one of those propellors working by itself
> -- to produce the same lift (or maybe exceed the minimum lift?).
> - True for all operating conditions, or just some?
> - Because if the drag isn't lower, how can the flight be longer?
> - And is it a small or large effect?
>
> Thanks,
>
> Jeff Anderson
> Livonia, MI
>
> --- In Indoor_Construction_at_yahoogroups.com, William Gowen <wdgowen@> wrote:
> >
> > I just checked the NSO website and didn't see a clarification.
> >
> > 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
> > > > >
> > > >
> > >
> > >
> > >
> >
>
Received on Sat Apr 09 2011 - 19:26:46 CEST
This archive was generated by Yannick on Sat Dec 14 2019 - 19:13:46 CET