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Re: Duration

Posted: December 13th, 2011, 8:42 pm
by lucwilder42
Small town schools can win, it all depends on the kids

Leftover Winds

Posted: December 19th, 2011, 3:54 pm
by Orange714
I'm not really sure where to post it, but how drastically would leftover winds affect the overall duration time?
Also, how do you decrease the number of leftover winds? Because out first helicopter has a lot left over when it hits the ground.

Thanks!
PS I'm very new to helicopters so any help at all would be appreciated!

Re: Leftover Winds

Posted: December 19th, 2011, 5:47 pm
by mrsteven
Orange714 wrote:I'm not really sure where to post it, but how drastically would leftover winds affect the overall duration time?
Also, how do you decrease the number of leftover winds? Because out first helicopter has a lot left over when it hits the ground.

Thanks!
PS I'm very new to helicopters so any help at all would be appreciated!
Leftover winds is a sign that the helicopter isn't as effective as it could be. The more, the less time (obviously).

You can change the pitch of the rotors, which is hard, or change the amount/width of said motors (AKA rubber).
I would recommend changing the amount/width of the rubber so you do not have to continue remaking helicopters with slightly different pitches simply to find the right pitch for that rubber. Changing the rubber to match the rotor is easier and less time consuming.

Re: Leftover Winds

Posted: December 19th, 2011, 9:19 pm
by chalker7
Orange714 wrote:I'm not really sure where to post it, but how drastically would leftover winds affect the overall duration time?
Also, how do you decrease the number of leftover winds? Because out first helicopter has a lot left over when it hits the ground.

Thanks!
PS I'm very new to helicopters so any help at all would be appreciated!
mrsteven had a good response above, but we also had an extensive discussion about this topic last year. I would read the posts from the rubber thread, in particular this section: http://www.scioly.org/phpBB3/viewtopic. ... &start=300 to understand a little more about what is going on.

It all comes down to the number of useful turns on your rubber band (those that are keeping the helicopter in the air). If you are landing with a lot of winds, I would just make a shorter rubber band. It won't hold as many winds, but will wind to the same torque as the longer one (presuming the cross-section is the same) and will weigh less (which means your rotors have to lift less overall mass in the air).

The lack of restrictions on rubber band mass within the rules this year is intended for everyone to play around with different length motors and see what cutting or adding rubber band mass to your helicopter does to flight time.

Re: Duration

Posted: December 28th, 2011, 5:00 pm
by illusionist
Just curious, since the point of limiting the rotor dimensions and rubber mass in previous years was to limit flight times (more practical for tournament purposes), why are they altered this year when they'll result in longer flight times?
I'm not complaining or anything, just wondering.

Re: Duration

Posted: December 28th, 2011, 5:18 pm
by chalker7
illusionist wrote:Just curious, since the point of limiting the rotor dimensions and rubber mass in previous years was to limit flight times (more practical for tournament purposes), why are they altered this year when they'll result in longer flight times?
I'm not complaining or anything, just wondering.
The rubber mass restriction in airplane events was definitely low enough to be restrictive, but I am not certain it was restricting flight times in helicopters last year. In fact, I suspect using ~1.5g was better than 2g (as to lower the overall flying mass of the helicopter). The intention of removing the restriction was to sort of throw the rule out to the free market and let you all experiment to find the best mass.

The adjustment of the major dimensions is more to force teams to build new models and prevent hand-me-down devices from graduating students. We balance the critical dimensions to try and keep flight times manageable. I did some tests over the summer and think the top teams will still be within manageable flight times for competition. The last couple of years in Wright Stuff we had the occasional 5+ minute flight and still ran the tournaments without issue.

Re: Duration

Posted: December 28th, 2011, 7:39 pm
by lucwilder42
chalker7 wrote: I did some tests over the summer and think the top teams will still be within manageable flight times for competition. The last couple of years in Wright Stuff we had the occasional 5+ minute flight and still ran the tournaments without issue.
So are you hinting that you had some 5+ minute flight times during your summer testing? :)

Re: Duration

Posted: December 28th, 2011, 7:44 pm
by chalker7
lucwilder42 wrote:
chalker7 wrote: I did some tests over the summer and think the top teams will still be within manageable flight times for competition. The last couple of years in Wright Stuff we had the occasional 5+ minute flight and still ran the tournaments without issue.
So are you hinting that you had some 5+ minute flight times during your summer testing? :)
Ha, not quite. I just saw that there would be a general increase.
However, I do think that with enough time, a small handful of teams might be able to crack that barrier. I think it's more likely that the top teams will be in the low/mid 4:00 range

Re: Duration

Posted: January 7th, 2012, 7:10 pm
by starfield
has anyone had success with the chinook design?

Re: Duration

Posted: February 7th, 2012, 1:58 pm
by jk2127
hey guys, i was wondering what kind of times people have been getting so far. thanks.