Duration

[_HenryHscioly_]

i had another one, wihch i did practice in the gym,
but, just like, 2 flights or so, and then it got beaten up

i built another one; inside a classroom, 2 days b4 comp,
then,i wud let it go, it wud go up a bit, hit the ceiling and stay for a couple seconds, and come down,
it had almost like, 0 winds left, maybe 10-20?
so i cut up new motors at home and brought to comp.

[mrsteven]

What would have happened if it wasn't physically capable?

People wouldn't have made them.

well.. ya... I was expecting there to have been some sort of contingency plan... my b...

[wlsguy]

<SNIP description of impressive flight> .... ,

As per usual, not the place for clarifications, opinions only, etc.
If the fins were vertical, light a rocket, I don't see how physically they could provide lift, just doesn't work that way. If they were off vertical and moving sideways, its possible and is certainly at risk of violating the rules. I used to be an engineer working on air-to-air missiles in my youth (Sidwinder AIM-9M to be specific, scary how long ago that was, anway). Those missles flew mostly horizontal, and I can guarantee you the fins contributed significant lift at speed. It was a significant component of the flight model and range. Without seeing your design, hard to say.
....

I understand the fins would not provide lift IF the helicopter flies straight up.
Now, if the helicopter flies at an angle at any time, the fins will provide SOME lift.

Is this OK or would these be considered other surfaces to provide lift?

[Frogger4907]

I understand the fins would not provide lift IF the helicopter flies straight up.
Now, if the helicopter flies at an angle at any time, the fins will provide SOME lift.

Is this OK or would these be considered other surfaces to provide lift?

I think it would be okay and that there aren't many supervisors who are that picky about the rules, unless they are like big enough to be wings and your helicopter turns into a plane...

[jander14indoor]

...... Should we be scared? Remind me not to make you mad.... haha
Anyway, thats what I was thinking as well thats starting to hit the finer points of the rules where depending on how much the event supervisor knows about lift depends on it being tiered

You guys threw out the chinook without knowing? What would have happened if it wasn't physically capable?

Hmm, probably shouldn't mention the time I spent as a Nuclear Weapons Engineer... No the scary part was how much of an old fart I'm getting to be, I'm mostly a gentle soul... mostly...

If we'd known how to do it, wouldn't have been much of a challenge. And there was always the proven co-axial design to fall back on. We were expecting/hoping amongst thousands of teams under the pressure of competition, SOMEONE would figure it out. Looks like someone did.

<SNIP>I understand the fins would not provide lift IF the helicopter flies straight up.
Now, if the helicopter flies at an angle at any time, the fins will provide SOME lift.

Is this OK or would these be considered other surfaces to provide lift?

Again, opinion, and this shows why. I wasn't there, didn't see it. VERY hard to judge the specifics. As an event supervisor I would be more tempted to rule it illegal the more it deviated from horizontal, but would hate to give an arbitrary angle in advance. I watched some Wright Bat designs from back when this event started before folks figured out the coax design was way better. Some were clearly flying on the lift off that big stabilizing sheet, they flew almost horizontal. Others stayed close to vertical and got little if any lift from the sheet. But you had to see it to get a good feel.

Sorry to not be more definitive. But that's the best I can do from here. And that tournaments over at this point. Too late for any changes.

For those still to compete though, consider this advice I try to give often. If you aren't sure you are legal, is it worth the risk of second or third tiering over a slightly more conservative approach that places you high in the first tier? Not saying it never is, but it SHOULD be thought about. Of course you could minimize the risk with two copters. One radical, and one clearly legal. Get one good flight from each and cover your bets. There's so much more than pure science in SO, isn't there...

Jeff Anderson
Livonia, MI

[chia]

Wow, has this event gotten competitive. Went to regionals with a 3.51 g copter and a time of 1:50 or so on a 40 ft ceiling, and only ended up with 4th place.

[mrsteven]

Wow, has this event gotten competitive. Went to regionals with a 3.51 g copter and a time of 1:50 or so on a 40 ft ceiling, and only ended up with 4th place.

More competitive on helicopters than my regional- nothing broke 2 minutes

[chia]

Wow, has this event gotten competitive. Went to regionals with a 3.51 g copter and a time of 1:50 or so on a 40 ft ceiling, and only ended up with 4th place.

More competitive on helicopters than my regional- nothing broke 2 minutes

Seriously? At the supposedly most competitive regional? Hmm.

[mrsteven]

well, many builders who know theyre going to state like the powerhouse schools wont bring the good stuff so others don't copy/see the design so its likely this is true.

[sr243]

Can someone tell me how to get 2 minute+ flight times. I have tried different length rubber bands and such but I am stuck at 1:45. Using a 1.75g rubber band, I use about 800 winds and has about 150-200 winds left. It only get 1:40 on a 25 feet ceiling. Is it spinning too fast (avg 6.5 winds per second)? When I use a 1.65g rubber band, I get 650 winds and about 1:35 with <100 winds left. This has a slightly slower avg winds per second, but still seems high. Is there a way to slow down the winds at the beginning? It seems like the rubber band just doesn't last long enough to get past 2 minutes for me even though it has good lift.