Helicopters B

[Inergy9118]

I normally use a value of 100 turns per inch, but this batch of rubber is breaking at 94 TPI, so our team used 90.

That assumes a lubricated band that has been prestretched after tieing the knot.

Better times are achieved by having the chopper as close to the 3 g min as possible, having the blades absolutely symmetric, a proper pitch and having the right width and length of rubber for your chopper.

Are you using a kit??

Used a kit a first but it 's instructions were not good. Now using what was given at workshop with some modifications. Our copters are around 3.1. I read on this blog to use 2-4x motor stick legnth for the rubber, is that true? How do you do that with out the rubber hitting the Motor stick?

[jander14indoor]

Again, THERE IS NO RELATION BETWEEN RUBBER BAND LENGTH AND MOTOR STICK LENGTH. They don't have to match, they don't have to be specific ratios to each other. NO relation.

TYPICALLY, you want your motor stick to be only long enough to stabilize things, around 10 to 12 inches for this years rules. The rubber motor is then matched to the rotor to maximize time and is TYPICALLY longer than the stick.

It does not hit the stick because you space it away slightly AND because it shortens a LOT in the first turns where little energy is stored. By the time you get it fully wound you will have to stretch it to get it on the stick and the tension will hold it away from the stick.

Jeff Anderson
Livonia, MI

[Hosj]

Does the data you turn in have to come from one of the copters you run at the competition?

[Hosj]

Yet another question, sorry.

if I use the freedom flight model with 4 baldes on the upper rotor, shouldi have the bottom rotor be free or fixed to the motor stick? We got 55 seconds and 2nd at regionals with a 2 bladed fixed design, so maybe we could do better if it was free?

[jander14indoor]

Not official, opinion only, see soinc.org for official FAQs, etc, but...

Does the data you turn in have to come from one of the copters you run at the competition?

Nothing in the rules says it has to be from the copters you compete with, and I've never seen a log rejected for that reason. HOWEVER, that doesn't prevent some event supervisor I've never met (and there are a lot) from scoring that way.

Perhaps more importantly, WHY WOULD YOU WANT TO COMPETE WITH A HELICOPTER YOU HAVEN'T TEST FLOWN? That's just crazy. And if you test fly it, wouldn't you have data you could document in a log? And if so, why WOULDN'T you present that data?

There is NO risk providing MORE than the requested data, so why not? If an event supervisor rejects a log with 5 flights from copter one, 7 flights from copter two, 2 from copter three... and less than five flights from copter n-1 and less than five from copter n and you are competing with copter n-1 and n then you had no chance with that supervisor ANYWAY.

If you are worried about the event supervisor keeping your log (no reason to, but again, I'm one voice) just make a copy to present for the tournament.

Again, my opinion.

Jeff Anderson
Livonia, MI

[Hosj]

maybe I don't want to write down the number of winds, etc. i only have an hour to test it and states is saturday.

[jander14indoor]

Sorry, this is going to sound a little harsh, but if you aren't collecting data, you aren't testing, you are playing. Enjoyable in and of itself, but it won't help you win a tournament. You've missed the point of the event and why the whole rule about flight logs is there.

On I hope a more helpful note, have your data table set up ahead of time, you can record the data while the copter is flying. No lost time during the hour you have to fly.

Jeff Anderson
Livonia, MI

[Hosj]

sigh...

[silverheart7]

What is the best way to start preparing for this event now/over the summer?

[jander14indoor]

For events that aren't changing much, like helicopter, just use last years rules and work until you can match nationals level performance. While the rules change in detail, your ability to succeed at last years rules will directly transfer to success in next years rules. You'll need a short time to adapt to new details, but that's far better than starting from scratch. You'll know what is important and what is irrelevant. Allowing very focused work in the fall to bring modified designs up to nationals level again.

If you are starting this event new, read back through all the strings under this topic for this year, almost everything will be relevant to success next year.

Regards,

Jeff Anderson
Livonia, MI