Don:
The wing will most likely have the leading edge slightly higher than the trailing edge, perhaps 5 or more mm, depending on where your CG is. You want to increase this incidence until it starts to stall on “letdown”, the later, slower portion of the flight (but before the rubber runs out completely). Then lower the leading edge until this stall just disappears. If you move the CG, do this trimming again.
The half piece of rubber at full tension will behave very differently from a full piece with partial winds! Are you backing off at all? Typically you will want to wind to max winds (find out where it breaks, and go a bit less than that), and then back off to your launch torque. Otherwise you will have way too much torque at launch, and the plane may spiral in. On half motors (0.75g), with a motor width of 0.0408g/in, we have been winding about 1300 winds, and un-winding 30-50 winds. Double both for a full motor. Your winds will depend on your rubber width. Do you use a torque meter? If not, you have to go by feel, you can really feel the rubber tighten up just before it breaks. But I would recommend a torque meter.
Chuck
From: Indoor_Construction_at_yahoogroups.com [mailto:Indoor_Construction_at_yahoogroups.com]
Sent: Sunday, January 22, 2017 10:00 PM
To: Indoor_Construction_at_yahoogroups.com
Subject: Re: [Indoor_Construction] Re: Any A6 tutorial?
Thanks for the info, Chuck!
My student did make a 1/4 length motor and weighted balsa piece 3/4 the length between the hooks. We adjusted the glide first, then tried flights with the short motor. Only one was made, because he over wound the motor on the second attempt, and it broke. He didn't have another short one. We did the rest of the test flights today with the full motor at reduced turns. Not great, but it did let us get the model trimmed reasonably. It's flying now in pretty consistent size left turns for the entire flight. The CG is as far back as we could make it and have it fly smoothly.
With the pylons vertical, the wing is tilted, not level. This can't be beneficial, but I wonder if leveling it could make much improvement. Any opinions?
We have one more chance to test fly it Super Bowl Sunday, before the local competition round. I think it may be adjusted about as well as it can, given it has a number of places the wing has slight waviness. It's pretty good, but it's not as true as a few indoor models I've seen pictures of.
Anyone interested can see a two minute half speed slow motion video on YouTube here:
https://youtu.be/ KdIb1aK5cwk <
https://youtu.be/KdIb1aK5cwk>
Don
Received on Sun Jan 22 2017 - 21:10:40 CET