Elastic Launched Glider C

[science8]

I have a new question, will cambering the wings change the ballistic launch of the glider. At Northmont, I launched a flat wing in a "V" shape. It flies fairly decently but I recently have built a slightly cambered wing using the same techniques as my previous glider, and it just wants to nose dive. Any thoughts? Thanks

What place/time did you get at northmont?

I was forth place with flight times of about 10 seconds each. Wright State was similar, but I received 10th place as there were many more teams there.

Idea of the 1st place time?

At the awards ceremony for Conestoga, they said that the winning time was 36 point something seconds.

I believe it is with both flights together. So it was 2 18's i guess.

Well, if I heard the words correctly, he said "flight time", so in reality it could be either one. I'd need confirmation from somebody from Conestoga to know for sure.

And the 36 point something was 36.74.

Im just saying this because I asked some of the volunteers working at the event and they told me the best times were 18's.

[wlsguy]

Wright State had a top score of ~ 38 seconds (for 2 flights)

Good point Jeff. The ceiling was 24' unobstructed.

[jander14indoor]

Important factor with flight time responses, ceiling height at these invitationals?

I'd have checked for myself, but I was running Robot Arm all day.

Jeff Anderson
Livonia, MI

[2346273454]

At the awards ceremony for Conestoga, they said that the winning time was 36 point something seconds.

I believe it is with both flights together. So it was 2 18's i guess.

That is correct, the 36s was both flights together. When they said 36 it gave me quite a scare. I was thinking "Crap! That's nearly double my flight time!" and then got called for 1st place. It was a 19.4s flight and a 17.2s flight if I remember correctly.

Gym size was 35' by 120' by 120' if anyone was wondering, but only 30 feet unobstructed.

[2346273454]

Does anyone know if it is true that angle of incidence effects light planes more then heavy planes assuming that they are moving at the same speed?

[Orange714]

I was wondering how important does the straightness of your fuselage factor into your glider? I checked the fuselage of mine recently and they're not really straight as in one side is a warped up a little. I haven't been launching them really hard, but so far I haven't seen anything. I know it would affect your decalage and whatnot but how big of a effect does it really have....It's warped up maybe 3-4mm

Thanks in advance!

[2346273454]

I was wondering how important does the straightness of your fuselage factor into your glider? I checked the fuselage of mine recently and they're not really straight as in one side is a warped up a little. I haven't been launching them really hard, but so far I haven't seen anything. I know it would affect your decalage and whatnot but how big of a effect does it really have....It's warped up maybe 3-4mm

Thanks in advance!

The fuselage itself seems like it wouldn't be a huge deal. What would be a huge deal is if your wing was tilted/warped in a way you didn't want it to be because of that.
If your wing is tilted and warped, you might have to adjust the wing/tail a bit. This is something can be extremely hard to tell by just looking at it, so you just might have to test it carefully and see what happens, and then adjust it further based on that.

[gsjbjt]

To adjust roll, yaw, etc does the glider actually have physical flaps? On the generic designs I've seen on the AMA website at least, none of them have adjustable parts, really(but then I'm confused as to how you would trim/adjust these...?). We've been trying to cut small slits on the wings/tail to make the airelons, rudder, etc but after a lot of adjustments the slits typically get worn out and the flaps just fall off. I feel like we're somehow doing it wrong, any tips?
Also, where should the center of gravity typically be for the glider? Right now we have it at ~the center of the wing by adjusting the amount of clay weight on the nose, but apparently it's too much because it just nosedives..Then again if we remove most of the weight it flutters downward and inevitably breaks some part upon landing

[2346273454]

To adjust roll, yaw, etc does the glider actually have physical flaps? On the generic designs I've seen on the AMA website at least, none of them have adjustable parts, really(but then I'm confused as to how you would trim/adjust these...?). We've been trying to cut small slits on the wings/tail to make the airelons, rudder, etc but after a lot of adjustments the slits typically get worn out and the flaps just fall off. I feel like we're somehow doing it wrong, any tips?
Also, where should the center of gravity typically be for the glider? Right now we have it at ~the center of the wing by adjusting the amount of clay weight on the nose, but apparently it's too much because it just nosedives..Then again if we remove most of the weight it flutters downward and inevitably breaks some part upon landing

A glider does not need active adjusting mechanisms like flaps. What you can do is you can re-align the wing, move the wing forward and backward, change the incidence, change the wing tilt, add/remove yaw, and most importantly add/remove nose weight.

The key to trimming is to make small adjustments, glide test, make more adjustments until you are satisfied with the glide. Once it glides perfectly, figure out you can launch it and have it transition.

Small Adjustments

[gsjbjt]

I see....
So to clarify, it isn't actually the angle of the flaps relative to the part they're on (e.g. angle of the rudder relative to the vertical stab) but their angle relative to the entire plane?
What easily-adjustable and relatively easy-to-find glues are typically used? We've been using simple super glue just because it's easy to find, but it doesn't exactly make the parts easily removable; the top layers of the balsa typically peel off with it, or we get uneven grit-like glue still stuck to the surfaces.
Also- how is roll incorporated if the left and right airelons are meant to move up/down opposite to each other (can't really be imitated by adjusting the wing?).