Today we reveal the secrets of how to make simple gliders soar. It may look like voodoo, but you can do it too! Aleda catapult/chuck glider for beginners: jhaerospace.com/product/aleda-...
Thank you for this. You have packed an enormous amount of useful info in a video without a second of irrelevent blather. I encourage you to hook up with a pro with a good camera. Your presentation deserves it. Thanks again
Matthew Taudevin, I learned that about 8 years ago and have been doing it ever since. Makes a huge difference. The planes will literally hold trim for years if stored correctly.
Good Stuff Joshua! One suggestion: Have the “camera” person stand behind you as the plane is launched, with the “camera” pointed along the expected flight path so that the full transition is visible in the video. This way the plane won’t disappear from the “frame” and then reappear again at altitude, leaving us to only imagine how it got there. Thanks for your efforts!
Great stuff and thanks for sharing. The “thud” at the end was funny! 😀 To get our catapult gliders to turn, we use tail tilt and it works well for us. We have not used trim tabs. I’m curious about your thoughts on that?
You need a little of both. Using rudder as part of it forces the model to bank out of a stall recovery instead of pitching back up. You can then fine tune the glide circle using stab tilt and in some cases wingtip weights.
I also use a screening tool to create a slight bend by making 3 lines parallel to the leading edge of a foam wing to create a slight arc for a slight airfoil
I have done a lot of those foam Chuck gliders I have done large Chuck gliders from balsa and foam board , Manila folder , paper I'm really good at that
good video, thanks. My wife came up with a great idea I have used on foam wings and stabilizers. A cookie dough roller used on those surfaces with the center top as a base allows trailing edges to be squished thin and leading edges to be rolled. Experiment
almost a year later.... don't give up on the foam board quite so easily. at a hard table edge you can roll the leading and trailing edges down really thin with a chunk of 1" steel pipe (top side), then wrap tape half top half bottom (stays flat) develops a bit of air foil and reduces frontal surface area drag a bunch. do it aiming for mid point on the elevator, on the rudder do flat for the left side (sideways air foil to the right side will pull to steer left). for gliders a little larger, you might even approach balsa flight times.
model nutty yeah but the point was to keep it simple and within reason, so I didn't want to do on foamboard something that would be significantly easier on balsa (leading edge shaping) just like I wouldn't do on balsa something that's easier with foamboard (KM airfoils, for example). We kept the models small to stay within the bounds of an AMA catapult because of safety concerns. If you watch my "big catapult glider" video, you'll see that larger models of this type really are quite dangerous, and we're still trying to find a good way to mitigate the extreme risks involved.
All of the AMA rules are hosted on the AMA website and updated regularly. Here are the ones for outdoor free flight: www.modelaircraft.org/sites/default/files/files/OutoorFreeFlight2017-2018.pdf
Josh I built a carbonette 8 and it flys well, my problem is it tends to dive for a short distance after transition then goes into a nice glide, it loses a bunch of altitude My best so far is 45 seconds Any help would be appreciated Thanks
Shoot me a direct email at joshuawfinn@gmail.com for more specifics, but in the meantime, I need to know if it's stalling into the glide or rolling into a dive at the top. The former is generally not enough left rudder, whereas the latter is usually from either too much, or not enough washin on the left wing.
I'm glad that someone agrees with me that foam board is much much too heavy for gliders, and makes terribly inefficient airfoils. But, I'm wondering, what is that glider that has the two-tone wings, which is to the right at the end of the video. Do you ever fly it in the video? It looks neat. I'd like to see it fly. Also, you are releasing kits for the balsa glider, but will you be releasing plans?
The two tone is a Carbonette 8 that I built a couple years ago. Unfortunately I lost it a couple weeks ago demoing it for some DLG guys. Plans will be available soon though. The balsa model I trimmed in this video, now named Aleda by my bride, will only available in kit form. However, plans for the foamboard model are already online here: forum.flitetest.com/showthread.php?37668-Let-s-talk-about-chuck-glidersYou could easily make those wings from 1/8" balsa and the tails from 1/16" and have a very nice flying airplane. The weight of the foam really isn't bad, it's mainly just a function of drag. If Flite Test would release their thin foamboard, we'd be having a much different discussion.
I might look into building those plans. As for the weight if foam board, I suppose I agree with you that the actual material is not too terribly heavy, but try to make any sort of airfoil with it and you can easily have a 1 meter wing weighing upwards of 120 grams, which I guess is fine for powerful RC models that fly fast, but for models like gliders which need to be efficient in the amount of thrust they deprive from falling(cause that's essentially what they're doing) foam board, as you said, is rather problematic, in both its weight and its lift to drag. On the subject of thinner foam board, Flire test recently released a vlog which focused on the fact that a member of their staff had succeeded in convincing Adams Foamboard(the company they buy from) to produce thinner Foamboard to facilitate their making scaled down versions of popular Flire test models. If they could make thinner Foamboard for the flite test guys, that shows that they clearly have the facility to do so to a greater multitude of products. So, who knows, maybe thinner Foamboard is something to come! Anyway, I was also wondering about how much weight the slivers of wood add to gliders. I would figure that it's gotta be a pretty significant figure... Also, I usually bend surfaces for trimming and have found that surfaces which are bent can hold trim for months without deviating in the slightest. Do you think that the weight saved from not adding wood is worth having to adjust the model every few months?
Copterdude, the tabs only add maybe 50 mg each if you're really heavy handed with glue. insignificant in the grand scheme of things, and the tabs here were exceptionally large. Buddenbohm fuselages have screw adjusted fuselages... as for DTFB wings, check out my Spinster DLG...comes out to a competitive weight. I heard that FT cancelled the thin foam. please please contact them and express your desire for it. I really want the stuff and don't care that it's not much lighter. we need thin!
As for the tabs, well, I'll give em a go! Can't hurt to try! And as for the spinster, I've actually been meaning to sit down and build one for a while now, but you know how life is...well, I'll build one soon enough. The flying season is coming to a close though here in New York so I may wait till next spring. I'll just see what happens.
If you join National Free Flight Society, they have a huge archive of the annual symposia which includes many articles showing stability analysis of gliders.
It's just not practical to go in a straight line. These planes cover enormous distances. A typical catapult glider covers easily 1/2 mile on a decent flight. The other benefit of circling is that you can get the plane to center up on rising air currents called thermals, which greatly extend the flight time (and the fun).
There are a full line of such kits here, based on the work we did in the above video: jhaerospace.com/product-category/free-flight-kits/outdoor-gliders/
