Vale Gliders
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Span : 60"
Wing section : MH64 thinned to 7%
Root : 11"
Tip : 6.5"
Weight : 42ozs
Wing loading : 11.6ozs sq ft
Length : 30"
Ballast : 3 slugs, 12ozs each (36ozs total)
I've been fascinated with flying wings for a while, and after building and flying a delta wing combat model decided that i needed a composite plank. Watching a zipper flying in the lift ticket video probably didn't help either, and gave me the idea that it would make a good DS learner plane, plus relatively easy to replicate after crashing. A blue foam plug was shaped and then covered with epoxy and 6oz cloth, sanded and filled until smooth, then a mold was made. I had no understanding of wet seam lay-ups, incidence pins or that polyester molds warp if you leave them in the sun, just had to make a mold. Well it worked fairly well, and with tinted yellow epoxy and a 2oz veil, 2 layers of 6oz cloth and 6oz carbon from nose to start of fin has proved to be very tough. The wing is blue foam cut out with a hot wire bow, 2oz veil and 6oz fabric layed up on one side using a mityvac hand vacuum pump. Then cut out a couple of channels and made up carbon tow spars with end grain balsa webs, then vac-bagged the top skin on. Hinges where initially kevlar, but where ripped off in a severe landing and have been replaced with silicone.
The white bits on the molds are chips that i have filled with car body filler, all part of the learning process, like furniture wax is not mold release wax, and pva wood glue is not the same stuff as pva mold release. I cant help it, just have to try the cheap alternatives to see what happens.
Flying
Now the best bit, first test flights with a wing can be exiting, getting the c of g and elevon deflection right is a challenge, but once sorted I started to really enjoy this plane. The c of g has been gradually moved back and elevator throw decreased, I've also learnt that planks like negative differential, and once i had more down aileron than up the rolls became nice and flat. I have also started using exponential on the elevator which helps me move the c of g back even more, it just gets better and better, its a very manoverable, fast, fun plane to fly and has fulfilled all my expectations. Installing a ballast tube was the next logical step, might have overdone it a little as I can fit three lead slugs, each weighing 12ozs. With 1 slug its just so much better, and as long as you keep it moving around the sky doesn't really seem to need any more lift. 2 slugs makes it a stronger wind ripper, it really goes and the rolls are blink of an eye fast. 3 slugs is outrageous fun and have flown it at this weight in under 20mph winds on pretty average slopes, though it really gets a move on when the wind is up over 30mph. Using 3 slugs has made for some interesting landings, too much weight for its structural integrity.....I've broke it a few times and had to really improve my landing skills, which is a good thing. Having gone through a couple of fuselages, I have now worked out where to make improvements and am currently working on a new plug. Access inside the fuselage is challenging, especially the fin area, which makes wet seam lay-up very difficult. The first 2 were taped seams, but after a heavy landing with ballast on board the back end tends to split open along the seam, so I really need to master wet seam lay-up and build my molds with this type of construction in mind.
Backdraft with 24ozs ballast 12.1mb. First successful headcam flight, plane does go out of shot a few times, but overall came out quite well.
This site was last updated 01/16/07