2.8 - 2.9 meter sailplane

[Charged]

Do you have any good model suggestions for this wingspan ?I want to build one .

[LVsoaring]

We need more information... are you looking for a simple 3 channel RES polyhedral ship, or a full-house model?

[Charged]

A yes, full house model with flaps and ailerons.

[aeajr]

That is a very narrow range. Why that range?

Wood? Foam? Fiberglass or other composite?

[Charged]

The category says 2.8-9 wingspan and full house .I just need a drawing .Whatever its built originally.I want to build it from balsa,glass and carbon.Like this ( http://www.rcgroups.com/forums/showthread.php?t=671727) but stronger and other structual improvements.

[Andy W]

You could always scale down a Supra, although it's for glass-over-foam construction.
http://www.charlesriverrc.org/articles/supra/supra.htm
..a

[aeajr]

The category says 2.8-9 wingspan and full house .I just need a drawing .Whatever its built originally.I want to build it from balsa,glass and carbon.Like this ( http://www.rcgroups.com/forums/showthread.php?t=671727) but stronger and other structual improvements.

Category? What category? You mean the title of this thread?

Are you trying to build something to fit a particular competition class? Sorry to keep asking but understanding your design goals helps us advise you.

You may wish to contact the AMA plans service if you just want plans.
http://www.modelaircraft.org/plans.aspx

FAQ
http://www.modelaircraft.org/plans/faq.aspx

[Charged]

F3J category is the competition class .Under 3 meter because its a bit easyer to build.

[aeajr]

Oh, F3J. So you need a strong wing/spar combo.

Do you plan to do a bagged wing or a bolded wing?

[rdwoebke]

That is an interesting setup, on that Tragi you linked too....

I'm not aware of many designs out there for fully sheeted wings that are built up.

You could just build a Bubble Dancer, if you like the "balsa/carbon/fiberglass" construction. It is a bit bigger than 2.9 meters but I don't think its extra .2 meters or so of wingspan will make it that much harder to build, and the wing is 3 piece so it won't be difficult to transport.

Ryan

[mhodgson]

If that Tragi you build flies well why not simply enlarge it?

[woro]

Because enlarging something 1.5 times is quite like designing it again. The scale will make problems. Scaling up is better than scaling down, but still quite dangerous or difficult-depends on how much will you design it like a new model more than something scaled up.

[Charged]

That 2 meter Tragis aspect ratio is not good when enlarged.I want a nice sleek sailplane.But ofcourse building this kind sheeted built up wing is much more complex than this 2 meter Tragi but i have thought about it and the technology is there .So i have to make carbon spars first because its not good to use filler on the spar and it wouldn't fit to the thikness of the skin .So i think it will be full carbon and a layer of glass to the length of 1.9 2 meters to save weight and loads will be smaller too after that length.And to make it simpler it will be covered with oralight because when i want to laminate it with glass i would have to bend it after curing what will cause unneccessary loads in the wing -it would be loose a bit.So now the skin will be like moulded after the profile and bonded directly to the ribs with the same resin what is in the carbon fabric and in balsa .Ailerons and flaps will be cut after both skins are on the carcase nad details like shoulder attachments in the ailerons and flaps and splines in the centerpiece will be figured out in the process like usually.The foam cores will be cut with CNC .These are the main things .Do you know if there is somebody who can cut me ribs from 1,5 mm balsa?
What means bolded wing ?

[woro]

He probably meant molded.