Okay... this is also not a scale model... so a 6 foot ws is not absurd. Years ago I built a glider called the 'Pussycat" It was an RC glider launched as WP says with a 'hi-start' that is 60 feet of surgical tubing attached to about 300 feet of line. I bought that at a hobby shop (They are Out of Business now
) The model had a hook on the bottom, you hook on to the line and stretched out that tubing. This will launch the model and get it up in thermals (hopefully).
Anyway... suggestion for a 6 foot ws javelin...
Make the LE out of an "arrow shaft" use a hard wood dowel for the LE. then make a round notch in your ribs to match. If you have a dremel tool with a sander this should not be difficult. Make sure you put in Gussets at the break in the wing where the dihedral starts.
The model will be big enough for RC as was my 'Pussycat' had 2 channels for rudder and elevator, although I think the rubber motor will be in the way.
Good Luck, Mitch
PS I have hunted Pheasent and Grouse and Chuker... with a 12 gauge shotgun.