Hey. I am building a 120-inch twin over in the warbird section but can't get any answers there. This plane was a blown up plan that had a once piece wing. My questions:

The wing will be broken into three pieces right outside of the nacelles. The center section will be about 50 inches, with 35 inches of tip. I can get away with a 1.5 to 1 inch tube depending on where I put it through the ribs. Do I need a single tube or double tubes? This plane is going to be fast, so I don't want floppy wings.

How long should the tubes be? Rib spacing in the area is about 5 inches. Obviously I need at least two ribs to grab onto on each side.

Thanks for any advice/pictures that would help!

Does it have to be a tube?

Could be an "I" beam in a slot. Or two, one forward and one aft in the cord.

Certainly you'll need plywood ribs on both sides. I would think.

On my 2m span pattern planes the wing tube extends about 30cm into the wing panels.<div>The position is slightly aft of the main spar position, Thin Carbon fiber tube, about 2cm thickness.</div><div>BTW they are foam wings with no internal spars, only sheeted.</div><div></div><div>My 1/4 scale Byron Cessna 195 uses alloy plates built into the wing between the a double thickness top and bottom spar made of bass wood, then sandwiched between the spar webbing.</div><div>They only extend say 20cm into the wing. I'd say the main spar ones are 1&amp;1/4 x 1/8th inch in thickness. The rear 1/2 x 1/8th inch.</div><div></div><div>I wouldn't bother using anything other than carbon tubes. Super strong and weight absolutely nothing.</div><div>For your usage, 1inch at slightly forward of the main spar position and say 1/2inch slightly forward of the rear spar.</div><div>You'll need a light ply rib doubler at the critical points, make sure it extends under the spar.</div><div>It'll be the strongest part of the wing.</div><div></div><div>Troy Built Models stock tubes for the aerobatic scene.</div><div>Check them out and see what's available.</div>

hi
i am going to start a Citrabria Aerobatic Pro from balsa usa i been looking at it and it has some dieheil in the wing how would i do this ? ,should i put all the ribs together from each wing side and drill a hole at the angle for the wing tube i want the center section to stay on the plane and just the wings to pull off so it would fit in my small truck thanks rye

Rye,

Look into the use of wing struts. I believe you will find your answers there.

Let me know what you find? Be interesting to know what information is available about wing struts.