ave aaircraft F- Yellow 16 DF (green fiberglass) version that i want to convert to JJ1200 or JJ1400 power - any idea what needs to be done ? Shaun from YA told my friend we would need to glass the wings to the fuse, but the plane is already built and painted - is it mandatory then ?Has anyone tried this combo or a similar combo ?

Thanks.

If you fly the airplane at ducted fan speeds, there is no need to do any modification (presumably the airplane would have held up on DF powerplant.

If you decide to go all out on turbine power and find it important to turn and come back, you may want to make a very very big circle

Use your head bud, what makes the most sense, putting a 2000 engine in a 500 dollar airplane and running a risk? or breaking it down, building it right, and enjoying it for years?

there is the speed component, but the weight combined with that is where the issues arise with any df conversion. if it is not a difficult paint scheme to repair sand away and run some glass along the wings to beef them up. the planes were designed to fly at 10-12 lbs and when you get to the 15 to 17 area you are stressing the airframe.

A likely sanerio: As seanreit posted else where: http://youtube.com/watch?v=DWHCzoaDz_U

You can glass the wing/fuse fairing all you want, but the problem really lies in the wing spar, which is part of the fwd and aft former.

This is what I would do and take it for what its worth. Cut the wings clean at the wing/fuse joint. Buy a set of wing mounting kits from Yellow (as used on the Epoxy version) and mount them to the bulkheads, then use the carbon rods to atach the wing to the fuse.

You will need to cut through the wing to add hardwood blocks where the carbon rods are glued in.

This is not really difficult and any damage done to the wing during the removal process can be fixed by adding balsa blocks and reshaping to match the airfoil.

There's many advatages to doing this such as:

-removable wings
-your current model has a rigid wing spar, you won't notice how bad or weak it is until it breaks.
-the carbon rods are actually flexible, so they help alleviate stress during not so great landings

You could also cut the rework time by 1/2 if you just buy a new set of wings from Yellow.

Best luck,

David

[&o]

Hi,

All is not lost. Like previously stated, doing the reinforcement isn't the end of the world. You could, if careful, leave the airplane with very little appearance deficit after the mod. Sanding off the paint and primer; then doing the glassing; then smoothing it out; then repainting it white sounds a lot worse then it will probably look when you're finished.

The spars alone are not enough, in my opinion, to hang the safety of the plane on with the increased weight and speed. The spars are an integral part of the wing structure, but they're not the whole picture. Another very important part of the structure is the wing-to-body joint. If the joint were to be comprimised, the spars may not hold the wing on (by themselves) for very long. Since you're talking about a plane that's obviously at least 7 years old--then so is the glue joint. With the glass in place (and I'm talking about a 4" wide, chord-length strip of 6-oz cloth), you'd be in a much better situation flying it on the power you talk about.

Whatever you decide to do, just make the decision to do it and dive into it. That'll get you halfway there. Think about it--you could have been done with the mod if you'd started the day before yesterday! Either way, feel free to call. I'll help you do it.