non-sheeted airfoil question / design advice

[chlee]

Hi everybody,

Need to ask some design advice of you folks: I'm thinking of building an all-wood 116" span RES ship. The challenge is to build an economical design with reasonable performance, using just spare radio equipment and wood that I have lying around. The glider will need to withstand modest, pulsed winch launches, but no zoom requirement. Target weight is < 45 oz. I know many excellent designs with these specifications already exist (Majestic, BoT, Paragon, etc.), but this is just for the fun of "rolling my own."

I'm inspired by Blaine Rawdon's Mirage with its non-sheeted wing and 1/8" stick turbulator spars, which gives it very low yaw inertia and a transparent, free-flight look.
So, the question is: what airfoils do you recommend for a non-sheeted wing? E-387 seems to do very well with turbulators (according to the UIUC/Garton website), but it has 'undercamber,' which is annoying to build.

The other option would be to go with the AG 34-36 series, although these likely require D-tube sheeting to do them justice. They're also a bit thin for an all-wood wing.

What do you all think? Comments, suggestions, and advice would be appreciated.

-Chung

[markdrela]

The Mirage is a lot of bang for the buck. I have full-size plans for it which you can borrow. I suggest building the same or similar wing, with a wood-pod/CF-boom fuse. The thick Mirage airfoil is well suited to its non-sheeted construction. Forget the E387 -- it's too slow, no better than a flat-bottom section.

The 4-layer BD boom trimmed to perhaps 33" will work well with BD-size tails. The tails can be made lighter for a histart glider.

Yes, you have to buy the $20 boom, but this will save significant amounts of fuselage wood and some building effort. And of course it's much lighter and tougher than an all-balsa fuse.

[Aio_1]

On the same topic but different aircraft: -

Anyone got airfoil suggestions for an open structure 1m aileron equipped pod and boom HLG? (not sure if it's getting a rudder yet)
Intended for non-competitive HLG and playing around on small slopes in light wind.
Area around 14 sqdm (217 sqin)
AUW about 160g (5.5 oz)
I'd appreciate any input.

Chung - I hope you don't mind me adding this to your thread, but I thought as your title covers this too.....

[chlee]

Professor Drela, thanks for the reply. A Mirage wing on a pod-and-boom fuselage sounds very interesting... May I actually take you up on your offer about the plans? (I'll send you an email.)

By the way, I'm the student that you helped with the Chrysalis HLG at the athletic field a few months ago.

Aio, no problem; I'd like to know myself.

- Chung