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BAD SPAD (35.5cc home built S.P.A.D.) specs/info/plans.

I have recently built a giant S.P.A.D. gasser (I call it BAD SPAD). And have completed a short maiden flight with an engine out and found the following: it fly’s slow, stable, climbs well, seems to stall gently by mushing out, glides very well, is forgiving, and very cheap to build. I’m thinking of putting plans/instruction to build it here on the forum. I am asking all those reading this to please tell me if they would like to build this plane. This is still a prototype but looks promising. I will update the performance info after I fly it more. Any questions, please ask. I would be flattered if anyone would have interest in building this plane. The plans would not be blueprints, but I know that when I was designing this beast I would have loved some guidelines. So, guidelines are what I’m here to give others looking to get into giant models. If you have interest in further information about this plane or would like to get instructions to build it, please let me know and I will do my best to fulfill your wishes. Contact me through the forum; I will have it set to email me,
Here are the specs:
> 8 foot wingspan (truly 97” due to coroplast sheeting size).
> 72” inch gutter pipe fuselage.
> 35.5cc converted chainsaw engine (could probably take up to 50+).
> 8 standard servos.
> 20 pounds flying weight.
> super light wing and cube loading (23ounce per sq. ft.).
> Overall length about 80”.
> Flaperons or flaps.
> Super easy to build with normal tools.
> And anything I’m forgetting (please ask!).
>2 4’X8’ sheets coroplast for wing and tail.
> One board for milling the wing spar, or something from coro or gutter pipe could be made to work.
>One piece of gutter pipe at least 72 inches long (sold in 10 foot lengths).
> 18” gutter pipe for control horns and wing attachments + some for tail (should be leftover from fuse).
>converted chainsaw engine (or use one designed for flight) 30-50cc maybe more.
> Aluminum flat for landing gear.
>misc. music wire, bolts, rivets, wire, RX, prop, engine mount, and anything I’m forgetting.

There is one con I have noticed: the tail flexes a fair amount, but could be stiffened.

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Build another!
Wow. Not what we usually see around here. Good thing I've moved into a condo. If I had an old lawn mower or some extra weed whackers lying about it could have gotten expensive! :D

Just in case I move again, define 'standard servos' please...

standard size, usually about 50 inch ounce of torque. they are basically the run-of-the-mill servo, i can recommend the hitec hs-311's for someone on a budget.

EDIT, DO NOT use standard servos (see plans)
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That's a sweet SPAD! Even in the lower 48, coro is running around $20/sheet, so $25 isn't too bad. From a strength to weight ratio perspective, the coro really starts to make sense in large planes. Yours looks like a good one. There are some plans out there for a similar plane with an extruded aluminum fuselage, but the gutter pipe seems to be a bit more economical. I wouldn't mind a set of plans.
alright, I'll get to work on some instructions/plans. it will take a while to get them all put together. i would like to try 2mm on the top of the wing but 4 does work. any incite on this? does anybody here know what a RNAF wing is?
You mean a Red Neck Air Force wing? I forget which plane they designed it for right now, late night up early and all but the SPAD USS uses one and is a good candidate for a 30-50 or more CC engines.

For the large plane using aluminum you're talking a SPAD BuHor (Big Ugly Hell on Rails) and while that's designed around a 46, a little math will let you expand that style of fuselage.

There's a good number of SPAD designs over on the spadtothebone.org site, it's a redesigned directory from the SPAD site I set up so many years ago and was done by Frosty.

http://spadtothebone.org/plans.html will get you to the plans page, shoot my plane The Flipper is even on there.

And links to tips n such. Over on Spadworld.net there is a video link forum to planes built by Draftman Which shows basic techniques of how to build and work with the coroplast material. In the building of a SPADstick in his video he shows the construction of a RNAF wing on video 4. These are linked to youtube from the spad site but however you get there it will show you how to do it.
We didn't have the production capabilities that Chad gave Flitetest, man I wish we had, but if there ever is a question about SPADs, give me a holler.

One thing though, also look at the thread over on RCGroups called Beyond Gutterpipes ... I build, fly and crash model airplanes but the thread originator there makes masterpieces. Scale planes from coroplast that are SCALE. You know the feeling. You think you've got the whole thing figured out and someone comes around that blows your doors off. I keep thinking Saliaria and Mozart here. Extreme Sports is G O O D. and the RCGroups forum is about the only active SPAD forum I know of anymore. With bind and fly planes so cheap and good folks don't really want cheap, bounce-able airplanes that you have to put together.

Tough? The airplane in my Avatar is my SPAD USS. The photo taken after I landed it into the back of a semi trailer. Somebody was a little farther away then he though when he was flying inverted and ran out of gas. Oh, I had to replace the prop and bend the gear back to usable and there are some crinkles in the coro fuse but they just match the wing which has been on three fuses now. Getting a little long in the tooth come to think of it. That semi accident was two summers ago.

There is a way to make articles on this site and you can link your article to this thread OR start a new thread when you get it done OR just add the info here I would think. If you have any problems creating the article give the flyingmonkey a pm and I'm sure he'll show you how to do it.
Like your ski's by the way. Those might be worth an article on their own.
I would definitely build it, but first I need to figure out where to put it :)

I was going to mention sign shops throw out a lot of coro in all sizes..no full sheets of course but usually big enough to use. Smaller pieces can be put together to make wings etc., a layer of duct tape top and bottom on the seam works good. Just stop and ask and usually you can get some free, also a good source for adhesive colored vinyl.

Any chance of a video? I bet that is fun to watch fly!

thanks for the info Mrclean! i have looked at spad to the bone, but have not found a way to post on the site.
StuartPB, i am working on the instructions, and will pre-release the material list soon.
Bobk, thanks for the interest. the wings come off with three bolts making storage a lot easier.i am liking the idea of the vinyl, could it be used in structural applications instead of packing tape? i like the clear instead of duct, but adding flair with vinyl sounds great! as for a flight video, i have only made one flight with it so far which ended in a dead stick landing. however i do have a flight video which i might try to put up.
Ok folk, a quick update. the plans are slowly coming along. i figured out what my engine problems where, so a second flight will soon follow. hopefully then i can give a more detailed flight performance report.