wladkummer

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Since I live in Brazil and quality 2M kits are not available or very expensive today I´ve decided to design my own 2 meter plane. I´ll try to put my design and progress in this forum. Time is very scarce in my life, but I think I can have a couple of nightly hours daily. My first consideration was about the engine to use...I´d rather using a gasser because of the costs. Here we have the Kroma 30i (1.83cu.in.) which is rated at 3hp and said to turn a 18x10 at 7300rpm with a can type muffler (www.lem.com.br). The weight is about 1250g (about 44oz) with the ignition but without the muffler/pipe. Does this is enough to haul a 5kg airplane to perform the FAI sequence? Looking at the weight of the power package on the Bob Pastorello´s site, the OS160 he uses came out at about 1550g for the entire package. I think using the gasser I could come at about 1750-1850g.
So I have to built it light!
Here goes the basic outline of the airplane. The wing location may get foward of the presented depending on the weight of the engine package. The fuse will be built out of balsa and ply with slab sides and rounded tops and bottoms. The wing and stabilizer will be the built up type. I´ll be using a thinned down (11%) Eppler 168 airfoil at root and have not decided yet on the airfoil at the tip, maybe a 10% E168. The stabilizer airfoil is a EH 9% or will be a SD 8020.
Any suggestion are welcomed.
Does anybody has drawings of servos, receivers, hardware in DXF format?
So long....

flyintexan

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You may want to consider looking at the plans for the L'essence from RCM. It was a semi-successful gasser design and used some easy to find cores and parts to complete.

www.rcmmagazine.com


then click on rcm plans.

you can find it under the pattern category.

EL TEMUCANO

Wlad

Congratulations to take desicion to design your own plane.
I have designed several planes and i flown very much each ones.
Here goes two pictures. An Extra 300 with Quadra 35cc and my little pattern, thees little plane is very fast and its flight ir impressive, it can do kniffe loops, it´s my little plane.....

I think in our hobbie we have to design one plane to know thees feel.

Sergio

wladkummer

My Feedback: (7)

Very nice planes EL TEMUCANO.

My project is getting its form. Today I have mastered a little about Lofting in CAD programs and began drawing in 3d. It does helps a lot.
I am still desperatelly in need of drawings of a OS, Mintor, Webra engine in CAD as well as acessories such as servos, receivers, switches and like.

Bob Pastorello

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I'm glad you found the info on my website helpful, but I think you should recheck the math....adding up everything that has ANYTHING to do with the OS (except the prop and spinner, which you would likely use, surely???) I come up with 1335 and 1285, respectively with the Mac's pipe and the Aeroslave CF....what were you including that brought it to the 1500+ gram weight??? (I could have missed something you didn't)

I think the gasser is a great idea, and it should work very well....if you can keep the airframe light. And yes, moving the wing forward will be needed....I had a Hanson "Petrel" last summer, a one-of-a-kind that Dick Hanson designed at built, around the ZDZ 40 RE.....good design, great flyer, but I couldn't manage the throttle....and it was loud.

Keep us posted on your design!!

wladkummer

My Feedback: (7)

Almost finished lofting the fuse by now...kinda I just got a hand on this...

Hi Bob,

Glad to hear from you. In my math I´ve included the prop and spinner. Just to give me a final figure of how much a complete powerplant would weight. I have to come with a airframe weighing a max of 2200 in order to come below 5kg. Since I´m planning building out of balsa, white glue, minimal epoxi, dope and litespan I think a 2600g finished airframe (with l/g and wheels) figure is more realistic.
Anyway by that time I hope FAI set the max weight to 12lbs (5.5kg)....