Thread: Build Log E-Scorpion
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Old Jan 27, 2013, 07:40 PM
CoolerByTheLake is offline
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United States, MN, Hermantown
Joined Dec 2008
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Build Log
E-Scorpion

Thought I would try my hand a building a foamy, need a project to do while I rehab. The pic below gives you an idea of shape. Some preliminary numbers.
WS=52", L=61.5" Power=JF90/Het 700-68-1200Kv on 12S. Wing area =715sq.in. Retracts, with ailerons, flaps,split elevators, rudders. Component weights come to approx 6.5lb. I asked J Morgan to guesstimate a weight for a fuse, his guess, approx 4.5lb. Also, there should be some additional lift due to the large bottom area. I should see around 11.5lb thrust/and approx 4.4-4.5Kw.

So I am looking at around 11lb, will try to lighten it some! Better than a 1:1 thrust ratio, and approx 400+W/LB. Wing loading is a little higher than I would like, but I think back about C/N's JHH-F-86, I think it was 13lb at 3500W. C/N, correct me if I am wrong!
Plans are drawn, templates cut for wing, stab and tail cores.

Just thought I would run this by you guys before I start any building. I know this is just asking for it, but any thoughts or opinions.

Addendum: In talking with some other members of RCG, they wondered about my numbers. Just for comparison, lets use the Y/A Starfire, specs are close.
Specs:
Length:......................62 1/4"
Wing Span:................50 1/4"
Wing Area:................620 sq."
Weight:.....................10-11 lbs
I seriously doubt that any actually came in at that weight all dressed out. And yet they flew very well on the OS91/Dynamax system, with possibly less thrust than my proposed EDF set-up. All things considered, I think I'm in the ballpark.
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Last edited by CoolerByTheLake; Mar 11, 2013 at 11:56 PM.
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