MotoBird - 2 seat aircraft with Rotax 503

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4-e-v-e-r

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Feb 23, 2020
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Looks really good especially if you get the same results with both meshes. Thanks again. Doug
The results were practically the same, but anyway I'm looking forward for a fly test. It's not easy to calculate drag of such type of an aircraft, I'm using statistical data. And also the wing should not produce so much lift (comparing with calculations) cause I use fabric covering.
 

4-e-v-e-r

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Feb 23, 2020
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I think a version of this design set up for heavier pilot weight, no passenger, and a current-production engine like a Polini Thor 250 could interest amateur builders in the LSA and microlight categories.
Very interesting comment, thank you! I planned to use a current-production engine in future, plus you can't use a passenger option for a part 103 aircraft. Using this design for a heavier pilots is a good idea.
Polini Thor is not powerful enough for such type of an aircraft because of high drag.. But it is a very interesting engine to use)
 

4-e-v-e-r

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Feb 23, 2020
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Sorry, you lost me there. A 40 hp Rotax 447 works for two people but a 36 hp Thor 250 isn't enough for one person...?
For me 40 HP is not enough for two people, its a compromise..
The main problem for me now is balance between weight and safety, I gonna finish the prototype and then make a deep analysis. What kind of aircraft I can design in this class. Two seat with 36-40 HP is the only way I see now, but.. time will show
 

4-e-v-e-r

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Feb 23, 2020
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The first cockpit design was based on statistics and CAD analysis, but I'm sure it is necessary to check it with real pilots, that what I did and that found the most suitable seat shape. Anyway it was then modified.
 

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4-e-v-e-r

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Feb 23, 2020
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I redesigned the FWF part, actually.. I made f firewall Around the engine, I don't want pilots legs and arms to be damaged in a case of fire. I gonna use 0.02 aluminum + Zircoflex flexible ceramic heatshield. It will be lighter then using a 0.02 steel firewall.
 

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dino

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Why use a laminar flow airfoil on a fabric covered wing?
 
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4-e-v-e-r

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Feb 23, 2020
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Why use a laminar flow airfoil on a fabric covered wing?
I use it because it's a high-lift airfoil for a low Reynolds numbers. It's the way I could you a smaller wing.
This airfoil is also used on a fabric covered wings.
 

Martin R.

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Mar 21, 2019
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24
Very interesting project. And a perfect way of proceeding.
Congratulation :)

When I study your table in posting #2 I have some questions:

- What will be the span and surface of the tail section and where will be his position in the part "prototype"? And

- which values do you plan to use for the wing area, the span, the lenght and height in the part "115 kg"?

As you are "working" with an empty weight of 254 lbs in the "115kg" column, I guess that you are thinking of the US part 103 restrictions.

If that's the case, what are your "ideas" to realise a stall speed of 24 knots?
 
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