Max after testpilots comments

I have been in touch with retired FAF testpilot ( who is also an aviation engineer by education ) mr. Jyrki Laukkanen ( like I mentioned earlier ). His expertise and my enthusiasm has been very fruitfull. He knows aeroplanes and their flying caracteristics possibly better than anyone in this country. Albeit his reluctance to see much positive aspects in a pusher in the first place I see his generous help to make this plane better has been obvious.

1. First he insisted to make the plane longer ( I added first 220 mm then 150 mm more ).

2. Yesterday he threw ( in e-mail ) me a minimum rudder area to be added to make this kite directionally stable ( it was so much rudder that I won't even show it to you ), but that made me think thoroughly the rudder aspect.

First the rudder ( directionally affecting stab area ) is now bigger than in Bede-5B ( fractionally ) and the rudder itself is fractionally bigger than in VmaxProbe.

To make the negative V effect smaller I drew the rudder less high than before, but added more depth and thickness to it to make it effective. I also increased the V-form and size of the elevator/vertical stabiliser considerably. I also made solid stabilizer since i figured the rudder was going to be too heavy ( and Jyrki Laukkanen saw no reason to have it ). All this has been adding the wetted area, but all this tuning has kept the total area very respectable in goal to achieve a flight with a 22 hp engine. I might also add that this AC:s aerodynamics will also be good with a 40-50 hp engine ( this will naturally inrease wingloading and speeds + fuel consumption = less flying time unless bigger fuel tanks ).

The enclosed comparison has some reference lines of the wing and rudder positions drawn above the profiles that you get a better idea how these planes are in relationship to each others. This doesn't make much sense because it is like comparing sweet potatoe, orange and carrot, but they all are high performance pushers ( axial thrust fans ).

Bede-5B wingarea is around 4.4 m2

VmaxProbe was 2.45 m2

Max III is 2.9 m2 ( fowler flaps extended 3.2 m2 )

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