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Airplanes with flat plate wings

From bm459:

Exactly. The 'look' was what was driving the design from the outset. It went thru several iterations before arriving at the present configuration. Originally the plane was tailless, with extended 'tabs' on the rearmost ends of the elevons for increased pitch authority. The plane flew fine at high speed, but still lacked pitch authority at low speed. It also had adverse yaw at low speed. Finally i had to 'bite the bullet' and go to a conventional tail, ailerons and larger fin area, which cured the problems but with a 'looks' penalty.

Reply to
Bill Sheppard
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You and I must be like perverse spirits. I love homebrews. They often fly like crap in the first iteration. But start adjusting the various lifting surfaces for angle of incidence and ditto with the power plant and all of a sudden they can fly real sweet. I suspect your guy might have been ok with somewhat bigger tabs on the elevons and just a vertical stab on the tail. I have seen planes with only a vertical stab that flew with no real bad habits. I prefer a plane that keeps going where it is pointed regardless of reasonable throttle position and has no built in self correcting stuff anyhow. Makes them more aerobatic and as easy to fly inverted as right side up. You do have to fly them thou.

Reply to
bm459

From bm459:

Actually i kept increasing the size of those tabs till they bordered on rediculous. Even put a gyro (Ikarus microgyro) on the pitch axis but to no avail. The only cure was the longer tail moment with conventional stab/elevator. The inspiration for the plane was the X-Bow / Bird-of-Prey genre of foamies which fly tailless with no bad habits. I suspect my plane's AUW (15 oz) gives it a higher wing loading that accounted for its inability to fly tailless at low speed. Bill(oc)

Reply to
Bill Sheppard

I don't want to get caught up in the torrent of BABLE on this thread.

I would just like to say that I studied aerodynamics under Kermode a RAF Halton in 1944 and Kershaw at the Royal Air Force College in 1947.

These two masters of aerodynamic theory were often at odds regardin the best ways to calculate aerodynamic forces, but one thing they wer unanimous on was that the greatest part of lift on an airfoil i derived from the downward deflection of the airflow. ie:- F=MA

Cheers. Patrick. :cool: :) :

-- oldpilo

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Reply to
oldpilot

Thank goodness... no more "BABLE" (?).

Good flying, desmobob

Reply to
desmobob

Wasn't there a tower there at some point?

Or was it that fish from Hitchhikers Guide to the Galaxy?

Reply to
The OTHER Kevin in San Diego

Correct spelling: Babel. Root word of our English word Babble.

Dan

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Dan_Thomas_nospam

Reply to
The OTHER Kevin in San Diego

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