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I’ve been working on the wing arrangement for the reverse pou.  Mmmm  that’s not a good name.  What about Duck pou?  Sounds too much like Duck poo.  Pou Canard?  Clumsy. Axel Pou – after the aerodynamist Axel Darling, who worked out the aerodynamics of this configuration, and showed it to be significantly superior to the Mignet (et al) designs.

Quite apart from it’s rather racy lines, this configuration (in Axel’s words) IS VERY INTERESTING:
Consider the stability of such a planform… the N.P. is going to be much further back than in a standard Pou planform, even equal span, equal chord.

For instance, with 4.4M forespan and 5.8M aft the N.P. is
~1.3M as apposed to .997M for your planform. That’s
41.3% as opposed to 31.65% of total chord – all else in
form, fit and function as a real Pou, not a tandem.

In a complete analysis several things crop up but the most
obvious are foreplane loading is greater, say about 1 lb. /
sq. ft., (Better) but is still mushes at only about 44 km/h
(+20 degrees incidence.) AND it always remains in laminar flow with proper entreplans [ed: interplans = wing gaps vertical/horisontal]. In this case, the foreplane is lifting at about CL=5 in the center and like most other laminar scenarios in the Mignet/d’Escatha formulas, the total lift coefficient for the wing system exceeds CL=2, which is over twice that of a conventional Mignet planform.

An interesting aside is that as lift distribution across the spans is different because in the larger foreplane planform the aftplane is severely and almost equally suppressed from tip to tip, the smaller foreplane leaves lift bumps at about the vortex locations [Ed: at 89% wing span], which when the aeroplane yaws, allows a much greater yaw/roll force and much stronger dynamic lateral stability and much better and immediate pilotage in turns. This undoubtedly is the reason why the mad professor exclaimed that his backward Pou flew so much better than the reverse.

So, the first 25% scale model I’ll build and test will be the “Axel Flea”.

The plan is to cut a fuselage out of 30mm blue foam (of which I have a number of sheets already, and to then 3D print the two front wing supports. (just because I need an excuse to use my 3D printer for something useful).  Standard RC servos, and control linkages to mimic full-sized Fleas will be used.

I’ll CNC carve the wings (NACA 23112 airfoil), and slide in a CF rod for stiffness.

I actually can’t fly RC planes, so I’m going to try to tether the plane to a stake and fly it (with my RC controller) in circleslike the Control Line guys do.  The aim of the exercise will be to observe:
(1) the slow flight characteristics (how does it stall, and what about parachutal descent?)
(2) What effect will fast flight have on aircraft controls?
(3) Using very small capacity batteries, how long will straight and level flight last (i.e. a crude way to measure aerodynamic “clean-ness”).  Axel Darling claims laminar flow of both wings.  This should be interesting to observe with wool tufts to verify on the video camera.

And there you have it.  Let me know what you think.