Fauvel flying wings

[Christian Husvik]

Hei,

it turns out Marske isn't the only one to try the stable profile flying
wing. Have a look at www.survol.cjb.net. Rather similar to the Pioneer,
isn't it?

Christian 8-)

[Birger.W...@dnv.com]

I flew the AV-36 in Vinon in 1967, remember it was rather touchy in
pitch control.

Birger

[Robert Ehrlich]

There is an explicit reference to Charles Fauvel by Jim Marske at
http://www.continuo.com/videowebpage/lloydupdate1/, where he says
that Fauvel's design triggered his interest in flying wings. The similarity
in their design is mainly due to the same basic choice, i.e. not
to get the stability by using a swept wing, which was the choice of Horten,
Northrop, the SB13 and numerous others, but to rely only on the reflex
airfoil for that purpose, which allows for normal or even slightly forward
swept wings with better efficiency.

[Marske Flying Wings]

Yes the Flying Wing has been around for quite some time. Another
influence was the planks of Al Backstrom. One of the reasons that the
Fauvel wing was not very successful was the lack of a good airfoil. Jim
developed far superior airfoils and refined basic layout.
-mat

Marske Flying Wings <mar...@continuo.com>

3007 Harding Highway East,
Marion OH 43302.
ph 740 223-3550

Marske Flying wings <http://www.continuo.com/marske>

[Albert Schmidt]

> Yes the Flying Wing has been around for quite some time. Another
> influence was the planks of Al Backstrom. One of the reasons that the
> Fauvel wing was not very successful was the lack of a good airfoil. Jim
> developed far superior airfoils and refined basic layout.

I don't agree. You can't say that the Fauvels were not very successful. More
than one hundred AV-36 or AV-361 have flown all over the world, it is
probably much more than all the Marske flying wings !!! The airfoil they
used was not that bad, considering that they didn't have computers at that
time ! Even if it wasn't the best airfoil for performance, it was safe, and
the thickness was seeked by Fauvel to make the wing lighter. Of course, it
is possible to have better airfoils in 2001 than in 1950... (especially
using X-foil or other software), and the latest Fauvel, the AV-451
incorporated a Wortmann airfoil.
Anyway, even with the Fauvel airfoil, stating that Fauvel wing was
unsuccessful is a bit unfair. The AV-36/361 is probably the most popular
flying wing sailplane ever produced, and it has never been designed to be a
high performance sailplane. Compared to the performance of other sailplanes
in the same category, at that time, it was not ridiculous.
As for the handling, I had the opportunity to fly an AV-36 in France a few
years ago, yes it is "different", but safe and pleasant, once you understand
the main differencies with a tailed glider, and provided that you have a
good CG location. Read the "in flight" section on www.survol.cjb.net, it is
very educational.

Albert

[Bill Daniels]

I had the opportunity to fly Jim Marske's first design, the XM-1 - a
constant chord "flying plank" that used a Fauvel airfoil.

The Fauvel airfoil was too thick and, more importantly, it had far too much
reflex. This resulted in an annoying "rocking horse" ride as the static
stability restoring forces greatly overcame the pitch damping. It had an
1-2 Hz resonance in pitch that was barely damped.

With unswept flying wings, there is a complex relationship involving the
degree of positive pitching moment (reflex), the distribution of mass about
the pitch axis (moment of inertia)and the wing chord. In the case of the
XM-1, these factors combined in an unhappy mix. In the case of the AV36, I
suspect that the wide chord provides enough damping.

Jim's next design was the Pioneer 1. As I recall, it used a slightly
modified NACA 23012 with far less reflex than the Fauvel section on the
XM-1. By reducing the pitch static stability to a level that the available
damping could cope with, the flight characteristics of the Pioneer 1 & 1A
became exemplary.

This experience led me to the counterintuitive belief that the mass
distribution about the pitch axis and the airfoil reflex should be at the
absolute minimum for best flight characteristics. This permits the wing
chord to be reduced for a higher aspect ratio.

Bill Daniels

"Albert Schmidt" <albsc...@yahoo.com> wrote in message
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