Yes Graham thats all very good but we're talking about an aircraft that can
fly point to point=2C airport to airport at 112 mph cruise=2C
1.2 gph yielding 93 miles/gal with no ground crew or tow plane. This was w
ith a 24 hp Koenig two stroke. A four stroke would break 100 mpg. Also=2C
19/1 L/D is phenomenal for any type of powered a/c. Even the Europa barel
y breaks 10/1 L/D.
Also=2C after flying hang gliders sucessfully for 27 yrs (except for knocki
ng out two front teeth - damn that hurt!) I can attest that it is very eas
y to break a deep stall in a very lightweight aircraft by simply moving the
pilot's upper body weight forward!
@Peter=2C I remember now changing the airfoils from a Wortmann FX series to
a NACA 23012. This was to reduce what I thought was
excessive negative pitching moment in the a/c at higher speeds. With the 2
3012 there is almost no -Cmo requiring just conventional
retrimming for higher speeds. Here is a page showing technical specs and d
imensions for the Stratos:
Specs: http://users.mo-net.com/shirl/LigetiStory.htm
3 view with dimensions: http://users.mo-net.com/shirl/Stratos3ViewWeb.jpg
Glenn
internet.com>> > Glenn> 19 to 1 is not a very good L/D=2C the best gliders
are up to 60 : 1 now. > The glider boys have a mantra " TINSFOS!" there's n
o substitute for > span=2C and a 60/1 glider has a span of around 30 metres
.> Induced drag is a function of the downwash angle=2C and lift is a functi
on > of downward momentum change. Lift equals mass of air deflected (by the
> wing) X velocity downwards squared. Not quite as simple as that but I >
hope that illustrates the point? The wing deflects a cylinder > (elliptical
section) of air and the bigger the cylinder the less the > angle you need
to deflect it. Trouble with tandem wings is that the > following wing has t
o use air already deflected by the leading wing so > it doubles the deflect
ion and therefore doubles the induced drag.> Now=2C canards are not unstall
able. Very stall resistant but if you do > have a stall it will be very res
istant to unstalling. Known as a deep > stall=2C not enough pitch authority
to unstall the wing. Burt's microlite > canard was very nice to fly but it
was possible for a gust to stall both > wings and nearly impossible to rec
over. Mike Melville did recover (from > a spin) but lost around 7000 feet d
oing it. This is why our leader Burt > gave up on canards.> Graham> glenn c
rowder wrote:> > This is an incredible concept that has not been utilized I
MO. The > > joined wing concept is the most efficient per NASA studies> > h
ttp://www.aoe.vt.edu/design/ikelos/ as it eliminates the draggy tip > > vor
tices that plague all other designs. The Stratos has> > an L/D of 19/1 and
the original needed flaps to degrade the glide > > enough to allow a steepe
r landing approach. You have> > effective sailplane efficiency in a very co
mpact planform. In > > addition the wings can be made much lighter as the j
oined wing> > at the tips adds great strength. The lower wing is totally fl
at with > > no dihedral making it easy to build. The upper wing needs> > no
twist and uses 2 deg dihedral. Other advantages are much stronger > > pilo
t/passengers protection due to the cage type construction=2C> > wide tolera
nce of CG changes and greater tolerance for gusty > > conditions due to the
short wings.> > > > On the sim it is possible to take off with the stick f
ull back=2C just > > wait for rotation and the a/c will just climb away bob
bing its> > nose with full roll and yaw control. Fully aerobatic too but pi
tch > > sensitivity is a little much for landing in this mode=2C easily> >
corrected with a pitch limiter for landing. Don't see why the concept > > c
ouldn't work for crowd killers as well as the short wings> > should allow t
====================> > >
_________________________________________________________________
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