> >> Hey Marco - I live in Golden, Colorado USA and am planning
 > >> on building this plane http://www.ligeti-stratos.com
 > >> I have scaled it up from 78 sq ft to 110 sq ft and am
 > >> planning to use this engine
 > >> http://www.woelfle-engineering.com/ at 50 hp. It is a
 > >> racing kart engine that was used in a turboed version in
 > >> 2007 to set the world powered paraglider altitude record
 > >> flying over Mt Everest
 > >>
 >
 >http://www.gknmissioneverest.com/missioneverest/themissioneverestparamotor1.asp
 > >> and http://www.gknmissioneverest.com/
 > >>
 > >> There is now an American made wankel engine that is
 > >> available in single rotor 65 hp and dual rotor 130 hp and
 > >> turbo 180 hp here http://www.rotamax.net. These are very
 > >> light engines. I'm interested in one for my Europa
 > >> kitplane. Hope this helps - good luck!
 > >>
 > >>
 > >> Glenn Crowder
 > >
 > >
 > >Dear Glenn
 > >
 > >thank you for the links, i will enquiry on the
 > >"affordability" of rotamax (even if the 65 is a bit small
 > >and the 130 is overrated for my application) and know more
 > >on the go-kart woelfle engines, this latter is good to know
 > >for thinking on other projects but really too small for my
 > >application.
 > >
 > >concerning the Ligeti Stratos, it is a very interesting
 > >policy they have done with their "open source" thing.
 > >concerning the machine, it is really a piece of elegance! by
 > >the way, why are you increasing the surface? are you
 > >planning to make it a twin seater? other tweaks? i'm
 > >curious.
 > >i read about its flight control technique, one can have some
 > >fun with it :-)
 > >
 > >thank you again for the links
 > >
 > >mrk
 > >
 > >-------
 > >Aerial Creatures & Cognitive Integration
 > > www.karenfuxia.com
 >
 > Glenn,
 >
 > This plane looks like a good candidate to go thin film PV or PV battery
 > electric. Check out what Sonex has done with their electric plane.
 >
 > Doug in Japan
 >
 > Doug, I mailed your other pump today.
 >
 > Paul Lamar
 >
   Hi Marco - my summertime density altitude norms are between 7000 to 9000
ft on a hot day plus no matter how much I diet and exercise can't seem to
break 220 lbs!  A buddy has a Koenig 3 cyl 24 hp powered Swift glider (same
engine as used on the original Ligeti-Stratos) and even on a 4700 downhill
runway climbs sluggishly (dangerously?).  I have modeled the Stratos in
X-plane 8 and have it flying very well I think.  It pretty much flies itself
and is stall/spin proof unless you hold one of the tip rudders at full
deflection.  I have redesigned the control surfaces for ease of building and
have all surfaces on the forward (lower) wing.  The main wing is totally
clean with only the tip rudders.  The lower wing is totally flat with no
twist and the main wing has 3 deg dihedral with no twist.  The original
airfoil was a Wortmann FX series but seems to have undesireable negative
pitching moments in the sim at higher speeds.  The NACA 23012 low moment
airfoil only gives up a negligible amount of lift in return for no negative
pitching at high speeds.


I would be happy to send you the X-plane 8 model
to try.  Would love to get any feedback.  The ailerons work right up to
stall speed where they get a bit mushy but you still have plenty of
authority with the tip rudders, rolling nicely even below stall.  I got rid
of the flaps as the a/c flies very slowly without them but needed a
bellyboard to degrade the 20/1 glide for landing.  Much simpler and lighter
than four separate flaps.  Very wide speed range with a 50 hp engine, WOT at
160 kts, stall at 40.  The stall is just a nose bobble and is possible to
take off with the stick full back at full power with the a/c rotating and
climbing out with just a mild pitch oscillation with full roll control.

Marco I think the only way to get near 100 hp at the weight you need is to
copy the Everest engine using the Rotrex C15 lightweight 6 lb supercharger.
BMW uses this supercharger on one of its motorcycles.  This gave 85-95 hp at
38 kg for the Everest flight.  http://www.rotrex.com

@Doug   The PV electric is interesting but would only provide marginal
recharge in flight.  Most recharging would have to be done on the ground and
I can't really see leaving this thing out on the ramp waiting hours for a
free charge!  However, the new Lithium Ion Phosphate technology would allow
10 minute recharges if you had a high amp charger! Here's an interesting LiP
pack here, 12.8 V 16 ah pack at 3.8 lbs and puncture proof.  I'm looking at
a way to use this pack in my Europa to replace my 23 lb Concorde gel cell
but it requires a constant current 14.4v till charged.
http://store.peakbattery.com/lfp200es-128v-16ah.html

    Glenn

Glenn,


Yes you are right on the limitation of PV or even battery powered plane.
I was thinking motor glider as in self launch.  20-1 in a sail plane is
not stellar now-a-days but good enough to catch a thermal. A design mod
oriented as a glider would be  of interest.

Thanks for the battery info.  Concorde Inc. is working on a LI battery
now for aircraft but they haven't shown it to us (their Japanese
dealer) yet.  We import and use their mil. spec AGM Lifeline series for
alternative energy installations.

Correct, Your present  20 amp/hour battery is 22lbs heavy but dirt simple
to regulate.  Have you investigated the alternator and other hardware
weight and charging characteristics needed to keep the newer LIP battery
filled?

In addition to what the manufacturer states as puncture proof, what ever
that means, consider putting this battery in a water proof, moisture
free container.

My company has presently developed a LiH capacitor of 100 farad used for
absorbing peak wind gusts that push our wind turbine from normal 1Kw
output to up to 4kW.  It is used between the turbine and the inverter
when feeding electricity into the grid. Two months ago a capacitor unit
failed.  Here is what happened.  The factory had  one faulty ultrasonic
welder on the line and unfortunately they didn't do enough full charge
operational testing quality control on each and every cell manufactured.
One of cells leaked LIH  out into the metal capacitor containment box
and reacted with the small amount of condensation found there.  High
school chemistry explains what happens next.  Simply, the rapid release
of hydrogen and heat.  The flash fire only fried the electronic
regulating circuit but the energy potential of that several grams, if it
found enough water to react with, would have have made a powerful
B#O#%O!B.   Needless to say we had to recall and replace over 100 units,
not being sure which, if any others,  might be defective as well.
This is also why if the fire department is called to put out a car fire
containing sodium or lithium batteries they will NOT spray water on it.
If it is in the garage then they will let the house burn down. Ask Ford
motor company.

Very interesting results with X-plane. Is it windows based?


Doug in Japan