Subject: Coaxial Canard STOL Research
From: Rotary Engine
Date: 8/24/2007, 11:47 AM
To: AARotary Engine


 Here is a great little economy/beginner R/C helicopter with Coaxial
rotor system.  It is stable
as hell.  A monkey could fly this thing.  If you get in trouble, all you
have to do is let go of
the controls and it will automatically go into a hover.  Just don't kill
the throttle.  These little
coaxial helis are much more stable than the full CCM heads on the
upgrade helis.  Watch the
video at the bottom of the page!

_http://www.espritmodel.com/index.asp?PageAction=VIEWPROD&ProdID=4364_
<http://www.espritmodel.com/index.asp?PageAction=VIEWPROD&ProdID=4364>


> Date: Fri, 24 Aug 2007 09:14:34 -0700
> From: rotaryeng@earthlink.net
> To: rotaryeng@earthlink.net
> Subject: Coaxial Canard STOL Research
>
>
>
> >I liked this practical configuration so much I added it to my web site:
> > http://www.rotaryeng.net/STOL.html
> >
> > Thanks to all the people that uploaded ideas and suggestions.
> > Especially Roger Parker for displaying his STOL airplane at the
Camarillo
> > air show and inspiring me.
> >
> > Honda is getting into personal jets. Mazda could build something
> > like this almost anybody could afford. People have dreamed
> > about an airplane that can take off in their back yard and fly
> > for a 1000 miles for the last 100 years. The Mazda rotary engine and
> > carbon fiber could make that dream come true.
> >
> > Paul Lamar ...No rotor no motor.
>
>
> Paul,
>
> You need to talk to this guy:
> http://www.amvaircraft.com/html/new_developments.html . Atilla
(that's his
> real name) was using a turbocharged 13B engine in his prototype and
he was
> hovering when he burned it up. He's now thinking about installing an
> Allison 250 (Rolls Royce) turboshaft. I was looking at those aluminum
> housings from Racing Beat today and I'm thinking a turbocharged 20B
with the
> aluminum details might be the ticket for this aircraft.
>
> By the way, forget about that rotating cockpit. I work at the company
that
> built the more successful of those two "pogo" type prototypes. If you
> really want to do that, make the airplane(?) a pusher, do vertical
with the
> pilot standing up (Hiller did this) and have the pilot prone horizontal
> flight (this was successfully done by both Northrop and the Horton
Brothers
> as well as the Wright Brothers). You could also have the engine
behind your
> feet and use a shaft to drive rotors in the nose but you would have to be
> careful about forward visibility. Someone is now building a UAV in
the same
> configuration as the Lockheed XFV-1 but they are using a computer for
> landing that didn't exist in the 50's. Check this out:
> http://www.unrealaircraft.com/gravity/xfv1.php . In any case, a
design like
> this isn't too unreasonable especially since ballistic parachutes
like the
> one in the Cirrus are readily available.
>
> Steve Brazil
>
> Thanks for the suggestion Steve. A prone pilot sounds like a great idea
> if he could look straight down as well as up. TV view I am not so sure
> about. How do you land if you have total electrical failure?
>
> A pusher would require a duct I suspect which is very inefficient
> in high speed forward flight. Also the canard is much more stable
> on the ground than a conventional airplane like the XFV1 in windy
> conditions.
>
> Also I use helicopter like cyclical pitch controls to
> get around the XFV1 hover control problems. A helicopter
> will auto rotate to a safe landing in the event of an engine failure
> or running out of fuel for that matter.
>
> Here are some pictures I took of the Amvair aircraft at OSH
> in 2003. It never flew as far as I know.
> The request for investment always raises a red flag in my mind.
> As far as I can tell from looking at it the hover controls
> are inadequate. The engineer was also naive about tuning a
> 13B turbo rotary engine allowing it to detonate and destroy itself.
> Not a confidence inspiring event. Small turbo prop engines are
> too expensive and fuel hungry.
>
> -----------------------------------------------------------------
>
> Here is the Convair version. It too had hover control problems.
> Using helicopter cyclical pitch control removes 90% of the
> technical risk. Many coaxial counter rotating blade helicopters
> have flown and flown well.
>
> -----------------------------------------------------------
>
> Web sites for history back ground.
> http://www.vstol.org/wheel/wheel.htm
> http://www.kulikovair.com/Coaxial.htm
> http://aviation-history.com/garber/vg-bldg/hiller_copter-1_f.html
> http://www.gyrodynehelicopters.com/coaxial_benefits.htm
> http://www.kamov.ru/market/news/petr11.htm
> http://www.kamov.ru/market/encycl/coahe.htm
> http://www.yoshine.com/home.php
> EzyCopter employs a Coaxial Drive System (CDS) coupled with
> twin rotary engines and linked with innovative collective and cyclic
controls.
> With the benefits of simpler design, lighter weight, more balanced
and torque-free
> hovering capability, safety features of EzyCopter will exceed all
expectations.
> While compact in size, the EzyCopter is the only recreational coaxial
helicopter
> equipped with twin rotary engines, twin articulated rotors, four
rotor blades,
> and correlated cyclic and collective controls, making EzyCopter
easier and safer
> to fly!
> http://www.nasm.si.edu/research/aero/aircraft/hiller_xh44.htm
> http://www.helis.com/Since80s/h_ka50.php
> http://en.wikipedia.org/wiki/Coaxial_rotors
>
> "A principal disadvantage of the coaxial rotor design is the
increased mechanical
> complexity of the rotor hub - linkages and swashplates for two rotor
discs need
> to be assembled around the rotor shaft, which itself is more complex
because of
> the need to drive two rotor discs in opposite directions. In an
elementary
> engineering sense, the coaxial rotor system is more prone to failure
because
> of the greater number of moving parts and complexity, though the
engineering
> tolerances in aerospace are usually sufficiently precise to mitigate
this somewhat."
>
>
> Paul Lamar ...No rotor no motor.


 Here is a great little economy/beginner R/C helicopter with Coaxial
rotor system.  It is stable
as hell.  A monkey could fly this thing.  If you get in trouble, all you
have to do is let go of
the controls and it will automatically go into a hover.  Just don't kill
the throttle.  These little
coaxial helis are much more stable than the full CCM heads on the
upgrade helis.  Watch the
video at the bottom of the page!

_http://www.espritmodel.com/index.asp?PageAction=VIEWPROD&ProdID=4364_
<http://www.espritmodel.com/index.asp?PageAction=VIEWPROD&ProdID=4364>


glenn crowder


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