Marske Flying Wings do not stall

There is no such thing as "forward airspeed". Just Airspeed.
The speed of the air over the wing is completely independent
of ground reference points. If you want to use a ground
reference, use GROUND SPEED. Airspeed and Groundspeed
are easily confused when you try to describe things so don't take it so
hard. To use your illustration, push the nose down 100 degrees from
vertical, you are now slightly inverted and traveling backwards
over the ground. Do you now have NEGATIVE AIRSPEED?
Don't think so.............

Scott

But what happens when you cock up a chandelle and don't get the nose down
before you loose forward airspeed? Seems like negative (or backwards)
airspeed to me! 8-)

Keith

Well I have just posted the video, while I did take my time getting the aft
limit of the contorl stick it was not quite at 1 knot per second.... so I
will keep that in mind for the next session.Check out the video on the
Marske Pioneer IId page.!

-thanks
-mat

"dhb" wrote in message
thlink.net...
One of the several FAA definitions that are involved in determining stall
speeds is when the aft stick limit is reached.

Another is the FIRST time the nose starts down as you are bringing the
stick aft.

Make sure that you do this test at the official 1 knot per second entry
rate.





In article , "Marske Flying
Wings"
wrote:
I did a modest cross country in the Pioneer IId yesterday but what is
most
interesting was that I am exploring all of the flight envelope and
yesterday
was stalls. When I pulled the stick all the way back slowly I suddenly
found
that my airspeed had fallen to zero where I held it for quite some time
and
my sink rate was 100 down. And I have it on video! I did this many times
although there was tendency to turn to the left since we have a left turn
in
the glider.

The airspeed system was calibrated recently, both the airspeed instrument
and the installation, however I did not do the calibration for zero
airspeed... so it could be off slightly.

I have posted a picture on the web site showing the airspeed near zero
and
will post a video shortly.

http://www.continuo.com/marske/pione...%20pioneer.htm

This is rather a long address so if this does not work go to our web site
and find "Marske Pioneer IId"

-mat

I have been recording all of this on video to give some credibillity to
my
claims.

"spektr" wrote in message ...

Bravo.
So you are flying a glider with insufficient up elevator to cause a stall
equipped
with an airspeed indicator that doesn't register well on the low end of the
spectrum.
All wings stall when their critical angle of attack is exceeded.

All wings stall when their angle of attack is beyond the limits. But
don't put the tendency for flying wings to not stall viciously as an
attribute of insufficient elevator. If the elevator had enough
authority to hold the wing past the critical angle, nobody would have
the touch fine enough to fly it. Contrasted to the brute force system
of "conventional" designs, it takes very little to control the
attitude of the flying wing types.

A little time spent beyond the fiberglass and foam model kits might
have allowed more people to experiment with things that are
"interesting". The "Scimitar" design is a good example but those not
interested in having to actually build never found out.

There is no such thing as "forward airspeed".

All depends on where your point of referance is if the vector is positive or
negative. All of the planes I have flown had the pitot somewhere in the front
and I tend to have that stuck in my mind as the referance point. Substitute
"ground speed" solar speed or what ever speed you like but da ting duz wat is
duz G

"Bill Daniels" wrote in message
...

The Marske planform does eliminate the stall/spin as a likely source of
accidents and, apparently, without a performance penalty. In exchange for
this, it introduces another area where the pilot determined to find a way
to
crash can do so.


Bill.
Very good points made.
But the Marske planform can and has entered spins.
It may not be a likely outcome of a stall , but if you go
to the NTSB website, look for the only Monarch crash.
Jim talked this accident thru with me and they still aren't sure
how the pilot did it. The pilot stalled in the pattern, spun in
impacting the ground. I don't hold this against the aircraft,
in fact I've had talked on the phone to Mat and Jim on several
occasions about their gliders. I do like what I see and hear
and I'm probably going to build a Monarch

But back to the point............

It has insufficient elevator at low speeds to stall the aircraft.
it has a high sink rate/drag envelope when slow that is different
from most other gliders. You can train your way around these things
but the premise of the discussion , non-stallability, is incorrect.

Weve beaten the 0 airspeed thing to death.

Scott

I think it is important to understand that we did not build this Monarch F
and did not know where the CG was, what wing tips he had on it are not clear
either. We viewed the video of the flight and a wing did drop but in less
than a rotation the wing was flyiing again... but the pilot entered another.
My feeling is that the pilot froze up.... as he said himself and may have
pulled the stick all the way back and crossed the controls. I do feel he had
a very far froward CG given his weight. If the CG is far forward the glider
can be made to have a sharp break in the stall.
At any rate we could not make this happen on the Current Monarch G's. I flew
a Monarch F for a couple of seasons and it was not able to spin or stall..

When we were experimenting with the CG on the Pioneer IId we could get it
to break on a stall if the CG was too far forward.

thanks for your input.

-mat


"spektr" wrote in message
...

"Bill Daniels" wrote in message
...

The Marske planform does eliminate the stall/spin as a likely source of
accidents and, apparently, without a performance penalty. In exchange
for
this, it introduces another area where the pilot determined to find a
way
to
crash can do so.


Bill.
Very good points made.
But the Marske planform can and has entered spins.
It may not be a likely outcome of a stall , but if you go
to the NTSB website, look for the only Monarch crash.
Jim talked this accident thru with me and they still aren't sure
how the pilot did it. The pilot stalled in the pattern, spun in
impacting the ground. I don't hold this against the aircraft,
in fact I've had talked on the phone to Mat and Jim on several
occasions about their gliders. I do like what I see and hear
and I'm probably going to build a Monarch

But back to the point............

It has insufficient elevator at low speeds to stall the aircraft.
it has a high sink rate/drag envelope when slow that is different
from most other gliders. You can train your way around these things
but the premise of the discussion , non-stallability, is incorrect.

Weve beaten the 0 airspeed thing to death.

Scott

On Thu, 31 Jul 2003 17:27:46 UTC, "Marske Flying Wings"
wrote:

: No this is where you are quite wrong! There is pleanty of up elevator on the
: trailing edge of the main wing.... the air going over the top is separating
: due to the high angle of attack and this makes the elevator ineffective, so
: the nose lowers slightly and the glider picks up airspeed and it resumes
: normal flight.

Which is, effectively, exactly what he said...

: "spektr" wrote in message
: ...

: So you are flying a glider with insufficient up elevator to cause a stall

Ian

On Fri, 1 Aug 2003 02:00:17 UTC, "Bill Daniels"
wrote:

: The Marske planform does eliminate the stall/spin as a likely source of
: accidents

From what was posted here, it stalls fine but as a mushing stall
(which is exactly what I get in a K8). Just as a matter of interest,
what happens in a Marske if you stall it and then kick in a bootful of
rudder? Or stall it in a thermalling turn? Does failure to drop the
nose at stall really mean it can't spin?

Ian

--

"Ian Johnston" wrote in message
news:cCUlhtvFIYkV-pn2-EdKXeK7dL0Wj@localhost...
On Fri, 1 Aug 2003 02:00:17 UTC, "Bill Daniels"
wrote:

: The Marske planform does eliminate the stall/spin as a likely source of
: accidents

From what was posted here, it stalls fine but as a mushing stall
(which is exactly what I get in a K8). Just as a matter of interest,
what happens in a Marske if you stall it and then kick in a bootful of
rudder? Or stall it in a thermalling turn? Does failure to drop the
nose at stall really mean it can't spin?

Ian

Ian, Flying both the Pioneer 1A and the Pioneer II, I have held full rudder
through a series of stall attempts and all I got was a mushing turn. I was
never able to get anything even remotely resembling a spin departure. In
several tests I made extreme attempts to get a departure without success.
The slow flight behavior is benign in the extreme even with the CG aft of
the rear limit.

Now, lets talk about stalls. If you get a nose drop, that doesn't
necessarily mean a stall has occurred. To my way of thinking, a stall
require a substantial disruption of airflow over the upper surface of the
wing resulting in loss of lift and a departure from controlled flight.

My experience with Marske gliders is the same as other pilots in that the
ailerons remain fully effective and the elevator control retains a solid
feel. In short, the glider never departs controlled flight. What you do get
is a sharp loss of up elevator authority as the AOA exceeds a certain value
and the nose bobs down a bit. I really don't feel comfortable calling that
a stall since the airflow over the majority (probably the forward 60% of the
chord) of the wing remained attached.

Even the description, "mushing stall" seems inappropriate. The glider
doesn't even sink rapidly at minimum airspeed with the stick full back - it
just glides slowly along with all controls fully effective.

This doesn't mean you can't crash the glider - it just means you have to
work a lot harder to do it.

Bill Daniels

On Sat, 2 Aug 2003 12:49:49 UTC, "Bill Daniels"
wrote:

: My experience with Marske gliders is the same as other pilots in that the
: ailerons remain fully effective and the elevator control retains a solid
: feel.

Sounds just like a mushing stall in a Ka8!

: Even the description, "mushing stall" seems inappropriate. The glider
: doesn't even sink rapidly at minimum airspeed with the stick full back - it
: just glides slowly along with all controls fully effective.

Sounds just like a Ka8 with an elevator stop. Primary gliders used to
have these ...

Ian


--