Japanese plane - shrouded pusher w/winggrids

Earlier, wrote:

OK.

How are they getting an increase in L/D while decreasing span and
adding drag?

(And before the serious flames begin, neither I nor they are selling
anything.)

The short answer is, they're not. Their verbiage and treatises dance
around it by carefully comparing apples to oranges.

wrote ...
How are they getting an increase in L/D while decreasing span and
adding drag?

The only way for this system to do what they claim is they would have to add
energy to the airflow. Perhaps they just forgot to tell us about a small
embedded jet engine.

Rich

These guys selling snake oil too?

http://www.star-tech-inc.com/papers/aiaa/aiaa.pdf

http://tinyurl.com/g66ln

http://jeb.biologists.org/cgi/reprin...lcode=je xbio

Alsio
SPEDDING, G. R. (1992). The aerodynamics of flight. In Mechanics of
Animal Locomotion (ed. R. McN.
Alexander). Berlin: Springer-Verlag.

SPILLMAN, J. J. (1987). Wing tip sails; progress to date and future
developments. Aeronaut. J. 91,
445-453.

Or did we reach the totality of knowledge on wing tip design with
Whittman's experiment?

Earlier,

Richard Riley wrote:

These guys selling snake oil too?

http://www.star-tech-inc.com/papers/aiaa/aiaa.pdf

http://tinyurl.com/g66ln

http://jeb.biologists.org/cgi/reprin...lcode=je xbio
...

Not at all. They make a convincing case that carefully-implemented
multiple element winglets can reduce induced drag so as to improve best
L/D over some range of Cls, especially for wings with low aspect ratio.
What they don't try to do is sell such configurations as a panacea, a
"substitute for span."

As all good sailplane pilots know, the only substitute for span is
talent. The difference between the two is that you can _buy_ span.

Thanks, Bob K.

Bob Kuykendall wrote:
Earlier,

Richard Riley wrote:


These guys selling snake oil too?

http://www.star-tech-inc.com/papers/aiaa/aiaa.pdf

http://tinyurl.com/g66ln

http://jeb.biologists.org/cgi/reprin...lcode=je xbio
...


Not at all. They make a convincing case that carefully-implemented
multiple element winglets can reduce induced drag so as to improve best
L/D over some range of Cls, especially for wings with low aspect ratio.
What they don't try to do is sell such configurations as a panacea, a
"substitute for span."

As all good sailplane pilots know, the only substitute for span is
talent. The difference between the two is that you can _buy_ span.

Thanks, Bob K.

While there was some discussion about heavy jet wings, the data in the
paper indicated that the tests were performed at very low Reynolds
Numbers - 161K to 300K.

Our light experimental usually run at least 3,ooo,ooo.

They are studying Eagle wings - not 747's...

Richard

Richard Riley wrote:
These guys selling snake oil too?

http://www.star-tech-inc.com/papers/aiaa/aiaa.pdf

http://tinyurl.com/g66ln

http://jeb.biologists.org/cgi/reprin...lcode=je xbio

Alsio
SPEDDING, G. R. (1992). The aerodynamics of flight. In Mechanics of
Animal Locomotion (ed. R. McN.
Alexander). Berlin: Springer-Verlag.

SPILLMAN, J. J. (1987). Wing tip sails; progress to date and future
developments. Aeronaut. J. 91,
445-453.

Or did we reach the totality of knowledge on wing tip design with
Whittman's experiment?


Wittman's Wonderful Wing Widget

Yep, I think so!

To my knowledge, this is the only light plane wing tip design that makes
a measurable difference in flight.
If you can measure it, it's there!

Best I can do for now is a pic of a (modern) all wood outer panel -
before installing the top skin. It's a work in progress, but gives
an idea of the shape.
http://home.earthlink.net/~tp-1/w10-tip.jpg
The originals were brazed up steel and fabric. (yeah right!)


The Unofficial Tailwind Page is located at:
A lot of info there - including flight reports and old reprints.
http://www.chlassociates.com/Aviation/Tailwind.htm


I had a link to the '05 race winner, (210 mph on 160 hp?) but I can't
find it right now. Pretty thing!


Richard

(X the X to reply)

("Richard Lamb" wrote)
http://home.earthlink.net/~tp-1/w10-tip.jpg
The originals were brazed up steel and fabric. (yeah right!)


The Unofficial Tailwind Page is located at:
A lot of info there - including flight reports and old reprints.
http://www.chlassociates.com/Aviation/Tailwind.htm


home.earthlink.net/~tp......... link doesn't work for me.

Lose the capital "T" in Tailwind for your link to work:
http://www.chlassociates.com/Aviation/tailwind.htm
This link works.

http://www.chlassociates.com/Aviation/
Or play around in here


Montblack

Montblack wrote:
("Richard Lamb" wrote)

http://home.earthlink.net/~tp-1/w10-tip.jpg
The originals were brazed up steel and fabric. (yeah right!)


The Unofficial Tailwind Page is located at:
A lot of info there - including flight reports and old reprints.
http://www.chlassociates.com/Aviation/Tailwind.htm



home.earthlink.net/~tp......... link doesn't work for me.

Lose the capital "T" in Tailwind for your link to work:
http://www.chlassociates.com/Aviation/tailwind.htm
This link works.

http://www.chlassociates.com/Aviation/
Or play around in here


Montblack


Try it now?
http://home.earthlink.net/~tp-1/w10-tip.jpg

Montblack wrote:

Lose the capital "T" in Tailwind for your link to work:

http://www.chlassociates.com/Aviation/tailwind.htm
This link works.

http://www.chlassociates.com/Aviation/
Or play around in here


Montblack


Again. Thanks.
I might finally have it worked out.

http://www.home.earthlink.net/~tp-1/w10-tip.jpg
Wittman W-10 all wood wing tip.


http://www.home.earthlink.net/~tp-1/
This should give the folder index
or start a web page "index.htm" - if one existed?



Richard

"Buttercup"

Steve's "parts hauler"
http://www.chlassociates.com/Aviation/buttercup.htm

The second (of 3) pictures shows Steve examining the unique
Leading Edge flap on Buttercup.

Leading edge flaps are effective when used in conjunction
with a corresponding trailing edge flap.

Buttercup had longer wings - and longer trailing edge flaps.

On a Tailwind style wing, half the TE flaps - the other half ailerons.

So, to spread the effect further out on the wings, droop the ailerons
as the flaps go down?



Richard