Soaring vs. Flapping

"Corrie" wrote in message
om...
"A human being should be able to change a diaper, plan an invasion,
butcher a hog, conn a ship, design a building, write a sonnet, balance
accounts, build a wall, set a bone, comfort the dying, take orders,
give orders, cooperate, act alone, solve equations, analyze a new
problem, pitch manure, program a computer, cook a tasty meal, fight
efficiently, die gallantly. Specialization is for insects."
- Robert Heinlein, "The Notebooks of Lazarus Long"

One of the best quotes ever :-)

Along with the near corollary:

An expert (specialist) is someone who knows more and more about less and
less until they know absolutely everything about nothing at all!

Eric

"Robert Bonomi" bonomi@c-ns. wrote in message
hlink.net...
In article ,
Corrie wrote:


"Eric Miller" wrote in message
v.net...

Water and air are both fluids, but with densities of different
magnitudes.
I'd think that you'd want to develop your idea to work in water before
you
tried the thinner and vastly more difficult fluid of air.

If air were more dense or gravity was less...
BTW I remember something similar in a Heinlein book, maybe "The Moon Is
A
Harsh Mistress".

I knew I'd come across it somewhere!

Heinlein's most detailed discussion of man-powered flight is in "Podkayne
of
Mars". The Icarus variety -- i.e. strap on wings that you flap.

ITYM "The Menace from Earth". A short story generally found in the
compilation of the same name.
Still, Holly Jones does bear some resemblance to Podkayne...

Tim Ward

Before you can "think outside the box", you have to have some idea of where
the box is.

What box?

Patrick

One issue with your wing design is that the sphericon is a geometric
solid.

I meant for the design to use only the edges of a sphericon, connected
by a springy structure that would allow them to be scissored back and
forth. The structure could be draped in foam the way different shaped
bubble wands hold minimal surface bubbles.

perhaps some utility in mechanical
devices - wobbling bearings, maybe?

I built this machine (sphericon machine)
http://patricktimony.tvheaven.com/photo.html
on a 3D printer. When you spin the central rod it makes the handles
wobble back and forth which could be turned into pistoning. I thought
it might be useful in a conventional ornithopter but I'm sure theres a
gear out there that does this already.

the seemingly random inclusion of the golden mean as
one of the concepts.

I got this shape from looking at oar blade designs. See:
http://www.concept2.com/products/oars/oartesting2.asp
Also it's easy to test using cardboard. A 3x5 rectangle just feels
like the best air scoop - it catches the most air.

I'd think that you'd want to develop your idea to work in water before you
tried the thinner and vastly more difficult fluid of air.

I think a ray-shaped diving suit, made of sealed foam and with
knife-like but really controlable edges would move really well.

"Model Flyer" wrote in message
...

Eric, that couldn't be truer, I know everything about the screw I'm
holding in my hand, I know it length, diameter, pitch of thread, even
the material it's made out of, however, I know absolutly nothing
about where the damned thing goes!!!!!!
--
Cheers,
Jonathan Lowe

So basically, what you're saying and what I'm hearing is... you're screwed!

Eric big grin

"Patrick Timony" wrote
I think a ray-shaped diving suit, made of sealed foam and with
knife-like but really controlable edges would move really well.

What you (or I) think doesn't matter... that's why we experiment!

Eric

"patrick timony" wrote
That makes sense. I trust Leonardo. I have a feeling that he didn't
think any wrong thoughts. He wasn't a speculator as much as an
instrument that allows you to see possibilities. And his designs and
Otto Leilenthal's are so beautiful compared to anything since, they
must be right.

Functional and useful has a beauty all its own.
Beauty plus useless is still useless =D

Remember, Leo never got off the ground and Otto provided incorrect
coefficients of lift (which is why the Wrights had to build a wind tunnel)
AND he died in a crash after too few (very short) gliding flights.

As someone else recently quoted Igor Sikorsky here on RAH: "There are good
designers with bad designs and bad designers with good designs. If we all
flew our own designs, there would soon be only good designers with good
designs." Survival of the fittest with a vengeance!

BTW did anyone else catch the First in Flight special showing (and still
being re-shown) on the Discovery Channel?
Apparently the Wrights' propellers were 80% efficient in converting engine
HP into thrust compared to the 40% of their contemporaries.
Meanwhile, modern propellers are only 85% efficient. I find that to be
absolutely mind-blowing.

Eric

(patrick timony) wrote in message . com...
soaring flight is quite common in nature.

I agree. I was thinking in terms of the evolution of flight or of
propulsion - that soaring would be further down the line than flapping
(undulating), and thus rarer, because everything had to flap before it
could soar.

If you believe the paleontologists, they say that the pterodons did
not flap - they dropped from cliffs and soared. Archaeopterix may
have flapped, but it didn't have much of a breastbone to support
flapping muscles.


Wing warping isn't flapping, it was a way to effect directional
changes in flight by changing the shape of the wing.

Wing warping is the very beginning of flapping. At this wing warping
page: http://wright.nasa.gov/airplane/warp.html if you move the java
applet slider back and forth you can see how wing warping could be
propulsive. That's the same motion that many animals use to propel
themselves; they don't separate the steering from the acceleration,
it's just one fluid motion.


That's an inaccurate simplification. To provide lift and propulsion,
the wing has to move back and down, not just twist about its axis.
Basic physics.

Yes, they did enforce their patent with vigor and largely succeeded
in the
USA until WW I, effectively hampering aircraft development.

ailerons worked better.

It sounds like this patent forced the industry to build bigger faster
planes that soar instead of smaller and slower planes that warp or
flap.

Nonsense. Their vigorous enforcement spurred the development of
ailerons, not gliders.


People made bird-like flapping designs for manned flight because they
saw birds flying and thought that was the way man should fly as well.

That makes sense. I trust Leonardo. I have a feeling that he didn't
think any wrong thoughts. He wasn't a speculator as much as an
instrument that allows you to see possibilities. And his designs and
Otto Leilenthal's are so beautiful compared to anything since, they
must be right.

As t'was said: Beautiful plus useless equals useless. Leo's
aeronautical designs show a fine ignorance of the hard realities of
power loading. His helicopter and ornithopter may be pretty, but they
cannot be made to work as designed. Physics trumps beauty *every*
time. Just look at the F-4, B-52, and A-10. Ugly as a pimple on a
warthog's butt. But they WORK.

Earlier, (Corrie) wrote:

...
Beautiful plus useless equals useless...

You just made this thread worth my time. Thanks!

Bob K.
http://www.hpaircraft.com/hp-24