Why Airplanes Fly - Voids Above A Planar Sheet

On Thu, 4 Oct 2007 14:36:55 -0700, "Gatt"
wrote:


"Le Chaud Lapin" wrote in message
ups.com...

So yes, I believe this experiment illustrates an important phenomenon
in aerodynamics. It is not the only phenomenon that plays a role, but
it has one, nevertheless. The decriptions of lift that I read in
flight books seem to ignore it.

Subsequently, all the airplanes are falling from the sky.

I recommend building an airplane sometime. The ultimate way to prove your
theory is to be like the Wright Brothers; build it and fly it.

Folks on this forum have logged hundreds of thousands if not millions of
collective hours and all of them have put their asses on the line based on
the aerodynamic principles in books, so you're not going to get much respect
here if you want everybody to do experiments just to discuss to your
otherwise-unproven theories. Some people here have built their own planes,
or engineered airplanes, or maintained them so -their- science is
sufficiently proven. All the discussions and textbooks and usenet theories
in the world aren't worth your first solo flight around the pattern. That
demonstrates that the aerospace engineers proved their wing design and that
the pilots here proved their ability to manipulate that technology. That's
what it takes.

About once a month somebody comes in here and wants to talk about how
aerospace science is all wrong but the thing is, none of 'em ever seems to
have flown an airplane. If you don't do their math for them just the way
they want you to, however, somehow it's all the pilots and plane builders
out here who don't know what they're talking about.

I think your theory would be great put into practice on an experimental
aircraft. I promise you, if you fly it they will come. Best of luck to
you.

-c


I will first admit I haven't done the experiments outlined in Lapin's
posts. I will second admit that airplanes do fly. Thirdly I will
admit there are many very good reference books on "why" airplanes fly.
The key word here is "why". The fact that people can design and build
a machine that flies, means they have mastered the elements of design
that allow an aircraft to fly. It doesn't mean they know "why" it
flies. There are accepted theories, disproved theories, questionable
theories and unproven theories, but they are all theories.

Le Chaud Lapin has posted some experiments that in their present form
exhibit some interesting characteristics. Whether or not these
characteristics can be extrapolated to winged aircraft remains to be
seen. Certainly further, much more complex, testing would have to be
done. However, that fact should not provoke the kind of vitriolic
attacks I've seen in this forum. Just because someone posts something
outside the box of conventional thinking is no reason to attack them.
Ron Kelley

Le Chaud Lapin wrote in
ups.com:

On Oct 4, 5:20 pm, "Gatt" wrote:
"Le Chaud Lapin" wrote in
ooglegroups.com...
Oh, nevermind, everybody. It's the same guy with a new handle.
It's

My handle has been the same for over a decade.

Jeppesen, and, do you have any idea how many people are successfully
flying with what they learned from the Jeppesen books? Are you one
of them?

Not yet. I will continue to study my Jeppesen book. That does not
mean that I will blindly accept everything I read.


Wel, if you do ever leave your bedroom and take a flying lesson that will
turn out to be some CO2 pumped into the atmosphere for nothing.
At least your instructor will make enough to supersize off you.


Bertie

On Oct 5, 12:03 am, Ron wrote:
I will first admit I haven't done the experiments outlined in Lapin's
posts. I will second admit that airplanes do fly. Thirdly I will
admit there are many very good reference books on "why" airplanes fly.
The key word here is "why". The fact that people can design and build
a machine that flies, means they have mastered the elements of design
that allow an aircraft to fly. It doesn't mean they know "why" it
flies. There are accepted theories, disproved theories, questionable
theories and unproven theories, but they are all theories.

Le Chaud Lapin has posted some experiments that in their present form
exhibit some interesting characteristics. Whether or not these
characteristics can be extrapolated to winged aircraft remains to be
seen. Certainly further, much more complex, testing would have to be
done. However, that fact should not provoke the kind of vitriolic
attacks I've seen in this forum. Just because someone posts something
outside the box of conventional thinking is no reason to attack them.
Ron Kelley

Thanks Ron.

Given the ratio of ad hominem attacks I have experienced in my first
few days here versus true exploration, I was beginning to wonder if
the 10 people or so who have been responding are representative of
this group, since they do seem to generate the most messages. I saw
your post about 30 seconds after and concluded that perhaps they are
not.

-Le Chaud Lapin-

Le Chaud Lapin wrote:
Given the ratio of ad hominem attacks I have experienced in my first
few days here versus true exploration, I was beginning to wonder if
the 10 people or so who have been responding are representative of
this group, since they do seem to generate the most messages. I saw
your post about 30 seconds after and concluded that perhaps they are
not.

First, I finally found time to read your initial post to this thread. It is
true that all the explanations you've read over the years are not quite
right - that is due to the nature of fluid dynamics. Except for some
trivial examples, the mathematics can't be solved except by numeric
approximation methods. The Bernoulli theorem for example assumes a pre-
existing streamline. It does not actually provide the all-important
streamlines! Otherwise the theorem does take account of all the applicable
conservation laws - but not in a form that can shed much insight into lift
(IMHO).

As to the response you've seen - well, I have some theories but if they are
correct there is nothing I can do, except possibly indirectly. Such as
making this post.

I think for the purposes of piloting that one does not need to know the
Navier-Stokes equations. Because quite honestly the real explanation of
lift is to be found in the differential equations (or integral form)
governing mass continuity, momentum, and energy. All those simple
explanations are just that - simple and obviously incomplete. Rest assured
you're correct in your observations on the inadequate explanations - but
don't make the mistake of assuming a simple _and_ accurate one must exist,
if only you think hard enough on it.

If you are interested in some books on the subject I'd be happy to make
some suggestions.

Le Chaud Lapin wrote in news:1191561472.221396.70520
@w3g2000hsg.googlegroups.com:

On Oct 5, 12:03 am, Ron wrote:
I will first admit I haven't done the experiments outlined in Lapin's
posts. I will second admit that airplanes do fly. Thirdly I will
admit there are many very good reference books on "why" airplanes fly.
The key word here is "why". The fact that people can design and build
a machine that flies, means they have mastered the elements of design
that allow an aircraft to fly. It doesn't mean they know "why" it
flies. There are accepted theories, disproved theories, questionable
theories and unproven theories, but they are all theories.

Le Chaud Lapin has posted some experiments that in their present form
exhibit some interesting characteristics. Whether or not these
characteristics can be extrapolated to winged aircraft remains to be
seen. Certainly further, much more complex, testing would have to be
done. However, that fact should not provoke the kind of vitriolic
attacks I've seen in this forum. Just because someone posts something
outside the box of conventional thinking is no reason to attack them.
Ron Kelley

Thanks Ron.

Given the ratio of ad hominem attacks I have experienced in my first
few days here versus true exploration, I was beginning to wonder if
the 10 people or so who have been responding are representative of
this group, since they do seem to generate the most messages. I saw
your post about 30 seconds after and concluded that perhaps they are
not.

Except we both know that isn't what you are doing.


Bertie

On Oct 5, 1:11 am, Jim Logajan wrote:
Le Chaud Lapin wrote:
I think for the purposes of piloting that one does not need to know the
Navier-Stokes equations.

That's true.

Because quite honestly the real explanation of
lift is to be found in the differential equations (or integral form)
governing mass continuity, momentum, and energy.

Yes, I agree.

All those simple
explanations are just that - simple and obviously incomplete. Rest assured
you're correct in your observations on the inadequate explanations - but
don't make the mistake of assuming a simple _and_ accurate one must exist,
if only you think hard enough on it.

I never thought that my explanation was complete or accurate. I
offered it because, IMO, it has a sificant influence on airfoil
dynamics. But after reading several books that ignore the partial
vacuum, and one book that was wrongly employing Newton's thereom...
[which is intolerable on any grounds, let alone aerodynamics], I had
to read more.

In his book, "The Proficient Pilot", on page 8, Barry Schiff writes:

"There is, for example, this amusing fable: 'Air flowing above the
wing has a greater distance to travel (because of camber) than air
flowing beneath the wing. Therefore, air above the wing must travel
faster so as to arrive at the wing's trailing edge at the same time as
air flowing underneath. This is pure nonsense."

In his book Learning to Fly With Rod Machado, on page 70, Rod Machado
writes:

"Because air flowing over the wing bends, it is forced to travel a
greater distance than the air flowing underneath. Because it travels a
greater distance, the bent air must move faster on its journey over
the wing. It's this relative increase in wind speed above the wing
that lowers pressure and productes lift."

Since I was new to piloting, I asked a few pilots if they understood
aerodynamics about an airfoil, and they all said yes. The reason they
gave is the one that Rod Machado gave. I asked the older pilots if
they knew who Barry Schiff was, and they said yes. I asked them if
they realized that Barry Schiff did not think that was the reason, and
they said I was mistaken, that Barry Schiff would never be as confused
as I seemed to be about flying. I asked them if they knew who Rod
Machado was. They said yes. I asked them if they thought that Rod
Machado and Barry Schiff would agree. They said yes. I asked them if
they were 100% certain, and they said yes.

Thus began my earnest interest in aerodynamics. I had always been
interested in flying, but this accelerated the interest quite a bit.

I took a sheet of paper and blew over it, the trick that we've all
done, and it went up of course, but I suspected that the reason it
went up was not the reason that was being given by so many people.

I visited a few aero/astro departments online, and while no one is
going to argue with the mathematics of field theory...I did get the
feeling that there were experts in the field saying the opposite
things. So before digging into the math [afterall, there is nothing
wrong with math], I decided to refresh my understanding of Bernoulli's
theorem from my old physics book, and while reading that book, it
occured to me that Barry Schiff's view is more likely right than
not...that is, until I read his explanation of relationship between
Newton and downwash on the next 2 pages of his book. I found a couple
of other books that gave the explanation of downwash that was
similar. Most importantly, I also notice that there was a ***HUGE***
amount of hand-waving going on, far more than one would expect in a
field that has been researched for over a century. I still need to
find a book that I can trust.

I went to the WWW and started reading more aero-astro excerpts, and
concluded that not only is theory still in flux, the experts do not
even agree on the basics. The very basics. Huge amounts of money had
been spent on wind-tunnels. But after all that, I could not get two
experts to agree on the basics. And this was a not simply a matter of
different styles, using integral instead of differential form of
equations, for example, or, deciding where to put a constant, as we
electrical engineers do in our expressions of the Fourier
integrals...there was *fundamental* disgreement about what causes lift
on an airplane.

I asked one of the pilot's again..."How sure are you that the aviation
world understands the basics?" He said he was very sure. He started
rattling off things about NASA.

I begin to imagine airflow over a wing and concluded that pinching at
front of wing must be very important, more important than one would
think, reading the explanations. I also concluded that a glider
should have wings that are very long but with a short cord, which aslo
turned out to be true. I then revisited my physics book...and it
_appeared_ that the application of Bernoulli to flying is wrong in
many contexts, but I decided to not discuss that just yet because it
would be too controversial.

I ask one of the pilots if he thought rarefication had anything to do
with it. He said, "No, it's all Bernoulli." I asked him what would
happen if I did the paper experiment, the one mentioned in my OP, and
he did not know, but said it does not matter because a piece of paper
is not a wing and it does not fly through the air. I asked him if he
understood why the paper would move, and he said, again, it does not
matter. I asked him if he saw any relation between my paper experiment
and the movement of a airfoil, and he said, finally, no, there is
none, because it is all Bernoulli.

I asked a CFI one last time, and he too said it was all Bernoulli,
precisely the argument that Barry Schiff refutes in his book.

So I started imagining, with no mathematics, what goes on with fluids
around surfaces, which lead me to these various experiments.

If you are interested in some books on the subject I'd be happy to make
some suggestions.

Sure.

-Le Chaud Lapin-

"Ron" wrote in message
...

However, that fact should not provoke the kind of vitriolic attacks I've
seen in this forum. Just because someone posts something
outside the box of conventional thinking is no reason to attack them.

The same person posted the same sort of stuff a month or so ago under a
different name, and hasn't acknowledged that he's the same guy.

The vitriol is because it's intellectually dishonest to come in and approach
the group as if you're new to the discussion, and then make reference to
something from a thread that was discussed a month ago.

Additionally, there's a difference between coming in and posting out of the
box versus coming in and suggesting that all the textbooks are wrong. If he
wants less vitriol he'll approach our common understanding of aerodynamic
science with a little more respect when among our own community.

-c

Le Chaud Lapin wrote in
oups.com:

On Oct 5, 1:11 am, Jim Logajan wrote:
Le Chaud Lapin wrote:
I think for the purposes of piloting that one does not need to know
the Navier-Stokes equations.

That's true.

Because quite honestly the real explanation of
lift is to be found in the differential equations (or integral form)
governing mass continuity, momentum, and energy.

Yes, I agree.

All those simple
explanations are just that - simple and obviously incomplete. Rest
assured you're correct in your observations on the inadequate
explanations - but don't make the mistake of assuming a simple _and_
accurate one must exist, if only you think hard enough on it.

I never thought that my explanation was complete or accurate. I
offered it because, IMO, it has a sificant influence on airfoil
dynamics.



Ooow! Write Nasa quick! Your research is obviously going to enable the next
critical leap in aeronautical sciences!


Bwawahwhhahwhahwhahwhahwhahwhahwhahawh!


Bertie

On Oct 5, 10:02 am, "Gatt" wrote:
The same person posted the same sort of stuff a month or so ago under a
different name, and hasn't acknowledged that he's the same guy.

The vitriol is because it's intellectually dishonest to come in and approach
the group as if you're new to the discussion, and then make reference to
something from a thread that was discussed a month ago.

I have never assumed any other alias on USENET other than the one that
I a currently using in the 20 years I have been using the Internet.

-Le Chaud Lapin-

On Oct 5, 10:30 am, Le Chaud Lapin wrote:
On Oct 5, 10:02 am, "Gatt" wrote:

The same person posted the same sort of stuff a month or so ago under a
different name, and hasn't acknowledged that he's the same guy.

The vitriol is because it's intellectually dishonest to come in and approach
the group as if you're new to the discussion, and then make reference to
something from a thread that was discussed a month ago.

I have never assumed any other alias on USENET other than the one that
I a currently using in the 20 years I have been using the Internet.

Correction:

Several years ago due to problems with email, I used a different
alias. But beyond that, my aliases has always been the same.

In any case, I have never assumed any alias other than the one that I
am currently using in this group, because I've only recently begun to
post in this group.

-Le Chaud Lapin-