The Impossibility of Flying Heavy Aircraft Without Training

"Gig 601XL Builder" wrDOTgiaconaATcox.net wrote in news:11vrmij7iu3hkf9
@news.supernews.com:

Stop replying to this idiot.





I try not to, but the Gig 601XL Builder keeps posting over and over. What a
brainwashed lowlife he is ha ha ha

The Bernoulli equation only applies to *incompressible* flow.

Right. But the Bernoulli principle applies to compressible and
incompressible flow. It is the source of the venturi effect, which
occurs in air, among other places.

What about reflexed airfoils?

I am not familiar with them. The trailing edge is depicted as pointing
up; does it do so when the wing is at a lifting angle of attack? Is
there an airflow separation near the trailing edge? If air is not being
deflected downwards somewhere, we're back to the lifting fairies.

Jose
--
Money: what you need when you run out of brains.
for Email, make the obvious change in the address.

But the Bernoulli principle applies to compressible and
incompressible flow.

True. But your original text suggested that the fluid *had* to be
compressible.

The trailing edge is depicted as pointing up; does it do so when the
wing is at a lifting angle of attack?

Good question. I don't know. Anyway, remember that there is no
overall downward movement of the air unless there exist wingtip
vortices. This suggests that the important downward momentum of air
happens *after* the air leaves the trailing edge. I'm not certain
that what direction the trailing edge is actually pointing is
critical. I'm skeptical that if you have an airfoil generating
positive lift, just tilting the trailing edge upwards slightly is
going to kill that lift.

Also, although theory (Kutta Condition) says that the air flow leaves
the trailing edge smoothly, my understanding is that in real life, the
rear stagnation point will be somewhat on the top surface of the
airfoil anyway.

On 2/22/2006 1:09 PM, Jim Macklin wrote:
Schumer would have been a trustee guard in a Nazi camp.


Speaking of camps, Americans shall be herded into their very own camps in the
not so far future. Provided by your very own FEMA.

By the way, any Americans still remember when FEMA suddenly appeared out of thin
air, in 1992, after the Hurricane Andrew disaster hit Florida? Many, many,
unanswered questions by the media _that_ day. LOL!

For what it's worth, the present FEMA has secretly existed since 1979, but the
original FEMA existed long before Carter.

http://www.sonic.net/sentinel/gvcon6.html


--
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Tyranny over these States. To prove this, let facts be submitted to a candid world."
- Declaration of Independence

The Pentagon Strike
http://www.pentagonstrike.co.uk/flash.htm

The Demolition of Building 7
http://911research.com/wtc/evidence/videos/index.html#building7

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- US President speaking about the U.S. Constitution,
http://www.counterpunch.org/leupp12142005.html

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Object evinces a design to reduce them under absolute Despotism, it is their
right, it is their duty, to throw off such Government, and to provide new Guards
for their future security."
- Declaration of Independence

But your original text suggested that the fluid *had* to be
compressible.

Yes, it did suggest that. It shouldn't have. My clumsiness.

Anyway, remember that there is no
overall downward movement of the air unless there exist wingtip
vortices.

An infinitely wide wing has no wingtips. You suggest it could not
provide lift. I've read the "wingtip vortices provide lift" papers, I'm
not convinced that the correlation implies a causation in that
direction. I see it as: the wing causes downwash which provides lift
(action-reaction) and =that= creates vortices. The higher pressure air
underneath the wing has to go somewhere - around (the wingtip) and up
makes sense to me, and that is a vortex.

What happens in the two-dimensional case?

I'm skeptical that if you have an airfoil generating
positive lift, just tilting the trailing edge upwards slightly is
going to kill that lift.

I agree with you. The downward movement of air is being generated over
the entire wing chord, and has some depth to it too. I suspect (without
solving any equations) that tilting the trailing edge upwards slightly
(that's what ailerons do, sort of) does reduce lift, but as the airflow
right underneath the airfoil gets deflected upwards, the air further
away (below) does not, leaving a small lower pressure region just below
the upward pointing trailing edge. The rest of the mass of air below
this small low pressure region continues downwards through its momentum.

Jose
--
Money: what you need when you run out of brains.
for Email, make the obvious change in the address.

Tim Ward wrote:

All those theories have been discredited anyway. It's invisible magic lift
fairies that do all the real work.

Tim Ward


Mary Schaefer's (NASA) "Lift Demons" and "Drag Demons"

...

The Role of Lift Demons and Thrust Pixies in Heavier Than Air Flight
Publication Date: April 2005

Abstract: The role of Lift Demons in aeronautics was first explained in 1994
by Mary Shafer (NASA). Since then, Shafer's work has been explored and
revised. This paper summarises advances in Lift Demon technology over the
last decade.

Keywords: Lift Demons, Thrust Pixies, lemon fondant

Question: How did the secret information on Lift Demons make it into the
public domain? I've been a practising Aircraft Performance Engineer for the
past 26 years and have always tried to explain how aeroplanes fly by using
the official public explanations regarding Bernoulli, airfoils and other
such rot. Civilians just weren't ready for the truth.
In fact, we generally don't speak about the magic directly. Most of our plans
and estimates usually end with the phrase "and then a miracle
happens".

Answer: The science of Lift Demons was declassified in 1994, throwing this
topic wide open for discussion and research.

According to Shafer "Lift is caused by Lift Demons.
These little, invisible demons hold on to the leading and trailing edges of
the aircraft and lift it into the air by flapping their wings (so, in a
reductionist sense, lift is actually caused by feathers). Some of the demons
are a little confused and they hold on backwards, causing drag. The reason
that planes stall at high alpha is that the leading edge demons get scared and
let go when they can't see the ground anymore.

Lift demons have good taste and don't like to look at ugly aircraft, so they
hold on backwards on ugly planes. That's why gliders have so much lift and so
little drag and why F-4s have lots of drag." This, however, did not address
what gives lift to the Lift Demons' wings. Again, according to Shafer
"Feathers. The multiple filaments on feathers trap the air molecules and they
struggle to escape, which causes the action-reaction that we call lift. Bat
wings don't have feathers but they're hairy and that works just about as well
(air molecules are a little claustrophobic)."

It was originally believed that Lift Demons got their lift from smaller Lift
Demons whose lift was, in turn, produced by even smaller Lift Demons leading
to the "Infinite Demons Theory" as proposed by the great Greek
philosopher-scientist Miasma. However, with the revival of scientific
knowledge that eventually ended the Dark Ages, it was realised that this
situation unresolvable according to Zeno's paradox. The "Infinite Demons
Theory" works in many problems of engineering significance, however, real
understanding requires that the ether be introduced into the analysis at
some point. The "Ether Concept" explains why planes fly more efficiently at
higher altitudes. This is an absolute necessity when studying orbital and
interplanetary travel where, it is believed, many of the Lift Demons are
unable to breathe.

As always the Chinese seem to have been there first. "The Genius of China",
tells of one Ko Hung. "Someone asked the Master (Ko Hung) about the
principles of mounting to dangerous heights and travelling into the vast
inane. The Master said "[...] some have made flying cars with wood from the
inner part of the jujube tree, using ox leather straps fastened to returning
blades so as to set the machine in motion. Others have the idea of making
five snakes, six dragons and three oxen to meet the 'hard wind' and ride on
it, not stopping until they have risen to a height of 40 li (about 65,000
feet). The the ch'i [emanation of the sky or perhaps wind] is extremely
hard, so much so that it can overcome the strength of human beings. [...]
Take dragons, for example; when they first rise they go up using the clouds
as steps, and after they attained a height of forty li then they rush
forward effortlessly gliding." The jujube tree device sounds like the
Osprey. Scholars believe that the term "dragon" referred to the Lift Demon
and that the Chinese had harnessed their power before the Western world had
even discovered the Lift Demons' existence.

Lift Demons operate differently on different aircraft types. They get dizzy
holding onto a spinning prop and become disorientated, thus more of them
face the wrong direction which increases the drag. Lift Demons have to be
magically bound to jet engines and an Airbus propulsion engineer explained
"It takes an average of three day's solid chanting and ritual to get one of
those 'engine' things to work. If us witches stopped our hard work, there'd
be planes dropping out of the sky all over the place. We should never have
let you lot find out about being able to fly, it's been nothing but trouble
ever since."

Recognition of Lift Demons has also solved one of aviation's oldest puzzles:
Gremlins. There appears to be a connection between Gremlins and Lift Demons.
Gremlins may be Lift Demons that have, in some way, turned against the
pilot. Instead of assisting him in his task of keeping the machine in the
air, they do the opposite. The reason may be that, after reading about the
Bernoulli/Newton dichotomy, they have become confused.

Much has been written about Gremlins, dating back to WWII. Gremlins have been
known to run towards the nose of an aircraft, causing it to dive into the
sea, showing that they have at least some knowledge of the principles of
flight. These days, most planes carry a full complement of In-Flight Gremlins;
although they must be carefully managed, their presence generally inhibits
the transformation of rogue Lift Demons into Gremlins.

Further study of Lift Demons was carried out by an aero-industry weights
engineer who submitted the following scientific paper in 2004 to celebrate
the anniversary of Shafer's ground-breaking article:

"There are still people in this company who think we weigh aircraft to find
out how much they weigh, not to calculate stresses. Of course we need to
know how much the thing weighs. How are we ever going to know how many
Thrust Pixies we need to get the thing off the ground if we don't know the
weight? Or should that be "Lift Demons"? Pixies have largely fallen into
disrepute - something about Bernoulli not being representative in unbounded
conditions and cause and effect being transposed in the Newtonian model.

In fact the use of Lift Demons on civil aircraft programmes is generally not
that good an idea. The Demon binding contract tends to specify payment in
blood or souls. This is readily achievable with aircraft of military
function, but frowned upon in civilian circles as they may attempt to
acquire payment outside of the terms of their binding contract. Lift Demons
are not used on Elf bombers. We don't talk about Lift [Thrust] Pixies too
often as it seems to upset the self-loading cargo [passengers]. Pixies
require payment in cakes, flowers or nice thoughts.

These are readily sourced either from the in-flight catering, or provided
cost-free by the passengers. Clearly this would not work well within an
operational military environment. Air force cooking is not renowned for the
"light and fluffy texture" that Thrust Pixies demand, the availability of
flowers might be problematic in desert operations, and nice thoughts may
also be hard to find during times of active operations.

There is also a scalability issue. While one rampant Lift Demon would have
few problems supporting a fighter aircraft (particularly if there is an
immediate prospect of blood), it'll struggle to achieve level controlled
flight of a 560 tonne Airbus A380. Use of more than one Lift Demon on the
same flight vehicle is contra-indicated (they squabble and eat each other).
Communities of Thrust Pixies can be encouraged to work together on the same
aircraft by the provision of advanced technologies such as Lemon fondant
icing, variegated tulips or in-flight romantic comedies. Ryanair once
requested Leprachauns be installed in place of Lift [Thrust] Pixies, but
Leprechauns have a mission statement which indicates their desire for
monetary gain, and their willingness to search all over the world for it.

This makes Lift Leprechauns expensive to keep (gold vs. lemon fondant
icing), and makes it difficult to establish a regular route network as the
Lift Leprechauns don't like to continuously visit the same locations. By
law, aircraft also have to have a full complement of In-Flight Gremlins, but
these are generally not a problem unless you feed the Wingtip Vortex Faeries
after midnight."

His article shows that we've moved on a great deal since 1994. It has been
known for some time that Lift Demons are best suited to military uses. In
spite of suggestions that Pixies have fallen into disrepute, outside of
military aviation it is Lift Demons that are considered passé - they have
notoriously short attention spans and the ones used on Harriers have
problems discriminating between air and water.

Inbreeding in pursuit of the ultimate high performance Lift Demon may have
been the cause. In civil aviation, the way ahead still lies with Thrust
Pixies, large amounts of lemon fondant icing and in-flight Hugh Grant movies.
Many instances of civil planes mysteriously falling out of the sky can be
traced to (a) cessation of happy thoughts/lack of lemon fondant for the pixies
(resulting in "Pixie Fatigue" or even "catastrophic pixie failure") or to
(b) a large amount of happy thoughts/gateau mountain at ground level
distracting the pixies from their task. Thrust Pixies dislike
Marmite/Vegemite (yeast extract) and since such spreads can cause unhappy
thoughts in some passengers, airline caterers are careful to avoid these.

A note on Catastrophic Pixie Failu Temporary pixie problems resulting in
turbulence or sudden loss of altitude causes unhappy thoughts in the
passengers (which is why cabin staff and pilots alway play down such
occurrences). The resulting loss of happy thoughts causes further Pixie
failure, worsening the situation.

This makes passengers have even more unhappy thoughts and the Pixies become
more fatigued; some may even leave the aircraft. Unless counter-acted by large
lemon fondant reserves, Pixie Failure reaches catastrophic proportions and the
aircraft is doomed.

Modern aircraft designers use Lift Fairies and avoid the whole controversy
regarding the used of Lift Demons on civil aircraft programmes. Coming from
a less benevolent cast, Lift Fairies are less dependent on nice thoughts or
cakes. Fairies tend to less concerned with good and evil and hence make
better dual use aircraft. Another major headache today is how to get 707
Lift Fairies at a reasonable price. Many of the older aircraft-specific
fairies have become rare, if not unavailable. Aircraft numbering relates to
the type and quantity of Lift Demons or Lift Fairies needed. For example a
C-130 requires 130 "C class" Lift Demons while an Airbus A380 uses 380 "A"
class Thrust Pixies. Aero engineers have a scale of values (proprietary
information, not available in the public domain) allowing them to substitute
different numbers of Pixies and Demons with different lifting abilities,
thus making best use of the available surfaces.

There was short-lived interest in breeding a generic, or at least dual-use,
"Thrust Demon" but the blood-loving Lift Demons ate the gateau-loving Thrust
Pixies. In vitro techniques failed because their genietic [sic] material is
incompatible so there are no hybrid Thrust Demons. DNA sequencing has
allowed us to distinguish between many castes of Lift Demon, Thrust Fairy
etc. For example due credit should be given to the inelegantly named Fart
Fairies without whose bean eating and gas production, no machine could power
itself from the earth's surface. The shy Turbine Winder-Rounder Gnomes hide
inside those so-called engine nacelles from the public and indulge their
serious kerosene drinking problems. Why else would the engines be called
Gnome engines? Leading-Edge Leeries give the extra little push that keeps
the nose up. The unfortunate tendency for RAF Harriers to crash into the sea
has led to speculation that Harriers are equipped with Sirens or that the
crashes resulted from an ill-advised experiment in using Water Nymphs (these
are better suited to submarine propulsion). In any case, only export
versions of the Harrier are likely to use Sirens, while those for the
British domestic market use Banshees leased from the Irish.

Thrust Pixies are adequate for civil aircraft, while Lift Demons were good
in military applications in years past, but modern Naval Aviation is
currently all Angel-powered. The very best ones are, of course, Blue Angels.
This is why they report their altitude as "angels twenty" or such. In
addition, many Navy pilots claim that black air has no lift, which means
they can get all night in to supplement their daytime naps between meals.
This shows that Angels and Naval Lift Demons are strictly diurnal.
Genetically engineered, military-tolerant Thrust Pixies may be what is
needed. Thrust Demons might also have applications in getting Air Force
maritime patrol aircraft to stop reaching "prudent limit of endurance" by 2
p.m. (local time) every Friday just after reporting a "possible intruder"
submarine in the exercise area, and not be restored to flying status until 9
a.m. Monday, thus leaving the ships to stay out over the weekend looking for
the "intruder".

There are no Anti-Gravity Demons so a different approach has to be taken in
this field of research. Current research into inertia-free propulsion has
shown great promise through the use of properly modified felines. Butter is
spread evenly over the felines back. When the creature is tossed lightly
into the air, the third law of universal fate dictates that it must land
butter side down. However this does not occur due to the intervention of the
feline landing axiom (feet first). The above conflicting forces result in a
stable hover. The subject felines have demonstrated the ability to control
their own velocity at will. The only loose ends delaying the full
commercialisation of this process is the matter of persuading the felines to
(a) work in teams; (b) not lick off the butter and (c) follow a flight plan.

As there seems to be a deficiency in feline herding instincts, any
suggestions would be appreciated by the researchers involved.

An infinitely wide wing has no wingtips. You suggest it could not
provide lift.

Heck no. It just does so with no *net* downward momentum of air. In
other words, the upward momentum ahead of the wing is equal to the
downward momentum at the rear of the wing.

I've read the "wingtip vortices provide lift" papers,

I'm not proposing that.

the wing causes downwash which provides lift (action-reaction) and
=that= creates vortices.

Infinite wings have no downwash, yet provide lift. By *definition*,
downwash is caused by wingtip vortices.

The higher pressure air underneath the wing has to go somewhere -
around (the wingtip) and up makes sense to me, and that is a vortex.

Except when you don't have wingtips. ;-)

local to RAH (only):

The question on my mind this morning was, Did we run him off,
or Did his ISP mercifully slit his neck.

But he's still at it in some of the other groups.
Rec.aviation.Military is unfortunately still trying to argue the
guy to his senses(?).

Very well done, folks.

Richard

Heck no. It just does so with no *net* downward momentum of air. In
other words, the upward momentum ahead of the wing is equal to the
downward momentum at the rear of the wing.

What upward momentum? The air starts out still, and infinitely wide
wing comes flying through it, when all is done air has to have been
deflected downwards, at the very least to satisfy Newton.

Behind the wing, air is moving downwards, there is higher pressure below
the wing's path, and lower pressure above the wing's path. The air will
recover, as the pressure equalizes (eventually pushing down on the
earth's surface and up into the lower pressure region)

Infinite wings have no downwash, yet provide lift. By *definition*,
downwash is caused by wingtip vortices.

Well, then an infinite wing ought to have something that is not called
downwash, but keeps Newton happy. Call it downflow, call it pressure
bounce.. but it's something.

Jose
--
Money: what you need when you run out of brains.
for Email, make the obvious change in the address.

What upward momentum? The air starts out still, and infinitely wide
wing comes flying through it,

As the wing approaches, the air starts moving up, eagerly anticipating
the meeting. Called "upwash".

Well, then an infinite wing ought to have something that is not
called
downwash, but keeps Newton happy. Call it downflow, call it pressure
bounce.. but it's something.

Newton is happy. The high pressure air on the bottom of the airfoil
pushes on the airfoil, the airfoil pushes back

Anyway, I'm just the messenger. The idea that there is no net downward
momentum of infinite airfoils is stated in a number of aerodynamics
books.