The Impossibility of Flying Heavy Aircraft Without Training

[snip]

I think we are pretty much in full agreement, and were merely using
different words, or stressing concepts that don't matter for the image
being discussed by the other.

When an infinite (or 2D) wing starts its takeoff roll, is there not a
vortex generated? Is not some air thrown down at the outset? (Granted
the vortex isn't at the wingtips and has a different axis, but air goes
down behind the wing and up ahead of it, which wasn't the case before
the takeoff roll).

Steady state, the wing keeps throwing air down but it keeps coming back
up (in front of it). I suppose I am using the term "throwing air down"
a bit more sloppily than you are taking it - I do mean it to be the same
as "imparting a downward acceleration". However, in all the pictures
I've seen, air does leave the wing with a downward velocity with a wing
in level flight. I just find the image to be more useful to me than the
"high pressure low pressure" because it better explains where the
pressure comes from.

It still sounds like you are just saying that since some air
is somehow held down so it can later "come back up" you are
simply saying that there is some density increase for higher
pressure air. While true to a tiny extent, this is
irrelevant to the whole issue.

I'm saying it just to answer the (valid) question of "where the air
goes". Just enough of it gets scrunched up to hold the airplane up.
PV=nRT. In this case the V is big (and not really well defined), and
nRT is effectively constant.

Even if the gravity does not
affect the fluid, an underwater wing moved through the water
at an AOA will apply a force to the fluid and cause it to
move down. The longer you do this, the longer that force
will accelerate the ball of fluid down.

Exactly. And this is the reason I hold to "the wing throws the air
down, the earth gets in the way".

You don't need any compression to have pressure. Pressure
is sufficient for lift. A perfectly incompressible fluid
still has pressure.

Pressure is sufficient for lift. but a perfectly incompressible fluid
is an ideal that does not exist. The electrons get squished a little
harder; that supplies the force. Granted this is not important in the
calculation of what pressure does, and the distances involved are less
than miniscule, but it is important conceptually in seeing "just how
things work" on a basic level. "It goes =somewhere=."

I think we are basically in agreement with the physics, just disagree as
to what parts of the physics are important, because we are evaluating
importance differently.

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

On Wed, 8 Mar 2006 at 23:12:19 in message
, Jose
wrote:

The original question is ok (after all, in physics we use cylindrical
cows, frictionless surfaces, and point masses). But the comment at the
end is very misleading. The momentum is never "destroyed". It is
actually transferred to the wall, and thus to the earth. What they are
probably trying to say is that there is usually some rebound of the
water, and it sprays all over the place rather than becoming embedded
like machine gun bullets in sand... which would have been a better example.

I have got to be quick here - busy the next couple of days!

Their statement may be a bit sloppy but the fact is that because the
wall is very rigid and firmly fixed the ground an accurate calculation
of the force can be made by assuming the momentum is destroyed. The
effect on the earth is so small that it is minuscule compared to the
practical result.

Any changes to the entire earth as a result are insignificant.

Depends whether you are trying to understand the fundamental physics or
just trying to calculate an answer.

I thought the basic principles have been stated and stated! It is
whether or not we have a clear understanding of lift or not that seems
to be going around in circles. What happens to the earth a long way away
from the aircraft is, for all practical purposes insignificant and not
worth worrying about. It certainly does not prove that down wash has
nothing to do with lift for example as has been stated.
--
David CL Francis

On Thu, 9 Mar 2006 at 16:56:45 in message
, Jose
wrote:

Pressure is sufficient for lift. but a perfectly incompressible fluid
is an ideal that does not exist. The electrons get squished a little
harder; that supplies the force. Granted this is not important in the
calculation of what pressure does, and the distances involved are less
than miniscule, but it is important conceptually in seeing "just how
things work" on a basic level. "It goes =somewhere=."

No metal that is incompressible exists either. The point is lost about
the fundamentals of Bernoulli' theorem. Compressibility is not a part of
the simple theory and it applies just as much to water in pipes.

If water flows through a pipe and comes to a place where the pipe
narrows smoothly then the water speeds up as the mass flow through a
pipe is constant along its length. The pressure then drops as some of
the pressure energy is transformed into kinetic energy. Many measurement
devices depend on this as do carburettors. The keels and rudders of
boats generate lift in just the same way as wings.
--
David CL Francis

It was a challenge back in the early 1980's being thrust from a Cessna
402 and taking off, climbing, holding, and approaching in a 747 and
walking away from the landing however that's how we did it back then
it really flies like a big 172, you just need to be patient in the
turns, it takes time for the ailerons and roll spoilers to react
(ailerons, youv'e seen pictures) otherwise you get some flutter.

Bush


On Wed, 22 Feb 2006 06:15:59 -0600, Immanuel Goldstein
wrote:

The Impossibility of Flying Heavy Aircraft Without Training

Nila Sagadevan | February 21 2006

Nila Sagadevan is an aeronautical engineer and a qualified pilot of heavy aircraft.

[...]

What follows is an attempt to bury this myth once and for all, because I’ve
heard this ludicrous explanation bandied about, ad nauseum, on the Internet and
the TV networks—invariably by people who know nothing substantive about flight
simulators, flying, or even airplanes.

A common misconception non-pilots have about simulators is how “easy” it is to
operate them. They are indeed relatively easy to operate if the objective is to
make a few lazy turns and frolic about in the “open sky”. But if the intent is
to execute any kind of a maneuver with even the least bit of precision, the task
immediately becomes quite daunting. And if the aim is to navigate to a specific
geographic location hundreds of miles away while flying at over 500 MPH, 30,000
feet above the ground the challenges become virtually impossible for an
untrained pilot.

And this, precisely, is what the four hijacker pilots who could not fly a Cessna
around an airport are alleged to have accomplished in multi-ton, high-speed
commercial jets on 9/11.

For a person not conversant with the practical complexities of pilotage, a
modern flight simulator could present a terribly confusing and disorienting
experience. These complex training devices are not even remotely similar to the
video games one sees in amusement arcades, or even the software versions
available for home computers.

In order to operate a modern flight simulator with any level of skill, one has
to not only be a decent pilot to begin with, but also a skilled instrument-rated
one to boot — and be thoroughly familiar with the actual aircraft type the
simulator represents, since the cockpit layouts vary between aircraft.

The only flight domains where an arcade/PC-type game would even begin to
approach the degree of visual realism of a modern professional flight simulator
would be during the take-off and landing phases. During these phases, of course,
one clearly sees the bright runway lights stretched out ahead, and even
peripherally sees images of buildings, etc. moving past. Take-offs—even
landings, to a certain degree—are relatively “easy”, because the pilot has
visual reference cues that exist “outside” the cockpit.

But once you’ve rotated, climbed out, and reached cruising altitude in a
simulator (or real airplane), and find yourself en route to some distant
destination (using sophisticated electronic navigation techniques), the
situation changes drastically: the pilot loses virtually all external visual
reference cues. S/he is left entirely at the mercy of an array of complex flight
and navigation instruments to provide situational cues (altitude, heading,
speed, attitude, etc.)

In the case of a Boeing 757 or 767, the pilot would be faced with an EFIS
(Electronic Flight Instrumentation System) panel comprised of six large
multi-mode LCDs interspersed with clusters of assorted “hard” instruments. These
displays process the raw aircraft system and flight data into an integrated
picture of the aircraft situation, position and progress, not only in horizontal
and vertical dimensions, but also with regard to time and speed as well. When
flying “blind”, I.e., with no ground reference cues, it takes a highly skilled
pilot to interpret, and then apply, this data intelligently. If one cannot
translate this information quickly, precisely and accurately (and it takes an
instrument-rated pilot to do so), one would have ZERO SITUATIONAL AWARENESS.
I.e., the pilot wouldn’t have a clue where s/he was in relation to the earth.
Flight under such conditions is referred to as “IFR”, or Instrument Flight Rules.

And IFR Rule #1: Never take your eyes off your instruments, because that’s all
you have!

The corollary to Rule #1: If you can’t read the instruments in a quick, smooth,
disciplined, scan, you’re as good as dead. Accident records from around the
world are replete with reports of any number of good pilots — I.e., professional
instrument-rated pilots — who ‘bought the farm’ because they screwed up while
flying in IFR conditions.

Let me place this in the context of the 9/11 hijacker-pilots. These men were
repeatedly deemed incompetent to solo a simple Cessna-172 — an elementary
exercise that involves flying this little trainer once around the patch on a
sunny day. A student’s first solo flight involves a simple circuit: take-off,
followed by four gentle left turns ending with a landing back on the runway.
This is as basic as flying can possibly get.

Not one of the hijackers was deemed fit to perform this most elementary exercise
by himself.

In fact, here’s what their flight instructors had to say about the aptitude of
these budding aviators:

Mohammed Atta: "His attention span was zero."

Khalid Al-Mihdhar: "We didn't kick him out, but he didn't live up to our standards."

Marwan Al-Shehhi: “He was dropped because of his limited English and
incompetence at the controls.”

Salem Al-Hazmi: "We advised him to quit after two lessons.”

Hani Hanjour: "His English was horrible, and his mechanical skills were even
worse. It was like he had hardly even ever driven a car. I’m still to this day
amazed that he could have flown into the Pentagon. He could not fly at all.”

Now let’s take a look at American Airlines Flight 77. Passenger/hijacker Hani
Hanjour rises from his seat midway through the flight, viciously fights his way
into the cockpit with his cohorts, overpowers Captain Charles F. Burlingame and
First Officer David Charlebois, and somehow manages to toss them out of the
cockpit (for starters, very difficult to achieve in a cramped environment
without inadvertently impacting the yoke and thereby disengaging the autopilot).
One would correctly presume that this would present considerable difficulties to
a little guy with a box cutter—Burlingame was a tough, burly, ex-Vietnam F4
fighter jock who had flown over 100 combat missions. Every pilot who knows him
says that rather than politely hand over the controls, Burlingame would have
instantly rolled the plane on its back so that Hanjour would have broken his
neck when he hit the floor. But let’s ignore this almost natural reaction
expected of a fighter pilot and proceed with this charade.

Nonetheless, imagine that Hanjour overpowers the flight deck crew, removes them
from the cockpit and takes his position in the captain’s seat. Although weather
reports state this was not the case, let’s say Hanjour was lucky enough to
experience a perfect CAVU day (Ceiling And Visibility Unlimited). If Hanjour
looked straight ahead through the windshield, or off to his left at the ground,
at best he would see, 35,000 feet -- 7 miles -- below him, a murky
brownish-grey-green landscape, virtually devoid of surface detail, while the
aircraft he was now piloting was moving along, almost imperceptibly and in eerie
silence, at around 500 MPH (about 750 feet every second).

In a real-world scenario (and given the reported weather conditions that day),
he would likely have seen clouds below him completely obscuring the ground he
was traversing. With this kind of “situational non-awareness”, Hanjour might as
well have been flying over Argentina, Russia, or Japan—he wouldn’t have had a
clue as to where, precisely, he was.

After a few seconds (at 750 ft/sec), Hanjour would figure out there’s little
point in looking outside—there’s nothing there to give him any real visual cues.
For a man who had previously wrestled with little Cessnas, following freeways
and railroad tracks (and always in the comforting presence of an instructor),
this would have been a strange, eerily unsettling environment indeed.

Seeing nothing outside, Mr. Hanjour would be forced to divert his attention to
his instrument panel, where he’d be faced with a bewildering array of
instruments. He would then have to very quickly interpret his heading, ground
track, altitude, and airspeed information on the displays before he could even
figure out where in the world he was, much less where the Pentagon was located
in relation to his position!

After all, before he can crash into a target, he has to first find the target.

It is very difficult to explain this scenario, of an utter lack of ground
reference, to non-pilots; but let it suffice to say that for these incompetent
hijacker non-pilots to even consider grappling with such a daunting task would
have been utterly overwhelming. They wouldn’t have known where to begin.

But, for the sake of discussion let’s stretch things beyond all plausibility and
say that Hanjour—whose flight instructor claimed “couldn’t fly at all”—somehow
managed to figure out their exact position on the American landscape in relation
to their intended target as they traversed the earth at a speed five times
faster than they had ever flown by themselves before.

Once he had determined exactly where he was, he would need to figure out where
the Pentagon was located in relation to his rapidly-changing position. He would
then need to plot a course to his target (one he cannot see with his
eyes—remember, our ace is flying solely on instruments).

In order to perform this bit of electronic navigation, he would have to be very
familiar with IFR procedures. None of these chaps even knew what a navigational
chart looked like, much less how to how to plug information into flight
management computers (FMC) and engage LNAV (lateral navigation automated mode).
If one is to believe the official story, all of this was supposedly accomplished
by raw student pilots while flying blind at 500 MPH over unfamiliar (and
practically invisible) terrain, using complex methodologies and employing
sophisticated instruments.

To get around this little problem, the official storyline suggests these men
manually flew their aircraft to their respective targets (NB: This still
wouldn’t relieve them of the burden of navigation). But let’s assume Hanjour
disengaged the autopilot and auto-throttle and hand-flew the aircraft to its
intended—and invisible—target on instruments alone until such time as he could
get a visual fix. This would have necessitated him to fly back across West
Virginia and Virginia to Washington DC. (This portion of Flight 77’s flight path
cannot be corroborated by any radar evidence that exists, because the aircraft
is said to have suddenly disappeared from radar screens over Ohio, but let’s not
mull over that little point.)

According to FAA radar controllers, “Flight 77” then suddenly pops up over
Washington DC and executes an incredibly precise diving turn at a rate of 360
degrees/minute while descending at 3,500 ft/min, at the end of which “Hanjour”
allegedly levels out at ground level. Oh, I almost forgot: He also had the
presence of mind to turn off the transponder in the middle of this incredibly
difficult maneuver (one of his instructors later commented the hapless fellow
couldn’t have spelt the word if his life depended on it).

The maneuver was in fact so precisely executed that the air traffic controllers
at Dulles refused to believe the blip on their screen was a commercial airliner.
Danielle O’Brian, one of the air traffic controllers at Dulles who reported
seeing the aircraft at 9:25 said, “The speed, the maneuverability, the way that
he turned, we all thought in the radar room, all of us experienced air traffic
controllers, that that was a military plane.”

And then, all of a sudden we have magic. Voila! Hanjour finds the Pentagon
sitting squarely in his sights right before him.

But even that wasn’t good enough for this fanatic Muslim kamikaze pilot. You
see, he found that his “missile” was heading towards one of the most densely
populated wings of the Pentagon—and one occupied by top military brass,
including the Secretary of Defense, Rumsfeld. Presumably in order to save these
men’s lives, he then executes a sweeping 270-degree turn and approaches the
building from the opposite direction and aligns himself with the only wing of
the Pentagon that was virtually uninhabited due to extensive renovations that
were underway (there were some 120 civilians construction workers in that wing
who were killed; their work included blast-proofing the outside wall of that wing).

I shan’t get into the aerodynamic impossibility of flying a large commercial
jetliner 20 feet above the ground at over 400 MPH. A discussion on ground effect
energy, tip vortex compression, downwash sheet reaction, wake turbulence, and
jetblast effects are beyond the scope of this article (the 100,000-lb jetblast
alone would have blown whole semi-trucks off the roads.)

Let it suffice to say that it is physically impossible to fly a 200,000-lb
airliner 20 feet above the ground at 400 MPH.

The author, a pilot and aeronautical engineer, challenges any pilot in the world
to do so in any large high-speed aircraft that has a relatively low wing-loading
(such as a commercial jet). I.e., to fly the craft at 400 MPH, 20 feet above
ground in a flat trajectory over a distance of one mile.

Why the stipulation of 20 feet and a mile? There were several street light poles
located up to a mile away from the Pentagon that were snapped-off by the
incoming aircraft; this suggests a low, flat trajectory during the final
pre-impact approach phase. Further, it is known that the craft impacted the
Pentagon’s ground floor. For purposes of reference: If a 757 were placed on the
ground on its engine nacelles (I.e., gear retracted as in flight profile), its
nose would be almost 20 above the ground! Ergo, for the aircraft to impact the
ground floor of the Pentagon, Hanjour would have needed to have flown in with
the engines buried 10-feet deep in the Pentagon lawn. Some pilot.

At any rate, why is such ultra-low-level flight aerodynamically impossible?
Because the reactive force of the hugely powerful downwash sheet, coupled with
the compressibility effects of the tip vortices, simply will not allow the
aircraft to get any lower to the ground than approximately one half the distance
of its wingspan—until speed is drastically reduced, which, of course, is what
happens during normal landings.

In other words, if this were a Boeing 757 as reported, the plane could not have
been flown below about 60 feet above ground at 400 MPH. (Such a maneuver is
entirely within the performance envelope of aircraft with high wing-loadings,
such as ground-attack fighters, the B1-B bomber, and Cruise missiles—and the
Global Hawk.)

The very same navigational challenges mentioned above would have faced the
pilots who flew the two 767s into the Twin Towers, in that they, too, would have
had to have first found their targets. Again, these chaps, too, miraculously
found themselves spot on course. And again, their “final approach” maneuvers at
over 500 MPH are simply far too incredible to have been executed by pilots who
could not solo basic training aircraft.

Conclusion
The writers of the official storyline expect us to believe, that once the flight
deck crews had been overpowered, and the hijackers “took control” of the various
aircraft, their intended targets suddenly popped up in their windshields as they
would have in some arcade game, and all that these fellows would have had to do
was simply aim their airplanes at the buildings and fly into them. Most people
who have been exposed only to the official storyline have never been on the
flight deck of an airliner at altitude and looked at the outside world; if they
had, they’d realize the absurdity of this kind of reasoning.

In reality, a clueless non-pilot would encounter almost insurmountable
difficulties in attempting to navigate and fly a 200,000-lb airliner into a
building located on the ground, 7 miles below and hundreds of miles away and out
of sight, and in an unknown direction, while flying at over 500 MPH — and all
this under extremely stressful circumstances.

Complete text:
http://physics911.net/sagadevan.htm

Hmmm one has to wonder just where he is going with this story?!
So either the hijackers were better pilots than this story would imply or,
they had help from someone else!
anyway that is the way "I" look at it. We may never know the "true" story of
9/11/01




On Wed, 22 Feb 2006 06:15:59 -0600, Immanuel Goldstein
wrote:

The Impossibility of Flying Heavy Aircraft Without Training

Nila Sagadevan | February 21 2006

Nila Sagadevan is an aeronautical engineer and a qualified pilot of heavy
aircraft.

[...]

What follows is an attempt to bury this myth once and for all, because
I've
heard this ludicrous explanation bandied about, ad nauseum, on the
Internet and
the TV networks-invariably by people who know nothing substantive about
flight
simulators, flying, or even airplanes.

A common misconception non-pilots have about simulators is how "easy" it
is to
operate them. They are indeed relatively easy to operate if the objective
is to
make a few lazy turns and frolic about in the "open sky". But if the
intent is
to execute any kind of a maneuver with even the least bit of precision,
the task
immediately becomes quite daunting. And if the aim is to navigate to a
specific
geographic location hundreds of miles away while flying at over 500 MPH,
30,000
feet above the ground the challenges become virtually impossible for an
untrained pilot.

And this, precisely, is what the four hijacker pilots who could not fly a
Cessna
around an airport are alleged to have accomplished in multi-ton,
high-speed
commercial jets on 9/11.

For a person not conversant with the practical complexities of pilotage,
a
modern flight simulator could present a terribly confusing and
disorienting
experience. These complex training devices are not even remotely similar
to the
video games one sees in amusement arcades, or even the software versions
available for home computers.

In order to operate a modern flight simulator with any level of skill,
one has
to not only be a decent pilot to begin with, but also a skilled
instrument-rated
one to boot - and be thoroughly familiar with the actual aircraft type
the
simulator represents, since the cockpit layouts vary between aircraft.

The only flight domains where an arcade/PC-type game would even begin to
approach the degree of visual realism of a modern professional flight
simulator
would be during the take-off and landing phases. During these phases, of
course,
one clearly sees the bright runway lights stretched out ahead, and even
peripherally sees images of buildings, etc. moving past. Take-offs-even
landings, to a certain degree-are relatively "easy", because the pilot
has
visual reference cues that exist "outside" the cockpit.

But once you've rotated, climbed out, and reached cruising altitude in a
simulator (or real airplane), and find yourself en route to some distant
destination (using sophisticated electronic navigation techniques), the
situation changes drastically: the pilot loses virtually all external
visual
reference cues. S/he is left entirely at the mercy of an array of complex
flight
and navigation instruments to provide situational cues (altitude,
heading,
speed, attitude, etc.)

In the case of a Boeing 757 or 767, the pilot would be faced with an EFIS
(Electronic Flight Instrumentation System) panel comprised of six large
multi-mode LCDs interspersed with clusters of assorted "hard"
instruments. These
displays process the raw aircraft system and flight data into an
integrated
picture of the aircraft situation, position and progress, not only in
horizontal
and vertical dimensions, but also with regard to time and speed as well.
When
flying "blind", I.e., with no ground reference cues, it takes a highly
skilled
pilot to interpret, and then apply, this data intelligently. If one
cannot
translate this information quickly, precisely and accurately (and it
takes an
instrument-rated pilot to do so), one would have ZERO SITUATIONAL
AWARENESS.
I.e., the pilot wouldn't have a clue where s/he was in relation to the
earth.
Flight under such conditions is referred to as "IFR", or Instrument
Flight Rules.

And IFR Rule #1: Never take your eyes off your instruments, because
that's all
you have!

The corollary to Rule #1: If you can't read the instruments in a quick,
smooth,
disciplined, scan, you're as good as dead. Accident records from around
the
world are replete with reports of any number of good pilots - I.e.,
professional
instrument-rated pilots - who 'bought the farm' because they screwed up
while
flying in IFR conditions.

Let me place this in the context of the 9/11 hijacker-pilots. These men
were
repeatedly deemed incompetent to solo a simple Cessna-172 - an elementary
exercise that involves flying this little trainer once around the patch
on a
sunny day. A student's first solo flight involves a simple circuit:
take-off,
followed by four gentle left turns ending with a landing back on the
runway.
This is as basic as flying can possibly get.

Not one of the hijackers was deemed fit to perform this most elementary
exercise
by himself.

In fact, here's what their flight instructors had to say about the
aptitude of
these budding aviators:

Mohammed Atta: "His attention span was zero."

Khalid Al-Mihdhar: "We didn't kick him out, but he didn't live up to our
standards."

Marwan Al-Shehhi: "He was dropped because of his limited English and
incompetence at the controls."

Salem Al-Hazmi: "We advised him to quit after two lessons."

Hani Hanjour: "His English was horrible, and his mechanical skills were
even
worse. It was like he had hardly even ever driven a car. I'm still to
this day
amazed that he could have flown into the Pentagon. He could not fly at
all."

Now let's take a look at American Airlines Flight 77. Passenger/hijacker
Hani
Hanjour rises from his seat midway through the flight, viciously fights
his way
into the cockpit with his cohorts, overpowers Captain Charles F.
Burlingame and
First Officer David Charlebois, and somehow manages to toss them out of
the
cockpit (for starters, very difficult to achieve in a cramped environment
without inadvertently impacting the yoke and thereby disengaging the
autopilot).
One would correctly presume that this would present considerable
difficulties to
a little guy with a box cutter-Burlingame was a tough, burly, ex-Vietnam
F4
fighter jock who had flown over 100 combat missions. Every pilot who
knows him
says that rather than politely hand over the controls, Burlingame would
have
instantly rolled the plane on its back so that Hanjour would have broken
his
neck when he hit the floor. But let's ignore this almost natural reaction
expected of a fighter pilot and proceed with this charade.

Nonetheless, imagine that Hanjour overpowers the flight deck crew,
removes them
from the cockpit and takes his position in the captain's seat. Although
weather
reports state this was not the case, let's say Hanjour was lucky enough
to
experience a perfect CAVU day (Ceiling And Visibility Unlimited). If
Hanjour
looked straight ahead through the windshield, or off to his left at the
ground,
at best he would see, 35,000 feet -- 7 miles -- below him, a murky
brownish-grey-green landscape, virtually devoid of surface detail, while
the
aircraft he was now piloting was moving along, almost imperceptibly and
in eerie
silence, at around 500 MPH (about 750 feet every second).

In a real-world scenario (and given the reported weather conditions that
day),
he would likely have seen clouds below him completely obscuring the
ground he
was traversing. With this kind of "situational non-awareness", Hanjour
might as
well have been flying over Argentina, Russia, or Japan-he wouldn't have
had a
clue as to where, precisely, he was.

After a few seconds (at 750 ft/sec), Hanjour would figure out there's
little
point in looking outside-there's nothing there to give him any real
visual cues.
For a man who had previously wrestled with little Cessnas, following
freeways
and railroad tracks (and always in the comforting presence of an
instructor),
this would have been a strange, eerily unsettling environment indeed.

Seeing nothing outside, Mr. Hanjour would be forced to divert his
attention to
his instrument panel, where he'd be faced with a bewildering array of
instruments. He would then have to very quickly interpret his heading,
ground
track, altitude, and airspeed information on the displays before he could
even
figure out where in the world he was, much less where the Pentagon was
located
in relation to his position!

After all, before he can crash into a target, he has to first find the
target.

It is very difficult to explain this scenario, of an utter lack of ground
reference, to non-pilots; but let it suffice to say that for these
incompetent
hijacker non-pilots to even consider grappling with such a daunting task
would
have been utterly overwhelming. They wouldn't have known where to begin.

But, for the sake of discussion let's stretch things beyond all
plausibility and
say that Hanjour-whose flight instructor claimed "couldn't fly at
all"-somehow
managed to figure out their exact position on the American landscape in
relation
to their intended target as they traversed the earth at a speed five
times
faster than they had ever flown by themselves before.

Once he had determined exactly where he was, he would need to figure out
where
the Pentagon was located in relation to his rapidly-changing position. He
would
then need to plot a course to his target (one he cannot see with his
eyes-remember, our ace is flying solely on instruments).

In order to perform this bit of electronic navigation, he would have to
be very
familiar with IFR procedures. None of these chaps even knew what a
navigational
chart looked like, much less how to how to plug information into flight
management computers (FMC) and engage LNAV (lateral navigation automated
mode).
If one is to believe the official story, all of this was supposedly
accomplished
by raw student pilots while flying blind at 500 MPH over unfamiliar (and
practically invisible) terrain, using complex methodologies and employing
sophisticated instruments.

To get around this little problem, the official storyline suggests these
men
manually flew their aircraft to their respective targets (NB: This still
wouldn't relieve them of the burden of navigation). But let's assume
Hanjour
disengaged the autopilot and auto-throttle and hand-flew the aircraft to
its
intended-and invisible-target on instruments alone until such time as he
could
get a visual fix. This would have necessitated him to fly back across
West
Virginia and Virginia to Washington DC. (This portion of Flight 77's
flight path
cannot be corroborated by any radar evidence that exists, because the
aircraft
is said to have suddenly disappeared from radar screens over Ohio, but
let's not
mull over that little point.)

According to FAA radar controllers, "Flight 77" then suddenly pops up
over
Washington DC and executes an incredibly precise diving turn at a rate of
360
degrees/minute while descending at 3,500 ft/min, at the end of which
"Hanjour"
allegedly levels out at ground level. Oh, I almost forgot: He also had
the
presence of mind to turn off the transponder in the middle of this
incredibly
difficult maneuver (one of his instructors later commented the hapless
fellow
couldn't have spelt the word if his life depended on it).

The maneuver was in fact so precisely executed that the air traffic
controllers
at Dulles refused to believe the blip on their screen was a commercial
airliner.
Danielle O'Brian, one of the air traffic controllers at Dulles who
reported
seeing the aircraft at 9:25 said, "The speed, the maneuverability, the
way that
he turned, we all thought in the radar room, all of us experienced air
traffic
controllers, that that was a military plane."

And then, all of a sudden we have magic. Voila! Hanjour finds the
Pentagon
sitting squarely in his sights right before him.

But even that wasn't good enough for this fanatic Muslim kamikaze pilot.
You
see, he found that his "missile" was heading towards one of the most
densely
populated wings of the Pentagon-and one occupied by top military brass,
including the Secretary of Defense, Rumsfeld. Presumably in order to save
these
men's lives, he then executes a sweeping 270-degree turn and approaches
the
building from the opposite direction and aligns himself with the only
wing of
the Pentagon that was virtually uninhabited due to extensive renovations
that
were underway (there were some 120 civilians construction workers in that
wing
who were killed; their work included blast-proofing the outside wall of
that wing).

I shan't get into the aerodynamic impossibility of flying a large
commercial
jetliner 20 feet above the ground at over 400 MPH. A discussion on ground
effect
energy, tip vortex compression, downwash sheet reaction, wake turbulence,
and
jetblast effects are beyond the scope of this article (the 100,000-lb
jetblast
alone would have blown whole semi-trucks off the roads.)

Let it suffice to say that it is physically impossible to fly a
200,000-lb
airliner 20 feet above the ground at 400 MPH.

The author, a pilot and aeronautical engineer, challenges any pilot in
the world
to do so in any large high-speed aircraft that has a relatively low
wing-loading
(such as a commercial jet). I.e., to fly the craft at 400 MPH, 20 feet
above
ground in a flat trajectory over a distance of one mile.

Why the stipulation of 20 feet and a mile? There were several street
light poles
located up to a mile away from the Pentagon that were snapped-off by the
incoming aircraft; this suggests a low, flat trajectory during the final
pre-impact approach phase. Further, it is known that the craft impacted
the
Pentagon's ground floor. For purposes of reference: If a 757 were placed
on the
ground on its engine nacelles (I.e., gear retracted as in flight
profile), its
nose would be almost 20 above the ground! Ergo, for the aircraft to
impact the
ground floor of the Pentagon, Hanjour would have needed to have flown in
with
the engines buried 10-feet deep in the Pentagon lawn. Some pilot.

At any rate, why is such ultra-low-level flight aerodynamically
impossible?
Because the reactive force of the hugely powerful downwash sheet, coupled
with
the compressibility effects of the tip vortices, simply will not allow
the
aircraft to get any lower to the ground than approximately one half the
distance
of its wingspan-until speed is drastically reduced, which, of course, is
what
happens during normal landings.

In other words, if this were a Boeing 757 as reported, the plane could
not have
been flown below about 60 feet above ground at 400 MPH. (Such a maneuver
is
entirely within the performance envelope of aircraft with high
wing-loadings,
such as ground-attack fighters, the B1-B bomber, and Cruise missiles-and
the
Global Hawk.)

The very same navigational challenges mentioned above would have faced
the
pilots who flew the two 767s into the Twin Towers, in that they, too,
would have
had to have first found their targets. Again, these chaps, too,
miraculously
found themselves spot on course. And again, their "final approach" maneuv
ers at
over 500 MPH are simply far too incredible to have been executed by
pilots who
could not solo basic training aircraft.

Conclusion
The writers of the official storyline expect us to believe, that once the
flight
deck crews had been overpowered, and the hijackers "took control" of the
various
aircraft, their intended targets suddenly popped up in their windshields
as they
would have in some arcade game, and all that these fellows would have had
to do
was simply aim their airplanes at the buildings and fly into them. Most
people
who have been exposed only to the official storyline have never been on
the
flight deck of an airliner at altitude and looked at the outside world;
if they
had, they'd realize the absurdity of this kind of reasoning.

In reality, a clueless non-pilot would encounter almost insurmountable
difficulties in attempting to navigate and fly a 200,000-lb airliner into
a
building located on the ground, 7 miles below and hundreds of miles away
and out
of sight, and in an unknown direction, while flying at over 500 MPH - and
all
this under extremely stressful circumstances.

Complete text:
http://physics911.net/sagadevan.htm

In article M2%Rf.145850$H%4.115608@pd7tw2no,
"John Doe" wrote:

Hmmm one has to wonder just where he is going with this story?!
So either the hijackers were better pilots than this story would imply or,
they had help from someone else!
anyway that is the way "I" look at it. We may never know the "true" story of
9/11/01

*OR* -- it didn't take as much skill as the "9/11 Truth Movement" would
have us believe. I go with this one, talking from 46 years of pilot
experience.