by Nila Sagadevan
Nila Sagadevan is an
aeronautical engineer and a qualified pilot of heavy aircraft.
There are some who maintain that the mythical 9/11 hijackers, although proven to be too
incompetent to fly a little Cessna 172, had acquired the impressive skills that enabled
them to fly airliners by training in flight simulators.
What follows is an attempt to bury this myth once and for all, because I?ve heard this
ludicrous explanation bandied about, ad nauseam, 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.