ISRAEL’S PRE-ELECTION ATTEMPT TO DEFLECT A NEW 9/11 INVESTIGATION
Nila Sagadevan is an aeronautical engineer and a pilot. 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 by themselves 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, and 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 ‘lost it’ 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.
“Regarding your comments on flight simulators, several of my colleagues and I have tried to simulate the ‘hijacker’s’ final approach maneuvers into the towers on our company 767 simulator. We tried repeated tight, steeply banked 180 turns at 500 mph followed by a fast rollout and lineup with a tall building. More than two-thirds of those who attempted the maneuver failed to make a ‘hit’. How these rookies who couldn’t fly a trainer pulled this off is beyond comprehension.”
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 about fifteen feet 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 in the Pentagon lawn. (Editor’s note: Grass on the lawn of the Pentagon was intact.)
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 Boeing 757 would have struck the top half of the upper floor of the Pentagon and tumbled over the building while disintegrating. At 400 mph, some sections of fuselage would have landed as far as a half mile away.
- The aircraft would have skipped across the top of the Pentagon like a stone on a pond, shedding its engines and would have left a debris field extending as much as a mile from the initial impact.