Dispelling Myths: The "Impossible Maneuver" (1 Viewer)

[Deuce]

Lately I've been seeing Flight 77's final maneuver described as "impossible" several times. This has been a long-running thing, but it's just resurfaced again more recently. The maneuver being supposedly impossible is used as evidence that the "official story" is a lie. The purpose of this thread is to discuss that claim, because if the maneuver is actually easy, the claim falls apart.

As a professional pilot of many years, I feel I am qualified to discuss this in detail.

To analyze the "official story maneuver," we do have to stick to the maneuver as described in official reports. Including the flight data recorder. Now, I'm aware some believe the FDR track is faked. Irrelevant for the purposes of this thread. The "official maneuver" is claimed to be impossible, so only analysis of the depicted maneuver can be used to assess this claim.

Here is an animation from the NTSB created from the flight data recorder. Note that the video is like 90 minutes long, skip to 1:18 as that's about where the maneuver begins.



Notice the bank angle indicator. (artificial horizon with the purple sky) At no point during the turn does it exceed the 45 degree mark. It only briefly hits about ~40 degrees a couple times, mostly sticking to ~30 degrees.

30 degrees is on the high side of normal, but it's entirely normal. Every student pilot practices turns at 45 degrees. 45 degree bank angle results in roughly 1.3 Gs. Again, entirely normal.

Here's the track:

The red circled area indicates about where the "final approach" straight-ish line begins. That's about five miles away. You can see the diameter of the turn is about that much. This is a wide, level turn. A trivial, every-day maneuver.

The final descent is a straight-line descent.

Airspeed stays within aircraft design limits (360 knots "Vmo," or maximum operating speed) until 13:37:25 EDT. (1:21:49 in the linked video) FDR data terminates at 13:37:44, only nineteen seconds later.

 

[mike2810]

Should be interesting to see what some of the posts say.
For me, this is just a rehash of a topic that has long been debated.

Until proven otherwise one passenger jet crashed in Shankville, one hit WTC1, one hit WTC2 and one hit the Pentagon.

 

[Deuce]

On Vmo.

Note that this post discusses some of the technical details of aircraft limitations and certifications. If that doesn't interest you, then skip. I'm a nerd so I do find it interesting.

"Vmo +90" is tossed about sometimes, meaning the aircraft exceeded the operating limit by 90 knots. This is a lot! But let's analyze Vmo a bit.

Now, it's important to note that no limitation in aviation is a "things break at this point" limitation. There's always a buffer, and a substantial one. Any limitation needs to account for long-term airframe fatigue and just a general safety buffer. Both, I mean. Long-term fatigue and a buffer on top of it. If the wings snap off on a brand new airplane at speed X, a 20 year old airframe may not hold up to the same stress. Also, repeated exposures to high speeds may reduce the eventual failure speed.

Vmo stands for "Maximum Operating speed." It's a design speed limitation roughly equivalent to "Never Exceed" speed found on smaller trainer aircraft, in that the purpose is for pilots to, well, never exceed it. A loud annoying horn sounds when you do. Ask any jet pilot. And I do mean any jet pilot because literally all of us have done it at some point. For the 767 that was Flight 77, this is 360 knots. The final recorded speed was about 100 knots faster than this. Quite a bit!

But.

This speed isn't an "airframe failure" speed. It's a design limitation for long-term use. As an example, the first jet I flew was a small Citation jet. It had two different Vmo's for different altitudes. Above 8000 feet it was 272 knots, below 8000 it was 260 knots. Why the difference?

Birds.

Yep. Bird strike protection. The windshield was rated for 260 knots for impact with whatever the FAA Standard Bird is. And thankfully birds recognize their allowed altitude of 8000 feet. (highest recorded bird strike is 37000 feet!)

For analyzing the perils of high-speed flight, another speed is good to look at: Mmo. This is Maximum Operating speed in Mach, rather than knots. It's relative to the speed of sound, which changes on various conditions. This speed is important because the Vmo mentioned above is measured in indicated airspeed, and as you get higher your indicated airspeed decreases for a given "actual" speed. (we call it True Airspeed) This is because air pressure is used to measure airspeed, and that pressure decreases as you go up. Mmo is helpful because the high-speed problems all occur based on your position relative to the speed of sound. Close to the speed of sound, shockwaves start to form on the leading edges with all kinds of issues for planes not designed to deal with them.

For the 767, Mmo is .86. At sea level, this corresponds to ~567 knots indicated airspeed. The Pentagon is slightly above sea level, but not enough to really matter here. I also haven't adjusted for whatever the temperature was that day, but again not a huge factor. Bottom line: Flight 77 was about a hundred knots slower than its maximum rated mach speed, which is where most of the problems of high-speed flight occur.

Another speed is worthy of discussion here, one many pilots wont even be aware of. Vd. Vd is a speed used purely in flight testing. It's the maximum demonstrated airspeed for the airframe. The 767 has a Vd of 420 knots. This means under actual testing conditions, the plane was put into a dive of 420 knots and did not suffer any structural damage. Flight 77 exceeded a real-world test speed by only about ten percent. Also important: 420 knots was hit at 13:37:36. An actual, real-world test speed was only exceeded for eight seconds.

Am I really to believe ten percent above an actually-flown speed will cause some catastrophic structural failure?

Now, I am not saying 100 knots over red line is safe. It's not. In fact, it's a really stupid thing to do and no pilot should do it. It will reduce the lifetime of your airframe and if you keep doing it something may very well break. Also, your mechanic may strangle you. But a man intent on committing murder-suicide-by-airplane in the name of an invisible sky wizard isn't exactly concerned with that.

edit: extra notes on Vd. The requirement is a 1.5 G pull out from the dive, and by law must be at least 20% over Vmo)

 

[Deuce]

Hitting the Target

It is claimed that actually striking the target requires some kind of pinpoint accuracy not found at the hands of an inexperienced, and reportedly below-average pilot like Hani.

I disagree. This was a straight-line descent towards a target. The easiest thing in the world to do is point the nose at something and hit it. Landing is precision work. Landing requires smooth inputs and good timing. Landing requires practice. Landing is hard. Crashing is ****in easy! I've had Boy Scout troops show up to tour the airport in my instructing days. We'd stick them in our simulator and have them play around. Even those children could hit a runway. (we turned off crash detection so they feel like they actually landed successfully. cute as hell)

But some references:

The Pentagon is 77 feet tall according to PilotsFor911truth.org. Standard threshold crossing height on a runway is 35 feet. This means the Pentagon had twice the "margin of error" compared to a normal approach to landing, vertically... and this doesn't account for its depth. Even being slightly high and missing the front end, you still have the entire length of the structure to impact the roof.

Each side is 921 feet long, I think the widest runway I've ever landed on is 200 feet. So, quadruple the width of even a large runway.

The Pentagon boasts being the world's largest office building. It's 583 acres. This is not a hard target to hit.

 

[Deuce]

Errata: Flight 77 was a 757, not a 767. I mind-merged the two airframes as I was looking through design documents for both. The 757 and 767 share the same type-rating, all of the listed numbers are applicable to both airframes.

 

[Deuce]

G-loading:

As shown above, "the turn" never exceeded even two g's. It was a trivial ~40 degree bank angle.

The pull out from the dive is where the highest g-loading occurred.



As we can see, ~2.2 G's is the highest loading found. For a transport-category aircraft like the 757, the legal limit is 2.5gs. Actual physical testing must exceed this by at least 50%.

Flight 77 never exceeded the legal g-loading limit, much less actual testing loads where they induce structural failure. Here's a fun video of that testing on the 777!

 

[Deuce]

If there are any other objections to the depicted maneuver, feel free to post them here.

Claims about the validity of the FDR will not be addressed in this thread. Another thread, maybe another time. However, feel free to list some FDR objections briefly so I can make a list of points to address should I do a thread on that.

 

[Thoreau72]

Deuce

The Vmo +90 figure comes from the analysis done by Stutt and Legge, one of which is now deceased. So it's not my number, it's their number, and they were both big supporters of the official story.

The data you include here is from NTSB data, and that was the data supposedly analyzed and included by Stuff and Legge, and that is the same data that was examined by Cimino, who found it to be fake and forged, as the data provided him by NTSB was not even assigned to an airframe.

So the point is that all NTSB information is suspect. So your thread is essentially based upon made up data, but let's discuss it anyway. Oh wait, we can't discuss it already, because you just noted that you are unwilling unable to address those issues. Why am I not surprised.

I suppose you're also unable and unwilling to discuss Hoffman Aviation and any statements by any flight instructors who supposedly flew with Hani? And I presume you are also unwilling to discuss anything about the ability of pilots to transition from Cessnas to Boeings? And I think you've made it clear here before that you are also unwilling to discuss the specifics of your own licenses and experience by type, just for perspective. And haven't you said before that you do not hold CFI, but you do have some bit of time in lessons in an R-22?

I have flown several different airplanes at and above the redline speed, but never more than maybe 15-20 knots. As I recall you've mentioned that you too have exceeded Vmo, but by a small margin and also only once or twice?

Do you have the CFI, and is it asking too much to find out how much time instructing you have, so that I can better judge the OP? That, so I can judge your ability as CFI to judge the abilities of young 350 hour pilots as was Hani?

 

[Deuce]

Deuce

The Vmo +90 figure comes from the analysis done by Stutt and Legge, one of which is now deceased. So it's not my number, it's their number, and they were both big supporters of the official story.

The data you include here is from NTSB data, and that was the data supposedly analyzed and included by Stuff and Legge, and that is the same data that was examined by Cimino, who found it to be fake and forged, as the data provided him by NTSB was not even assigned to an airframe.

So the point is that all NTSB information is suspect. So your thread is essentially based upon made up data, but let's discuss it anyway. Oh wait, we can't discuss it already, because you just noted that you are unwilling unable to address those issues. Why am I not surprised.

Already addressed. This thread is specifically about the depicted maneuver. You have claimed the depicted maneuver is impossible, so we must analyze the depicted maneuver. Claims of faked depictions will be for another thread. I'll note down the "not even assigned to an airframe" criticism for later. Thank you.

I suppose you're also unable and unwilling to discuss Hoffman Aviation and any statements by any flight instructors who supposedly flew with Hani? And I presume you are also unwilling to discuss anything about the ability of pilots to transition from Cessnas to Boeings?

And I think you've made it clear here before that you are also unwilling to discuss the specifics of your own licenses and experience by type, just for perspective.

Wrong. I've discussed that several times. About 6000 hours total time. ATP, CFI, two type ratings. 10 years instructing, about three in jets. Taught formal classroom for aerodynamics and avionics.

And haven't you said before that you do not hold CFI, but you do have some bit of time in lessons in an R-22?

You're clearly confusing me with someone else. I hold a flight instructor certificate. I was an active, full-time flight instructor for about a decade. I was chief flight instructor at two different flight schools.

I flew an R22 exactly once. Helicopters are for nutters.

I have flown several different airplanes at and above the redline speed, but never more than maybe 15-20 knots. As I recall you've mentioned that you too have exceeded Vmo, but by a small margin and also only once or twice?

Relevance?

Do you have the CFI, and is it asking too much to find out how much time instructing you have, so that I can better judge the OP? That, so I can judge your ability as CFI to judge the abilities of young 350 hour pilots as was Hani?

Above. 10 years as an instructor. I am well-qualified to assess inexperienced pilots.

You've dodged literally every point made in the thread. Hitting a target the size of the Pentagon, boasted as the world's largest office building, is easy. But hey, instead of addressing that you can keep trying to make this about me. Go ahead. Keep posting about me.

 

[Thoreau72]

No, as I have posted several times here over the years that I say the maneuver IN CONTEXT is impossible.

As I've mentioned here before several times, I could do the maneuver in my T-6 all day long, and have fun doing it.

But it was not me, it was Hani, first time in a Boeing. See the difference?

 

[Deuce]

No, as I have posted several times here over the years that I say the maneuver IN CONTEXT is impossible.

As I've mentioned here before several times, I could do the maneuver in my T-6 all day long, and have fun doing it.

But it was not me, it was Hani, first time in a Boeing. See the difference?

The "maneuver" was a level, wide turn never exceeding 40 degrees of bank. Any idiot can do that, even in a Boeing. He didn't do it precisely or smoothly, altitude fluctuated up and down a few hundred feet. Again, something even a rookie pilot can do.

Then, it was a straight-line descent. Point nose at thing, run into thing. Not difficult.

The video in the first post proves that this "maneuver" was not remotely challlenging. I want you to watch it from the timestamp I showed you. Then I want you to point out which part demonstrates some superior piloting skill. (a timestamp would help)

 

[mike2810]

Deuce:

If you noticed the P4911T or CIT supporters are not responding to your posts.

 

[camlok]

Deuce:

If you noticed the P4911T or CIT supporters are not responding to your posts.

It was only posted "yesterday", whatever that means according to debatepolitics time clock.

Always the hypocrisy, mike. As I have mentioned many times you USOCT supporters never respond to any of the myriad impossibilities of the crazy theory you support, the one with no evidence.

Let's let Deuce and Thoreau discuss this without any of your usual hypocrisy. Let the chips fall where they may!

 

[mike2810]

It was only posted "yesterday", whatever that means according to debatepolitics time clock.

Always the hypocrisy, mike. As I have mentioned many times you USOCT supporters never respond to any of the myriad impossibilities of the crazy theory you support, the one with no evidence.

Let's let Deuce and Thoreau discuss this without any of your usual hypocrisy. Let the chips fall where they may!

The hypocrisy is yours. I have stated many times any explanation needs to stand on its own merits. You fail to back up your statements.

https://www.ntsb.gov/about/Documents/Flight_Path_Study_AA77.pdf


Conspiracy Nation: myths, madness, and the ?truth? about 9/11

"Reality: The cabal’s feats did not require in-depth technical knowledge or a high degree of skill.* The attackers, as private pilots, were completely out of their league in the cockpits of those 757s and 767s; however they were not setting out to perform single-engine missed approaches or Category-3 instrument landings with a failed hydraulic system – or to land at all.* They were setting out to steer an already airborne jetliner, in perfect weather, into the side of a building.* Though, for good measure, Mohammed Atta and at least one other member of his group did buy several hours of simulator training on a Boeing 727 (this was not the same type of jet used in the attacks, but it didn’t need to be).* Additionally they obtained manuals and instructional videos for the 757 and 767, available from aviation supply shops.
Hani Hanjour’s flying was exceptional only in its recklessness.* If anything, his loops and spirals above the nation’s capital revealed him to be exactly the ****ty pilot he by all accounts was.* To hit the Pentagon squarely he needed only a bit of luck, and he got it.* Striking a stationary object — even a large one with five beckoning sides — at high speed and from a steep angle is very difficult.* To make the job easier, he came in obliquely, tearing down light poles as he roared across the Pentagon’s lawn.* If he’d flown the same profile ten times, seven of them he’d probably have tumbled short of the target or overflown it entirely.
As for those partisan pilots known to chime in on websites, take them with a grain of salt.* As somebody who flies 757 and 767s for a living, I think my testimony carries some weight.* Ask around and you’ll discover that the majority of professional pilots feel the way I do."

If you believe Flight 77 did not hit the Pentagon, then please provide your explanation with sources.

 

[camlok]

Lately I've been seeing Flight 77's final maneuver described as "impossible" several times. This has been a long-running thing, but it's just resurfaced again more recently. The maneuver being supposedly impossible is used as evidence that the "official story" is a lie. The purpose of this thread is to discuss that claim, because if the maneuver is actually easy, the claim falls apart.

The corollary to your assertion is, of course, "If the maneuver is NOT actually easy, the USOCT, aka the "official theory"is false. Do you agree?

But regardless, your initial assertion is also false. Even if such a maneuver is possible for the terrible pilot Hani Hanjour was, it in no way brings the "official story" into a position of being less than a lie. There is just way too many other impossibilities in the USOCT for it to be true.

But let's put that aside for now. On with Hani Hanjour and the ease with which I could become a jumbo jet pilot tomorrow.

As a professional pilot of many years, I feel I am qualified to discuss this in detail.

To analyze the "official story maneuver," we do have to stick to the maneuver as described in official reports. Including the flight data recorder. Now, I'm aware some believe the FDR track is faked. Irrelevant for the purposes of this thread. The "official maneuver" is claimed to be impossible, so only analysis of the depicted maneuver can be used to assess this claim.

It is totally unprofessional of you, not to mention also totally dishonest of you to think that you can determine the parameters of this discussion.

Here is an animation from the NTSB created from the flight data recorder. Note that the video is like 90 minutes long, skip to 1:18 as that's about where the maneuver begins.

Why have you chosen the NTSB animation, Deuce?

I am calling almost total BS or a large measure of BS, Deuce, for a number of reasons.

1. There is no proof that you say you are what you say you are, "a professional pilot of many years". Why would we take the word of a person who has done nothing but deceive in every manner possible?

Why would we take the word of a person who has engaged in covert childish behavior with other individuals in concerted effort to distract and divert from the science and the truth.

2. Your behavior has been nowhere near professional in any of your posts before this one. That is why I found this one so shocking and disturbing. It was surreal; after seeing Mr Hyde for so many months, suddenly a new, sane reasonable Dr Jekkyl suddenly appeared and he actually was very convincing, until one did a modicum of research.

Don't take this as a complete dismissal of your intended point. We should and I hope we will discuss it. But it just seems so weird that you make this pronouncement of professionalism right out of the blue after so many months of such unprofessional conduct.

 

[Thoreau72]

The "maneuver" was a level, wide turn never exceeding 40 degrees of bank. Any idiot can do that, even in a Boeing. He didn't do it precisely or smoothly, altitude fluctuated up and down a few hundred feet. Again, something even a rookie pilot can do.

Then, it was a straight-line descent. Point nose at thing, run into thing. Not difficult.

The video in the first post proves that this "maneuver" was not remotely challlenging. I want you to watch it from the timestamp I showed you. Then I want you to point out which part demonstrates some superior piloting skill. (a timestamp would help)

Something about your answers make it seem like you a simulator pilot/expert who has never flown a real airplane for a living. But I'm going to view this simulation again. Simulations created from contrived information is really wasting time, but I'll play along.

How much instruction have you given to 300 hour pilots? Either in a sim or in a real airplane? I suspect that info won't be forthcoming.

In something over 11,000 hours, I have something over 3000 hours of giving dual. I don't believe for 1 minute that anybody, including Hani The Magnificent, could slit throats and assume command of a 757 for the first time in his life and fly that maneuver as interpreted by Stutt and Legge.

Neither do a handful of line pilots in the type, sim.

 

[Thoreau72]

Well I watched it again Deuce, and I still say you are a sim guy, and you don't fly airplanes much.

Which type ratings do you hold in your regular flying job, or is that too much?

I'm typed Learjet and Citation 500.

Your sim has Hani at 460 knots and as they determined many years ago, the NTSB data does not go below 180 feet altitude. As Cimino pointed out years ago, the whole damn thing is forged.

Keep consuming that bit o' forgery Deuce, it becomes you.

 

[mike2810]

Something about your answers make it seem like you a simulator pilot/expert who has never flown a real airplane for a living. But I'm going to view this simulation again. Simulations created from contrived information is really wasting time, but I'll play along.

How much instruction have you given to 300 hour pilots? Either in a sim or in a real airplane? I suspect that info won't be forthcoming.

In something over 11,000 hours, I have something over 3000 hours of giving dual. I don't believe for 1 minute that anybody, including Hani The Magnificent, could slit throats and assume command of a 757 for the first time in his life and fly that maneuver as interpreted by Stutt and Legge.

Neither do a handful of line pilots in the type, sim.

What was that you posted in another thread about when people attack the creditability of a person? ".......is attacked because when the debate is lost, slander becomes the tool of the loser"

 

[camlok]

What was that you posted in another thread about when people attack the creditability of a person? ".......is attacked because when the debate is lost, slander becomes the tool of the loser"

Your stunning hypocrisy, AGAIN, MIKE!

Consider just your last number of posts in the thread where I pointed out your attack credentials.

 

[Thoreau72]

What was that you posted in another thread about when people attack the creditability of a person? ".......is attacked because when the debate is lost, slander becomes the tool of the loser"

Deuce is probably out flying the line somewhere. I'm sure he will get back to offer his credentials and other reasons to help understand why he thinks as he does.

Most pilots I hang with are happy to offer ratings and experience, so I'm sure Deuce will eventually provide something. If he were able to examine the maneuver in context it would be much better from the perspective of rational public dialogue.

Sure the maneuver itself would be a cake walk in an F-16 operated by an experienced pilot, but the same maneuver in a transport category aircraft flown by a completely inexperienced pilot is a whole different type of orange.

 

[mike2810]

Deuce is probably out flying the line somewhere. I'm sure he will get back to offer his credentials and other reasons to help understand why he thinks as he does.

Most pilots I hang with are happy to offer ratings and experience, so I'm sure Deuce will eventually provide something. If he were able to examine the maneuver in context it would be much better from the perspective of rational public dialogue.

Sure the maneuver itself would be a cake walk in an F-16 operated by an experienced pilot, but the same maneuver in a transport category aircraft flown by a completely inexperienced pilot is a whole different type of orange.

You know the problem with the internet postings. Anyone can post what they want. Heck, someone could post they are a PHD nuclear scientist. Someone can post they are a pilot.

One has to look at past posting to determine creditability and the sources they use.

 

[camlok]

The following is yet another grand illustration how things went from truthfulness on 911 and shortly thereafter to full shutdown, ie. no substantive discussion allowed.

"To hit something with an airplane is easy only if you have been flying for 20 years."
- Boeing 767 pilot quoted in the Boston Globe

"The conspiracy apparently did not include a surplus of skilled pilots."
- The Washington Post

In the days after 9/11, numerous pilots and aviation experts commented on the elaborate maneuvers performed by the aircraft in the terrorist attacks, and the advanced skills that would have been necessary to navigate those aircraft into their targets. The men flying the planes must have been "highly skilled pilots" and "extremely knowledgeable and capable aviators," who were "probably military trained," these experts said.

And yet the four alleged hijackers who were supposedly flying the aircraft were amateur pilots, who had learned to fly in small propeller planes, and were described by their instructors as having had only "average" or even "very poor" piloting skills. But on their first attempt at flying jet aircraft, on September 11, 2001, these men were supposedly able to fly Boeing 757s and 767s at altitudes of tens of thousands of feet, without any assistance from air traffic control.

...

EXPERTS SAID HIJACKERS 'MUST HAVE BEEN EXPERIENCED PILOTS'
Numerous experts commented that the hijackers who flew the aircraft in the 9/11 attacks must have been highly trained and skillful pilots. Tony Ferrante, the head of the Federal Aviation Administration's investigations division, spent several days after 9/11 carefully piecing together the movements of the four aircraft targeted in the attacks. According to author Pamela Freni, Ferrante's "hair stood on end when he realized the precision with which all four airplanes had moved toward their targets." Ferrante said, "It was almost as though it was choreographed," and explained, "It's not as easy as it looks to do what [the hijackers] did at 500 miles an hour." [1]


The 9/11 Hijackers: Amateur Aviators Who Became Super-Pilots on September 11 | 911Blogger.com

 

[camlok]

You know the problem with the internet postings. Anyone can post what they want. Heck, someone could post they are a PHD nuclear scientist. Someone can post they are a pilot.

One has to look at past posting to determine creditability and the sources they use.

Exactly, mike, and you fail in most every regard, as do your fellow distracters/diversionists.

Your "sources", if you folks have ever mentioned any by name, I've forgotten because you are too ashamed to put them and their "credentials" forward.

You folks can't discuss anything related to the science or events of 911 because, one, you are scared you will put your foot in your mouths, as y'all have done numerous times; two, you focus on your distractions/diversions when you are faced with the myriad impossibilities in the wacky conspiracy theory y'all support, the USGOCT.

You've just come off supporting the crazy idea that steel framed towers have collapse features built right into them.

 

[mike2810]

The following is yet another grand illustration how things went from truthfulness on 911 and shortly thereafter to full shutdown, ie. no substantive discussion allowed.

So what hit WTC 1, 2, and the Pentagon? Some poster stated you are a no planer believer. Is that correct?

Lay out your evidence.

 

[mike2810]

Exactly, mike, and you fail in most every regard, as do your fellow distracters/diversionists.

You folks can't discuss anything related to the science or events of 911 because, one, you are scared you will put your foot in your mouths, as y'all have done numerous times; two, you focus on your distractions/diversions when you are faced with the myriad impossibilities in the wacky conspiracy theory y'all support, the USGOCT.

You've just come off supporting the crazy idea that steel framed towers have collapse features built right into them.

Ah. No.

You once again misrepresent what I post. Good job.