# 9/11: How hard is it to hit a building at 500mph?

#### Mick West

Staff member
Maybe they can . . . maybe they can't . . . there are 767 experienced pilots that don't think novice pilots can at the speeds they did . . . so I will have to say this question is unanswered for me unless someone wants to demonstrate that ability . . . as I have suggested in several threads . . . so a remote pilot system . . . for me still . . . possible . ..

Since the pilots you cited also said that THEY could not do it, then how would remote control actually work?

#### George B

##### Extinct but not forgotten Staff Member
And here on this very thread there are experienced pilots who think they can.

I don't fly the larger jetliners in real life, but I believe Billzilla and TWCobra do.

In lack of a type rating and a large expensive airframe, I can easily show you this on a desktop flight simulator with it's obvious deficiencies, but I'm sure you wouldn't believe it unless you see a real airframe exceeding it's Vmo for your own eyes. In any case, the biggest issue with your remote pilot system theory is that it is overly far fetched, not to mention impractical given the circumstances. The biggest issue with the ideas cited by your experienced 767 pilots there is that I still have no idea how they got their mach 1.2 number from, which isn't even on the scale when I plug the numbers into my own flight computer, and second, I highly doubt those pilots have ever intentionally flown their aircraft past Vmo either. The former issue I'll defer to the ATPLs here, for I'm out of ideas.

EAS = A(sl) Ma [(Sq Root (P/Psl)]

A(sl) = is the standard speed of sound at 15 degrees C (661.47 Knots)
P= is static air pressure
P(sl)= Standard Second Level Pressure (1013.25 hPa)
Ma= Mach number???

This is something like the formula that they say they calculated the speed would be in Mach equivalent air speed at 22,000 feet for an air speed at 2,000 feet . . .

Mach 1 based on a standard day temperature at 22.000 feet = 609 knots true air speed.

.86 Mach = 522 knots

522 knots at 22,000 feet, in less dense air has the same effects as 369 knots at sea level in more dense air.

NOTE THE BIG DIFFERENCE OF AIR PRESSURE ACTING ON THE AIRFRAME.

Flight 175 reportedly reached the speed of 510 knots at sea level.

The max operating speed SET BY BOEING OF 360 KNOTS FOR LOWER ALTITUDES IS TOTALLY IGNORED.
THEY ALSO IGNORED THE EFFECTS OF AIR DENSITY AT LOWER COMPARED TO HIGHER ALTITUDES AND THE REASON THAT BOEING HAS TWO DIFFERENT MVOs FOR DIFFERENT ALTITUDES.

.86 MACH/586 KNOTS AT LOWER ALTITUDE HAS THE SAME EFFECT ON AN AIRCRAFT AS 805 KNOTS.
805 KNOTS = 1.32 MACH AT 22000 FEET = SUPERSONIC SPEED
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#### lee h oswald

##### Banned
Banned
Since the pilots you cited also said that THEY could not do it, then how would remote control actually work?

How long has auto-pilot been around? It's a computer flying a plane, isn't it? Very clever things, computers. And so much less emotional about killing themselves than people.

#### Mick West

Staff member
How long has auto-pilot been around? It's a computer flying a plane, isn't it? Very clever things, computers. And so much less emotional about killing themselves than people.

Sure it could be done, but the point is that flying by hand is very easy.

#### George B

##### Extinct but not forgotten Staff Member
Rico said:
In lack of a type rating and a large expensive airframe, I can easily show you this on a desktop flight simulator with it's obvious deficiencies, but I'm sure you wouldn't believe it unless you see a real airframe exceeding it's Vmo for your own eyes.

Bingo and see below . . .

In other words, Cockpit simulators are only required to simulate aerodynamic changes (not stress) within the aircraft envelope ("normally encountered in flight"), and even then, its not 100% realistic. After that, all bets are off. Simulators normally 'go red' and freeze within about 10% above red line. This is known as crash logic. Why was Bursill allegedly able to accelerate way beyond that? Watch the presentation and listen to the interview to find out. Many others are and have.

Content from External Source

#### George B

##### Extinct but not forgotten Staff Member
Rico said:
In any case, the biggest issue with your remote pilot system theory is that it is overly far fetched, not to mention impractical given the circumstances.

Why? Because someone would have to put it in each aircraft? And a GPS in the target area of the towers or paint the towers with a laser . . .

#### Mick West

Staff member
EAS = A(sl) Ma [(Sq Root (P/Psl)]

A(sl) = is the standard speed of sound at 15 degrees C (661.47 Knots)
P= is static air pressure
P(sl)= Standard Second Level Pressure (1013.25 hPa)
Ma= Mach number???

This is something like the formula that they say they calculated the speed would be in Mach equivalent air speed at 22,000 feet for an air speed at 2,000 feet . . .

Mach 1 based on a standard day temperature at 22.000 feet = 609 knots true air speed.

.86 Mach = 522 knots

522 knots at 22,000 feet, in less dense air has the same effects as 369 knots at sea level in more dense air.

NOTE THE BIG DIFFERENCE OF AIR PRESSURE ACTING ON THE AIRFRAME.

Flight 175 reportedly reached the speed of 510 knots at sea level.

The max operating speed SET BY BOEING OF 360 KNOTS FOR LOWER ALTITUDES IS TOTALLY IGNORED.
THEY ALSO IGNORED THE EFFECTS OF AIR DENSITY AT LOWER COMPARED TO HIGHER ALTITUDES AND THE REASON THAT BOEING HAS TWO DIFFERENT MVOs FOR DIFFERENT ALTITUDES.

.86 MACH/586 KNOTS AT LOWER ALTITUDE HAS THE SAME EFFECT ON AN AIRCRAFT AS 805 KNOTS.
805 KNOTS = 1.32 MACH AT 22000 FEET = SUPERSONIC SPEED
Content from External Source

Blimey, you'd think all aeronautics engineers would have noticed that this was an impossibly high speed.

#### Mick West

Staff member
Why? Because someone would have to put it in each aircraft? And a GPS in the target area of the towers or paint the towers with a laser . . .

Because it would have to work first time.

#### George B

##### Extinct but not forgotten Staff Member
Blimey, you'd think all aeronautics engineers would have noticed that this was an impossibly high speed.

That is what I think they are saying . . . Bingo . . .

#### lee h oswald

##### Banned
Banned
EAS = A(sl) Ma [(Sq Root (P/Psl)]

A(sl) = is the standard speed of sound at 15 degrees C (661.47 Knots)
P= is static air pressure
P(sl)= Standard Second Level Pressure (1013.25 hPa)
Ma= Mach number???

This is something like the formula that they say they calculated the speed would be in Mach equivalent air speed at 22,000 feet for an air speed at 2,000 feet . . .

Mach 1 based on a standard day temperature at 22.000 feet = 609 knots true air speed.

.86 Mach = 522 knots

522 knots at 22,000 feet, in less dense air has the same effects as 369 knots at sea level in more dense air.

NOTE THE BIG DIFFERENCE OF AIR PRESSURE ACTING ON THE AIRFRAME.

Flight 175 reportedly reached the speed of 510 knots at sea level.

The max operating speed SET BY BOEING OF 360 KNOTS FOR LOWER ALTITUDES IS TOTALLY IGNORED.
THEY ALSO IGNORED THE EFFECTS OF AIR DENSITY AT LOWER COMPARED TO HIGHER ALTITUDES AND THE REASON THAT BOEING HAS TWO DIFFERENT MVOs FOR DIFFERENT ALTITUDES.

.86 MACH/586 KNOTS AT LOWER ALTITUDE HAS THE SAME EFFECT ON AN AIRCRAFT AS 805 KNOTS.
805 KNOTS = 1.32 MACH AT 22000 FEET = SUPERSONIC SPEED
Content from External Source

Thanks, G, for highlighting again another gap in the account we've been given. It's yet another question mark, another tenaciously disputed part of the os - and by professional people with everything to lose. And yet another alarm sounding off. How many times do we hit the snooze button before getting up?

Ps I started this thread, apparently! You hi-jacker, you! Grrrr

#### George B

##### Extinct but not forgotten Staff Member
Because it would have to work first time.

Since it was only insurance . . . they were probably willing to take the chance . . . however, I am sure it was tested on missile systems before . . . the auto pilot was probably more capable than a cruise missile anyway . . . they probably computer simulated it like your flight simulator . . .

#### George B

##### Extinct but not forgotten Staff Member
Thanks, G, for highlighting again another gap in the account we've been given. It's yet another question mark, another tenaciously disputed part of the os - and by professional people with everything to lose. And yet another alarm sounding off. How many times do we hit the snooze button before getting up?

Ps I started this thread, apparently! You hi-jacker, you! Grrrr

I am perfectly willing to return it to you . . . however, Mick will have to make the change . . . LoL!!!

#### lee h oswald

##### Banned
Banned
Why? Because someone would have to put it in each aircraft? And a GPS in the target area of the towers or paint the towers with a laser . . .

Easy.

#### lee h oswald

##### Banned
Banned
I am perfectly willing to return it to you . . . however, Mick will have to make the change . . . LoL!!!

Don't worry, it wasn't mine in the first place! Just cuz me name's up there, don't mean nuthin'

#### lee h oswald

##### Banned
Banned
Sure it could be done, but the point is that flying by hand is very easy.

Not if you're faced with a big lump of certain death - I reckon your palms might get a bit sweaty.

#### TWCobra

##### Senior Member.
I think the EAS mention is causing confusion. United 175 was never supersonic. What the promoters of this video are saying is that the air loads on the aircraft were equivalent to those experienced at Mach 1.2 and since the aircraft cannot physically fly that fast, then it wasn't possible to fly at 513 knots at 1000 feet.

That is dubious reasoning. The aircraft was not flying at Mach 1.2. Therefore it was not experiencing compressibility symptoms caused by shock waves that occur at those Mach numbers. It was flying well below the Mach number where that begins to happen.

The effects of the air loads are different to those caused by shock waves over the wings. It is the physical loads caused by the pushing aside of the dense air at high speed. The Boeing test pilots needed to clear that part of the envelope to 360 knots. They would have cleared it however by flying substantially faster than that speed, by how much I don't know but let's say a safety margin of 20% and reporting the controllability they found at those speeds. Test Engineers would have had strain gauges rigged around the test airframe to measure the loads and the effects on the airframe.

That is all arcane stuff that Test pilots and Engineers train for. I think that the answers here can be found by asking a test pilot.

#### George B

##### Extinct but not forgotten Staff Member
I think the EAS mention is causing confusion. United 175 was never supersonic. What the promoters of this video are saying is that the air loads on the aircraft were equivalent to those experienced at Mach 1.2 and since the aircraft cannot physically fly that fast, then it wasn't possible to fly at 513 knots at 1000 feet.

That is dubious reasoning. The aircraft was not flying at Mach 1.2. Therefore it was not experiencing compressibility symptoms caused by shock waves that occur at those Mach numbers. It was flying well below the Mach number where that begins to happen.

The effects of the air loads are different to those caused by shock waves over the wings. It is the physical loads caused by the pushing aside of the dense air at high speed. The Boeing test pilots needed to clear that part of the envelope to 360 knots. They would have cleared it however by flying substantially faster than that speed, by how much I don't know but let's say a safety margin of 20% and reporting the controllability they found at those speeds. Test Engineers would have had strain gauges rigged around the test airframe to measure the loads and the effects on the airframe.

That is all arcane stuff that Test pilots and Engineers train for. I think that the answers here can be found by asking a test pilot.

Good let's find one . . . what do you think of John Lear . . . ?? LoL!!! Seems there is a speed at which there would not be enough thrust to continue to increase speed or control surfaces may have been affected . . .

#### Rico

##### Senior Member.
I wanted to talk about that in more detail, but I'm away from the computer. TWCobra completely nailed it though

#### lee h oswald

##### Banned
Banned
I think the EAS mention is causing confusion. United 175 was never supersonic. What the promoters of this video are saying is that the air loads on the aircraft were equivalent to those experienced at Mach 1.2 and since the aircraft cannot physically fly that fast, then it wasn't possible to fly at 513 knots at 1000 feet.

That is dubious reasoning. The aircraft was not flying at Mach 1.2. Therefore it was not experiencing compressibility symptoms caused by shock waves that occur at those Mach numbers. It was flying well below the Mach number where that begins to happen.

The effects of the air loads are different to those caused by shock waves over the wings. It is the physical loads caused by the pushing aside of the dense air at high speed. The Boeing test pilots needed to clear that part of the envelope to 360 knots. They would have cleared it however by flying substantially faster than that speed, by how much I don't know but let's say a safety margin of 20% and reporting the controllability they found at those speeds. Test Engineers would have had strain gauges rigged around the test airframe to measure the loads and the effects on the airframe.

That is all arcane stuff that Test pilots and Engineers train for. I think that the answers here can be found by asking a test pilot.

Yeah yeah, but now imagine you're aiming your aircraft at certain death - tearing along at a serious rate of knots, so your ship's shaking like a shaky thing that ain't too happy.....how does that feel?

#### Mick West

Staff member
Yeah yeah, but now imagine you're aiming your aircraft at certain death - tearing along at a serious rate of knots, so your ship's shaking like a shaky thing that ain't too happy.....how does that feel?

Hmm, "they would be too scared" does not really strike me as a convincing argument. All they have to do is aim, and accelerate towards martyrdom.

#### lee h oswald

##### Banned
Banned
Good let's find one . . . what do you think of John Lear . . . ?? LoL!!! Seems there is a speed at which there would not be enough thrust to continue to increase speed or control surfaces may have been affected . . .

Good let's find one . . . what do you think of John Lear . . . ??

Still chuckling

Seems there is a speed at which there would not be enough thrust to continue to increase speed or control surfaces may have been affected . . .

That's a polite way of putting it. Wings tearing off (wind tunnel video) is a pretty serious control surface being affected.
And there's definitely a point at which the vehicle can go no faster - just like any car. When your foot's on the floor, that's it.

#### George B

##### Extinct but not forgotten Staff Member
Hmm, "they would be too scared" does not really strike me as a convincing argument. All they have to do is aim, and accelerate towards martyrdom.

Or faint from fear. . . why take chances . . . if you are going to stage the greatest crime in modern history and blame it on some extremists . . . make sure they do it right . . . it is a bit different than simply pushing a detonator on a vest bomb . . .

Staff member

#### Mick West

Staff member
And there's definitely a point at which the vehicle can go no faster - just like any car. When your foot's on the floor, that's it.

Unless you come to a downhill slope. Like UA175 was on.

#### George B

##### Extinct but not forgotten Staff Member
Unless you come to a downhill slope. Like UA175 was on.

Sorry, even flight 990 reached a terminal air speed . . . and it was at 22,000 feet that is a long way from sea level . . . unless you think they were trying to pull up at that point . . .

#### lee h oswald

##### Banned
Banned
Hmm, "they would be too scared" does not really strike me as a convincing argument. All they have to do is aim, and accelerate towards martyrdom.

That's borderline racist, or maybe the word's 'Islamist'? Lol! Oh, no, it's Islamophobic. Think about those things you say. Human beings you're talking about. Same as you. They liked a bit of coke, lap-dancing and alcohol, too. That's how committed they were to keeping their cover - because they were really just hanging out to die for a promise of 72 virgins. You couldn't write that shit. No-one would believe it.

#### George B

##### Extinct but not forgotten Staff Member
Have a look at this Boeing 787 flutter testing:
http://www.boeing.com/Features/2010/04/bca_telemetry_room_04_26_10.html

Don't you think these guys would know if it's possible or not? Are there not hundreds, if not thousands of people who would know what would happen if the design envelope was exceeded?

One would think so . . . but they seem to be very quiet . . . why don't you see if you can find one to comment on these issues about a 767-200??

#### lee h oswald

##### Banned
Banned
Sorry, even flight 990 reached a terminal air speed . . . and it was at 22,000 feet that is a long way from sea level . . . unless you think they were trying to pull up at that point . . .

Exactly, there's a point at which the thrust/drag situation prevents any more speed. And at 22k in a dive - it's good comparative data, it seems.

#### lee h oswald

##### Banned
Banned
Unless you come to a downhill slope. Like UA175 was on.

Maximum speed is maximum speed.

#### TWCobra

##### Senior Member.
Good let's find one . . . what do you think of John Lear . . . ?? LoL!!! Seems there is a speed at which there would not be enough thrust to continue to increase speed or control surfaces may have been affected . . .

John Lear?... err no. I was thinking of a mate of mine who graduated Dux of his class at Patuxent River. He did the helicopter test course but would be able to find the references for this. He is a former 767 captain as well. Watch this space.

#### lee h oswald

##### Banned
Banned
One would think so . . . but they seem to be very quiet . . . why don't you see if you can find one to comment on these issues about a 767-200??

I second that. Find a current live Boeing employee, or even a former one, who will speak about it. Make an foia?

#### George B

##### Extinct but not forgotten Staff Member
Why? Because someone would have to put it in each aircraft? And a GPS in the target area of the towers or paint the towers with a laser . . .

Just another thought . . . what if the Hi-Jackers were instructed to install the remote control device themselves . . . just saying . . . they would have the time and motive . . .

#### lee h oswald

##### Banned
Banned
Or faint from fear. . . why take chances . . . if you are going to stage the greatest crime in modern history and blame it on some extremists . . . make sure they do it right . . . it is a bit different than simply pushing a detonator on a vest bomb . . .

G, I presume from your work of many years, that you have seen how computers can perform intricate tasks, would some of those be tasks that you could describe as 'beyond' human capability eg in being dextrous, or delicate - could you describe something you have experience of in relation to this?

#### Met Watch

##### Moderator
Just another thought . . . what if the Hi-Jackers were instructed to install the remote control device themselves . . . just saying . . . they would have the time and motive . . .

While they're already on the plane? This only makes sense if you think a novice pilot couldn't possibly fly a plane at over 500 mph (below the maximum operating speed) into a 260 ft wide target that you could see coming 20 miles away, if not more.

I suggest you ask your questions to whoever Cobra can find - I'm sure he'll answer them with as much detail as you want.

#### Cairenn

##### Senior Member.
Why is admitting that the hijackers considered theirselves martyrs be Islam phobic? That was what they considered their selves. FACT

#### George B

##### Extinct but not forgotten Staff Member
While they're already on the plane? This only makes sense if you think a novice pilot couldn't possibly fly a plane at over 500 mph (below the maximum operating speed) into a 260 ft wide target that you could see coming 20 miles away, if not more.

I suggest you ask your questions to whoever Cobra can find - I'm sure he'll answer them with as much detail as you want.
We will . . .

#### Mick West

Staff member
Maximum speed is maximum speed.

Well, it depends on what is limiting the speed. If you are just talking about wind resistance, then you can always go faster by increasing acceleration, either by thrust, or angling down.

Maximum speed is increased by descending, as you've got gravity on your side. I'm not sure how much though, as it gets harder to keep the nose down as you go faster. I think the actual maximum speed would be in some kind of powered death spiral.

#### George B

##### Extinct but not forgotten Staff Member
G, I presume from your work of many years, that you have seen how computers can perform intricate tasks, would some of those be tasks that you could describe as 'beyond' human capability eg in being dextrous, or delicate - could you describe something you have experience of in relation to this?
Lee, let me think about that one . . . I have to run . . . but yes, robotics would be an example where a computer can easily out perform a human almost every time. . .

#### Mick West

Staff member
Lee, let me think about that one . . . I have to run . . . but yes, robotics would be an example where a computer can easily out perform a human almost every time. . .

U

#### Unregistered

##### Guest
This is better than Tosh.0, from a tech stand point. George B. is the only one keeping it in the ball park of reality. For starters GPS uses RADIO WAVES, which can not penetrate a FARADAY CAGE. Remember the communication system was down in the N tower, b/c they had to have a relay system working INSIDE. It also PREVENTED anyone form the 1st "plane strike" from relaying conditions (humm why would that be necessary??). Communications from the S tower "Small pockets of fire", THAT IS IT. OHH, and the S tower FELL 1st, hummm.
Wing tips have been known to come off in NORMAL flight conditions: http://youtu.be/6h8eVsLGm7s?t=1m17s
<iframe width="854" height="510" src="http://www.youtube.com/embed/1hkv-X0Kp34" frameborder="0" allowfullscreen></iframe>
But somehow they don't come off when striking a structural steel column, hummm
This footage was cropped and cloned 5 different ways, and claimed by 5 different people. Names can be found in September Clues:
<iframe width="854" height="510" src="http://www.youtube.com/embed/tywMLqVcBO4" frameborder="0" allowfullscreen></iframe>
So someone please clarify, how is this justified as a "dive"? Notice how the shadowing is not consistent w/ other POV.
Maybe it just "fell" from 31K ft: http://youtu.be/jdXGSefI6pM

Here is a structural engineer who states "could knock out A column": http://youtu.be/MY7BCXew0UI?t=5m52s
Notice ESB has columns 30' between centers(the hole in the concrete was 18'), and NO STRUCTURAL BEAMS WERE SHEARED!!
Bonus: the very next guy is Frank DeMartini, WTC project construction manager who just happen to "disappear" that very day, how inconvenient. Hummm

So the only two questions are:

1. Does the 767 have the thrust available to fly that fast at 513 KIAS at 1000 feet? and

2. Would the aerodynamic loads of flying at that speed and height cause break-up of the airframe?

Q1. In my opinion, most definitely. The aircraft has large amounts of excess thrust at low altitude.

Q2. I cannot answer that question from any data I have seen, but if you accept that flight 175 was an unmodified 767, apparently it can.
[/URL]

It "has large amounts of excess thrust" b/c more fuel (on the oxygen side of the equation) is available to create power. But the throughput (number of molecules it can process) is still the same, so it will run out of "excess thrust" very quickly. It's called cavitation.

Great to see good questions being proposed, but still the wrong questions.

Cartman "THAT'S MY PIE KITTY"

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