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

The autopilots on airliners are designed to give Aunt Martha in seat 46b a smooth ride. They are generally smoother in operation, particularly with the application of lateral G forces, than the average pilot.
If you want to take evasive action, such as a TCAS climb or descent, the first memory item is "autopilot -disengage" because the AP simply does not react quickly enough.
Makes sense . . .
 
To a large extent, cruise control on a car is similar. It is great to keep the speed constant so your passengers don't get car sick, but once you encounter traffic or weather, it needs to be off.
 

POLL: Could pilots with a commercial licencse have hit the the World Trade Center and the Pentagon with a 767 or 757 at the sp

7) No 27.0% (53)

6) Probably not, it would be very hard to do 14.3% (28)

2) Yes, it would be fairly straightforward 12.2% (24)

8) No, the plane would be impossible to control at that speed 10.7% (21)

1) Yes 9.2% (18)

11) I don't know 8.7% (17)

9) No, the plane would have fallen apart at that speed 6.1% (12)

10) No, the plane could never even reach that speed. 4.6% (9)

4) Yes, but it would have been very difficult 4.1% (8)

3) Yes, but it would have needed a lot of concentration 2.0% (4)

5) Probably, but they were pretty lucky 1.0% (2)

Blank (View Results)(45)


Non-Blank Votes: 196
Content from External Source


POLL: Could pilots with a commercial licencse have hit the the World Trade Center and the Pentagon with a 767 or 757 at the sp

7) No 26.8% (62)

6) Probably not, it would be very hard to do 14.3% (33)

2) Yes, it would be fairly straightforward 10.8% (25)

11) I don't know 10.4% (24)

8) No, the plane would be impossible to control at that speed 10.0% (23)

1) Yes 9.1% (21)

9) No, the plane would have fallen apart at that speed 5.6% (13)

10) No, the plane could never even reach that speed. 5.2% (12)

4) Yes, but it would have been very difficult 3.9% (9)

3) Yes, but it would have needed a lot of concentration 2.6% (6)

5) Probably, but they were pretty lucky 1.3% (3)

Blank (View Results)(57)


Non-Blank Votes: 231
Content from External Source
 
Last edited by a moderator:
After considerable analysis . . . I have some thoughts . . .

1) There is no absolute proof that the aircraft supposedly involved in 911 collisions would have self-destructed at the speeds they appear to be flying prior to collision with the buildings . . .

2) They were all flying above the * DO NOT Exceed 250kts @ or Below 10,000ft Altitude.* specified by Boeing http://knology.net/~stirmac/POHfiles/767 POH.pdf

3) They were all flying below or just below "Never Exceed" in the case of the aircraft that hit WTC #1 . . . the (• Vne/Mne 516/0.86 Mach Never Exceed Speed)http://knology.net/~stirmac/POHfiles/767 POH.pdf

4) Why would you train for years and conspire to collide the buildings in your plan and take any risk of not hitting the Towers by flying so fast as to possibly lose control or have a wing fall off before you got to your target? Obviously, either the hijackers knew more about aircraft design and capabilities than many of the experts I have been reading or they were just plain stupid . . .

911 Speed Analysis.png
 
4) Why would you train for years and conspire to collide the buildings in your plan and take any risk of not hitting the Towers by flying so fast as to possibly lose control or have a wing fall off before you got to your target? Obviously, either the hijackers knew more about aircraft design and capabilities than many of the experts I have been reading or they were just plain stupid . . .

Well, the goal would be to hit the buildings at as high a speed as possible. If I were trying to do that I would accelerate as much as possible. If I started to lose control I would cut the power, and then I'd have control again. I suspect though that they never lost control, and in the last few seconds they did not need control as at that point collision was inevitable.
 
Well, the goal would be to hit the buildings at as high a speed as possible. If I were trying to do that I would accelerate as much as possible. If I started to lose control I would cut the power, and then I'd have control again. I suspect though that they never lost control, and in the last few seconds they did not need control as at that point collision was inevitable.
No . . . I totally disagree . . . the collision is way, way more important than the speed and they knew that . . .
 
Hey George,

I think TWCobra mentioned this before, but on point 2, that do not exceed 250 knots below 10,000 thing isn't really any kind of a structural speed limit set by the manufacturer. It's more of a legal speed limit, kind of like a sign on the side of the road. In general, civilian aircraft just are not supposed to cross 250 knots below 10,000, but most airliners generally can physically do it and still be within their normal operating range.
 
Hey George,

I think TWCobra mentioned this before, but on point 2, that do not exceed 250 knots below 10,000 thing isn't really any kind of a structural speed limit set by the manufacturer. It's more of a legal speed limit, kind of like a sign on the side of the road. In general, civilian aircraft just are not supposed to cross 250 knots below 10,000, but most airliners generally can physically do it and still be within their normal operating range.
I know that . . . it is just a published reference speed with altitude parameters . . . I think 650 Knots is where anyone has indicated possible airframe disintegration . . . where flight control may be affected is up for considerable debate . . . probably somewhere above "Never to Exceed Speed" I suppose above 520 Knots. . .
 
4) Why would you train for years and conspire to collide the buildings in your plan and take any risk of not hitting the Towers by flying so fast as to possibly lose control or have a wing fall off before you got to your target? Obviously, either the hijackers knew more about aircraft design and capabilities than many of the experts I have been reading or they were just plain stupid . . .

Keep in mind that the cited airspeeds are final airspeeds, the speeds at which they hit their towers. If the AA77 NTSB video was any indication, the hijackers did start out slow within the operating range of their respective aircraft until they got lined up. I suspect the hijackers probably didn't think too hard about the wings tearing off if at all though, but that's just my speculation. It's probable that if there were some signs of stress leading up to structural failure, the hijackers would feel something, perhaps a buffet or a noise, and in which case they may pull the power back. However, I think their final descents happened closed to less than 1 minute before impact and which hitting the target can be reasonably assured, so I doubt wings tearing off are that much on their minds. Again, speculation, but I think it's reasonable that their time spent in the overspeed condition was pretty short.
 
No . . . I totally disagree . . . the collision is way, way more important than the speed and they knew that . . .

Indeed, but high speed would also be a goal. You can accelerate without jeopardizing the mission. It's not like the plane would do a sudden backflip at a certain speed.

And I think it far more likely that some hijackers would recklessly push the plane past its design limits than some shadowy cabal would.
 
Keep in mind that the cited airspeeds are final airspeeds, the speeds at which they hit their towers. If the AA77 NTSB video was any indication, the hijackers did start out slow within the operating range of their respective aircraft until they got lined up. I suspect the hijackers probably didn't think too hard about the wings tearing off if at all though, but that's just my speculation. It's probable that if there were some signs of stress leading up to structural failure, the hijackers would feel something, perhaps a buffet or a noise, and in which case they may pull the power back. However, I think their final descents happened closed to less than 1 minute before impact and which hitting the target can be reasonably assured, so I doubt wings tearing off are that much on their minds. Again, speculation, but I think it's reasonable that their time spent in the overspeed condition was pretty short.
What advantage would one gain by increasing the airspeed from cruising speed to the final speed? So YOU think it was an emotional decision. . . logic would tell me to stick with the highest chance for success. . . .
 
Indeed, but high speed would also be a goal. You can accelerate without jeopardizing the mission. It's not like the plane would do a sudden backflip at a certain speed.

And I think it far more likely that some hijackers would recklessly push the plane past its design limits than some shadowy cabal would.
I disagree with your analysis. . . .if the aircraft were being remotely controlled for the last moments then increasing the air speed might be logical to maximize the destructive force. . . . if relying on humans only I would be most insistent on keeping the flight on target at all cost, ignoring the benefit of increased destruction which would probably never be seen above what is expected at cruising speeds anyway . . . the destruction either way would have been total . . .
 
If you want maximum destruction then high sped to maximise destruction is "desireable" whether under remote control or not. And remaining in control is also desireable for both.
 
I disagree with your analysis. . . .if the aircraft were being remotely controlled for the last moments then increasing the air speed might be logical to maximize the destructive force. . . . if relying on humans only I would be most insistent on keeping the flight on target at all cost, ignoring the benefit of increased destruction which would probably never be seen above what is expected at cruising speeds anyway . . . the destruction either way would have been total . . .

Well, so other than reckless hijackers, why would the plane be going so fast? What does this fast plane suggest to you?

Surely if it were being remotely piloted by experts, they would have kept the speed down to known manageable levels?
 
If you want maximum destruction then high sped to maximise destruction is "desireable" whether under remote control or not. And remaining in control is also desireable for both.
Nope. . . . if I am an evil cabal . . . I trust machines over people . . . I would not jeopardize the mission in either case . . . so full ramming speed is much more logical for the cabal than for some hijackers operating for OBL . . .
 
Well, so other than reckless hijackers, why would the plane be going so fast? What does this fast plane suggest to you?

Surely if it were being remotely piloted by experts, they would have kept the speed down to known manageable levels?

if I am an evil cabal . . . I trust machines over people . . . I would not jeopardize the mission in either case . . . so full ramming speed is much more logical for the cabal than for some hijackers operating for OBL . . .
 
Nope. . . . if I am an evil cabal . . . I trust machines over people . . . I would not jeopardize the mission in either case . . . so full ramming speed is much more logical for the cabal than for some hijackers operating for OBL . . .

But then you just said there's NO WAY hijackers would go to fast, so it seems like you trust them enough to do that :)

Really, is it more likely that some hijackers went a bit too fast, or that the entire thing was plotted by a secret government operation who used super-powerful remote control by computers to fly perfectly into the building.

Occam. There's no need to introduce these incredible new entities to the discussion when there's already a perfectly reasonable explanation.
 
I am an evil cabal . . .

I knew it!

Seriously, though, it does beg a question. The speeds were getting on for foot on the floor speeds - the only reason I can see for that would be to reach targets before interception by the military - but flying at those speeds, at those descents, with novices at the controls - that's got to be a big risk....
 
I knew it!

Seriously, though, it does beg a question. The speeds were getting on for foot on the floor speeds - the only reason I can see for that would be to reach targets before interception by the military - but flying at those speeds, at those descents, with novices at the controls - that's got to be a big risk....

The entire thing was a big risk.

I think they just lined it up, then floored it and prayed.
 
The entire thing was a big risk.

I think they just lined it up, then floored it and prayed.

But remember the Pentagon, where you said they weren't aiming to hit it where they hit it, but just to hit it (big target, all that?), yes?



Btw, you must be exhausted after all the thanks you've been getting! :p
 
But then you just said there's NO WAY hijackers would go to fast, so it seems like you trust them enough to do that :)

Really, is it more likely that some hijackers went a bit too fast, or that the entire thing was plotted by a secret government operation who used super-powerful remote control by computers to fly perfectly into the building.

Occam. There's no need to introduce these incredible new entities to the discussion when there's already a perfectly reasonable explanation.
Occam did not say refuse to consider rational possibilities or alternate explanations . . . Occam suggested the easiest solution should be given more consideration initially . . . I have done so and think the simplest explanation is an insufficient explanation because the success using it is astronomically improbable IMO . . . 3 for 3 is unprecedented under the circumstances and Occam may well have agreed with me!!!!
 
Occam did not say refuse to consider rational possibilities or alternate explanations . . . Occam suggested the easiest solution should be given more consideration initially . . . I have done so and think the simplest explanation is an insufficient explanation because the success using it is astronomically improbable IMO . . . 3 for 3 is unprecedented under the circumstances and Occam may well have agreed with me!!!!

Erm, 3 for 4.

Occam says do not multiple entities unnecessarily - don't pick the simplest explanation, but the one that makes the fewest assumptions. We have a simple explanation involving coordinated hijackings and flying planes into buildings. You've not really demonstrated that hijacking, or flying planes into buildings is particularly hard. But you still want to add on this new secret entity, and a whole complex sequence of actions to explain everything - making things vastly more complex - remote control planes, complicit federal agencies, maybe explosives?

What exactly is wrong with 3/4 of the planes hitting their targets? A bit of luck with the fire?
 
But remember the Pentagon, where you said they weren't aiming to hit it where they hit it, but just to hit it (big target, all that?), yes?

Well, that was "only" 460 knots. And Hanjour was the most experienced pilot.

http://en.wikipedia.org/wiki/American_Airlines_Flight_77#Crash
According to the 9/11 Commission Report, as Flight 77 was 5 miles (8.0 km) west-southwest of the Pentagon, it made a 330-degree turn. At the end of the turn, it was descending through 2,200 feet (670 m), pointed toward the Pentagon and downtown Washington. Hani Hanjour advanced the throttles to maximum power and dived toward the Pentagon. While level above the ground and seconds from the crash, the wings knocked over five street lampposts and the right wing struck a portable generator, creating a smoke trail seconds before smashing into the Pentagon.[34][35] Flight 77, flying at 530 mph (853 km/h, 237 m/s, or 460 knots) over the Navy Annex Building adjacent to Arlington National Cemetery,[36]crashed into the western side of the Pentagon in Arlington County, Virginia, just south of Washington, D.C., at 09:37:46
Content from External Source


Came pretty close to hitting the ground.
 
Conspiracies often remind me of the Ptolemaic explanation for the movements of the planets. And folks clinging to them when a simple explanation is offered are a lot like the Church and it's refusal to accept the new explanation. The reason is much the same, to admit that the planets orbited the Sun would shake a foundation belief.
 





3.5 minutes on 2 videos all about the best qualified hi-jacker, Hani Hanjour, from people who knew.

A 300 degree turn, Hanjour made - why fly five sixths of the way around the thing you want to hit before hitting it, if hitting it was all that was required? And not just 'flying round it', but performing some manouevre that would surely make him cry! Or was it required that The Navy Dept was hit? Not to mention that he flew past that nuclear power station on that river (why would any self-respecting terrorist miss that trick?!) - whatsitcalled - The Potomac....the one Robert McNamara prayed to every full moon on the banks of....
 
Came pretty close to hitting the ground.

The aircraft would have been in ground effect and it would have been surpringly difficult to hit the ground. The Canberra bomber was noted for the low passes. Only the crews knew that to get this low,

Canbera.jpg

...the pilot was holding FULL nose down on the stick. This may also be another reply to those who believe this was a great feat of flying. The hijacker may indeed have screwed up the attack, and the only thing that allowed him to hit the side of the building instead of plowing into the ground a few hundred metres short may have been ground effect.
 
why fly five sixths of the way around the thing you want to hit before hitting it, if hitting it was all that was required?

perhaps because they missed it the first time.

At 9:33 the plane crossed the Capitol Beltway and took aim on its military target. But the jet, flying at more than 400 mph, was too fast and too high when it neared the Pentagon at 9:35. The hijacker-pilots were then forced to execute a difficult high-speed descending turn.
Content from External Source
http://www.cbsnews.com/2100-201_162-310721.html
 





3.5 minutes on 2 videos all about the best qualified hi-jacker, Hani Hanjour, from people who knew.

A 300 degree turn, Hanjour made - why fly five sixths of the way around the thing you want to hit before hitting it, if hitting it was all that was required? And not just 'flying round it', but performing some manouevre that would surely make him cry! Or was it required that The Navy Dept was hit? Not to mention that he flew past that nuclear power station on that river (why would any self-respecting terrorist miss that trick?!) - whatsitcalled - The Potomac....the one Robert McNamara prayed to every full moon on the banks of....

Hmmmm . . . according to Mick he was their most experienced pilot I think . . . Old Occam may have to switch to our side Lee . . . LoL!!!
 
The aircraft would have been in ground effect and it would have been surpringly difficult to hit the ground. The Canberra bomber was noted for the low passes. Only the crews knew that to get this low,

Canbera.jpg

...the pilot was holding FULL nose down on the stick. This may also be another reply to those who believe this was a great feat of flying. The hijacker may indeed have screwed up the attack, and the only thing that allowed him to hit the side of the building instead of plowing into the ground a few hundred metres short may have been ground effect.
So now you are saying he had to hit the side of the Pentagon because he couldn't slam it into the ground???
 
What advantage would one gain by increasing the airspeed from cruising speed to the final speed? So YOU think it was an emotional decision. . . logic would tell me to stick with the highest chance for success. . . .

George, think about it.

The advantage: Maneuverability. Much more time to set up trajectory. Less load factor. Easier to point the plane to said target.

Emotion decision? When did I say that? It was most likely the last thing on their mind.

It's not a hard concept to grasp. Point the plane towards the target, then speed up. Newton's law does the rest.
 
3.5 minutes on 2 videos all about the best qualified hi-jacker, Hani Hanjour, from people who knew.

A 300 degree turn, Hanjour made - why fly five sixths of the way around the thing you want to hit before hitting it, if hitting it was all that was required? And not just 'flying round it', but performing some manouevre that would surely make him cry! Or was it required that The Navy Dept was hit? Not to mention that he flew past that nuclear power station on that river (why would any self-respecting terrorist miss that trick?!) - whatsitcalled - The Potomac....the one Robert McNamara prayed to every full moon on the banks of....

One says he was average to below average, the other says he was emotional and did not want to practice landings. Neither of them say that he could not of done it. Both instructors seem to assume he did.

I don't know, but the 300 degree turn was probably for altitude. If you are too high and close to something it makes sense to fly in a circle while descending. Or maybe he just did not have a visual. Check this video, the turn starts at around 1:08:50 and has leveled out by around 1:11:30, full throttle in a straight line for 45 seconds, then Pentagon impact at 1:12:15



That's real time, not quite the aerobatics people make it out to be.
 
perhaps because they missed it the first time.

At 9:33 the plane crossed the Capitol Beltway and took aim on its military target. But the jet, flying at more than 400 mph, was too fast and too high when it neared the Pentagon at 9:35. The hijacker-pilots were then forced to execute a difficult high-speed descending turn.
Content from External Source
http://www.cbsnews.com/2100-201_162-310721.html

Lol!!!! Where are you, so help me G!??????
 
George, think about it.

The advantage: Maneuverability. Much more time to set up trajectory. Less load factor. Easier to point the plane to said target.

Emotion decision? When did I say that? It was most likely the last thing on their mind.

It's not a hard concept to grasp. Point the plane towards the target, then speed up. Newton's law does the rest.
I know you think it was easy for these people to do what they allegedly did . . . but others don't and since we last talked I am no closer to accepting your take on the issue . . . I believe you believe what you are saying . . . however, I think these supposed pilots were worse than we thought . . . I still say let's have a demonstration . . . put a novice pilot in an advanced 757/767 simulator and try it out judged by a disinterested 3rd party . . . publish the results for all to evaluate . . .
 
I know you think it was easy for these people to do what they allegedly did . . . but others don't and since we last talked I am no closer to accepting your take on the issue . . . I believe you believe what you are saying . . . however, I think these supposed pilots were worse than we thought . . . I still say let's have a demonstration . . . put a novice pilot in an advanced 757/767 simulator and try it out judged by a disinterested 3rd party . . . publish the results for all to evaluate . . .

"Worst than we thought" how? Because members on your conspiracy website say so?

Here's a private pilot who landed an airliner in a simulator:
https://www.youtube.com/watch?v=htg0VKt3j_w

Landing an airplane tends to be more difficult than crashing one.
 
Here's what happened:



As they approached they had descended to 8,000 feet, however that then put them in a position too steep to descend from, so they did the descending turn. Then were lined up, back where they started the turn, but now at 2,200 feet, and went straight in. They pushed the nose down, and went straight in.

Rate of descent is controlled by two things - speed, and the aircraft attitude (if the nose is pointing up or down). Normally pilots descend by reducing power, and any pilot knows this automatically. But what he did here was go full power and push the stick forward. So long as you are going towards the target there's no need to reduce power. If you can't keep the nose down, then you'd reduce power.
 
Last edited:
That's what I said several posts ago George!!
Seems the issue there was could you even get it low enough at 430 knots to hit the Pentagon that low . . . I was assured by someone it was no problem . . . now this bomber can't hit the ground no matter how forward you push the yoke/ wheel . . . which is it . . . no can do . . . no sweat . . . but only exactly where 77 hit the Pentagon . . . make up your minds!!!!!
 
Last edited by a moderator:
A 300 degree turn, Hanjour made - why fly five sixths of the way around the thing you want to hit before hitting it, if hitting it was all that was required? And not just 'flying round it', but performing some manouevre that would surely make him cry! Or was it required that The Navy Dept was hit?

And to that last point - no, look at the track in Google Earth (attached), the point they hit was basically the point they were always aiming at, and that was dictated by the point at which they hijacked the aircraft. The only reason for the turn was to descend.

View attachment aa77v2.5.3.a.kmz
 
Back
Top