Bill Sherwood

I'm not going to waste my time looking at Feltzer's links, but suffice to say they will be somewhere between quite silly and pure fantasy. There is the fact that the debris from the airliners was found on each of the crash sites, thousands of people saw the airliners do what they did, the airliners that were used are now missing (apart from being a pile of parts), and hundreds of missing passengers.

In this universe, however, diesel behaves pretty much the exact opposite to that. It is explosive (though hard to ignite) and burns quite hot.

Godwin's Law = you lose. But seriously .... I am reminded of the phrase, "you are entitled to your own opinions, but not your own facts".

It's not speculation, the airliner went through the middle of the building, end of story. You have, unfortunately, made up your mind that much is clear and hence it is pointless trying to convince you otherwise. You keep asking questions that have already been satisfactorily answered. You have no idea what my education level is, nor my experience, nor my interests, nor my hobbies, etc. Evan either. For example one of the things that you are quite incorrect about is that you seem to think Evan and I are Americans. I see from this you are not able to discuss the physics behind the tragedy and are going for the straw-man method. I will waste no more time on you.

Pt 2 Actually there's plenty of evidence. For example the plethora of videos showing the airliners impacting the buildings and a huge ball of flame erupting from the structure. Then the continued black smoke billowing from the towers until they collapsed. Again hundreds of videos very clearly show that is very much not the case. You'd need to show evidence of that, rather than just guessing. I don't waste too much time on it, I gave up trying to explain these things to people who have already made up their mind a long time ago. Because of that I'm not going to spend too much more time here, unless you are genuinely interested in what went on.

It is common sense, fortunately. Neither impact was a glancing blow, both aeroplanes hit the sides of the towers close to the centre and the damage they caused caused the central core to effectively be cut in half. That core was a very important structural member and without it there was not much to support the internal floors. The skin of the towers also bore a fair bit of the vertical and torsional loads of the structure, and again there was massive damage to that structure and the aeroplane entered one side and the debris exited the other side like a shotgun blast. The reason the second tower came down first is also very easy to explain and understand; the impact was further down, the aeroplane hit when banked over and so damaged more floors than the first plane, and (I think) was travelling faster. All those reasons mean more damage and the greater mass of building above the damaged section pressing down on it harder caused an earlier failure. Pretty simple really. Correct in that there have been no other large building like that, that have had airliners flown into them at high speed deliberately. The logic, as explained above, is pretty obvious; massive structural damage from an impact that was like a very large bomb going off. The towers were nearly cut in half so again I have to say it's a bit surprising they did not come down far earlier. From the hundreds of videos widely available, it is clear that neither impact was a glancing blow. That is simply totally wrong.

Building 7 was very badly damaged by the collapse of the two main trade towers, hence it collapsing later on. You typically cannot see the damage to it on the conspiracy sites as they tend to not show photos of it, as it undermines their opinions. There is physically no problem at all with the way the two trade towers collapsed, they went down pretty much exactly as you would expect after sustaining such massive damage. (I have to again say that after such an impact I an very surprised they didn't come down immediately) Then there is the problem that there is precisely zero physical evidence found of any explosives that were supposed to have brought the towers down. The conspiracy sites would try to have you believe that there is such things as 'nano-thermite' but no such material exists. What I suspect was found was the component of thermite, which is basically rust from steel. Steel, when heated to high temperatures, will also sometimes flake off sections that will turn rusty very quickly. Scaling I think it's called. So, with the debris in the footprint of the towers it is not at all surprising to find what would appear to be traces of what could have been thermite, but in reality is just heat-damaged steel beams. The free-fall thing is also incorrect as if you look at different videos you can see from videos from different angles there may be some small periods where the upper tower sections are briefly falling at near free-fall speeds but the dust cloud quickly obscures the last part of the fall, where the upper section slows down dramatically. If you take the time to look at the science behind it all, there really is no mystery as to why the buildings behaved the way they did and certainly no need to invoke the conspiracy theory.

PFT are indeed, a bunch that make up certain fictions to suit themselves. I have caught them making alternate realities many times in the past. Now while they are quite unreliable as such, the data they show should be examined for errors. The possibility of any of the airliners still flying after they crashed is of course zero, so there must be some kind of error in the times reported.

Sort-of on topic, here's a list of some of the things that have gone wrong with manned missions. "One third of manned spaceflights suffer major problems that threaten completion of the mission and the life of the astronauts. Five crews - 2% of missions - have perished in their spacecraft....SPACEFLIGHT IS NOT 'ROUTINE'." http://www.astronautix.com/articles/thespace.htm

A quick PMSL moment from my car forum, where this 9/11 nonsense is being talked about. There were no people rescued from the rooftops of the tower, mainly because the access doors were locked. I said that I'd get through them any way I could, fire axe, etc. Someone simply replied, "They could have used some of the explosives used to do the controlled demolition to open the doors....." Ha!

Thanks!

Just a FWIW, here's a truck in Australia that was left behind when the big fires went through Victoria a couple of years ago. What you are looking at is the remains of all the aluminium parts in the truck after they have melted from the heat of the fires - The fires were just grass and other organic combustibles, yet it was hot enough and for long enough to melt substantial chunks of metal. Just making a point that whilst seemingly simple things like having 'X' amount of combustible material (grass, kerosene, etc) may only seem to allow for a certain amount of heat to be passed on, it can sometimes be deceiving and here is proof that it can sometimes be far greater than what you would expect. I've also seen a photo of melted steel from those grass fires, but I cannot find it again sorry. Edit - might be a good idea to add the photo Bill!! Hey it was getting very late & cold and I only remembered after I was tucked-up in a nice warm bed, it had to wait until morning.

No.

I'm not going to go through the usual mass of poor information here, but only show the inaccuracies of the first paragraph as an example. The stick shaker does no, in fact, have anything at all do do with high-speed flight. It is actually for the exact opposite - when you are flying too slowly and the aeroplane is about to stall. The thing about the engines not being able to suck enough air is also quite wrong. Anyway, keep up the good work for discrediting the truthers, Jim, you're doing a great job of presenting easily dis-proven stuff.

Kerosene - quite similar to diesel - is pretty hard to ignite. For example if you pour a litre or two on the ground and throw a lit match into it, it probably won't ignite. And in any case to get ignition you need substantial vapour and not liquid, hence the delay from when the fuel tank starts to come apart and ignition. At the speed the plane was travelling at that could be up to tens of metres. Yet again I can confirm that the speed they were doing is not impossible at all and is not particularly difficult to do if you ignore the overspeed audible warnings and wind noise.

Perfect, thanks That looks exactly how you'd expect it enter the building of that type of construction - the outer shell is relatively soft, unlike the Pentagon, so very little aircraft would get blown-back from the impact point and virtually all of it keep pushing into the building. The fuel, as I have mentioned a number of times, has quite a lot of mess and so as a soft mass would keep moving forwards at quite high speed as it started to ignite and burn. The really heavy stuff in the plane (engines, etc) would hardly be slowed by anything and as the plane looks like it impacts in fairly level flight then things like desks, people, thin walls and so-on will not provide any real impediment to the motion of a five or six tonne engine that's also still making a bit of thrust.

Is there a clear video handy of that please? I had a quick look on Youtube and got all sorts of stuff that didn't seem quite right.

http://vimeo.com/13704095 It's Phil Plait making a heck of a lot of sense.

It's somewhat more difficult to go supersonic than it is to fly at a high sub-sonic speed, no matter the altitude. Again - and hopefully for the last time - high speed at low levels simply is not a problem at all. It's even easier than up high as you have so much more power. Quick example - When I got type rated on the Cessna Citation 2 jet, because the pressurisation wasn't working properly we were stuck down at 10,000'. The training Captain was showing me how well it performed at that height, even on one engine. We were talking about something for a minute or so, and he'd left one engine idling with the other at full power, then after a minute or so the overspeed beeper started. Another friend of mine told me of the time during training when his training Captain did a similar trick, but on takeoff; he slowly pushed up one throttle to full power and made an otherwise normal takeoff but only on one engine. So having enough power to fly at very high speeds down low is simply not a problem at all. If you really want to go faster then you dive down a little and by doing that you can easily pick up another 50 knots. I hope this is the last time you bring this up, it is completely dis-proven.

They have been thoroughly and repeatedly dis-proven. No need to go over it again and again, it's a waste of time.

Got anything new, James? Every one of those has been utterly dis-proven many times.

Each of those carries different scales as such - - Yes a 747 can carry a lot more than a 757 and it's because it's quite a lot larger. It has far greater internal volume so you can stick more freight in and also freight of larger dimensions. - The engines on both types are quite similar, though there's four on the 747 of course and they also typically make a bit more power. - The dimensions and mass of all types are pretty easy to find through Wikipedia or the Boeing site.

Not significantly, they are all pretty much built the same. Just the scale of the machine is quite different from a 757 to a 747 - a 747 can carry the weight of a 757 in fuel alone. Ta, EB, 360kts is Vno, much like my guess just before.

As I've mentioned and demonstrated several times here, structural integrity is just not a problem when going fast. It can be if you want to do aerobatics, but not if you aren't pulling more than a couple of G's. Two G's is two G's at either 200 kts or 500 kts, it makes no difference. I'm not rated on the 757/767 but I'm sure the maximum allowed airspeed is going to be in the upper 300 knot range - I'd estimate a good 360 kt to 370kts would be reasonable. For example at sea level the 747 red-lines at 381 knots, and indeed down low there's more than enough power to climb away at that speed. As the power decreases with altitude though you have to bring the speed back to keep it climbing. In any case, it's a bit like driving a car on the highway. The speed limit is 100 km/h and that's about as fast as you normally go. But the car could easily do 150 km/h and the car and occupants would be just fine. Yes it's just an analogy but it's still valid.

Sure - http://www.dc-8jet.com/0-dc8-sst-flight.htm The rudder trim-tab got a bit of a buzz happening and they unsurprisingly had to use elevator trim to recover from the dive but the aeroplane was otherwise easy to fly and undamaged. Very high speeds simply aren't a problem.