It’s obvious why I’m asking this, how much fuel does a 767 or similer sized plane typically carry. Since it was a Boston to LA flight I imagine it would be carrying the maximum fuel load. What would the equivilent explosive power be in pounds of TNT or whatever.
Or did the kinetic energy from the impact cause most of the damage?
A Boeing 767 carries about 24,000 gallons of fuel, which would be something like 160,000 pounds. That would be a big bomb, but fuel in that quantity wouldn’t explode in one big boom like a bomb would.
The reason the towers collapsed is probably because of the fire that followed the attacks - a fire fuelled by all that jet fuel. The thermal energy released by so much fuel would be incredible. Experts are already saying the fire would have melted the steel supports, causing the building to collapse at that point, and then the weight of the top section just takes the rest with it. The kinetic energy from the plane would not have been nearly enough to knock a skyscraper that massive down, since the main external structure would not have been much damaged by the impact.
A Boeing 757 carries 11,276 gallons, or about 79,000 pounds. (RickJay talks about a 767, which is different.)
http://www.boeing.com/commercial/767-200/product.html
lists 767-200 stats.
I made some estimates in this thread about the energy, both the kinetic energy and the energy of the fuel.
(Note: both planes were 767-200’s AFAIK, but I can’t verify this now–they were both 767’s, but might not have been 200’s.)
How come you want to know anyway? What are U planning. I am sure you could find out by checking out some websites. You ask too many questions that are very suspicious.
Senator J. McCarthy 
Something to remember is that liquid fuel burns, vapors explode…
want to test this? (at your own risk here) – drop a match into a container of gas – the match will go out.
Uh, try this with a gas can and you are likely to get serious burns at least. There is vapor in the top part. If what you say is true (and I am not necessarily confirming it, though it sounds right to me) then try it with a shotglass of gas. The small volume of gas in the shotglass will prevent really serious burning, and the short height won’t trap the vapors like a can will.
However, I wouldn’t try this at all. Not all science leads inevitably to experiment, at least on a personal scale.