salo_t, I didn’t know other aspects about the Pentagon crash. You mean they didn’t discover bodies of the passengers who were supposed to be on that airplane?
For those who’re interested in this matter in a serious way, here is the official version — read the FAQs, http://wtc.nist.gov/
Rationally, I believe that the WTC implosion (collapse is not the right words, ’cause the buildings didn’t simply collapse, they imploded) can’t be caused 100% by the planes. Emotionally, I don’t know where I am — this is just too hard to believe.