theres a lot of different versions of this stuff but i think this says enough about the flight 93, the key seems to be the evidence of the debris field. and i don't listen to art bell.
There were numerous calls allegedly from Flight 93. Nearly all of these calls were supposedly made from cell phones, and were relatively short. The exception was the supposed call from passenger Todd Beamer on an Airphone, which was routed to Verizon supervisor Lisa Jefferson. Jefferson interviewd Beamer in detail in a conversation that would last from 9:45 until his famous last words before leading a passenger revolt: "Let's Roll". 3
Todd Beamer
The AP reported that at 9:58 a frantic passenger called from a bathroom and told operator Glenn Cramer that he had seen an explosion and smoke, and that the plane was "going down". 4 Investigators believe the passenger was Edward Felt.
Crash
At 10:06 AM, Flight 93 was apparently shot down near Somerset, Pennsylvania. The official story that it was flown into the ground as a result of a struggle to control the cockpit is contradicted by the reports of eyewitnesses on the ground, as well as the phone call attributed to Edward Felt.
The crash site comprised a central debris field and several smaller debris fields some distance away. One of the engines was found over half a mile away from the main field. 5 Other debris fields were found 2, 3, and 8 miles away. 6 This evidence is virtually impossible to reconcile with the official story.
http://911research.wtc7.net/planes/attack/flight93.html
other folks say the debris field was much smaller and don't mention
the engine but its still the best evidence(to prove or disprove)
left(available) that really shows the plane was shot down.