Well United Flight 93 was a terror event and it crashed in an open field. So anything is possible.
Flight 93 may have been destined for a major building in Washington, D.C, but the passengers rushed the cockpit or something - remember: ‘Let’s roll!’
Because they received cell calls from family informing them about the other 2 planes going into the WTC in New York, the (some) passengers made a brave decision that their plane was not going to crash into anything significant.