Shanksville to waynesboro is 102 miles by car
Site R near Waynesboro is the P-40 prohibited area on the Washington FAA VFR sectional
Flight 93 was shot down near sommerset which is on the Detroit
FAA VFR sectional
boeing 757-200 cruising speed is 460 kts
Flight time from Sommerset to P-40 would be 10-20 minutes
(just an eyeball guesstimate without actually plotting
distances and flight times.) The shoot down must have been
based on flight path and failure to respond to radio calls
rather than actual airspace incursion
Flight 93 was not operating in a prohibited area,
a restricted area, or a military operations area at the
time it crashed. Flight 93 may have violated Pittsburg Terminal Control Area airpace. The actual flightpath would need to be plotted to determine this. Busting a TCA usually will not get you shot down
though it might get you an F-16 or a Blackhawk escort. Flight 93 turned its mode C transponder off at
9:40 AM. This would also warrant special attention as radar contact is then lost. Air traffic control must
then rely on primary radar returns for tracking.
I was a pilot for ten years, and a flight instructor for five years
with over seven hundred hours of flight time in my log book.
You may view the appropriate sectionals here
http://skyvector.com/