Aus 9/11 Wiki
Congressional staff attorney Fred Hey was driving by on Route 50 at that moment. "I can't believe it! This plane is going down into the Pentagon!" he shouted into his cellphone. On the other end of the line was his boss, Rep. Bob Ney ® of Ohio. Representative Ney immediately phoned the news to House Sergeant-At-Arms Bill Livingood, who ordered an immediate evacuation of the Capitol itself. http://www.csmonitor.com/2001/0917/p1s1-usgn.html
Here's Route 50:
He had no view of the Pentagon. Not a witness to the alleged impact.
Source List: SGYDK