Interesting -- I looked on the UA website and on the Dulles airport flight info websites and couldn't find his flight number. I suppose they could have changed the schedule between August 11 & now. I did find UA 3429. Given the four-digit number, I suspected it was a cropduster and, likely, a commuter airline. I was right, if this other flight # is correct. The flight was actually Trans States Airlines. That doesn't relieve UA of any responsibility and future liability, but, it does perhaps explain why the crew was so weird about this. Not being UA, they can't really claim 9/11 paranoia as a reason.