Here is a link to a graphic of the flightpath of the a/c.
http://us.news2.yimg.com/f/42/31/7m/...s_graphic.html
It is being suggested now, that they overshot the White House and took the Pentagon as a secondary target. Anyone familiar with Washington will know that the White House is one of the harder landmarks to locate from the air, as it is relatively small compared to so many large structures surrounding it.
I think we may be very fortunate that two of these aircraft maybe did not hit their primary targets. If anything good might be salvaged from this horror, it is perhaps knowing that what has occurred might have been even worse. Unimaginable...