What was the mystery plane over wash dc? Here's a clip - youtube , then search "CNN on the 9-11 mystery plane" In one of the profile shots, the plane appears to be in a rapid descent. you can see how the file pic matches the plane esp a one of a kind hump behind this Mil version of a 747 called an E-4B - why is it over the DC area after all the US aircraft had been grounded? WH personnel are seen evac 1600 penn and SSvc people are pointing up to the white plane in obvious concern. This is a command and control aircraft with such extensive electronics and communications that ithas been called the "Doomsday plane".