The E-4B “Nightwatch” may look like Air Force One, but they are the United States National Airborne Operations Center for use in times of emergency. As they would likely be used in the event of a nuclear strike on the United States or something else of that nature, they have been nicknamed the “Doomsday Plane.” However, these impressive examples of American power were first introduced in 1974 and are now getting long in the tooth. It has just been announced that Sierra Nevada Corp. has out-competed defense contractor giant Boeing to build the replacement.