Boeing E-4

The Boeing E-4 Advanced Airborne Command Post (AACP), the current aircraft known as the "Nightwatch", [2] is a series of strategic military command and control aircraft operated by the United States Air Force (USAF). The E-4 series is specially modified from the Boeing 747-200B for the National Emergency Airborne Command Post (NEACP) program. [3] One of its main purposes is to ensure continuity of government during a nuclear war, which is why it is known as the "doomsday plane." [4]

The E-4 serves as a survivable mobile command post for the National Command Authority, i.e. the President of the United States, the Secretary of Defense, and their successors. The four E-4s are operated by the 1st Airborne Command and Control Squadron of the 595th Command and Control Group, located at Offutt Air Force Base, near Omaha, Nebraska. An E-4, when in action, is called the "National Airborne Operations Center" (NAOC).