In 1973, the Air Force acquired 747-200 aircraft under the code name “Nightwatch” to serve as part of a larger network of aircraft performing the “Worldwide Airborne Command Posts” mission. It would become one of the most complex airborne systems to ever fly.
The initial aircraft were given the military designation of E-4A and an additional aircraft was delivered in 1979 with system enhancements installed by L3Harris that was designated the E-4B. The rest of the fleet was upgraded to the E-4B configuration. Now in 2022, the platforms headquartered at Offutt Air Force base celebrate almost five decades of mission service in the U.S. Air Force (USAF) fleet.
According to the USAF , the E-4B serves as the National Airborne Operations Center and is a key component of the National Military Command System for the President, the Secretary of Defense and the Joint Chiefs of Staff. In case of national emergency or destruction of ground command and control centers, the aircraft provides a highly survivable command, control and communications center to direct U.S. forces, execute emergency war orders and coordinate actions by civil authorities. Operations encompasses all phases of the threat spectrum.
With roots of its mission in the first-generation C-135A jets, the E-4B provided state-of-the-art communications systems to serve as airborne command posts in the event of nuclear war. The larger aircraft accommodated more sophisticated communications systems as well as providing room for additional staff.
The Air Force describes the E-4B as a four-engine, long-range high-altitude aircraft capable of refueling in flight. The main deck features six functional areas and may include seating for up to 112 people, such as a joint-service operations team, USAF flight crew, maintenance, security and communications team.
The E-4B aircraft is protected against the effects of electromagnetic pulse and is designed to support advanced electronics and a wide array of communications equipment. Advanced satellite communications provide worldwide communications connectivity for senior leaders.
When not performing its military missions, the E-4B provides support to the Federal Emergency Management Agency, which provides communications and command center capability to relief efforts following natural disasters, such as hurricanes and earthquakes.
While its mission has evolved over the decades, one thing that remains unchanged is that E-4B aircraft and crews remain on standby 24/7 in preparation for national emergencies.