The huge capacity of the Boeing 747 made it an ideal airframe for the Advanced Airborne Command Post (E-4). In 1973, the E-4 took over the mission of the EC-135 flying command post aircraft: to provide safe airborne headquarters for military and civilian leaders, including the president, secretary of Defense, and Joint Chiefs of Staff in times of emergency.
The original three E-4As were upgraded to the standard of the E-4B. The first B model was delivered Dec. 21, 1979, and entered service in January 1980. By 1985, all aircraft were converted to B models.
The four E-4s carry 13 external communications systems and are designed for missions lasting 72 hours. Their "hardness" features protect the crew from electromagnetic radiation and the effects of a nuclear blast.
Secondary missions assigned to the E-4B include VIP travel support and Federal Emergency Management Agency support, which provides communications to relief efforts following natural disasters such as hurricanes and earthquakes.
All E-4Bs are assigned to the 595th Command and Control Group at Offutt Air Force Base, Nebraska.
|First flight||June 19, 1973|
|Classification||Advanced Airborne Command Post|
|Span||195 feet 8 inches|
|Length||231 feet 4 inches|
|Gross weight||800,000 pounds|
|Top speed||More than 600 mph at 30,000 feet|
|Endurance||More than 12 hours|
|Ceiling||45,000 feet plus|
|Power||Four 52,000-pound-thrust F103-GE-100 turbofan engines|
|Accommodation||Up to 94 personnel, including flightcrew and 30 battle staff members|