The United States Air Force operates a fleet of four Boeing E-4B aircraft, known as 'Doomsday Planes', designed to function as airborne command centers during nuclear attacks or other extreme emergencies. These aircraft can fly continuously for seven days and are equipped to maintain national command and control if ground-based systems are destroyed. The E-4B serves as a secure operations hub for the US President, Defense Secretary, and Joint Chiefs of Staff during crises.

To modernize its capabilities, the Air Force is converting five Boeing 747–8 aircraft, previously used by Korean Air, into replacements for the E-4B fleet. The upgrades include radiation and electromagnetic pulse protection, advanced communication antennas, mission systems, and in-flight refueling capability. The total cost of the five aircraft is estimated at 13 billion US dollars.

The E-4B’s unique features include 67 antennas for global communication, missile-launch capability, and protection against nuclear, cyber, and electromagnetic threats. The aircraft can take off within minutes of an emergency and remains on standby 24 hours a day, ensuring uninterrupted command continuity for the United States.