US's 'doomsday planes' to get modern upgrades

During the Cold War, there was a prevalent expectation of the risk of a global nuclear conflict, during which both sides—NATO and the Warsaw Pact—would make extensive use of nuclear weapons. It was assumed that other nuclear-armed nations might also join the exchange. Thus, it was acknowledged that the risk existed, if not of the complete destruction of life on Earth, then at least of the elimination of human civilisation as we know it, significantly complicating life on Earth for at least several generations.

Because of this, numerous attempts were made, particularly in the USA and the USSR, to secure at least part of the state's potential for whatever future might come. One element of the "survival system" was the so-called doomsday planes or doomsday aircraft.

"Doomsday planes" were designed to serve as airborne command centres. By taking to the air after the detection of ballistic missile launches by the enemy, they would provide relative safety to the crew. This would be further aided by mechanisms such as increased resistance to electromagnetic pulses (e.g., generated during a nuclear explosion), protection against cyberattacks (in newer versions), the use of analogue navigation instruments, etc.

In the USSR, the Ilyushin Il-80 was developed, to be replaced by the delayed Ilyushin Il-96-400M programme. In the USA, these functions were first fulfilled by the EC-135J and today by the E-4 Advanced Airborne Command Post in version B. In the USA, this aircraft serves to transport and ensure the safety and capability of the National Command Authority to perform their duties, explicitly highlighting the President (as the Commander-in-Chief of the US Armed Forces), the Secretary of Defense, the Chairman of the Joint Chiefs of Staff, and several key officials since 2002. These machines always accompany the US President's travels aboard Air Force One.

Alongside the airborne command centres, among the "doomsday" planes, other aircraft are also identified such as the E-6B Mercury (an airborne command and communications post developed to support the command of strategic forces), E-3 Sentry early warning and control aircraft, E-8 Joint STARS (a battle management, ground surveillance, and USAF command support aircraft), and the RC-135 Rivet Joint (an electronic reconnaissance aircraft).

Today, some of these aircraft's tasks are performed by unmanned RQ-4 Global Hawk. Of course, besides the aircraft carrying out key tasks, which must remain airborne for extremely long periods (often for several days without interruption), the "last airborne fleet of the USA" would also require numerous support machines like aerial refuelers (e.g., KC-135 or KC-46).

Currently, a key function in the USAF, and to some extent in the entire "strategic resilience system of the USA", belongs to the E-4B Nightwatch aircraft. Only four such aircraft were produced, three in the basic version and one in version B, and over time, they were standardised. All belong to the 1st Airborne Command and Control Squadron from the 595th Command and Control Group, stationed at Offutt Air Force Base in Omaha, Nebraska.

The E-4A was built in the 1970s based on the Boeing 747-200 passenger aircraft. The first and second were delivered in 1973, and the last in October 1974. Interestingly, the third model was powered by GE F103 engines (instead of Pratt & Whitney JT9D), which eventually replaced the propulsion of the first machines. By the end of 1979, the first E-4B was delivered, and the older planes were upgraded to the new standard by January 1985. The programme cost was estimated at £435 million (about £3 billion in 2023). In the middle of the first decade of the century, the aircraft underwent a modernisation costing £1.6 billion. The operating cost of the small E-4B fleet also runs into hundreds of millions of pounds annually.

Aircraft built on the basis of the famous Jumbo Jets can accommodate up to 112 people, including the crew, mission personnel, and key passengers. The original civilian aircraft were heavily rebuilt, adding, among other things, an in-flight refuelling installation—during one fuel delivery test, it enabled an uninterrupted flight for over 35 hours, but in theory, the plane can stay airborne for a week.

The aircraft has three decks. The upper deck houses the flight crew and additional navigation equipment. The middle deck contains (from the front): a galley, a VIP suite, a conference room with a nine-person table, a service room and briefing room, an operations team room (with workstations for 29 people), a communications room (six stations), and a rest area. The lower deck holds water tanks, battery accumulators, VLF and SHF SATCOM transmitters, an 8 km spool-wound TWA antenna for communication with underwater ballistic missile carriers, and other equipment. One such machine is always maintained in a state of readiness, ready to take off at a moment's notice.

As mentioned above, the E-4B planes are old, produced at best in 1979. As early as 2006, there was a proposal to retire them from service, but more pressing needs have consistently been recorded since then. The programme to build a successor—the E-4C Survivable Airborne Operations Center—only began in 2019. Currently, it is assumed that the E-4B will serve until 2039.

The Pentagon commissioned Sierra Nevada Corporation to develop the new "doomsday plane." The company received a contract worth £10.4 billion and the first tranche of funds amounting to £39 million. This stage of the programme will last until July 2036, during which time the manufacturer must develop a new machine and deliver both a prototype and the first production aircraft. Ultimately, the US Air Force is to receive eight such machines. The base platform will similarly be a Jumbo Jet, though a modern version of the 747-8. These will be used machines, as the production of the legendary passenger plane has already ended. Specific airplane units for conversion have already been selected.

The specific requirements for such a crucial machine are, of course, undisclosed. It is known that it should provide the three key American wartime leaders with safe and comfortable working conditions. Modifications towards increased resistance to electromagnetic pulses can be expected, possibly including the installation of an active defence system. As a centre for command, control, and communication with the US Armed Forces, it will certainly be equipped with various communication systems, including those necessary to manage the nuclear arsenal.

Before a used Boeing 747-8 becomes the E-4C, it will likely be dismantled and reassembled. It may take to the skies for the first time in a few years. Over the subsequent years, its interior will become one of America's most closely guarded military secrets (materials from the interior of the E-4B have only recently been revealed). It will likely participate in numerous training flights, as well as simulated alarms. It's preferable for everyone if the crew never has to launch the E-4C for its intended purpose.