73-1677 Boeing E-4B Advanced Airborne Command Post (747-200B) (MSN 20683/204) of US Air Force 1st Airborne Command Control Squadron (1st ACCS), 55th Wing, Offutt Air Force Base, Nebraska, USA, at Perth Airport – Tue 13 Nov 2012. Pushing back from bay 156 for engine start at 7:46am using callsign ‘GRIM 42’, with US Secretary of Defense Leon Panetta aboard after the annual Australia-United States Ministerial (AUSMIN) talks, focused on increasing US Marine presence in Australia; improved US Air Force access to northern Australia bases, and a significant increase in US warships using the HMAS Stirling naval base south of Perth. This aircraft was built as an E-4A, and first flew in September 1973, and was converted to an E-4B in the early 1980s, with the addition of a large satellite antenna hump behind the upper deck. It is designed as a survivable platform to conduct war operations in the event of a nuclear attack – the media nicknamed the E-4 as “the doomsday planes”. The aircraft were originally based at Andrews Air Force Base, Maryland, so that the U.S. President and Secretary of Defense could access them quickly in the event of an emergency. Later, they were based at Offutt Air Force Base where they would be safer from attack. Until 1994, one E-4B was stationed at Andrews Air Force Base at all times so the President could easily board it in times of world crisis. One E-4B is kept “on alert” at all times, manned 24 hours a day with a watch crew on board guarding all communications systems, awaiting a launch order. The E-4B is designed to survive an Electro-Magnetic Pulse (such as that caused by a nuclear bomb) with systems intact, and uses analog instruments because they are less susceptible to an EMP. The aircraft has state-of-the-art direct fire countermeasures. Operates with a crew of 48 to 112 people, the largest crew of any aircraft in US Air Force history. With in-flight refueling, it is capable of remaining airborne for lengthy periods, limited only by consumption of the engines’ lubricants and crew requirements). In one test, it remained airborne for 35.4 hours. Photo © David Eyre.