Boeing E-4
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| E-4 "Nightwatch" | |
|---|---|
 E-4B in flight |
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| Type | Airborne Command Post |
| Manufacturer | Boeing |
| Introduced | 1974 |
| Retired | planned for 2012 |
| Status | In Service |
| Primary user | United States Air Force |
| Number built | 4 |
| Unit cost | US$223 million (1998 dollars)[1] |
| Developed from | Boeing 747 |
| Variants | Boeing VC-25 |
The Boeing E-4 Advanced Airborne Command Post, with a project name of "Nightwatch", is an aircraft operated by the United States Air Force and is specially built to serve as a survivable mobile command post for the National Command Authority, including the President of the United States, the Secretary of Defense, and successors.
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[edit] Development
Two of the original 747-200 airframes were originally planned to be commercial airliners. When the airline did not complete the order, Boeing offered the airframes to the USAF as part of a package leading to a replacement aircraft for the then used NEACP EC-135J model. The first E-4A was completed at the Boeing plant outside Seattle, Washington in 1974. The "A" model effectively housed the same equipment as the EC-135, but offered more space and an ability to remain aloft longer than an EC-135. Additionally the E-4 was capable of operating the "Looking Glass" mission of the Strategic Air Command (SAC).
The E-4A aircraft were capable of remotely launching retaliatory strikes from SAC missile fields. (In time SAC relinquished the aircraft to full time use by the OJCS.) Two more E-4As were built by Boeing. In 1979 Boeing built the first E-4B, which was distinguished from the earlier version by the presence of a large "hump" on the dorsal surface directly behind the upper deck. This contains the aircraft's SHF satellite antenna. By 1980 all three E-4As had been retrofitted to E-4B models. The E-4B offered a vast increase in communications capability over the previous model and was considered to be 'hardened' against the effects of electromagnetic pulse (EMP) from a nuclear blast. Hardening the aircraft meant that all equipment on board was shielded from EMP. Additional steps were taken to block radiation from the aircraft's cabin air management system.
Estimates at the time of the production of the first E-4B placed the developmental cost at nearly US$ 1 billion. The roll out cost of the fleet was placed at approximately US$250 million each. The E-4B is capable of operating with a crew of 60 to 114 people, the largest crew of any aircraft in US Air Force history.
[edit] Design
The E-4B is designed to survive an electromagnetic pulse (EMP) with systems intact, and has state-of-the-art direct fire countermeasures. With in-flight refueling it is capable of remaining airborne for a considerable period (limited only by consumption of the engines' lubricants). In a test flight for endurance, the aircraft remained airborne and fully operational for 33 hours. It takes two fully loaded KC-135 tankers to fully refuel an E-4B.
The E-4B has three operational decks; Upper, middle and lower.
[edit] Upper Deck
- The Flight Deck
The flight deck contains the pilot's, copilot's, navigator's and flight engineer's stations. A lounge area and sleeping quarters for flight crews and other personnel are located aft of the flight deck.
[edit] Middle Deck
The middle deck contains the conference room, which provides a secure area for conferences and briefings. It contains a conference table for nine people. Aft of the conference room is a projection room serving the conference room and the briefing room. The projection room has the capability of projecting computer graphics, overhead transparencies or 35mm slides to either the conference room or the briefing room either singularly or simultaneously.
- Operations Team Area
Behind the projection room is the operations team area containing the automatic data processing equipment and seats and console work areas for 29 staff members. The consoles are configured to provide access to or from the automated data processing, automatic switchboard, direct access telephone and radio circuits, direct ("hot") lines, monitor panel for switchboard lines, staff and operator inter-phone and audio recorder.
- Technical Control Area
The aft compartment at the end of the main deck is the Technical Control (Tech Control) area. This area was the nerve center for all communications and communications technicians. Typically 3 of the 6 crew positions were occupied here by specialized US Air Force Technicians that were responsible for the proper monitoring and distribution of all communications power, cooling, and reliability. The Technical Controller #1 (Tech 1, TC1) was the direct interface with the aircraft Flight Engineer and Flight Crew. This position was also the main focal point for all communications related issues. The Technical Controller #2 (Tech 2, TC2) was responsible for maintaining all UHF communications between the aircraft and the Nightwatch GEP (Ground Entry Points). These GEP's provided 12 voice lines to the aircraft which were used in the day to day operations of the mission. Secure Voice was also provided. The SHF Operator (actually a technician) maintained the SHF satellite link and provided other worldwide communications services probably having replaced a lot of the UHF capabilities.
- Rest Area
The rest area, which occupies the remaining portion of the aft main deck, provides a rest and sleeping area for the crew members.
- Forward Entry Area
Within the forward entry area is the main galley unit and stairways to the flight deck and to the forward lower equipment area. This area contains refrigerators, freezers, a convection oven and a microwave oven to give stewards the capability to provide more than 100 hot meals during prolonged missions. Additionally, four seats are located on the left side of the forward entry area for the security guards and the stewards.
- NCA Area
Behind the forward entry area is the NCA area, which is designed and furnished as an executive suite. It contains an office, a lounge and sleeping area, and a dressing room. Telephone instruments in this area provide the NCA with secure and clear worldwide communications.
- Briefing Room
The briefing room contains a briefing table with three executive seats, eighteen additional seats, a lectern and two rear projection screens.
- Communications Control Area
The communications control area is divided into a voice area and a data area. The voice area, located on the right side of the compartment, contains the radio operator's console, the semi-automatic switchboard console and the communication officer's console. The data area, located on the left side of the area, contains the record communications console, record data supervisor's console, high speed DATA/AUTODIN/AFSAT console and LF/VLF control heads.
- Flight Avionics Area
The flight avionics area contains the aircraft systems power panels, flight avionics equipment, liquid oxygen converters and stowage for baggage and spare parts.
[edit] Lower Deck
The forward lower equipment room contains the aircraft's water supply tanks, 1200 kVA electrical power panels, step down transformers, VLF transmitter and SHF SATCOM equipment. Electrically operated retractable stairs, located in the forward right side of the forward lower equipment area, are installed for airplane entry and exit.
The aft lower equipment area contains the maintenance console and mission specific equipment.
The lower trailing wire antenna area contains the aircraft's 5 mile long trailing wire antenna reel, the antenna operator's station as well as the antenna reel controls and indicators.
[edit] Operational history
The E-4 fleet was originally deployed in 1974,[1] when it was termed National Emergency Airborne Command Post or NEACP (often pronounced "kneecap"). The aircraft originally served as a survivable mobile command post for the National Command Authorities (the President of the United States and the Secretary of Defense, and successors). Other support staff would board the aircraft such as members of the Joint Chiefs of Staff. The aircraft was to provide a survivable platform to conduct war operations in the event of a nuclear attack. Early in the operations of the E-4, the media dubbed the aircraft as "the doomsday planes".
Originally stationed at Andrews Air Force Base in Maryland, so that the U.S. President and Secretary of Defense could access it quickly in the event of an emergency. The origin of the name "Nightwatch" comes from the richly detailed Rembrandt painting of the same name depicting local townsfolk protecting a town and was selected by the Squadron's first commanding officer. Later, the aircraft were moved to 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.
Two US Presidents have flown on the E-4, President Jimmy Carter and President Ronald Reagan.[citation needed] When a President boards the E-4, its callsign becomes "Air Force One". The E-4B also serves as the Secretary of Defense' preferred means of transportation when traveling outside the United States.[2] The spacious interior and sophisticated communications capability provided by the aircraft allow the Secretary's senior staff to work for the duration of the mission. Approximately 40 crew members are required to operate, maintain and guard the aircraft whenever he uses it.[citation needed]
The first E-4B was delivered to the Air Force in January 1980. All E-4s were converted to B-models by 1985.[1] With the adoption of two highly-modified Boeing 747-200Bs (known as VC-25A in Air Force parlance) to serve as Air Force One in 1989, and the end of the Cold War, the need for NEACP diminished. In 1994, NEACP began to be known as NAOC, and it took on a new responsibility: ferrying Federal Emergency Management Agency crews to natural disaster sites and serving as a temporary command post on the ground until facilities could be built on site.
The "cocked" or "on alert" E-4B is manned 24 hours a day with a watch crew on board guarding all communications systems awaiting a launch order (klaxon launch). Those crew members not on watch would be located in the alert barracks, gymnasium, or at other base facilities. Given the nature of the mission, tests were often carried out where the crew would respond to the aircraft triggered by the sound of a loud klaxon. These tests often happened during nighttime hours, when directed by a higher authority, or when certain communications links failed. From time to time, special mission practice events occurred. There were two prominent special missions code-named "OPAL" and "JEEP". OPAL was a simulated arrival of the President brought to the E-4B location by Marine One, a helicopter operated by Marine Helicopter Squadron 1 (HMX-1). Occasionally this might include a no-notice launch and exercise with a surrogate President. JEEP exercises would be similar but the intent was to test an evacuation of high ranking government officials, including the Defense Secretary or Presidential successors. The 24 hour alert status at Andrews AFB ended when President Clinton ordered the aircraft to remain at Offutt unless needed, though relief crews remain based at Andrews, and Wright-Patterson Air Force Base. One E-4B is kept on full alert at all times.[citation needed]
As the Soviet nuclear threat diminished in the 1990s, the aircraft mission was modified to support the Federal Emergency Management Agency (FEMA) and renamed NAOC (the National Airborne Operations Center). Previous NEACP aircraft used the static callsign "Silver Dollar"; this callsign faded from use when daily callsigns were put in use.
On September 11, 2001, an aircraft closely resembling an E-4B was spotted orbiting the Washington D.C. area by news outlets and citizens, during the attack on the Pentagon. This aircraft sighting has added fuel to the continued speculation and debate concerning the 9-11 attacks.[1]
In January 2006, Secretary of Defense Donald Rumsfeld announced the entire E-4B fleet would be retired starting in 2009. However the current Secretary reversed this decision in May 2007. The E-4B fleet will remain in service until at least 2015.[citation needed]
Four are currently operated by the United States Air Force, and are assigned to the 1st Airborne Command Control Squadron (1ACCS) of the 55th Wing at Offutt Air Force Base, Nebraska. Maintenance and crews are provided by Air Combat Command.[1] Operations are coordinated by United States Strategic Command.[1]
[edit] Variants
- E-4A
- E-4B
[edit] Specifications (E-4B)
General characteristics
- Crew: 60-114
- Length: 231 ft 4 in (70.5 m)
- Wingspan: 195 ft 8 in (59.7 m)
- Height: 63 ft 5 in (19.3 m)
- Wing area: 5,500 ft² (510 m²)
- Empty weight: 410,000 lb (190,000 kg)
- Loaded weight: 820,000 lb (370,000 kg)
- Powerplant: 4× General Electric CF6-50E2 turbofans, 52,500 lbf (234 kN) each
Performance
- Maximum speed: 523 knots (602 mph, 969 km/h)
- Range: 6,200 nm (7,100 mi, 11,000 km)
- Service ceiling 45,000 ft (14,000 m)
- Wing loading: 150 lb/ft² (730 kg/m²)
- Thrust/weight: 0.26
[edit] Popular culture
The E-4B plays a prominent role in two motion pictures, appearing in the HBO film "By Dawn's Early Light," and "The Sum of All Fears," based on the book by Tom Clancy.
[edit] See also
Related development
Comparable aircraft
Related lists
[edit] References
[edit] External links
- USAF E-4 fact sheet
- E-4 product page and E-4 history page on Boeing.com
- E-4 page GlobalSecurity.org
- E-4 page on TheAviationZone.com
- "Around the clock with the E-4B", USAF Airman magazine, May 2000.
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