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Boeing VC-25

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A treadmill is a device generally used for walking, running , or climbing while staying in the same place. Treadmills were introduced before the development of powered machines to harness the power of animals or humans to do work, often a type of mill operated by a person or animal treading the steps of a treadwheel to grind grain. In later times, treadmills were used as punishment devices for people sentenced to hard labour in prisons. The terms treadmill and treadwheel were used interchangeably for the power and punishment mechanisms.

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128-653: The Boeing VC-25 is a military version of the Boeing 747 airliner, modified for presidential transport and commonly operated by the United States Air Force (USAF) as Air Force One , the call sign of any U.S. Air Force aircraft carrying the president of the United States. Only two examples of this aircraft type are in service; they are highly modified Boeing 747-200Bs, designated VC-25A and having tail numbers 28000 and 29000. Although technically

256-406: A "cardio mode", where a target heart rate is defined and the speed and elevation (load) are controlled automatically until the subject is in a "heart rate steady state". So the treadmill is delivering mechanical energy to the human body based on the vital function (heart rate) of the subject. A medical treadmill used for ergometry and cardiopulmonary stress tests and performance diagnostics is always

384-610: A $ 569 million post-tax charge against its fourth-quarter 2015 profits. At the end of 2015, the company had 20 orders outstanding. On January 29, 2016, Boeing announced that it had begun the preliminary work on the modifications to a commercial 747-8 for the next Air Force One presidential aircraft, then expected to be operational by 2020. On July 12, 2016, Boeing announced that it had finalized an order from Volga-Dnepr Group for 20 747-8 freighters, valued at $ 7.58 billion (~$ 9.44 billion in 2023) at list prices. Four aircraft were delivered beginning in 2012. Volga-Dnepr Group

512-459: A 5,000-nautical-mile (9,300 km; 5,800 mi) range with a typical 452-passenger payload, and an increased MTOW of 750,000 lb (340 t) was offered. The first -100B order, one aircraft for Iran Air , was announced on June 1, 1978. This version first flew on June 20, 1979, received FAA certification on August 1, 1979, and was delivered the next day. Nine -100Bs were built, one for Iran Air and eight for Saudi Arabian Airlines . Unlike

640-590: A 520,000-pound (240 t) MTOW and Pratt & Whitney JT9D -7A engines derated to 43,000 pounds-force (190 kN) of thrust. Following the -100SR, Boeing produced the -100BSR, a 747SR variant with increased takeoff weight capability. Debuting in 1978, the -100BSR also incorporated structural modifications for a high cycle-to-flying hour ratio; a related standard -100B model debuted in 1979. The -100BSR first flew on November 3, 1978, with first delivery to All Nippon Airways (ANA) on December 21, 1978. A total of 20 -100BSRs were produced for ANA and JAL. The -100BSR had

768-548: A 600,000 pounds (270 t) MTOW and was powered by the same JT9D-7A or General Electric CF6 -45 engines used on the -100SR. ANA operated this variant on domestic Japanese routes with 455 or 456 seats until retiring its last aircraft in March 2006. In 1986, two -100BSR SUD models, featuring the stretched upper deck (SUD) of the -300, were produced for JAL. The type's maiden flight occurred on February 26, 1986, with FAA certification and first delivery on March 24, 1986. JAL operated

896-668: A Russian airline. Before they could be delivered, the company filed for bankruptcy and was closed down; the two aircraft were stored at Southern California Logistics Airport in the Mojave Desert to prevent corrosion. On 27 February 2018, the White House announced a US$ 3.9 billion (~$ 4.66 billion in 2023) agreement with Boeing to modify the two unsold 747-8s to replace the current VC-25As. The new aircraft will be designated VC-25B. These aircraft are to be retrofitted with telecommunications and security equipment to bring them to

1024-416: A class IIb medical device either when used as a stand-alone device in a medical environment or when used in connection with an ECG, EMG, ergospirometry, or blood pressure monitoring device. On the running deck the subject moves, adapting to the adjustable speed of the belt. The running deck is usually mounted on damping elements, so the running deck has shock-absorbing characteristics. A lifting element raises

1152-528: A conveyor; however, tying the leash to the treadmill should be avoided as it can cause serious injury. Underwater treadmills are a type of treadmill encased in glass or plastic and filled with water to a point where the occupant is partially submerged. They are used for both humans and animals, often for physical therapy. Dog/pet and underwater pet treatment treadmills are available for both home and clinical use. A variety of makes and models are available, but key features of treadmills designed for pet use include

1280-602: A different locking mechanism for added security. Many of the VC-25's other capabilities are classified for security reasons. There has been at least one instance of a VC-25A carrying the president of the United States without using the Air Force One call sign, when President George W. Bush went on a secret flight (with the "Gulf Stream Five" call sign) to meet with troops in Iraq on Thanksgiving , on November 27, 2003. After

1408-452: A fully occupied 747. Nonetheless, many flag-carriers purchased the 747 due to its prestige "even if it made no sense economically" to operate. During the 1970s and 1980s, over 30 regularly scheduled 747s could often be seen at John F. Kennedy International Airport . The recession of 1969–1970 , despite having been characterized as relatively mild, greatly affected Boeing. For the year and a half after September 1970, it only sold two 747s in

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1536-428: A good spread of support on the ground and safety in case of tire blow-outs. The main gear are redundant so that landing can be performed on two opposing landing gears if the others are not functioning properly. The 747 also has split control surfaces and was designed with sophisticated triple-slotted flaps that minimize landing speeds and allow the 747 to use standard-length runways. For transportation of spare engines,

1664-405: A high-capacity airliner with enough range to cover Pan Am's New York–Middle Eastern routes and Iran Air's planned Tehran–New York route. The Tehran–New York route, when launched, was the longest non-stop commercial flight in the world. The 747SP is 48 feet 4 inches (14.73 m) shorter than the 747-100. Fuselage sections were eliminated fore and aft of the wing, and the center section of

1792-437: A higher maximum takeoff weight (MTOW) variant, and the -100SR (Short Range), with higher passenger capacity. Increased maximum takeoff weight allows aircraft to carry more fuel and have longer range. The -200 model followed in 1971, featuring more powerful engines and a higher MTOW. Passenger, freighter and combination passenger-freighter versions of the -200 were produced. The shortened 747SP (special performance) with

1920-506: A horizontal axis, requiring the user to step upwards, like walking up an endless staircase. Those punished walked around the outside of the wheel holding a horizontal handrail for stability. By the Prison Act of 1865 every male prisoner over 16, sentenced to hard labour , had to spend three months at least of his sentence in the labour of first class, which consisted primarily of the treadmill. Punishment treadmills remained in use until

2048-433: A large deck of up to 300 cm (120 in) in length and up to 100 cm (39 in) in width. With high physical exertion and an increased risk of falling, a fall-stop unit is required to prevent the subject or patient from falling. This fall-stop device usually takes the form of a safety arch to which a line is attached to an electrical switch. A harness bears the subject, preventing them from falling and shutting down

2176-403: A long "spine" running the length of the aircraft with the wing spar passing through it, while Boeing blended the two, with a longer pod that ran from just behind the nose to just behind the wing. In 1965, Lockheed's aircraft design and General Electric's engine design were selected for the new C-5 Galaxy transport, which was the largest military aircraft in the world at the time. Boeing carried

2304-421: A long corridor runs along the port (left) side. The aircraft also contains a conference room, originally designed as a situation room , but now used for meeting with staff while traveling. This room includes a 50-inch plasma screen television which can be used for teleconferencing. The aircraft has fully equipped office areas with telecommunication systems (including 87 telephones and 19 televisions). On board

2432-410: A longer range was also developed, and entered service in 1976. The 747 line was further developed with the launch of the 747-300 on June 11, 1980, followed by interest from Swissair a month later and the go-ahead for the project. The 300 series resulted from Boeing studies to increase the seating capacity of the 747, during which modifications such as fuselage plugs and extending the upper deck over

2560-448: A longer running surface, open front and back entries and side rails to prevent the pet from falling off the treadmill. None are designed to be used without human supervision. Many veterinary and animal rehabilitation clinics also offer underwater treadmill therapy as part of their services provided to clients' pets. Advanced applications are so-called omnidirectional treadmills. They are designed to move in two dimensions and are intended as

2688-419: A military command center in the event of an incident such as a nuclear attack. Operational modifications include aerial refueling capability and countermeasures against anti-aircraft missiles . The electronics on board are connected with approximately 238 miles (383 km) of wiring, twice that of a regular 747. All wiring is covered with heavy shielding for protection from a nuclear electromagnetic pulse in

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2816-508: A much larger and more capable aircraft was needed, especially to carry cargo that would not fit in any existing aircraft. These studies led to initial requirements for the CX-Heavy Logistics System (CX-HLS) in March 1964 for an aircraft with a load capacity of 180,000 pounds (81.6 t) and a speed of Mach 0.75 (430 kn; 800 km/h), and an unrefueled range of 5,000 nautical miles (9,300 km; 5,800 mi) with

2944-421: A new jet airliner 2 + 1 ⁄ 2 times size of the 707, with a 30% lower cost per unit of passenger-distance and the capability to offer mass air travel on international routes. Trippe also thought that airport congestion could be addressed by a larger new aircraft. In 1965, Joe Sutter was transferred from Boeing's 737 development team to manage the design studies for the new airliner, already assigned

3072-687: A payload of 115,000 pounds (52.2 t). The payload bay had to be 17 feet (5.18 m) wide by 13.5 feet (4.11 m) high and 100 feet (30 m) long with access through doors at the front and rear. The desire to keep the number of engines to four required new engine designs with greatly increased power and better fuel economy. In May 1964, airframe proposals arrived from Boeing, Douglas , General Dynamics , Lockheed , and Martin Marietta ; engine proposals were submitted by General Electric , Curtiss-Wright , and Pratt & Whitney . Boeing, Douglas, and Lockheed were given additional study contracts for

3200-412: A presidential inauguration resulting in a change in office, the outgoing president is provided transport on a VC-25 aircraft to their home destination. The aircraft for this flight does not use the Air Force One call sign because it is not carrying the president in office. For both Presidents Bill Clinton and George W. Bush, the flight was known as Special Air Mission 28000 , where the number represents

3328-482: A private office, or the president's "Oval Office aboard Air Force One". If necessary, the president can address the nation from the office. This capability was added after the September 11 attacks , during which the aircraft had to land at Barksdale Air Force Base for President George W. Bush to address the nation. These offices, including the president's suite, are mostly located on the starboard (right) side, and

3456-462: A range of 4,620 nautical miles (8,556 km), was the original variant launched in 1966. The 747-200 soon followed, with its launch in 1968. The 747-300 was launched in 1980 and was followed by the 747-400 in 1985. Ultimately, the 747-8 was announced in 2005. Several versions of each variant have been produced, and many of the early variants were in production simultaneously. The International Civil Aviation Organization (ICAO) classifies variants using

3584-489: A running deck of up to 450 cm × 300 cm (180 in × 120 in). As a cardiovascular exercise: As an indoor activity: As a machine: As it is a conveyor belt , the treadmill can be used for activities other than running. If horses are being tested (especially in jockey racing) they will be put on a specially constructed treadmill. Large treadmills can also accommodate cars. Treadmills can also be used to exercise dogs that are accustomed to running on

3712-513: A running deck with a rotating belt. Before and after the running deck, there are two shafts. The belt is stretched between the shafts and the running deck. Safety standards for treadmills are IEC EN 957-1 and IEC EN 957-6. For medical treadmills applicable norms, standards and guidelines include the Medical Device Directive (MDD), European Guideline 93/42 EEC, European Guideline 2007/47 EEC, IEC EN 60601-1, EN 62304, EN 14971 and

3840-447: A shortened code formed by combining the model number and the variant designator (e.g. "B741" for all -100 models). The first 747-100s were built with six upper deck windows (three per side) to accommodate upstairs lounge areas. Later, as airlines began to use the upper deck for premium passenger seating instead of lounge space, Boeing offered an upper deck with ten windows on either side as an option. Some early -100s were retrofitted with

3968-496: A single airline before or since. Ultimately, the high-winged CX-HLS Boeing design was not used for the 747, although technologies developed for their bid had an influence. The original design included a full-length double-deck fuselage with eight-across seating and two aisles on the lower deck and seven-across seating and two aisles on the upper deck. However, concern over evacuation routes and limited cargo-carrying capability caused this idea to be scrapped in early 1966 in favor of

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4096-405: A test aircraft was flown to Renton to have test equipment removed and a cabin installed. Pilot Ralph C. Cokely undershot the airport's short runway and the 747's right, outer landing gear was torn off and two engine nacelles were damaged. However, these difficulties did not prevent Boeing from taking a test aircraft to the 28th Paris Air Show in mid-1969, where it was displayed to the public for

4224-439: A time. The president gets a personal menu. An area where guests sit is near the center of the aircraft, outside the "White House". There are separate quarters for guests, senior staff, Secret Service and Air Force security personnel assigned to the plane, and the news media located in the aft area of the main deck. Protocol states that one may wander aft of one's assigned seat, but not forward of it. Communications equipment and

4352-568: A two-crew glass cockpit , was introduced in 1989 and is the most common variant. After several studies, the stretched 747-8 was launched on November 14, 2005, with new General Electric GEnx engines, and was first delivered in October 2011. The 747 is the basis for several government and military variants, such as the VC-25 ( Air Force One ), E-4 Emergency Airborne Command Post, Shuttle Carrier Aircraft , and some experimental test aircraft such as

4480-493: A vertical axis, driven by an ox or other animal walking in a circle and pushing the bar. Humans were also used to power these. The second design was a vertical wheel, a treadwheel , that was powered by climbing in place instead of walking in circles. This is similar to what we know today as the hamster wheel . The third design also required climbing but used a sloped, moving platform instead. Treadmills as muscle-powered engines originated roughly 4000 years ago. Their primary use

4608-448: A wider single deck design. The cockpit was therefore placed on a shortened upper deck so that a freight-loading door could be included in the nose cone; this design feature produced the 747's distinctive "hump". In early models, what to do with the small space in the pod behind the cockpit was not clear, and this was initially specified as a "lounge" area with no permanent seating. (A different configuration that had been considered to keep

4736-424: Is a four-engined jet aircraft , initially powered by Pratt & Whitney JT9D turbofan engines, then General Electric CF6 and Rolls-Royce RB211 engines for the original variants. With a ten-abreast economy seating, it typically accommodates 366 passengers in three travel classes . It has a pronounced 37.5° wing sweep , allowing a Mach 0.85 (490 kn; 900 km/h) cruise speed , and its heavy weight

4864-477: Is a long-range wide-body airliner designed and manufactured by Boeing Commercial Airplanes in the United States between 1968 and 2023. After the introduction of the 707 in October 1958, Pan Am wanted a jet 2 + 1 ⁄ 2 times its size, to reduce its seat cost by 30%. In 1965, Joe Sutter left the 737 development program to design the 747. In April 1966, Pan Am ordered 25 Boeing 747-100 aircraft, and in late 1966, Pratt & Whitney agreed to develop

4992-467: Is supported by four main landing gear legs, each with a four-wheel bogie . The partial double-deck aircraft was designed with a raised cockpit so it could be converted to a freighter airplane by installing a front cargo door, as it was initially thought that it would eventually be superseded by supersonic transports . Boeing introduced the -200 in 1971, with uprated engines for a heavier maximum takeoff weight (MTOW) of 833,000 pounds (378 t) from

5120-513: Is the parent of three major Russian air-freight carriers – Volga-Dnepr Airlines , AirBridgeCargo Airlines and Atran Airlines . The new 747-8 freighters would replace AirBridgeCargo's current 747-400 aircraft and expand the airline's fleet and will be acquired through a mix of direct purchases and leasing over the next six years, Boeing said. On July 27, 2016, in its quarterly report to the Securities and Exchange Commission , Boeing discussed

5248-463: The 767 and Airbus A300 / A310 twinjets ). Having tried replacing coach seats on its 747s with piano bars in an attempt to attract more customers, American Airlines eventually relegated its 747s to cargo service and in 1983 exchanged them with Pan Am for smaller aircraft; Delta Air Lines also removed its 747s from service after several years. Later, Delta acquired 747s again in 2008 as part of its merger with Northwest Airlines , although it retired

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5376-476: The Air Force One designation applies to the aircraft only while the president is on board, the term is commonly used to refer to the VC-25 in general. The two aircraft often operate in conjunction with Marine One helicopters, which ferry the president to airports whenever a vehicle motorcade would be inappropriate. Two new aircraft, based on the Boeing 747-8I and designated VC-25B, have been ordered by

5504-465: The Boeing 747-400 fleet in December 2017. International flights bypassing traditional hub airports and landing at smaller cities became more common throughout the 1980s, thus eroding the 747's original market. Many international carriers continued to use the 747 on Pacific routes. In Japan, 747s on domestic routes were configured to carry nearly the maximum passenger capacity. The 747-100 with

5632-620: The DC-10 were in competition to be selected, with the Boeing entry the eventual winner. The fabrication of the current 747s began during the presidency of Ronald Reagan (1981–1989). The VC-25s were completed in 1986 and first flew in 1987. The interior designs were created by First Lady Nancy Reagan , who used designs reminiscent of the American Southwest . Problems with interior wiring for communication systems delayed delivery of

5760-481: The JT9D engine, a high-bypass turbofan . On September 30, 1968, the first 747 was rolled out of the custom-built Everett Plant , the world's largest building by volume . The 747's first flight took place on February 9, 1969, and the 747 was certified in December of that year. It entered service with Pan Am on January 22, 1970. The 747 was the first airplane called a " Jumbo Jet " as the first wide-body airliner. The 747

5888-670: The YAL-1 and SOFIA airborne observatory. Initial competition came from the smaller trijet widebodies: the Lockheed L-1011 (introduced in 1972), McDonnell Douglas DC-10 (1971) and later MD-11 (1990). Airbus competed with later variants with the heaviest versions of the A340 until surpassing the 747 in size with the A380 , delivered between 2007 and 2021. Freighter variants of the 747 remain popular with cargo airlines. The final 747

6016-422: The cockpit are on the upper deck. There are also secure and non-secure voice, fax and data communications facilities. While the aircraft's luggage capacity is adequate to carry the belongings of the passengers, the logistics train of the president means that the aircraft must fly preceded by an aerial convoy of several cargo transports, which carry the helicopters, motorcade vehicles, and other equipment required by

6144-401: The tailplane (horizontal stabilizer); detailed investigations showed, however, that the best estimate of the exposure to depleted uranium was ".. several orders of magnitude less than the workers' limit for chronic exposure." The flight test program was hampered by problems with the 747's JT9D engines. Difficulties included engine stalls caused by rapid throttle movements and distortion of

6272-506: The -100BSR SUD with 563 seats on domestic routes until their retirement in the third quarter of 2006. While only two -100BSR SUDs were produced, in theory, standard -100Bs can be modified to the SUD certification. Overall, 29 Boeing 747SRs were built. The 747-100B model was developed from the -100SR, using its stronger airframe and landing gear design. The type had an increased fuel capacity of 48,070 US gal (182,000 L), allowing for

6400-497: The 1968 book, Aerobics by Kenneth H. Cooper . Cooper's book noted that individuals who ran for eight minutes four to five times a week would be in better physical condition. Staub noticed that there were no affordable household treadmills at the time and decided to develop one for his use during the late 1960s. He called his first treadmill the PaceMaster 600. Once finished, Staub sent his prototype treadmill to Cooper, who found

6528-487: The 300 series were produced. In 1985, development of the longer range 747-400 began. The variant had a new glass cockpit , which allowed for a cockpit crew of two instead of three, new engines, lighter construction materials, and a redesigned interior. Development costs soared, and production delays occurred as new technologies were incorporated at the request of airlines. Insufficient workforce experience and reliance on overtime contributed to early production problems on

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6656-519: The 747 Advanced that were eventually adopted. Similar in nature to the 747-X, the stretched 747 Advanced used technology from the 787 to modernize the design and its systems. The 747 remained the largest passenger airliner in service until the Airbus A380 began airline service in 2007. On November 14, 2005, Boeing announced it was launching the 747 Advanced as the Boeing 747-8 . The last 747-400s were completed in 2009. As of 2011 , most orders of

6784-549: The 747 can accommodate a non-functioning fifth-pod engine under the aircraft's port wing between the inner functioning engine and the fuselage. The fifth engine mount point was also used by Virgin Orbit 's LauncherOne program to carry an orbital-class rocket to cruise altitude where it was deployed. After the aircraft's introduction with Pan Am in 1970, other airlines that had bought the 747 to stay competitive began to put their own 747s into service. Boeing estimated that half of

6912-468: The 747 had been a major challenge, and building its assembly plant was also a huge undertaking. Boeing president William M. Allen asked Malcolm T. Stamper, then head of the company's turbine division, to oversee construction of the Everett factory and to start production of the 747. To level the site, more than four million cubic yards (three million cubic meters) of earth had to be moved. Time

7040-472: The 747-400, several stretching schemes for the 747 were proposed. Boeing announced the larger 747-500X and -600X preliminary designs in 1996. The new variants would have cost more than US$ 5 billion to develop, and interest was not sufficient to launch the program. In 2000, Boeing offered the more modest 747X and 747X stretch derivatives as alternatives to the Airbus A38X . However, the 747X family

7168-472: The 747-400. The -400 entered service in 1989. In 1991, a record-breaking 1,087 passengers were flown in a 747 during a covert operation to airlift Ethiopian Jews to Israel . Generally, the 747-400 held between 416 and 524 passengers. The 747 remained the heaviest commercial aircraft in regular service until the debut of the Antonov An-124 Ruslan in 1982; variants of the 747-400 surpassed

7296-562: The 747-8 were for the freighter variant. On February 8, 2010, the 747-8 Freighter made its maiden flight . The first delivery of the 747-8 went to Cargolux in 2011. The first 747-8 Intercontinental passenger variant was delivered to Lufthansa on May 5, 2012. The 1,500th Boeing 747 was delivered in June 2014 to Lufthansa. In January 2016, Boeing stated it was reducing 747-8 production to six per year beginning in September 2016, incurring

7424-658: The Air Force posted online an amendment to its Air Force One contract authorizing Boeing to begin preliminary design activities. This version of the contract synopsis confirmed that the government will buy two modified 747-8 aircraft. Boeing was awarded a contract in January 2016 to identify cost reduction opportunities in areas including maintenance, aerial refueling and communications. On 15 July 2016, Boeing received another contract for pre-engineering and manufacturing development (EMD) risk-reduction to address "system specification,

7552-459: The An-124's weight in 2000. The Antonov An-225 Mriya cargo transport , which debuted in 1988, remains the world's largest aircraft by several measures (including the most accepted measures of maximum takeoff weight and length); one aircraft has been completed and was in service until 2022. The Scaled Composites Stratolaunch is currently the largest aircraft by wingspan . After the arrival of

7680-553: The U.S. presidency and its powers; with the White House and presidential seal , it is among the most recognized presidential symbols. Air Force One has often appeared in popular culture and fiction, including the setting of the 1997 action movie Air Force One where the aircraft had an escape pod and a parachute ramp, unlike the actual presidential aircraft. Related development Aircraft of comparable role, configuration, and era Boeing 747 The Boeing 747

7808-514: The US Air Force notice, as assembling only three airplanes in the US would not make financial sense. This made Boeing the only aircraft manufacturer interested in supplying the replacement aircraft, and was reported to be exploring a 787 option also. On 28 January 2015, the Air Force announced the selection of the Boeing 747-8 to replace the aging VC-25A for presidential transport. On 10 May 2016,

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7936-517: The USAF to replace the aging VC-25As. By 1985, the pair of Boeing 707 -based VC-137s used as the presidential aircraft had been in service for 23 and 13 years respectively, and the USAF began searching for an eventual replacement. The Request for Proposal issued stated that the aircraft to be selected should have at least three engines and an unrefueled range of at least 6,000 miles (9,700 km). Both Boeing with its 747 and McDonnell Douglas with

8064-435: The VC-25 has two main decks and a cargo area, like a regular Boeing 747, its 4,000 square feet (370 m) of floor space has been reconfigured for presidential duties. Its lowest level is mostly cargo space, carrying luggage and the onboard food supply. The main passenger area is on the second floor or main deck. The upper deck contains the cockpit and the communications center. Typically, the president boards and disembarks from

8192-429: The VC-25 is a medical annex, which includes a fold-out operating table, emergency medical supplies, and a well-stocked pharmacy. George W. Bush had a treadmill added to Air Force One during his term in office. Every flight is staffed by a doctor and nurse. The aircraft is self-sufficient, such as carrying all the food it will need. Meals are prepared in two galleys , which together are equipped to feed up to 100 people at

8320-472: The aircraft's tail number. The VC-25As have also been used to transport deceased former presidents, as the guest area aft of "the White House" has chairs and tables that can be removed and the casket laid in their place. The bodies of Ronald Reagan, Gerald Ford , and George H.W. Bush were transported to Washington for their state funerals, and then on to their final resting places. Colonel Mark Tillman, pilot for President George W. Bush, said, "We'll take care of

8448-408: The aircraft's upper deck; instead of using a conventional slide, volunteer passengers escaped by using a harness attached to a reel. Tests also involved taxiing such a large aircraft. Boeing built an unusual training device known as "Waddell's Wagon" (named for a 747 test pilot, Jack Waddell) that consisted of a mock-up cockpit mounted on the roof of a truck. While the first 747s were still being built,

8576-462: The airframe, along with General Electric and Pratt & Whitney for the engines. The airframe proposals shared several features. As the CX-HLS needed to be able to be loaded from the front, a door had to be included where the cockpit usually was. All of the companies solved this problem by moving the cockpit above the cargo area; Douglas had a small "pod" just forward and above the wing, Lockheed used

8704-462: The ceremonial 747 contract-signing banquet in Seattle on Boeing's 50th Anniversary, Juan Trippe predicted that the 747 would be "…a great weapon for peace, competing with intercontinental missiles for mankind's destiny". As launch customer, and because of its early involvement before placing a formal order, Pan Am was able to influence the design and development of the 747 to an extent unmatched by

8832-471: The concept but was committed to developing the engine for the C-5 Galaxy and did not enter the commercial market until later. Pratt & Whitney was also working on the same principle and, by late 1966, Boeing, Pan Am and Pratt & Whitney agreed to develop a new engine, designated the JT9D to power the 747. The project was designed with a new methodology called fault tree analysis , which allowed

8960-474: The development process has been hit by multiple "production mishaps", including the discovery of empty tequila mini-bottles on one of the aircraft, and the use of jacks that were not rated to support the weight of the aircraft. While the jacking did not result in damage to the planes, "the Pentagon's contractor-management agency formally requested Boeing improve its operations." While the initial delivery date

9088-475: The device allowed pilots to practice taxi maneuvers from a high upper-deck position. In 1968, the program cost was US$ 1 billion (equivalent to $ 6.7 billion in 2023 dollars). On September 30, 1968, the first 747 was rolled out of the Everett assembly building before the world's press and representatives of the 26 airlines that had ordered the airliner. Over the following months, preparations were made for

9216-412: The early 747 sales were to airlines desiring the aircraft's long range rather than its payload capacity. While the 747 had the lowest potential operating cost per seat, this could only be achieved when the aircraft was fully loaded; costs per seat increased rapidly as occupancy declined. A moderately loaded 747, one with only 70 percent of its seats occupied, used more than 95 percent of the fuel needed by

9344-490: The effects of a failure of a single part to be studied to determine its impact on other systems. To address concerns about safety and flyability, the 747's design included structural redundancy, redundant hydraulic systems, quadruple main landing gear and dual control surfaces. Additionally, some of the most advanced high-lift devices used in the industry were included in the new design, to allow it to operate from existing airports. These included Krueger flaps running almost

9472-425: The empennage. As Boeing did not have a plant large enough to assemble the giant airliner, they chose to build a new plant. The company considered locations in about 50 cities, and eventually decided to build the new plant some 30 miles (50 km) north of Seattle on a site adjoining a military base at Paine Field near Everett , Washington. It bought the 780-acre (320 ha) site in June 1966. Developing

9600-582: The entire frame including the running deck and simulates a pitch angle for uphill running. Some treadmills can also reverse the running belt to simulate downhill loads. Most treadmills for professional use in the fitness area have table sizes of about 150 cm (59 in) long and 50 cm (20 in) width, a speed range of about 0–20 km/h (0–12 mph) and slope angle of 0–20%. Larger, more stable treadmills are required for athletes. With some weight relief, sprinters reach temporary speeds of up to 45 km/h (28 mph) and must therefore run on

9728-403: The entire length of the fuselage were rejected. The first 747-300, completed in 1983, included a stretched upper deck, increased cruise speed, and increased seating capacity. The -300 variant was previously designated 747SUD for stretched upper deck, then 747-200 SUD, followed by 747EUD, before the 747-300 designation was used. Passenger, short range and combination freighter-passenger versions of

9856-409: The entire length of the wing's leading edge, as well as complex three-part slotted flaps along the trailing edge of the wing. The wing's complex three-part flaps increase wing area by 21% and lift by 90% when fully deployed compared to their non-deployed configuration. Boeing agreed to deliver the first 747 to Pan Am by the end of 1969. The delivery date left 28 months to design the aircraft, which

9984-443: The environmental control system, the aircraft interior, the electrical and power system and sustainment and maintenance approaches" to reduce development risks and life-cycle costs. On 1 August 2017, Defense One reported that in an effort to pay less for the replacement program, the USAF entered into a contract to purchase two 747-8 Intercontinental (747-8I) jets from Boeing, which had originally been ordered in 2011 by Transaero ,

10112-486: The evacuation of 560 volunteers from a cabin mock-up via the aircraft's emergency chutes. The first full-scale evacuation took two and a half minutes instead of the maximum of 90 seconds mandated by the Federal Aviation Administration (FAA), and several volunteers were injured. Subsequent test evacuations achieved the 90-second goal but caused more injuries. Most problematic was evacuation from

10240-542: The event of a nuclear attack. The aircraft also has electronic countermeasures (ECMs) (AN/ALQ-204 Matador) to jam enemy radar, flares to avoid heat-seeking missiles, and chaff to avoid radar-guided missiles. All small arms and ammunition stores not in the physical possession of the Secret Service and Air Force security personnel on board the VC-25s are stowed and secured in separate locked compartments, each with

10368-504: The events of an emergency if they cannot do so through the cabin. The 747's maximum takeoff weight ranges from 735,000 pounds (333 t) for the -100 to 970,000 pounds (440 t) for the -8. Its range has increased from 5,300 nautical miles (9,800 km; 6,100 mi) on the -100 to 8,000 nautical miles (15,000 km; 9,200 mi) on the -8I. The 747 has redundant structures along with four redundant hydraulic systems and four main landing gears each with four wheels; these provide

10496-674: The first deviation from the Raymond Loewy livery scheme since it was introduced in 1962 on the VC-137C which was first used as Air Force One during the Kennedy administration . The Biden administration abandoned the new design, citing "additional engineering, as well as increased time and cost." A modified version of the traditional scheme was announced in March 2023. The 747s began undergoing modification work at Boeing's San Antonio facility in 2020. According to The Wall Street Journal ,

10624-433: The first flight, which took place on February 9, 1969, with test pilots Jack Waddell and Brien Wygle at the controls and Jess Wallick at the flight engineer's station. Despite a minor problem with one of the flaps, the flight confirmed that the 747 handled extremely well. The 747 was found to be largely immune to " Dutch roll ", a phenomenon that had been a major hazard to the early swept-wing jets. During later stages of

10752-612: The first in 2027, and the second in 2028. The VC-25A aircraft are aging and have become less cost-effective to operate. The USAF Air Mobility Command investigated possible replacements, with early press coverage suggesting that the USAF would consider the Boeing 747-8 and the Airbus A380 . On 7 January 2009, Air Force Materiel Command issued a new Sources Sought notice for a replacement aircraft to enter service by 2017 with an additional two aircraft to follow in 2019 and 2021. On 28 January 2009, EADS North America representing EADS and its Airbus division confirmed it would not respond to

10880-410: The first time. Finally, in December 1969, the 747 received its FAA airworthiness certificate , clearing it for introduction into service. The huge cost of developing the 747 and building the Everett factory meant that Boeing had to borrow heavily from a banking syndicate. During the final months before delivery of the first aircraft, the company had to repeatedly request additional funding to complete

11008-411: The flight by more than six hours to the following day when Clipper Victor (registration N736PA) was used. The 747 enjoyed a fairly smooth introduction into service, overcoming concerns that some airports would not be able to accommodate an aircraft that large. Although technical problems occurred, they were relatively minor and quickly solved. After the initial 747-100, Boeing developed the -100B ,

11136-431: The flight deck out of the way for freight loading had the pilots below the passengers, and was dubbed the "anteater".) One of the principal technologies that enabled an aircraft as large as the 747 to be drawn up was the high-bypass turbofan engine . This engine technology was thought to be capable of delivering double the power of the earlier turbojets while consuming one-third less fuel. General Electric had pioneered

11264-541: The flight test program, flutter testing showed that the wings suffered oscillation under certain conditions. This difficulty was partly solved by reducing the stiffness of some wing components. However, a particularly severe high-speed flutter problem was solved only by inserting depleted uranium counterweights as ballast in the outboard engine nacelles of the early 747s. This measure caused some concern when these aircraft crashed, for example El Al Flight 1862 at Amsterdam in 1992 with 622 pounds (282 kg) of uranium in

11392-664: The front, main deck entrance using a mobile stairway , while journalists and other passengers enter at the rear door of the main deck. However, the aircraft also has built-in airstairs that lead to the lower deck, typically used when security concerns make the use of a mobile stairway impractical. The front section of the aircraft is informally called the "White House", a reference to the president's official residence in Washington, D.C. The president's executive suite includes sleeping quarters with two couches that can be converted into beds, lavatory and shower, vanity, double sink, and

11520-538: The fuselage was redesigned to fit mating fuselage sections. The SP's flaps used a simplified single-slotted configuration. The 747SP, compared to earlier variants, had a tapering of the aft upper fuselage into the empennage , a double-hinged rudder, and longer vertical and horizontal stabilizers. Power was provided by Pratt & Whitney JT9D-7(A/F/J/FW) or Rolls-Royce RB211-524 engines. Treadmill More recently, treadmills have instead been used as exercise machines for running or walking in one place. Rather than

11648-479: The initial 735,000 pounds (333 t), increasing the maximum range from 4,620 to 6,560 nautical miles [nmi] (8,560 to 12,150 km; 5,320 to 7,550 mi). It was shortened for the longer-range 747SP in 1976, and the 747-300 followed in 1983 with a stretched upper deck for up to 400 seats in three classes. The heavier 747-400 with improved RB211 and CF6 engines or the new PW4000 engine (the JT9D successor), and

11776-465: The machine's first customers, including sellers of fitness equipment. Staub began producing the first home treadmills at his plant in Clifton, New Jersey , before moving production to Little Falls, New Jersey . Treadmills as power sources originated in antiquity. These ancient machines had three major types of design. The first was a horizontal bar jutting out of a vertical shaft. It rotated around

11904-442: The machinery directive 2006/42/EC. Medical treadmills are class IIb active therapeutic devices and also active devices for diagnosis. With their very powerful (e.g. 3.3 kW = 4.5  HP) electric motor-powered drive system, treadmills deliver mechanical energy to the human body through the moving running belt of the treadmill. The subject does not change their horizontal position and is passively moved and forced to catch up with

12032-466: The main deck, the cockpit creates a hump. This raised cockpit allows front loading of cargo on freight variants. The upper deck behind the cockpit provides space for a lounge and/or extra seating. The "stretched upper deck" became available as an alternative on the 747-100B variant and later as standard beginning on the 747-300. The upper deck was stretched more on the 747-8. The 747 cockpit roof section also has an escape hatch from which crew can exit during

12160-549: The model number 747. Sutter began a design study with Pan Am and other airlines to better understand their requirements. At the time, many thought that long-range subsonic airliners would eventually be superseded by supersonic transport aircraft. Boeing responded by designing the 747 so it could be adapted easily to carry freight and remain in production even if sales of the passenger version declined. In April 1966, Pan Am ordered 25 Boeing 747-100 aircraft for US$ 525 million (equivalent to $ 3.8 billion in 2023 dollars). During

12288-434: The motion, moving only when walkers push the belt with their feet. The latter are known as manual treadmills. Treadmills continue to be the biggest-selling exercise equipment category by a large margin. As a result, the treadmill industry has hundreds of manufacturers throughout the world. William Staub , a mechanical engineer, developed the first consumer treadmill for home use. Staub developed his treadmill after reading

12416-417: The new configuration. The -100 was equipped with Pratt & Whitney JT9D -3A engines. No freighter version of this model was developed, but many 747-100s were converted into freighters as 747-100(SF). The first 747-100(SF) was delivered to Flying Tiger Line in 1974. A total of 168 747-100s were built; 167 were delivered to customers, while Boeing kept the prototype, City of Everett . In 1972, its unit cost

12544-446: The nose door and raised cockpit concepts over to the design of the 747. The 747 was conceived while air travel was increasing in the 1960s. The era of commercial jet transportation, led by the enormous popularity of the Boeing 707 and Douglas DC-8 , had revolutionized long-distance travel. In this growing jet age, Juan Trippe , president of Pan American Airways (Pan Am), one of Boeing's most important airline customers, asked for

12672-446: The original -100, the -100B was offered with Pratt & Whitney JT9D-7A, CF6-50, or Rolls-Royce RB211-524 engines. However, only RB211-524 (Saudia) and JT9D-7A (Iran Air) engines were ordered. The last 747-100B, EP-IAM was retired by Iran Air in 2014, the last commercial operator of the 747-100 and -100B. The development of the 747SP stemmed from a joint request between Pan American World Airways and Iran Air , who were looking for

12800-610: The potential termination of 747 production due to insufficient demand and market for the aircraft. With a firm order backlog of 21 aircraft and a production rate of six per year, program accounting had been reduced to 1,555 aircraft. In October 2016, UPS Airlines ordered 14 -8Fs to add capacity, along with 14 options, which it took in February 2018 to increase the total to 28 -8Fs on order. The backlog then stood at 25 aircraft, though several of these were orders from airlines that no longer intended to take delivery. On July 2, 2020, it

12928-401: The presence of Pan Am chairman Najeeb Halaby . Instead of champagne, red, white, and blue water was sprayed on the aircraft. The 747 entered service on January 22, 1970, on Pan Am's New York–London route; the flight had been planned for the evening of January 21, but engine overheating made the original aircraft (Clipper Young America, registration N735PA) unusable. Finding a substitute delayed

13056-414: The president from basically when he's in office to when he lays in state." For the funeral of President Ronald Reagan in 2004, Tillman said that the crew converted the front of the aircraft to look the way it would have appeared when Reagan was president; President and Nancy Reagan 's Air Force One jackets were placed on the chairs to "make them feel at home". A specially designed hydraulic lifter (similar to

13184-743: The presidential entourage. The VC-25A replaced the VC-137C (a military version of the Boeing 707 ) as the mainstay of the Air Force One fleet. On some occasions, the VC-25s serve as transport for the US vice president, for which service they use the Air Force Two call sign. The VC-25A aircraft are maintained and operated as military operations by the Presidential Airlift Group, part of Air Mobility Command 's 89th Airlift Wing, based at Joint Base Andrews in Camp Springs, Maryland . The aircraft can also be operated as

13312-426: The production line on December 6, 2022, and was delivered on January 31, 2023. Boeing hosted an event at the Everett factory for thousands of workers as well as industry executives to commemorate the delivery. The Boeing 747 is a large, wide-body (two-aisle) airliner with four wing-mounted engines. Its wings have a high sweep angle of 37.5° for a fast, efficient cruise speed of Mach 0.84 to 0.88, depending on

13440-496: The project. Had this been refused, Boeing's survival would have been threatened. The firm's debt exceeded $ 2 billion, with the $ 1.2 billion owed to the banks setting a record for all companies. Allen later said, "It was really too large a project for us." Ultimately, the gamble succeeded, and Boeing held a monopoly in very large passenger aircraft production for many years. On January 15, 1970, First Lady Pat Nixon christened Pan Am's first 747 at Dulles International Airport in

13568-489: The required security level for the presidential aircraft. In April 2022, Boeing's CEO Dave Calhoun revealed that he expects the company to have a loss of $ 660 million on the VC-25B program, after the contract was renegotiated by President Trump. In June 2019, President Trump announced his plans to revamp the VC-25's livery from the traditional white and ultramarine shades to one of red, white, and blue. This would have been

13696-504: The running belt if necessary. Motorized or manual treadmills can use a slat belt design instead of a traditional continuous treadmill belt. Slat belt treadmills have individual rubberized slats that support shod or unshod walking and running. In some offices, employees are provided with treadmill desks so that employees can walk while working on a computer or speaking on the phone. In treatment centers, treadmills are used with built-in seats left and right for therapists, for example, so

13824-582: The running belt underneath their feet. The subject can also be attached in a safety harness, unweighting system, various supports or even fixed in and moved with a robotic orthotic system utilizing the treadmill. Medical treadmills are also active measuring devices. When connected through an interface with ECG , ergospirometry , blood pressure monitor (BPM), or EMG , they become a new medical system (e.g., stress test system or cardiopulmonary rehabilitation system) and can also be equipped to measure VO₂ max and various other vital functions. Most treadmills have

13952-399: The second half of the 19th century; they were typically twenty-foot (0,6 m) long paddle wheels with twenty-four steps around a six-foot (1,82 m) cylinder. Several prisoners stood side-by-side on a wheel and had to work six or more hours a day, effectively climbing 5,000 to 14,000 vertical feet (1500 to 4000 m). While the purpose was mainly punitive, the most infamous mill at Brixton Prison

14080-430: The standard 747. The initial 747SR model, the -100SR, had a strengthened body structure and landing gear to accommodate the added stress accumulated from a greater number of takeoffs and landings. Extra structural support was built into the wings, fuselage, and the landing gear along with a 20% reduction in fuel capacity. The initial order for the -100SR – four aircraft for Japan Air Lines (JAL, later Japan Airlines ) –

14208-440: The therapists can move the legs of a stroke patient to simulate walking movements and help them learn to walk again. This is called manual locomotion therapy. Oversized treadmills are also used for cycling at speeds up to 80 km/h (50 mph), for wheelchair users and in special applications with sturdy running belts for cross-country skiing and biathlon, where athletes perform training and testing exercises with roller skis on

14336-434: The turbine casings after a short period of service. The problems delayed 747 deliveries for several months; up to 20 aircraft at the Everett plant were stranded while awaiting engine installation. The program was further delayed when one of the five test aircraft suffered serious damage during a landing attempt at Renton Municipal Airport , the site of Boeing's Renton factory . The incident happened on December 13, 1969, when

14464-426: The two aircraft until 1990, during the administration of George H. W. Bush . The Air Force reported that the operating cost for each VC-25A in 2014 was $ 210,877 (~$ 267,357 in 2023) per hour. The VC-25 is capable of flying 7,800 miles (12,600 km)—roughly one-third the distance around the world—without refueling. The VC-25A can accommodate more than 70 passengers. Each VC-25A cost approximately $ 325 million. While

14592-493: The type used by airline catering) with the presidential seal affixed to the sides lifts the casket up to the portside aft door to enter the VC-25A. The tradition of placing the caskets in the passenger cabin dates back to the assassination of John F. Kennedy , when the crew did not want the president's body placed in the cargo hold, and again during the state funeral of Lyndon B. Johnson . The two VC-25As are slated for retirement,

14720-513: The user powering a mill, the device provides a moving platform with a wide conveyor belt driven by an electric motor or a flywheel . The belt moves to the rear, requiring the user to walk or run at a speed matching the belt. The rate at which the belt moves is the rate of walking or running. Thus, the speed of running may be controlled and measured. The more expensive, heavy-duty versions are motor-driven (usually by an electric motor). The simpler, lighter, and less expensive versions passively resist

14848-422: The variant. The sweep also reduces the wingspan, allowing the 747 to use existing hangars . Its seating capacity is over 366 with a 3–4–3 seat arrangement (a cross section of three seats, an aisle, four seats, another aisle, and three seats) in economy class and a 2–3–2 layout in first class on the main deck. The upper deck has a 3–3 seat arrangement in economy class and a 2–2 layout in first class. Raised above

14976-476: The world, both to Irish flag carrier Aer Lingus . No 747s were sold to any American carrier for almost three years. When economic problems in the US and other countries after the 1973 oil crisis led to reduced passenger traffic, several airlines found they did not have enough passengers to fly the 747 economically, and they replaced them with the smaller and recently introduced McDonnell Douglas DC-10 and Lockheed L-1011 TriStar trijet wide bodies (and later

15104-540: Was US$ 24M (174.8M today). Responding to requests from Japanese airlines for a high-capacity aircraft to serve domestic routes between major cities, Boeing developed the 747SR as a short-range version of the 747-100 with lower fuel capacity and greater payload capability. With increased economy class seating, up to 498 passengers could be carried in early versions and up to 550 in later models. The 747SR had an economic design life objective of 52,000 flights during 20 years of operation, compared to 24,600 flights in 20 years for

15232-508: Was announced on October 30, 1972; rollout occurred on August 3, 1973, and the first flight took place on August 31, 1973. The type was certified by the FAA on September 26, 1973, with the first delivery on the same day. The -100SR entered service with JAL, the type's sole customer, on October 7, 1973, and typically operated flights within Japan. Seven -100SRs were built between 1973 and 1975, each with

15360-509: Was delivered to Atlas Air in January 2023 after a 54-year production run, with 1,574 aircraft built. As of December 2023 , 64 Boeing 747s (4.1%) have been lost in accidents and incidents , in which a total of 3,746 people have died. In 1963, the United States Air Force started a series of study projects on a very large strategic transport aircraft. Although the C-141 Starlifter was being introduced, officials believed that

15488-411: Was installed in 1821 and used to grind grain to supplement an existing windmill which Cubitt had previously installed nearby. It gained notoriety for the cruelty with which it was used, which then became a popular satirical metaphor for early-19th century prisons. The machines could also pump water or power ventilators in mines. The first US patent for a treadmill "training machine" (#1,064,968)

15616-921: Was issued on June 17, 1913. The forerunner of the exercise treadmill was designed to diagnose heart and lung diseases, and was invented by Robert Bruce and Wayne Quinton at the University of Washington in 1952. Kenneth H. Cooper 's research on the benefits of aerobic exercise, published in 1968, provided a medical argument to support the commercial development of the home treadmill and exercise bike. Among users of treadmills today are medical facilities (hospitals, rehabilitation centers, medical and physiotherapy clinics, institutes of higher education), sports clubs, biomechanics institutes, orthopedic shoe shops, running shops, Olympic training centers, universities, fire-training centers, NASA, test facilities, police forces and armies, gyms and even home users. Treadmill ergometers are now mainly motor driven. Most treadmills have

15744-563: Was reported that Boeing planned to end 747 production in 2022 upon delivery of the remaining jets on order to UPS and the Volga-Dnepr Group due to low demand. On July 29, 2020, Boeing confirmed that the final 747 would be delivered in 2022 as a result of "current market dynamics and outlook" stemming from the COVID-19 pandemic , according to CEO David Calhoun. The last aircraft, a 747-8F for Atlas Air registered N863GT, rolled off

15872-466: Was set to 2024, the Pentagon expects the jets to be two to three years late, with the Air Force projecting delivery of the first VC-25B in 2027, and the other in 2028, as of a 2023 press release. Once the new aircraft are delivered, the VC-25As will be retired and placed in museums. Data from Boeing BDS General characteristics Performance The VC-25 "Air Force One" is a prominent symbol of

16000-409: Was so short that the 747's full-scale mock-up was built before the factory roof above it was finished. The plant is the largest building by volume ever built, and has been substantially expanded several times to permit construction of other models of Boeing wide-body commercial jets. Before the first 747 was fully assembled, testing began on many components and systems. One important test involved

16128-537: Was to lift buckets of water. This same technology was later adapted to create rotary grain mills and the treadwheel crane . It was also used to pump water and power dough-kneading machines and bellows. Treadmills for punishment were introduced in 1818 by an English engineer named Sir William Cubitt , who was the son of a miller. Noting idle prisoners at Bury St Edmunds gaol , he proposed using their muscle power to both cure their idleness and produce useful work. Cubitt's treadmills for punishment usually rotated around

16256-606: Was two-thirds of the normal time. The schedule was so fast-paced that the people who worked on it were given the nickname "The Incredibles". Developing the aircraft was such a technical and financial challenge that management was said to have "bet the company" when it started the project. Due to its massive size, Boeing subcontracted the assembly of subcomponents to other manufacturers, most notably Northrop and Grumman (later merged into Northrop Grumman in 1994) for fuselage parts and trailing edge flaps respectively, Fairchild for tailplane ailerons, and Ling-Temco-Vought (LTV) for

16384-656: Was unable to attract enough interest to enter production. A year later, Boeing switched from the 747X studies to pursue the Sonic Cruiser , and after the Sonic Cruiser program was put on hold, the 787 Dreamliner . Some of the ideas developed for the 747X were used on the 747-400ER , a longer range variant of the 747-400. After several variants were proposed but later abandoned, some industry observers became skeptical of new aircraft proposals from Boeing. However, in early 2004, Boeing announced tentative plans for

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