The Fokker 100 is a medium-sized, twin-turbofan jet airliner from Fokker, the largest such aircraft built by the company before its bankruptcy in 1996. The type possessed low operational costs and had scant competition in the 100-seat short-range regional jet class, contributing to strong sales upon introduction in the late 1980s. However, an increasing number of similar airliners were brought to market by competitors during the 1990s, leading to a substantial decline in both sales and long-term prospects for the 100. Fokker encountered financial difficulties and was bought up by Deutsche Aerospace AG, which in turn had financial troubles of its own, restricting its ability to support multiple regional airliner programmes. Accordingly, in 1997, production of the Fokker 100 was terminated after 283 airframes had been delivered. By July 2017, a total of 113 Fokker 100 aircraft remained in airline service with 25 airlines around the world. Although airlines are retiring the aircraft, there are still large numbers in operation in both Australia and Iran.
The F28 Mark 0100 “Fokker 100” is based on the Fokker F28 Mark 4000 re-engineed with two Rolls-Royce RB.183 Tay high by-pass ratio turbofans and a fuselage stretched by 18.83 ft. Its wing is wider by 9.8 ft, has new flaps and larger ailerons, extended leading and trailing edges improve aerodynamics and increase the wing chord. The landing gear is strengthened and has new wheels and brakes, the horizontal stabilizer is widened by 4.6 ft. Maximum weights are increased while fuel capacity, max speed and ceiling remain the same, passenger capacity went from 85 to 109; the flight deck went digital with a flight management system, an autopilot/flight director including CAT III autoland, thrust management system, electronic flight instrument displays and full ARINC avionics. The new wing was claimed to be 30% more efficient in cruise, while retaining the simplicity of a fixed leading edge; the cockpit was updated with a Rockwell Collins DU-1000 EFIS. Like the Fokker Fellowship, the Fokker 100 retained the twin rear fuselage-mounted engines and T-tail configuration, like the Douglas DC-9 family.
It lacks the F28 eyebrow windows above the cockpit. A Type Certificate was applied for on 25 March 1983; the program was announced in 1983. A pair of prototypes were built. On 30 November 1986, the first prototype, PH-MKH, flew for the first time, while the second, PH-MKC, followed on 25 February 1987; the variant was approved on 20 November 1987. In February 1988, the first deliveries of the Tay 620-15 powered versions started to Swissair. Major customers included American Airlines with 75 orders, TAM Transportes Aéreos Regionais with 50 and USAir with 40, their aircraft were powered by the more powerful Tay 650-15. During the early 1990s, Fokker and DASA explored a commercial relationship for regional aircraft. DASA purchased 40% of Fokker in 1993. However, by 1995, both Fokker and DASA were suffering financial difficulties, leading to DASA leaving the regional aircraft market. In June 1996, DASA sold the majority of Dornier to Fairchild Aircraft, leading to the creation of Fairchild Dornier, emerging as the third largest regional aircraft manufacturer.
Although the Fokker 100 was successful, Fokker accumulated losses for several years, contributing to its collapse in 1996. Fokker 100 production stopped in early 1997. Discussions regarding the potential for either portions or the entirety of Fokker being purchased by Bombardier Inc. are known to have taken place, but talks fell through without a deal being reached. Dutch firm Stork B. V. has since acquired the maintenance business for the type and has since been providing services to existing operators, having adopted the name Fokker Aviation. Like any number of regional airliner designs, the Fokker 70/100 was being squeezed from below by stretched versions of the Bombardier and Embraer regional jets. At one point, there was a proposal for a stretched version of the Fokker 100, known as the Fokker 130, however this was never built. In 1999, it was announced that an Amsterdam-based group, Rekkof Restart, had entered into negotiations with the intention of reopening both the Fokker 70 and 100 lines.
During the 2000s, the Netherlands Aircraft Company was formed for the purpose of restarting production. However, the ambition has suffered some delays, including some false starts. In March 2010, NG Aircraft stated that it had securing funding from the Ministry of Economic Affairs to adapt an existing Fokker 100 to serve as a prototype for a planned improved new-build series. In March 2011, it was announced that the government of Brazil had formed a partnership for the revival of the Fokker 100. In July 2014, Maarten Van Eeghen, chief executive of NG Aircraft, revealed more details about the pending revival and the new generation of aircraft that would be produced. Dubbed the F120NG, it would be a new-build aircraft, seating a maximum of 125 to 130 passengers, that would be a stretched model of the base Fokker 100, it would adopt a new powerplant, the Pratt & Whitney PurePower PW1X17G turbofan engine rated at 17,600 lb thrust, claimed to result in the new generation airliner burning 50 per cent less fuel per seat than the original Fokker 100.
It was claimed in 2014 that the earliest entry-to-service date for the F120NG would be 2019, based on a five-year development and te
Nav Canada is a run, not-for-profit corporation that owns and operates Canada's civil air navigation system. It was established in accordance with the Civil Air Navigation Services Commercialization Act; the company employs 1,900 air traffic controllers, 650 flight service specialists and 700 technologists. It has been responsible for the safe and expeditious flow of air traffic in Canadian airspace since November 1, 1996 when the government transferred the ANS from Transport Canada to Nav Canada; as part of the transfer, or privatization, Nav Canada paid the government CA$1.5 billion. Nav Canada manages 12 million aircraft movements a year for 40,000 customers in over 18 million square kilometres, making it the world’s second-largest air navigation service provider by traffic volume. Nav Canada, which operates independently of any government funding, is headquartered in Ottawa, Ontario, it is only allowed to be funded by service charges to aircraft operators. Nav Canada's operations consist of various sites across the country.
These include: About 1,400 ground-based navigation aids 55 flight service stations 8 flight information centres, one each in: Kamloops – most of British Columbia Edmonton – all of Alberta and northeastern BC Winnipeg – northwestern Ontario, all of Manitoba and Saskatchewan London – most of Ontario North Bay – all of Nunavut and Northwest Territories, most of the Arctic waters Quebec City – all of Quebec, southwestern Labrador, tip of eastern Ontario, northern New Brunswick Halifax – most of New Brunswick, Nova Scotia, Prince Edward Island, most of Newfoundland and Labrador Whitehorse – northwestern British Columbia and all of Yukon 41 control towers 46 radar sites and 15 automatic dependent surveillance-broadcast ground sites 7 Area Control Centres, one each in: Vancouver – Surrey, BC Edmonton – Edmonton International Airport Winnipeg – Winnipeg-James Armstrong Richardson International Airport Toronto Centre – Toronto-Pearson International Airport Montreal Centre – Montreal-Trudeau International Airport Moncton – Riverview, New Brunswick Gander – Gander International Airport North Atlantic Oceanic control centre: Gander ControlNav Canada has three other facilities: National Operations Centre: Ottawa Technical Systems Centre: Ottawa The Nav Centre – 1950 Montreal Road in Cornwall, Ontario As a non-share capital corporation, Nav Canada has no shareholders.
The company is governed by a 15-member board of directors representing the four stakeholder groups that founded Nav Canada. The four stakeholders elect 10 members as follows: These 10 directors elect four independent directors, with no ties to the stakeholder groups; those 14 directors appoint the president and chief executive officer who becomes the 15th board member. This structure ensures that the interests of individual stakeholders do not predominate and no member group could exert undue influence over the remainder of the board. To further ensure that the interests of Nav Canada are served, these board members cannot be active employees or members of airlines, unions, or government; the company was formed on November 1, 1996 when the government sold the country's air navigation services from Transport Canada to the new not-for-profit private entity for CAD$1.5 billion. The company was formed in response to a number of issues with Transport Canada's operation of air traffic control and air navigation facilities.
While TC's safety record and operational staff were rated its infrastructure was old and in need of serious updating at a time of government restraint. This resulted in system delays for airlines and costs that were exceeding the airline ticket tax, a directed tax, supposed to fund the system; the climate of government wage freezes resulted in staff shortages of air traffic controllers that were hard to address within a government department. Having TC as the service provider, the regulator and inspector was a conflict of interest. Pressure from the airlines on the government mounted for a solution to the problem, hurting the air industry's bottom line. A number of solutions were considered, including forming a crown corporation, but rejected in favour of outright privatization, the new company being formed as a non-share-capital not-for-profit, run by a board of directors who were appointed and now elected; the company's revenue is predominately from service fees charged to aircraft operators which amount to about CAD$1.2B annually.
Nav Canada raises revenues from developing and selling technology and related services to other air navigation service providers around the world. It has some smaller sources of income, such as conducting maintenance work for other ANS providers and rentals from the Nav Centre in Cornwall, Ontario. To address the old infrastructure it purchased from the Canadian government the company has carried out projects such as implementing a wide area multilateration system, replacing 95 Instrument Landing System installations with new equipment, new control towers in Toronto and Calgary, modernizing the Vancouver Area Control Centre and building a new logistics centre Nav Canada felt the impact of the late-2000s recession in two ways: losses in its investments in third party sponsored asset-backed commercial paper and falling revenues due to reduced air traffic levels. In the summer of 2007 the company held $368 million in ABCP. On 12 January 2009 final Ontario Superior Court of Justice approval was granted to restructure the third party ABCP notes.
The company expects that the non-credit related fai
McDonnell Douglas MD-80
The McDonnell Douglas MD-80 is a series of twin-engine, short- to medium-range, single-aisle commercial jetliners. It was lengthened and updated from the DC-9; this series can seat from 130 to 172 passengers depending on seating configuration. The MD-80 series was introduced into commercial service on October 1980 by Swissair; the series includes the MD-81, MD-82, MD-83, MD-87, MD-88. These all have the same fuselage length except the shortened MD-87; the series was followed into service in modified form by the MD-90 in 1995 and the Boeing 717 in 1999. Douglas Aircraft developed the DC-9 in the 1960s as a short-range companion to their larger DC-8; the DC-9 was an all-new design, using two rear fuselage-mounted turbofan engines, a T-tail. The DC-9 has a narrow-body fuselage design with five-abreast seating, holds 80 to 135 passengers depending on seating arrangement and aircraft version; the DC-9 family was produced in 2441 units: 976 DC-9s, 1191 MD-80s, 116 MD-90s and 155 Boeing 717s.. The development of MD-80 series began in the 1970s as a lengthened, growth version of the DC-9-50, with a higher maximum take-off weight and a higher fuel capacity.
Availability of newer versions of the Pratt & Whitney JT8D engine with higher bypass ratios drove early studies including designs known as Series 55, Series 50, Series 60. The design effort focused on the Series 55 in August 1977. With the projected entry into service in 1980, the design was marketed as the "DC-9 Series 80". Swissair launched the Series 80 in October 1977 with an order for 15 plus an option for five; the MD-80 is a medium-range airliner. The series featured a fuselage 14 ft 3 in longer than the DC-9-50; the DC-9's wing design was enlarged by adding sections at the wing root and tip for a 28% larger wing. The initial Series 80 first flew October 19, 1979, it was certified as a version of the DC-9. It was the second generation of the DC-9 called the DC-9-80 and the DC-9 Super 80; the design was the second generation of the DC-9 with two rear fuselage-mounted turbofan engines, small efficient wings, a T-tail. The aircraft has distinctive five-abreast seating in the coach class; the aircraft series was designed for frequent, short-haul flights for 130 to 172 passengers depending on plane version and seating arrangement.
The MD-80 versions have cockpit and aerodynamic upgrades along with the more powerful, more efficient and quieter JT8D-200 series engines, which are a significant upgrade over the smaller JT8D-15, -17, -11, -9 series. The MD-80 series aircraft have longer fuselages than their earlier DC-9 counterparts, as well as longer range; some customers, such as American Airlines, still refer to the planes in fleet documentation as "Super 80". Comparable airliners to the MD-80 series include the Boeing 737-400 and Airbus A320; the first MD-80, DC-9 line number 909, made its first flight on October 19, 1979. Test flying, despite two aircraft damaged in accidents, was completed on August 25, 1980, when the first variant of MD-80, the JT8D-209-powered MD-81, was certified under an amendment to the FAA type certificate for the DC-9; the flight-testing leading up to certification had involved three aircraft accumulating a total of 1,085 flying hours on 795 flights. The first delivery, to launch customer Swissair took place on September 13, 1980.
As the MD-80 was not in effect a new aircraft, it continues to be operated under an amendment to the original DC-9 FAA aircraft type certificate. The type certificate issued to the aircraft manufacturer carries the aircraft model designations as it appears on the manufacturer's application, including use of hyphens or decimal points, should match what is stamped on the aircraft's data or nameplate. What the manufacturer chooses to call an aircraft for marketing or promotional purposes is irrelevant to the airworthiness authorities; the first amendment to the DC-9 type certificate for the new MD-80 aircraft was applied as DC-9-81, which approved on August 26, 1980. All MD-80 models have since been approved under additional amendments to the DC-9 type certificate. In 1983, McDonnell Douglas decided that the DC-9-80 would be designated the MD-80. Instead of using the MD- prefix as a marketing symbol, an application was made to again amend the type certificate to include the MD-81, MD-82, MD-83.
This change was dated March 10, 1986, the type certificate declared that although the MD designator could be used in parentheses, it must be accompanied by the official designation, for example: DC-9-81. All Long Beach aircraft in the MD-80 series thereafter had MD-81, MD-82, or MD-83 stamped on the aircraft nameplate. Although not certified until October 21, 1987, McDonnell Douglas had applied for models DC-9-87 and DC-9-87F on February 14, 1985; the third derivative was officially designated DC-9-87, although no nameplates were stamped DC-9-87. For the MD-88, an application for a type certificate model amendment was made after the earlier changes, so there was not a DC-9-88, certified on December 8, 1987; the FAA's online aircraft registry database shows the DC-9-88 and DC-9-80 designations in existence but unused. The second generation was produced on a common line with the first generation DC-9s, with which it shares its line number sequence. After the delivery of 976 DC-9s and 108 MD-80s, McDonnell Douglas stopped DC-9 production.
Hence, commencing with the 1,085th DC-9/MD-80 delivery, an MD-82 for VIASA in December 1982, all DC-9s produced were Series 80s/MD-80s. In 1985, McDonnell Douglas, after years of negotiating attributed to Gareth C. C. Chang, president of a M
O'Hare International Airport
O'Hare International Airport referred to as O'Hare Airport, Chicago O'Hare, or O'Hare, is an international airport located on the far Northwest Side of Chicago, Illinois, 14 miles northwest of the Loop business district, operated by the Chicago Department of Aviation and covering 7,627 acres. O'Hare has non-stop flights to 228 destinations in North America, South America, Africa and Oceania. Established to be the successor to Chicago’s "busiest square mile in the world", Midway Airport, O'Hare began as an airfield serving a Douglas manufacturing plant for C-54 military transports during World War II, it was named for Edward "Butch" O'Hare, the U. S. Navy's first Medal of Honor recipient during that war. At the height of the Cold War, O'Hare served as an active fighter base for the Air Force; as the first major airport planned post-war, O’Hare's innovative design pioneered concepts such as concourses, direct highway access to the terminal, jet bridges, underground refueling systems. It became famous as the first World’s Busiest Airport of the jet age, holding that distinction from 1963 to 1998.
O'Hare is unusual in that it serves a major hub for more than one of the three U. S. mainline carriers. It is a focus city for Frontier Airlines and Spirit Airlines. While Terminals 2 and 3 remain of the original design, the airport has been engaged in a massive modernization of the airfield, is beginning an expansion of passenger facilities that will remake it as North America’s first airport built around airline alliances. Not long after the opening of Midway Airport in 1926, the City of Chicago realized that additional airport capacity would be needed in the future; the city government investigated various potential airport sites during the 1930s, but made little progress prior to America's entry into World War II. O'Hare's place in aviation began with a manufacturing plant for Douglas C-54s during WWII; the site was known as Orchard Place, had been a small German farming community. The 2,000,000 square feet plant, located in the northeast corner of what is now the airport property, needed easy access to the workforce of the nation's second-largest city, as well as its extensive railroad infrastructure and location far from enemy threat.
Some 655 C-54s were built at the plant. The attached airfield, from which the completed planes were flown out, was known as Douglas Airport. Less known is the fact that it was the location of the Army Air Force’s 803rd Specialized Depot, a unit charged with storing many captured enemy aircraft. A few representatives of this collection would be transferred to the Smithsonian Institution's National Air and Space Museum. Douglas Company's contract ended in 1945 and, though consideration was given to building commercial aircraft at Orchard, the company chose to concentrate commercial production at its original headquarters in Santa Monica, CA. With the departure of Douglas, the complex took the name of Orchard Field Airport, was assigned the IATA code ORD; the United States Air Force used the field extensively during the Korean War, at which time there was still no scheduled commercial service at the airport. Although not its primary base in the area, the Air Force used O'Hare as an active fighter base.
By 1960, the need for O'Hare as an active duty fighter base was diminishing, just as commercial business was picking up at the airport. The Air Force removed active-duty units from O'Hare and turned the station over to Continental Air Command, enabling them to base reserve and Air National Guard units there; as a result of a 1993 agreement between the City and the Department of Defense, the reserve based was closed on April 1, 1997, ending its career as the home of the 928th Airlift Wing. At that time, the 357 acre site came under the ownership of the Chicago Department of Aviation. In 1945, Chicago mayor Edward Kelly established a formal board to choose the site of a new facility to meet future aviation demands. After considering various proposals, the board decided upon the Orchard Field site, acquired most of the federal government property in March 1946; the military retained a small parcel of property on the site, the rights to use 25% of the airfield's operating capacity for free. Ralph H. Burke devised an airport master plan based on the pioneering idea of what he called "split finger terminals", allowing a terminal building to be attached to "airline wings", each providing space for gates and planes.
Other innovations Burke brought to the O'Hare design included underground refueling, direct highway access to the front of terminals, direct rail access, all of which are utilized at airports worldwide today. O'Hare was the site of the world's first jet bridge in 1958, adapted slip form paving, developed for the nation's new Interstate highway system, for seamless concrete runways. In 1949, the City renamed the facility O'Hare Field to honor Edward "Butch" O'Hare, the U. S. Navy's first flying ace and Medal of Honor recipient in World War II, its IATA code remained unchanged, resulting in O'Hare's being one of the few IATA codes bearing no connection to the airport's name or metropolitan area. Scheduled passenger service began in 1955. Although Chicago h
Ontario is one of the 13 provinces and territories of Canada and is located in east-central Canada. It is Canada's most populous province accounting for 38.3 percent of the country's population, is the second-largest province in total area. Ontario is fourth-largest jurisdiction in total area when the territories of the Northwest Territories and Nunavut are included, it is home to the nation's capital city and the nation's most populous city, Ontario's provincial capital. Ontario is bordered by the province of Manitoba to the west, Hudson Bay and James Bay to the north, Quebec to the east and northeast, to the south by the U. S. states of Minnesota, Ohio and New York. All of Ontario's 2,700 km border with the United States follows inland waterways: from the west at Lake of the Woods, eastward along the major rivers and lakes of the Great Lakes/Saint Lawrence River drainage system; these are the Rainy River, the Pigeon River, Lake Superior, the St. Marys River, Lake Huron, the St. Clair River, Lake St. Clair, the Detroit River, Lake Erie, the Niagara River, Lake Ontario and along the St. Lawrence River from Kingston, Ontario, to the Quebec boundary just east of Cornwall, Ontario.
There is only about 1 km of land border made up of portages including Height of Land Portage on the Minnesota border. Ontario is sometimes conceptually divided into Northern Ontario and Southern Ontario; the great majority of Ontario's population and arable land is in the south. In contrast, the larger, northern part of Ontario is sparsely populated with cold winters and heavy forestation; the province is named after Lake Ontario, a term thought to be derived from Ontarí:io, a Huron word meaning "great lake", or skanadario, which means "beautiful water" in the Iroquoian languages. Ontario has about 250,000 freshwater lakes; the province consists of three main geographical regions: The thinly populated Canadian Shield in the northwestern and central portions, which comprises over half the land area of Ontario. Although this area does not support agriculture, it is rich in minerals and in part covered by the Central and Midwestern Canadian Shield forests, studded with lakes and rivers. Northern Ontario is subdivided into two sub-regions: Northeastern Ontario.
The unpopulated Hudson Bay Lowlands in the extreme north and northeast swampy and sparsely forested. Southern Ontario, further sub-divided into four regions. Despite the absence of any mountainous terrain in the province, there are large areas of uplands within the Canadian Shield which traverses the province from northwest to southeast and above the Niagara Escarpment which crosses the south; the highest point is Ishpatina Ridge at 693 metres above sea level in Temagami, Northeastern Ontario. In the south, elevations of over 500 m are surpassed near Collingwood, above the Blue Mountains in the Dundalk Highlands and in hilltops near the Madawaska River in Renfrew County; the Carolinian forest zone covers most of the southwestern region of the province. The temperate and fertile Great Lakes-Saint Lawrence Valley in the south is part of the Eastern Great Lakes lowland forests ecoregion where the forest has now been replaced by agriculture and urban development. A well-known geographic feature is part of the Niagara Escarpment.
The Saint Lawrence Seaway allows navigation to and from the Atlantic Ocean as far inland as Thunder Bay in Northwestern Ontario. Northern Ontario occupies 87 percent of the surface area of the province. Point Pelee is a peninsula of Lake Erie in southwestern Ontario, the southernmost extent of Canada's mainland. Pelee Island and Middle Island in Lake Erie extend farther. All are south of 42°N – farther south than the northern border of California; the climate of Ontario varies by location. It is affected by three air sources: cold, arctic air from the north; the effects of these major air masses on temperature and precipitation depend on latitude, proximity to major bodies of water and to a small extent, terrain relief. In general, most of Ontario's climate is classified as humid continental. Ontario has three main climatic regions; the surrounding Great Lakes influence the climatic region of southern Ontario. During the fall and winter months, heat stored from the lakes is released, moderating the climate near the shores of the lakes.
This gives some parts of southern Ontario milder winters than mid-continental areas at lower latitudes. Parts of Southwestern Ontario have a moderate humid continental climate, similar to that of the inland Mid-Atlantic states and the Great Lakes portion of the Midwestern United States; the region has warm to cold winters. Annual precipitation is well distributed throughout the year. Most of this region lies in the lee of the Great Lakes. In December 2010, the snowbelt set a new record when it was h
The Boeing 727 is an American midsized, narrow-body three-engined jet aircraft built by Boeing Commercial Airplanes from the early 1960s to 1984. It can carry 149 to 189 passengers and models can fly up to 2,700 nautical miles nonstop. Intended for short and medium-length flights, the 727 can use short runways at smaller airports, it has three Pratt & Whitney JT8D engines below the T-tail, one on each side of the rear fuselage with a center engine that connects through an S-duct to an inlet at the base of the fin. The 727 is the only Boeing trijet, as a commercial design entering production; the 727 followed the 707, a quad-jet airliner, with which it shares its upper fuselage cross-section and cockpit design. The 727-100 first flew in February 1963 and entered service with Eastern Air Lines in February 1964; the 727 became a mainstay of airlines' domestic route networks and was used on short- and medium-range international routes. Passenger and convertible versions of the 727 were built; the highest production rate of the 727 was in the 1970s.
As of July 2018, a total of 44 Boeing 727s were in commercial service with 23 airlines, plus a few more in government and private use. Airport noise regulations have led to 727s being equipped with hush kits. Since 1964, there have been 118 fatal incidents involving the Boeing 727. Successor models include variants of the 737 and the 757-200; the last commercial passenger flight of the type was in January 2019. The Boeing 727 design was a compromise among United Airlines, American Airlines, Eastern Air Lines. United Airlines requested a four-engine aircraft for its flights to high-altitude airports its hub at Stapleton International Airport in Denver, Colorado. American Airlines, operating the four-engined Boeing 707 and Boeing 720, requested a twin-engined aircraft for efficiency. Eastern Airlines wanted a third engine for its overwater flights to the Caribbean, since at that time twin-engine commercial flights were limited by regulations to routes with 60-minute maximum flying time to an airport.
The three airlines agreed on a trijet design for the new aircraft. In 1959, Lord Douglas, chairman of British European Airways, suggested that Boeing and de Havilland Aircraft Company work together on their trijet designs, the 727 and D. H.121 Trident, respectively. The two designs had a similar layout, the 727 being larger. At that time Boeing intended to use three Allison AR963 turbofan engines, license-built versions of the Rolls-Royce RB163 Spey used by the Trident. Boeing and de Havilland each sent engineers to the other company's locations to evaluate each other's designs, but Boeing decided against the joint venture. De Havilland had wanted Boeing to license-build the D. H.121, while Boeing felt that the aircraft needed to be designed for the American market, with six-abreast seating and the ability to use runways as short as 4,500 feet. In 1960, Pratt & Whitney was looking for a customer for its new JT8D turbofan design study, based on its J52 turbojet, while United and Eastern were interested in a Pratt & Whitney alternative to the RB163 Spey.
Once Pratt & Whitney agreed to go ahead with development of the JT8D, Eddie Rickenbacker, chairman of the board of Eastern, told Boeing that the airline preferred the JT8D for its 727s. Boeing had not offered the JT8D, as it was about 1,000 lb heavier than the RB163, though more powerful. Boeing reluctantly agreed to offer the JT8D as an option on the 727, it became the sole powerplant. With high-lift devices on its wing, the 727 could use shorter runways than most earlier jets. 727 models were stretched to carry more passengers and replaced earlier jet airliners such as the Boeing 707 and Douglas DC-8, as well as aging propeller airliners such as the DC-4, DC-6, DC-7, the Lockheed Constellations on short- and medium-haul routes. For over a decade, more 727s were built per year than any other jet airliner; the airliner's middle engine at the rear of the fuselage gets air from an inlet ahead of the vertical fin through an S-shaped duct. This S-duct proved to be troublesome in that flow distortion in the duct induced a surge in the centerline engine on the take-off of the first flight of the 727-100.
This was fixed by the addition of several large vortex generators in the inside of the first bend of the duct. The 727 was designed for smaller airports, so independence from ground facilities was an important requirement; this led to one of the 727's most distinctive features: the built-in airstair that opens from the rear underbelly of the fuselage, which could be opened in flight. Hijacker D. B. Cooper used this hatch when he parachuted from the back of a 727, as it was flying over the Pacific Northwest. Boeing subsequently modified the design with the Cooper vane so that the airstair could not be lowered in flight. Another innovation was the auxiliary power unit, which allowed electrical and air-conditioning systems to run independently of a ground-based power supply, without having to start one of the main engines. An unusual design feature is that the APU is mounted in a hole in the keel beam web, in the main landing gear bay; the 727 is eq
McDonnell Douglas DC-9
The McDonnell Douglas DC-9 is a twin-engine, single-aisle jet airliner. It first flew and entered airline service in 1965; the DC-9 was designed for short flights. The final DC-9 was delivered in October 1982. DC-9-based airliners including the MD-80, MD-90 and Boeing 717 followed in production. With the final deliveries of the 717 in 2006, production of the DC-9/MD-80/90/717 aircraft family ceased after 41 years and 2441 units built. During the 1950s Douglas Aircraft studied a short- to medium-range airliner to complement their higher capacity, long range DC-8. A medium-range four-engine Model 2067 was studied but it did not receive enough interest from airlines and it was abandoned. In 1960, Douglas signed a two-year contract with Sud Aviation for technical cooperation. Douglas would market and support the Sud Aviation Caravelle and produce a licensed version if airlines ordered large numbers. None were ordered and Douglas returned to its design studies after the cooperation deal expired. In 1962, design studies were underway.
The first version had a gross weight of 69,000 lb. This design was changed into. Douglas gave approval to produce the DC-9 on April 8, 1963. Unlike the competing but larger Boeing 727 trijet, which used as many 707 components as possible, the DC-9 was an all-new design; the DC-9 has two rear-mounted Pratt & Whitney JT8D turbofan engines small, efficient wings, a T-tail. The DC-9's takeoff weight was limited to 80,000 lb for a two-person flight crew by Federal Aviation Agency regulations at the time. DC-9 aircraft have five seats across for economy seating; the airplane seats 80 to 135 passengers depending on seating arrangement. The DC-9 was designed for short to medium routes to smaller airports with shorter runways and less ground infrastructure than the major airports being served by larger designs like the Boeing 707 and Douglas DC-8. Accessibility and short field characteristics were called for. Turnarounds were simplified by built-in airstairs, including one in the tail, which shortened boarding and deplaning times.
The tail-mounted engine design facilitated a clean wing without engine pods, which had numerous advantages. For example, flaps could be longer, unimpeded by pods on the leading edge and engine blast concerns on the trailing edge; this simplified design improved airflow at low speeds and enabled lower takeoff and approach speeds, thus lowering field length requirements and keeping wing structure light. The second advantage of the tail-mounted engines was the reduction in foreign object damage from ingested debris from runways and aprons. However, with this position, the engines could ingest ice streaming off the wing roots. Third, the absence of engines in underslung pods allowed a reduction in fuselage ground clearance, making the aircraft more accessible to baggage handlers and passengers; the problem of deep stalling, revealed by the loss of the BAC One-Eleven prototype in 1963, was overcome through various changes, including the introduction of vortilons, small surfaces beneath the wing's leading edge used to control airflow and increase low speed lift.
The first DC-9, a production model, flew on February 25, 1965. The second DC-9 flew a few weeks with a test fleet of five aircraft flying by July; this allowed the initial Series 10 to gain airworthiness certification on November 23, 1965, to enter service with Delta Air Lines on December 8. The DC-9 was always intended to be available in multiple versions to suit customer requirements, The first stretched version, the Series 30, with a longer fuselage and extended wing tips, flew on August 1, 1966, entering service with Eastern Air Lines in 1967; the initial Series 10 would be followed by the improved -20, -30, -40 variants. The final DC-9 series was the -50, which first flew in 1974; the DC-9 was a commercial success with 976 built when production ended in 1982. The DC-9 is one of the longest-lasting aircraft in operation, its last successor, the Boeing 717, was produced until 2006. The DC-9 family was produced in 2441 units: 1191 MD-80s, 116 MD-90s and 155 Boeing 717s; this compares to 8,000 Airbus A320s delivered as of February 2018 and 10,000 Boeing 737s completed as of March 2018.
Studies aimed at further improving DC-9 fuel efficiency, by means of retrofitted wingtips of various types, were undertaken by McDonnell Douglas. However, these did not demonstrate significant benefits with existing fleets shrinking; the wing design makes retrofitting difficult. The DC-9 was followed by the introduction of the MD-80 series in 1980; this was called the DC-9-80 series. It was a lengthened DC-9-50 with a higher maximum takeoff weight, a larger wing, new main landing gear, higher fuel capacity; the MD-80 series features a number of variants of the Pratt & Whitney JT8D turbofan engine having higher thrust ratings than those available on the DC-9. The series includes the MD-81, MD-82, MD-83, MD-88, shorter fuselage MD-87; the MD-80 series was further developed into the McDonnell Douglas MD-90 in the early 1990s. It has yet another fuselage stretch, an electronic flight instrument system, new International Aero V2500 high-bypass turbofan engines. In comparison to the successful MD-80 few MD-90s were built.
The final variant was the MD-95, renamed the Boeing 717-200 after McDonnell Douglas's merger with Boeing in 1997 and before aircraft deliveries began. The fuselage length and wing are similar to those of the DC-9-30, but much use was made of lighter, modern materials. Power is supplied by two BMW/Rolls-Royce BR715 high-bypass turbofan en