Boeing 727: История и характеристики узкофюзеляжного авиалайнера

Narrow body jet airliner

type = Narrow body jet airliner national origin = United States manufacturer = Boeing Commercial Airplanes designer = first flight = February 9, 1963 introduced = February 1, 1964, with Eastern Air Lines status = In cargo and executive service

The Boeing 727 is an American narrow body airliner that was developed and produced by Boeing Commercial Airplanes. After the heavier 707 quad jet was introduced in 1958, Boeing addressed the demand for shorter flight lengths from smaller airports. On December 5, 1960, the 727 was launched with 40 orders each from United Airlines and Eastern Air Lines. The first 727 100 rolled out on November 27, 1962, first flew on February 9, 1963, and entered service with Eastern on February 1, 1964. The only trijet aircraft to be produced by Boeing, the 727 is powered by Pratt & Whitney JT8D low bypass turbofans below a T tail, one on each side of the rear fuselage and a center one fed through an S duct. It shares its six abreast upper fuselage cross section and cockpit with the 707 that was also later used on the 737. The 133 feet (41 m) 727 100 typically carries 106 passengers in two classes over , or 129 in a single class. Launched in 1965, the stretched 727 200 flew in July 1967 and entered service with Northeast Airlines that December. The 6.10 m longer variant typically carries 134 passengers in two classes over , or 155 in a single class. A freighter and a “Quick Change” convertible version were also offered. The 727 was used for domestic flights and on international flights within its range. Airport noise regulations have led to hush kit installations. Its last commercial passenger flight was in January 2019. It was succeeded by the 757 and larger variants of the 737. There have been 353 incidents involving the Boeing 727. Production ended in September 1984 with 1,832 having been built.

The airliner's middle engine (engine 2) at the very 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 initially could be opened in flight. The design included an auxiliary power unit (APU), which allowed electrical and air conditioning systems to run independently of a ground based power supply, and 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 proved to be such a reliable and versatile airliner that it came to form the core of many startup airlines' fleets. The 727 was successful with airlines worldwide partly because it could use smaller runways while still flying medium range routes. This allowed airlines to carry passengers from cities with large populations, but smaller airports to worldwide tourist destinations. One of the features that gave the 727 its ability to land on shorter runways was its clean wing design. Fowler flaps) could be used on the entire wing. Together, these high lift devices produced a maximum wing lift coefficient of 3.0 (based on the flap retracted wing area). These carriers' Pilots' Operation Handbooks disallowed using more than 30° of flaps on the 727, even going so far as installing plates on the flap lever slot to prevent selection of more than 30° of flaps.

The 727 is one of the noisiest commercial jetliners, categorized as Stage 2 by the U. S. Noise Control Act of 1972, which mandated the gradual introduction of quieter Stage 3 aircraft. The 727's JT8D jet engines use older low bypass turbofan technology, whereas Stage 3 aircraft use the more efficient and quieter high bypass turbofan design. When the Stage 3 requirement was being proposed, Boeing engineers analyzed the possibility of incorporating quieter engines on the 727. They determined that the JT8D 200 engine could be used on the two side mounted pylons. The JT8D 200 engines are much quieter than the original JT8D 1 through 17 variant engines that power the 727, as well as more fuel efficient due to the higher bypass ratio, but the structural changes to fit the larger diameter engine ( fan diameter in the JT8D 200 compared to in the JT8D 1 through 17) into the fuselage at the number two engine location were prohibitive. Current regulations require that a 727, or any other Stage 2 noise jetliner in commercial service must be retrofitted with a hush kit to reduce engine noise to Stage 3 levels to continue to fly in U. S. airspace. These regulations have been in effect since December 31, 1999. One such hush kit is offered by FedEx, and has been purchased by over 60 customers. Aftermarket winglet kits, originally developed by Valsan Partners and later marketed by Quiet Wing Corp. have been installed on many 727s to reduce noise at lower speeds, as well as to reduce fuel consumption. In addition, Raisbeck Engineering developed packages to enable 727s to meet the Stage 3 noise requirements. These packages managed to get light and medium weight 727s to meet Stage 3 with simple changes to the flap and slat schedules. For heavier weight 727s, exhaust mixers must be added to meet Stage 3. Since September 1, 2010, 727 jetliners (including those with a hush kit) are banned from some Australian airports because they are too loud.

In addition to domestic flights of medium range, the 727 was popular with international passenger airlines. The 727s were the backbone of its fleet until the 2000s; FedEx began replacing them with Boeing 757s in 2007. The 727 has proven to be popular where the airline serves airports with gravel, or otherwise lightly improved, runways. The Canadian airline First Air, for example, previously used a 727 100C to serve the communities of Resolute Bay and Arctic Bay in Nunavut, whose Resolute Bay Airport and former Nanisivik Airport both have gravel runways. The high mounted engines greatly reduce the risk of foreign object damage. A military version, the Boeing C 22, was operated as a medium range transport aircraft by the Air National Guard and National Guard Bureau to airlift personnel. A total of three C 22Bs were in use, all assigned to the 201st Airlift Squadron, District of Columbia Air National Guard. At the start of the 21st century, the 727 remained in service with a few large airlines. Faced with higher fuel costs, lower passenger volumes due to the post 9/11 economic climate, increasing restrictions on airport noise, and the extra expenses of maintaining older planes and paying flight engineers' salaries, most major airlines phased out their 727s; they were replaced by twin engined aircraft, which are quieter and more fuel efficient. Modern airliners also have a smaller flight deck crew of two pilots, while the 727 required two pilots and a flight engineer. Delta Air Lines, the last major U. S. carrier to do so, retired its last 727 from scheduled service in April 2003. Northwest Airlines retired its last 727 from charter service in June 2003. Many airlines replaced their 727s with either the 737 800 or the Airbus A320; both are close in size to the 727 200. as of 2013, a total of 109 Boeing 727s were in commercial service with 34 airlines; three years later, the total had fallen to 64 airframes in service with 26 airlines. On March 2, 2016, the first 727 produced (N7001U), which first flew on February 9, 1963, made a flight to a museum after extensive restoration. The 727 100 had carried about three million passengers during its years of service. Originally a prototype, it was later sold to United Airlines, which donated it to the Museum of Flight in Seattle in 1991. The jet was restored over 25 years by the museum and was ferried from Paine Field in Everett, Washington to Boeing Field in Seattle, where it was put on permanent display at the Aviation Pavilion. The Federal Aviation Administration granted the museum a special permit for the 15 minute flight. The museum's previous 727 223, tail number N874AA, was donated to the National Airline History Museum in Kansas City and was planned to be flown to its new home once FAA ferry approval was granted. After a series of financial problems with the restoration, N874AA was seized by Boeing Field for nonpayment of storage fees in 2021 and subsequently broken up and scrapped. Iran Aseman Airlines, the last passenger airline operator, made the worldwide last scheduled 727 passenger flight on January 13, 2019 between Zahedan and Tehran.

+ Boeing 727 Characteristics Variant 727 100 727 200 727 200 Advanced Flight crew Three Two class seats 106: 16F@38", 90Y@34" 134: 20F@38", 114Y@34" One class seats 125@34" 155@34" Exit limit , 32° sweep MTOW 169,000 lb (76,700 kg) 172,000 lb (78,100 kg) 209,500 lb (95,100 kg) OEW 87,696 lb (39,800 kg) 97,650 lb (44,330 kg) 100,700 lb (45,720 kg) Fuel capacity 7,680 US gal (29,069 L) 8,090 US gal (30,620 L) 10,585 US gal (40,060 L) Engines ×3 Pratt & Whitney JT8D 1/7/9 JT8D 7/9/11 JT8D 9/15/17/17R Thrust ×3 Range Take off 3078.48 m MMO 467–515 kn (865–953 km/h; ) Ceiling