Misplaced Pages

#160839

60-592: The British Aerospace 125 is a twinjet mid-size business jet . Originally developed by de Havilland and initially designated as the DH.125 Jet Dragon , it entered production as the Hawker Siddeley HS.125 , which was the designation used until 1977. Later on, more recent variants of the type were marketed as the Hawker 800 . More than 60% of the total sales of the aircraft were to North American customers. It

120-649: A great circle route. Hence, in case of an engine failure in a twinjet (like Boeing 777 ), the twin-jet could make emergency landings in fields in Canada , Alaska , eastern Russia , Greenland , Iceland , or the British Isles . The Boeing 777 has also been approved by the Federal Aviation Administration for flights between North America and Hawaii , which is the world's longest regular airline route with no diversion airports along

180-518: A podded engine usually mounted beneath, or occasionally above or within, each wing. Most notable examples of such a configuration are the Boeing 737 and Airbus A320 . The second has one engine mounted on each side of the rear fuselage, close to its empennage , used by many business jets , although some airliners like the Fokker 70 , Douglas DC-9 and COMAC ARJ21 utilise such a design as well. In

240-525: A 3 feet (0.91 m) wide cabin door also allowed the loading of bulky equipment, which was seen as particularly attractive to military operators. However, the internal "up and over" door was replaced on the Series 400 and thereafter by a more usual outward opening door with built-in steps. An emergency overwing exit hatch is located in the passenger cabin midsection over the starboard wing (although some versions have both port and starboard exits). The rear of

300-419: A British Aerospace 125-800 transporting Botswana President Quett Masire was struck by a missile launched by a nearby Angolan Mig-23 , apparently inadvertently. While badly damaged by the direct hit (which resulted in the loss of an engine, decompression of the cabin, and rupture of its fuel tanks) the aircraft was successfully landed by BAe demonstrator pilot Arthur Ricketts. It was later rebuilt. In 2013,

360-412: A high degree of passenger comfort. In an executive configuration, the flight deck is separated from the main passenger cabin; the single entrance of the aircraft, located directly behind the cockpit and forward of the passenger cabin, forms a vestibule area in which luggage can be stored and meals prepared during flight. An unobstructed cabin floor with 5 feet 9 inches (1.75 m) of headroom and

420-627: A light aircraft, the configuration is significant because it offers superior visibility to the pilot. On light aircraft, shoulder-wings tend to be mounted further aft than a high wing, and so may need to be swept forward to maintain correct center of gravity . Examples of light aircraft with shoulder wings include the ARV Super2 , the Bölkow Junior , Saab Safari and the Barber Snark . A high wing has its upper surface on or above

480-407: A pendulous fuselage which requires no wing dihedral for stability; and, by comparison with a low-wing, a shoulder-wing's limited ground effect reduces float on landing. Compared to a low-wing, shoulder-wing and high-wing configurations give increased propeller clearance on multi-engined aircraft. On a large aircraft, there is little practical difference between a shoulder wing and a high wing; but on

540-470: A popular configuration for amphibians and small homebuilt and ultralight aircraft . Although the first successful aircraft were biplanes, the first attempts at heavier-than-air flying machines were monoplanes, and many pioneers continued to develop monoplane designs. For example, the first aeroplane to be put into production was the 1907 Santos-Dumont Demoiselle , while the Blériot XI flew across

600-408: A specified distance from an available diversion airport. Overwater flights near diversion airports need not be ETOPS/LROPS-compliant. Since the 1990s, airlines have increasingly turned from four-engine or three-engine airliners to twin-engine airliners to operate transatlantic and transpacific flight routes. On a nonstop flight from America to Asia or Europe, the long-range aircraft usually follows

660-541: A trijet aircraft) and Boeing worked on new widebody twinjet designs that would become the Airbus A330 and Boeing 777 , respectively. The MD-11's long range advantage was brief as it was soon nullified by the Airbus A330-300 and the extended-range Boeing 767-300ER and Boeing 777-200ER. The Airbus A320 twinjet stands out as the most produced jet airliner. The Boeing 777X is the world's largest twinjet, and

SECTION 10

#1732783938161

720-489: A wing of a given size, the weight reduction allows it to fly slower and with a lower-powered and more economical engine. For this reason, all monoplane wings in the pioneer era were braced and most were up until the early 1930s. However, the exposed struts or wires create additional drag, lowering aerodynamic efficiency and reducing the maximum speed. High-speed and long-range designs tend to be pure cantilevers, while low-speed short-range types are often given bracing. Besides

780-432: Is a fixed-wing aircraft configuration with a single mainplane, in contrast to a biplane or other types of multiplanes , which have multiple planes. A monoplane has inherently the highest efficiency and lowest drag of any wing configuration and is the simplest to build. However, during the early years of flight, these advantages were offset by its greater weight and lower manoeuvrability, making it relatively rare until

840-487: Is equipped with a de-icing system, which uses a mixture of bleed air from the engines, TKS fluid for general airframe, and AC electric windshield heating to prevent ice formation. Weather radar was incorporated into the aircraft's avionics. The Royal Air Force equipped some of their aircraft with equipment to defend against attack by infra-red missiles. The pressurised fuselage was designed to accommodate two pilots and six passengers. Various interiors were offered, with

900-474: Is not an issue, as one of the engines is more than powerful enough to keep the aircraft aloft (see below). Mostly, ETOPS certification involves maintenance and design requirements ensuring that a failure of one engine cannot make the other one fail also. The engines and related systems need to be independent and (in essence) independently maintained. ETOPS/LROPS is often incorrectly thought to apply only to long overwater flights, but it applies to any flight more than

960-410: Is that the fuselage is closer to the ground which eases cargo loading, especially for aircraft with a rear-fuselage cargo door. Military cargo aircraft are predominantly high-wing designs with a rear cargo door. A parasol wing is not directly attached to the fuselage but held above it, supported by either cabane struts or a pylon. Additional bracing may be provided by struts or wires extending from

1020-518: The 777X in November 2013, while then-CEO Fabrice Brégier preferred to focus on product improvement rather than all-new concepts for 10 years. It would have a 10-abreast economy like the 777; its 565 m (6,081 sq ft) wing, slightly more than the 747-8, would have an 80 m (262 ft) span, as wide as the A380 , for a 892,900 lb (405 t) MTOW compared to 775,000 lb (352 t) for

1080-399: The Boeing 777 , Boeing 787 and Airbus A350 have matched or surpassed older quad-jet designs such as the Boeing 747 and Airbus A340 in these aspects, and twinjets have been more successful in terms of sales than quad-jets. In 2012, Airbus studied a 470-seat twinjet competitor for the Boeing 747-8 with lower operating costs expected between 2023 and 2030, revived after Boeing launched

1140-590: The British Royal Family . In the later stages of the War in Afghanistan , various 125s were used to transport military officers and other key personnel in and out of the country. The type was scheduled to be withdrawn from RAF service by 2022, but was withdrawn in 2015. By the early 1990s, British Aerospace, the manufacturer of the type at this point, had two main variants of the aircraft in production;

1200-571: The English Channel in 1909. Throughout 1909–1910, Hubert Latham set multiple altitude records in his Antoinette IV monoplane, eventually reaching 1,384 m (4,541 ft). The equivalent German language term is Eindecker , as in the mid-wing Fokker Eindecker fighter of 1915 which for a time dominated the skies in what became known as the " Fokker scourge ". The German military Idflieg aircraft designation system prior to 1918 prefixed monoplane type designations with an E , until

1260-641: The Fokker D.VIII and Morane-Saulnier AI in the later part of the First World War. A parasol wing also provides a high mounting point for engines and during the interwar period was popular on flying boats, which need to lift the propellers clear of spray. Examples include the Martin M-130 , Dornier Do 18 and the Consolidated PBY Catalina . Compared to a biplane , a parasol wing has less bracing and lower drag. It remains

SECTION 20

#1732783938161

1320-744: The Gulfstream IV and Falcon 900 . The Royal Air Force was a significant early operator of the type, receiving 20 aircraft equipped as a navigation trainer and designated Hawker Siddeley Dominie T.1 . The type entered service in 1965, with the surviving aircraft upgraded in 1996 to be more suitable for training crews for modern aircraft, with a new radar fitted. The Dominie served in excess of 45 years before being retired in 2011 due to diminishing requirements. Additional 125s were acquired and operated by No. 32 Squadron RAF as communications and light transport aircraft; these were also occasionally operated to transport Queen Elizabeth II and other members of

1380-451: The braced parasol wing became popular on fighter aircraft, although few arrived in time to see combat. It remained popular throughout the 1920s. On flying boats with a shallow hull, a parasol wing allows the engines to be mounted above the spray from the water when taking off and landing. This arrangement was popular on flying boats during the 1930s; a late example being the Consolidated PBY Catalina . It died out when taller hulls became

1440-594: The 125 series is the most successful British commercial aircraft ever built, and the world's longest in-production business jet". Production of the aircraft came to an abrupt halt in 2013 due to the bankruptcy of owner Hawker Beechcraft , who has suffered during the Great Recession of the late 2000s in which demand for business jets had slumped for a number of years. The type had been in production for more than 50 years when manufacturing stopped, during which time over 1,600 aircraft had been produced. In April 2013,

1500-725: The 1930s, the cantilever monoplane was fast becoming the standard configuration for a fixed-wing aircraft. Advanced monoplane fighter-aircraft designs were mass-produced for military services around the world in both the Soviet Union and the United States in the early–mid 1930s, with the Polikarpov I-16 and the Boeing P-26 Peashooter respectively. Most military aircraft of WWII were monoplanes, as have been virtually all aircraft since, except for

1560-457: The 1930s. Since then, the monoplane has been the most common form for a fixed-wing aircraft. The inherent efficiency of the monoplane is best achieved in the cantilever wing, which carries all structural forces internally. However, to fly at practical speeds the wing must be made thin, which requires a heavy structure to make it strong and stiff enough. External bracing can be used to improve structural efficiency, reducing weight and cost. For

1620-753: The 777-200LR variant has the world's second longest aircraft range (behind Airbus A350-900 ULR). Other Boeing twinjets include the 767 , 757 (With the latter having stopped production, but still in commercial service) and 787 . Competitor Airbus produces the A320 family , the A330 , and the A350 . Some modern commercial airplanes still use four engines ( quad-jets ) like the Airbus A380 and Boeing 747-8 , which are classified as very large aircraft (over 400 seats in mixed-class configurations). Four engines are still used on

1680-432: The 777X, with a composite structure for an operating empty weight of 467,400 lb (212 t), and a 8,150 nmi (15,090 km) range at Mach 0.85. When flying far from diversionary airports (so called ETOPS/LROPS flights), the aircraft must be able to reach an alternate on the remaining engine within a specified time in case of one engine failure. When aircraft are certified according to ETOPS standards, thrust

1740-969: The FAA modified its rules to prohibit the operation of jets weighing 75,000 pounds (34,000 kg) or less that are not stage 3 noise compliant, specifically mentioning the 125 series of aircraft. This required any aircraft of the type either to have compliant engines installed, or to be fitted with a hush kit , to fly over most of the United States after 31 December 2015. Private operators, air taxi, shared ownership and corporate charter operators worldwide. Between 1965 and 1972 Qantas used two Series 3s for crew training. Data from Jane's All The World's Aircraft 1976–77, General characteristics Performance Maximum Operating Mach number (M MO Related development Aircraft of comparable role, configuration, and era Related lists Twinjet There are three common configurations of twinjet aircraft. The first, common on large aircraft such as airliners, has

1800-481: The aircraft more manoeuvrable, as on the Spitfire ; but aircraft that value stability over manoeuvrability may then need some dihedral . A feature of the low-wing position is its significant ground effect , giving the plane a tendency to float farther before landing. Conversely, this ground effect permits shorter takeoffs. A mid wing is mounted midway up the fuselage. The carry-through spar structure can reduce

1860-452: The aircraft systems so in the event of a single engine failure, all aircraft systems continue to operate normally. All control surfaces of the aircraft are aerodynamically balanced using set-back hinges and geared tabs. The flaps and airbrakes are operated hydraulically, while the ailerons, elevators, and rudder are manually operated. The design of the control circuits allows for a Collins-built A.P.103 autopilot to be incorporated. The aircraft

British Aerospace 125 - Misplaced Pages Continue

1920-531: The aircraft were still being assembled and partially equipped in the Broughton site, now being owned and managed by Airbus UK ; various sub-assemblies were also produced in Airbus UK's Buckley facility. From 1996 onwards, the assembled sections and components were shipped to Wichita, Kansas in the United States, to undergo final assembly. Writing in 1993, Flying Magazine said of the type "In numerical terms,

1980-506: The aircraft's customers have been located in North America; in 1990, out of the 650 aircraft then being operated, more than 400 were being flown in the United States. Reportedly, one aircraft was being sold every seven working days for a substantial period of the type's production life. Successively larger versions were introduced to extend the type's appeal and to better compete against larger jets being used for business travel, such as

2040-525: The approval of the Fokker D.VIII fighter from its former "E.V" designation. However, the success of the Fokker was short-lived, and World War I was dominated by biplanes. Towards the end of the war, the parasol monoplane became popular and successful designs were produced into the 1920s. Nonetheless, relatively few monoplane types were built between 1914 and the late 1920s, compared with the number of biplanes. The reasons for this were primarily practical. With

2100-409: The engines mounted on the rear fuselage. The Bristol Siddeley Viper turbojet powerplant was selected to power the type. On 13 August 1962, the first of two prototypes conducted its first flight, a second aircraft followed it on 12 December that year. The second prototype was more aerodynamically representative of a production aircraft, and was fitted out with more equipment than the first prototype;

2160-469: The fuselage has a large equipment bay and, on some aircraft, one or two additional fuel tanks for extended operations. Having entered service as one of the first-generation executive jets, the British Aerospace 125 has been operated by a wide variety of customers, ranging from government and military operators to private customers and businesses, it has also seen use by several airlines. Many of

2220-402: The fuselage sides. The first parasol monoplanes were adaptations of shoulder wing monoplanes, since raising a shoulder mounted wing above the fuselage greatly improved visibility downwards, which was useful for reconnaissance roles, as with the widely used Morane-Saulnier L . The parasol wing allows for an efficient design with good pilot visibility, and was adopted for some fighters such as

2280-433: The general variations in wing configuration such as tail position and use of bracing, the main distinction between types of monoplane is where the wing is mounted vertically on the fuselage . A low wing is one which is located on or near the bottom of the fuselage. Placing the wing low allows good visibility upwards and frees the central fuselage from the wing spar carry-through. By reducing pendulum stability, it makes

2340-530: The introduction of ETOPS rules that allowed twin-engine jets to fly long-distance routes that were previously off-limits to them, Airbus was able to further develop the A300 as a medium- to long-range airliner to increased sales; Boeing launched its widebody twinjet, the Boeing 767 , in response. In the 1980s the Boeing 727 was discontinued, as its central engine bay would require a prohibitively expensive redesign to accommodate quieter high-bypass turbofans, and it

2400-449: The largest cargo aircraft capable of transporting outsize cargo , including strategic airlifters . Twin-jets tend to be more fuel-efficient than trijet (three engine) and quad-jet (four engine) aircraft. As fuel efficiency in airliners is a high priority, many airlines have been increasingly retiring trijet and quad-jet designs in favor of twinjets in the twenty-first century. The trijet designs were phased out first, in particular due to

2460-415: The low engine powers and airspeeds available, the wings of a monoplane needed to be large in order to create enough lift while a biplane could have two smaller wings and so be made smaller and lighter. Towards the end of the First World War, the inherent high drag of the biplane was beginning to restrict performance. Engines were not yet powerful enough to make the heavy cantilever-wing monoplane viable, and

British Aerospace 125 - Misplaced Pages Continue

2520-410: The more complicated design and maintenance issues of the middle engine mounted on the stabilizer. Early twinjets were not permitted by ETOPS restrictions to fly long-haul trans-oceanic routes, as it was thought that they were unsafe in the event of failure of one engine, so quad-jets were used. Quad-jets also had higher carrying capacity than comparable earlier twinjets. However, later twinjets such as

2580-487: The name changed to BAe 125 . When British Aerospace sold its Business Jets Division to Raytheon in 1993, the then-main variant of the jet became widely referred to as the Hawker 1000 . While the two prototypes were assembled at de Havilland's Hatfield site, final assembly of all production aircraft would take place at the Broughton factory near Chester until the 1990s. By the 2000s, the fuselage, wings and tailfin of

2640-410: The norm during World War II, allowing a high wing to be attached directly to the hull. As ever-increasing engine powers made the weight of all-metal construction and the cantilever wing more practical — first pioneered together by the revolutionary German Junkers J 1 factory demonstrator in 1915–16 — they became common during the post–World War I period, the day of the braced wing passed, and by

2700-411: The rear fuselage. It features a slightly swept wing , which is based on the larger de Havilland Comet wing planform, and uses large slotted flaps and airbrakes for operating from small airfields; the aircraft can be flown from hardened grass airstrips. The aircraft has a cylindrical fuselage with a one-piece wing mounted on the underside of the fuselage; most of the manufacturing and assembly work on

2760-658: The requirement that an aircraft be able to continue a takeoff if an engine fails after the takeoff decision speed is reached. Thus, with all engines operating, trijets must be able to produce at least 150% of the minimum thrust required to climb and quad-jets 133%. Conversely, since a twinjet will lose half of its total thrust if an engine fails, they are required to produce 200% of the minimum thrust required to climb when both engines are operating. Because of this, twinjets typically have higher thrust-to-weight ratios than aircraft with more engines, and are thus able to accelerate and climb faster. Low-wing A monoplane

2820-400: The smaller 125-800 and larger 125–1000. The 125–1000, which conducted its first flight on 16 June 1990, had several changes to give the type a reported intercontinental range, including the adoption of the newly developed Pratt & Whitney Canada PW300 engine and new digital avionics, such as FADEC . Following Raytheon's purchase of British Aerospace's Business Jet Division during the 1990s,

2880-420: The start of the project, de Havilland had determined that a successful business jet would require several variables to be met, including a range of at least 1,000 miles (1,600 km), the speed and cost factors of a suitable jet engine to outperform turboprop -propelled competitors, and an engineering philosophy that favoured reliability and conventionality. The design team settled on a twin-engine aircraft with

2940-433: The subsequent production-standard aircraft incorporated several changes and improvements from the prototypes, such as a longer fuselage and a greater wingspan. The first production-standard aircraft performed its first flight on 12 February 1963. The first delivery to a customer took place on 10 September 1964. The aircraft went through many designation changes during its service life. Hawker Siddeley had bought de Havilland

3000-694: The third configuration both engines are within the fuselage, side-by-side, used by most fighters since the 1960s. Later fighters using this configuration include the Su-27 'Flanker', the F-15 Eagle , and the F-22 Raptor . The first twinjet to fly was the German fighter prototype Heinkel He 280 , flying in April 1941 with a pair of nacelled Heinkel HeS 8 axial-flow turbojets. The twinjet configuration

3060-453: The top of the fuselage. It shares many advantages and disadvantages with the shoulder wing, but on a light aircraft, the high wing has poorer upwards visibility. On light aircraft such as the Cessna 152 , the wing is usually located above the cabin, so that the wing spar passes over the occupants' heads, leaving the wing in the ideal fore-aft position. An advantage of the high-wing configuration

SECTION 50

#1732783938161

3120-474: The two in-production variants were re-designated as the Hawker 800 and Hawker 1000 respectively. The 125 is the only business jet to have been hijacked : in 1967, a chartered 125 carrying the former Congolese Prime Minister Moise Tshombe was diverted to Algeria by armed persons on board. The 125 is also likely to be the only business aircraft to survive being hit by an air-to-air missile : in August 1988,

3180-408: The type certificate and support responsibility for all 125s built was transferred to the reformed Beechcraft Corporation . As of October 2012, Beechcraft does not intend to restart production of its business jet lines; instead the company intends to alternatively sell or dismantle the production facilities for the 125 family. The BAe 125 is a low-winged monoplane , powered by two engines mounted on

3240-439: The useful fuselage volume near its centre of gravity, where space is often in most demand. A shoulder wing (a category between high-wing and mid-wing) is a configuration whereby the wing is mounted near the top of the fuselage but not on the very top. It is so called because it sits on the "shoulder" of the fuselage, rather than on the pilot's shoulder. Shoulder-wings and high-wings share some characteristics, namely: they support

3300-450: The way. On large passenger jets, the cost of the engines makes up a significant proportion of the plane's final cost. Each engine also requires separate service, paperwork, and certificates. Having two larger engines as opposed to three or four smaller engines will typically significantly reduce both the purchase and maintenance costs of a plane. Regulations governing the required thrust levels for transport aircraft are typically based upon

3360-665: The wing and fuselage is able to be done with them as separate items with the two being joined late in the production process. The wing has integral fuel tanks which contain most of the fuel. Early models of the aircraft were powered by several versions of the Bristol Siddeley Viper turbojet engine, while later aircraft have adopted more recent turbofan powerplants such as the Garrett TFE731 and Pratt & Whitney Canada PW300 . Both engines drive an electrical generator and hydraulic pump which supply power to

3420-493: The year before the project had started, but the legacy brand and "DH" designation was used throughout development. After the jet achieved full production, the name was changed to "HS.125" except for American exports which retained the DH.125 until it was replaced by BH.125 for Beechcraft-Hawker. When Hawker Siddeley Aircraft merged with the British Aircraft Corporation to form British Aerospace in 1977,

3480-662: Was also used by the Royal Air Force as a navigation trainer, as the Hawker Siddeley Dominie T1 , and was operated by the United States Air Force as a calibration aircraft, under the designation C-29 . In 1961, de Havilland began work upon a small business jet, then known as the DH.125 Jet Dragon , which was intended to replace the piston engined de Havilland Dove , a successful business aircraft and light transport. Prior to

3540-656: Was soon supplanted by twinjets for the narrow-body market; Airbus with the A320 , and Boeing with the 757 and updated "classic" variants of the 737 . During that decade only McDonnell Douglas continued development of the trijet design with an update to the DC-10 , the MD-11 , which initially had a range advantage over its closest medium wide-body competitors which were twinjets, the in-production Boeing 767 and Airbus A300/A310. In contrast to McDonnell Douglas sticking with their existing trijet configuration, Airbus (which never produced

3600-484: Was used for short-range narrow-bodied aircraft such as the McDonnell Douglas DC-9 and Boeing 737 . The Airbus A300 was initially not successful when first produced as a short-range widebody, as airlines operating the A300 on short-haul routes had to reduce frequencies to try and fill the high-capacity aircraft, and lost passengers to airlines operating more frequent narrow-body flights. However, after

#160839