AIRCRAFT
The British Aerospace (BAe) 146 is a medium-sized commercial aircraft which was manufactured in the United Kingdom by BAe (which later became part of BAE Systems). Production of the type started in 1983, and was terminated in November 2003 following the worldwide slump in the aviation market after the September 11, 2001 attacks. In the early 90s, production had switched to an improved version known as the Avro RJ with more efficient engines, improved cabin, and digital avionics.A further-improved version, the Avro RJX, with advanced Honeywell AS977 turbofans, was announced in 1997. However, BAE Systems terminated the project in December 2001, having completed and flown only three aircraft - a prototype each of the RJX-85 and RJX-100, and a production RJX-100 for British European. The termination of the RJX project marked the end of commercial airliner-production in the United Kingdom.
The BAe 146/Avro RJ carries its four jet engines on a high wing above the fuselage. The aircraft has STOL capabilities and very quiet operation, and has been marketed under the name Whisperjet. It sees wide usage at small city-based airports. In its primary role it serves as a regional jet, short-haul airliner or feederliner. The freight-carrying version has the designation "QT" (Quiet Trader), while a convertible version is designated "QC".
The BAe 146 comes in three sizes, the -100, -200 and -300 models that have the same cockpit, engines and operating procedures. The equivalent Avro RJ versions are designated RJ70, RJ85, and RJ100, the number indicating the basic number of seats in each version, although all versions can accommodate more passengers depending on the seating arrangements. For example, the BAe-100/RJ70 seats 70 passengers five abreast, 82 six abreast or 94 in a high-density configuration. The aircraft are in wide use among European airlines, such as Lufthansa and SN Brussels Airlines.
One of very few commercial jets with 4 turbofans on a wing that is mounted on top of the fuselage, the BAe 146 also has a T-tail. (Another commercial aircraft with this configuration is the civil version of the Ilyushin Il-76.) Having extremely large flaps and spoilers, and a large split air brake mounted in the tail, the plane does not need reverse thrust on landing. Consequently, the four engines (supplied by U.S. manufacturer Lycoming) do not have this facility. The airplane can take off and land on extremely short runways, such as those at Mönchengladbach Airport, at Vágar Airport and at London City Airport, a converted dock.
The history of the model goes back to the 1960s and to design studies initiated at the Hatfield facility of the then-independent de Havilland Aircraft Co. (who had earlier created the first ever commercial jetliner, the Comet) for a small turboprop feederliner designated D.H. 123. This was a twin-engine, high-wing design, but further studies, which were continued at Hatfield after de Havilland had been absorbed into the Hawker Siddeley Aviation company (HSA), favored low-wing layouts with turbofan engines mounted on the rear fuselage.
These studies culminated in the HS 144 project, but lack of a suitable engine led the designers in April 1971 to revert to a high-wing layout using four smaller turbofans, the Avco Lycoming ALF 502R-5. In this form, as the HS 146, the project was formally launched on August 29, 1973, in partnership with the British government. However, due to the economic downturn of 1974-75 resulting from the oil crisis, the program was terminated in October 1974, at which time the HS146 reverted to project design status.
In substantially the same form as originally planned, the aircraft was re-launched on July 10, 1978, by British Aerospace - into which HSA had meanwhile been assimilated - once again with government financial assistance. From the start of development, two fuselage lengths were planned for models identified as the Series 100 and 200, and construction, development and flight testing proceeded in parallel.
The first Series 100 flew on September 3, 1981, followed by a second and third on January 25 and April 2, 1982. The first Series 200 (the fourth airframe completed) flew on August 1, 1982. Production of the BAe 146 was spread within BAe factories in the UK, and also internationally on a risk-sharing basis. In particular, Avco Aerostructures in the US produced the main wing torsion box, and Saab Scania in Sweden was responsible for the tailplane and all moving control surfaces. Pods for the ALF502 turbofans were produced in Northern Ireland by Short Brothers. Final assembly took place at Hatfield, but was transferred to the BAE Systems Regional Aircraft Centre at the historic Avro Airfield at Woodford in the early 1990s when Hatfield closed.
The BAe 146-100, with an overall length of 85 ft 11 in (26.19 m), provided for 82 passengers at 33 in. (84 cm) pitch, or up to a maximum of 94. This has the same powerplant as the 146-200, but a maximum takeoff weight of 84,000 lb. (38,102 kg).
The 146-200 differs only in length of fuselage and operating weights, with associated structural and system changes. It features a 2.41 m (7 ft 11 in) fuselage extension and reduced seat-distance costs. The -200 first flew in August 1982 and entered service six months later.
The RJ versions of the 146 family feature an improved cabin and Textron Lycoming (now Allied Signal Engines) LF507 turbofans, with FADEC (Full Authority Digital Engine/Electronic Control, which is part of the electronic instrumentation in modern aircraft cockpits). These engines have Category 3 auto-land capability. Deliveries of the first RJ model, the RJ85, began in April 1993 and it can seat up to 112 passengers.
A freighter version of the BAe146-200 was developed, with an upward-hinged door (in the rear fuselage port side) measuring 6 ft 6 in (1.98 m) in height by 10 ft 10 in (3.30 m) in width. Under a 1986 agreement with BAe, the Dothan Division of Hayes International Corp. in the U.S. was responsible for the detail design, manufacture and installation of the freight door and freight handling equipment, plus necessary structural changes to the aircraft. These were flown for this purpose as "green" airframes from the UK to the Hayes facility in Dothan, Alabama.
The BAe146-200 Freighter first flew on August 21, 1986, and can accommodate six standard LD-3 freight containers and carry a 22,000-lb. (9,980-kg.) payload. Military versions of the BAe146 have also been studied. Freight and small package carrier TNT Express operates BAe146-200QT (Quiet Trader) freighters.
Certification of the BAe146-100 was on May 20, 1983, and Dan-Air put the type into revenue service on May 27 soon followed by the RAF's Royal Flight squadron, whose special conversions were designated the BAe146-100 Statesman. The Series 200 was certificated in June, 1983, in the UK and US, allowing Air Wisconsin, a United Express airline, to become the first operator of the type on June 27.
In September, 1984, BAe announced that it was launching a BAe146-300, featuring a 3.2 m extension to the fuselage of the -200 to increase the standard seating to 122 at 32-in. (81-cm.) pitch, or 130 at 29-in. (74-cm.) pitch. It would also have more powerful engines and winglets.
However, this plan was modified during 1986 due to the requirements of airlines for higher efficiency rather than capacity, and the production 146-300 emerged as a 7 ft 10 in (2.39 m) stretch of the -200, without winglets or the proposed ALF 502R-7. Its gross weight was limited initially to 93,000 lb (42,180 kg), using the same ALF 502R-5 engines as the Series 200.
In this form, the Series 300 provided five-abreast seating for 100 passengers, and offered operating economics comparable to those of the Series 200. Deliveries began in December 1988. The MTOW was eventually increased to 104,000 lb (47,170 kg).
The aircraft have proven to be very useful on "high" density regional and short-haul routes. One of the main features of the BAe 146 that made it different from other regional aeroplanes is the fact that it features six-abreast seating which proves to be more comfortable than the more traditional four- or five-abreast seating of planes in its class. The plane is also renowned for its relatively low noise generation, a positive feature which won the hearts of many operators who wanted to fly in and out of noise stringent airports within cities.
Other versions included a BAe146-STA Military transport version.
There is also an RJ115. This has the same fuselage length as the RJ100, but has 6-abreast seating as standard. In a high-density layout, it can carry 128 passengers. See also Avro RJ70/85/100.
The ALF 502 turbofans were derived from Lycoming's helicopter turbo-shaft designs and suffered from reliability problems. The internal electronics were prone to overheating which could trigger an automatic shutdown of an engine with no option of in-flight restarting, and certain atmospheric conditions caused engine failure due to internal icing. As a result, BAe146 mechanics quipped that "BAe" stood for "Bring Another Engine." In recent years, there have been cases where toxic fumes from engine oil have entered the air-conditioning system and entered the cockpit, adversely affecting the pilots.
Altogether, there were 219 BAe146s delivered, and 168 Avro RJs delivered.
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