BAC 1-11

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The BAC 1-11, or One-Eleven, was a short-range jet airliner designed by Hunting Aircraft and produced by the British Aircraft Corporation (BAC) after Hunting was merged with several other British aviation firms in 1960.

Image:Court.line.bac1-11.592pix.jpg

The 1-11 was designed to replace the successful Vickers Viscount on its existing routes with British European Airways (BEA) and other operators. The 1-11 was the second short-haul jet airliner to enter service, the first being the French Sud Caravelle, but due to its later entry date the 1-11 was able to take advantage of greatly improved engine fuel economy and was less expensive to operate. This made it moderately popular, with a launch-customer list including over half of the sales to the United States, with an eventual production run of well over 200. The 1-11 was one of the most successful British airliner designs, and served from its introduction in the early 1960s until its widespread retirement in the 1990s due to noise restrictions.

1 History
- 1.1 Models
2 Specifications(BAC 1-11-200)
3 Military Operators
4 External links
5 Related content

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History

In the mid-1950s British European Airways (BEA) started looking for a jet-powered 600mph design to replace its successful, but somewhat slow, Vickers Viscounts then in service. Vickers and Hunting both started design work on such a plane in 1956, the Vickers being a 140-seat downsizing of their existing VC-10 design effort then underway as the VC-11, while Hunting's aircraft was an all new 107-seat design.

In 1960 Hunting merged with Vickers, Bristol, and English Electric to form BAC. In 1961 BAC management decided to continue work on the then-stalled 1-11 project with internal funding. The short delay was to prove advantageous, as the design was able to use the newly developed Rolls-Royce Spey turbofan engines for greatly increased fuel economy. BAC was concerned the aircraft was too large to fit the Viscount role in the original Hunting configuration, and therefore redesigned it with a smaller 80-seat fuselage. This design became the Model 200, the original design retroactively becoming the 100.

On May 9 1961 British United Airways placed the first order for 10 Model 200 aircraft, followed on October 23 by an order for 6 from Braniff Airways in the United States. Other orders soon followed from Mohawk Airlines for 4, Kuwait Airways for 3 aircraft and by Central African Airways for 2 aircraft. Braniff Airways subsequently doubled its order to 12 aircraft while Aer Lingus ordered 4 aircraft. Western Airways ordered 10 aircraft but later cancelled. Image:Mohawk N1122J.png

In May 1963 BAC announced the development of the Model 300 and 400. The new versions used the Mk. 511 version of the Spey with increased power, allowing for more fuel load, and therefore longer range. There were a number of minor design changes as well, with the main visual difference being to the nose wheel doors. The original 200 also had a much rounder nose cone which was replaced with a more pointed one, a change that was later retroactively applied to all 200's as well. The primary difference between the 300 and 400 was the selection of equipement and avionics in the cockpit, with the 400 intended for sales to the US, and therefore equipped with US instruments. This proved to be a shrewd move; American Airlines ordered 15 aircraft on July 17 1963, bringing the total number of firm orders to 60 (plus options for many more), easily enough for BAC to break even.

The prototype, G-ASHG, rolled off the Hurn production line on July 28 1963, with the first flight following soon after on August 20. Unfortunately this aircraft crashed killing all on board on October 22, and an investigation into the cause led to the discovery of the conditions leading to deep stall, when the airflow over the wing "blanks" the tail, meaning the aircraft loses pitch control. Although the problem itself seemed not all that simple to solve, BAC added a stick shaker to avoid the problem in the first place, and redesigned the wing's leading edge to lessen the impact.

Depite this early setback the flight test program continued and customer confidence remained high. American Airlines and Braniff Airways both exercised their options and placed more orders in February 1964. Further orders were received from Mohawk Airlines, Philippine Airlines and from Helmut Horten who ordered the first Executive aircraft. By the end of 1964 13 aircraft had rolled off the production line.

After nearly 2 years of flight testing the aircraft was certified and the first 1-11 delivery, G-ASJI to British United Airways, took place on January 22 1965. After several weeks of route proving flights, the first revenue service commenced on April 9 from Gatwick to Genoa. Braniff took delivery of their first aircraft on March 11, while Mohawk Airlines received their first on May 15. Deliveries continued, and by the end of 1965 34 aircraft had been received by their customers. Demand continued to be high and additional orders were received throughout this period, and a second production line was set up at Weybridge.

In 1967 a larger 119-seat version was introduced as the Model 500, in response to increasing patronage of BEA's short-haul routes. 8ft 4in (2.54 m) added ahead of the wing, 5ft 2in (1.57 m) behind, the wings were widened by 5 ft (1.5 m), and the latest Mk.512 version of the Spey was used. The 500 was not offered in the US as this market niche was now being filled by the Boeing 727, but it nevertheless sold in Europe, with a major order from BEA. The final production version, the Model 475, combined the smaller Model 400 fuselage with the higher power of the Model 500 and was intended for hot and high operations. Only a few were sold.

Total deliveries for 1966 stood at 46 aircraft, and between 1967 to 1971 another 120 were delivered. At this point orders slowed, but production continued until 1982 with a further 35 aircraft being delivered. A planned Model 670, with better fuel economy, was not proceeded with.

Production then continued in Romania as the ROMBAC 1-11, with kits being shipped for assembly there. The first flight of a ROMBAC 1-11 took place on September 18 1982, and production continued until 1989 with the 9th airframe was delivered. The production line had originally intended to deliver up to 80 aircraft, but the deteriorating political situation in Romania closed it early. Total production for the 1-11, from both British and Romanian factories, was 244, with a further 2 airframes being left incomplete in Romania.

1-11's served widely in the US until displaced by the locally-built Douglas DC-9 and Boeing 737 in the early 1970s. In Europe they were a common feature at all airports, and continued in widespread operations until the mid-1980s and into the 1990s. Many 1-11s then moved to smaller airlines, notably in the far east and Africa, with the last major operations being in Nigeria, where they were finally grounded after a major crash in 2002. Today only a handful are still operating, mainly in Africa, although corporate versions with VIP-interiors survive in the USA and Europe. Several dozen 1-11's are in storage and for sale around the world.

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