The last installment of de Havilland Aircraft of Canada Ltd. History
DHC-6 Twin Otter
One of Canada's most successful commercial aircraft designs, with more than 800 built, the Twin Otter remains popular for its rugged construction and useful STOL performance.
Development of the Twin Otter dates back to January 1964, when de Havilland Canada started design work on a new STOL twin turboprop commuter airliner (seating between 13 and 18) and utility transport to replace the earlier single-engined DHC-3 Otter. The new aircraft was designated the DHC-6 and prototype construction began in November that year, resulting in the type's first flight on 20 May 1965. After receiving certification in mid-1966, the first Twin Otter entered service with longtime de Havilland Canada supporter, the Ontario Department of Lands and Forests.
The first production aircraft were Series 100s. Design features included double slotted trailing edge flaps and ailerons that can act in unison to boost STOL performance. Compared with the later Series 200s and 300s, the 100s are distinguishable by their shorter, blunter noses.
The main addition to the Series 200, which was introduced in April 1968, was the extended nose, which, together with a reconfigured storage compartment in the rear cabin, greatly increased baggage stowage area.
The Series 300 was introduced from the 231st production aircraft in 1969. It too featured the lengthened nose, but also introduced more powerful engines, thus allowing a 450 kg (1,000 lb) increase in takeoff weight and a 20 seat interior. All models are capable of being fitted with skis and floats. In addition, six 300S enhanced STOL performance DHC-6-300s were built in the mid 1970s.
Production on the Twin Otter ceased in late 1988. In 2010, Viking Air began producing the first all-new Twin Otter, the Series 400.
The four-engine DHC-7, popularly known as the Dash 7, was designed as a STOL (short takeoff and landing) 50-seat regional airliner capable of operating from strips as short as 915 m (3,000 ft) in length. It was meant to serve small city airports like the London City Airport where noise requirements were particularly strict, and featured four slow-turning props to cut noise.
The main design features to achieve such a capability were an advanced wing and four Pratt & Whitney PT6A turboprops. Double slotted trailing edge flaps run the entire span of the high mounted wing, dramatically increasing the lifting surface available for takeoff. Extra lift is also generated by the airflow over the wing from the relatively slow turning propellers. The wings also feature two pairs of spoilers each - the inboard pair also operate as lift dumpers, the outboard pair can act differentially in conjunction with the ailerons to boost roll control.
Financial backing from the Canadian Government allowed the launch of the DHC7 program in the early 1970s, resulting in the maiden flight of the first of two development aircraft on 27 March 1975. The first production Dash 7 flew on 3 March 1977, the type was certificated on 2 May 1977 and it entered service with Rocky Mountain Airways on 3 February 1978. The type made the first ever landing at London Docklands Heron's Quay in 1983 paving the way for London City Airport. In 1987 the Dash 7 inaugurated flight service at LCA, with Brymon Airways. The market for the city-to-city aircraft never fully materialized, however London City Airport saw Brymon Airways providing Dash 7 service from 1987, exploiting its excellent STOL capabilities.
The standard passenger carrying Dash 7 is the Series 100, while the type was also offered in pure freighter form as the Series 101. The only major development of the Dash 7 was the Series 150, which featured a higher maximum takeoff weight and greater fuel capacity, boosting range. The Series 151 was the equivalent freighter. Production of the Dash 7 ended in 1988, following Boeing's takeover of de Havilland Canada.
De Havilland Canada began development of the Dash 8 in the late 1970s in response to what it saw as a considerable market demand for a new generation 30 to 40 seat commuter airliner. The Dash 8 emphasized operational economics over STOL performance, which proved much more successful.
Like the Dash 7, the Dash 8 features a high mounted wing and T-tail, an advanced flight control system and large full length trailing edge flaps. Power is supplied by two Pratt & Whitney Canada PW120 series (originally designated PT7A) turboprops. The first flight of the first of two preproduction aircraft was on 20 June 1983, while Canadian certification was awarded on 28 September 1984. The first customer delivery was to NorOntair of Canada on 23 October 1984.
The aircraft was introduced just as an older generation of feederliners was becoming too old to maintain economically, and there were few other new aircraft designs of its size that were ready for purchase; the ATR-42 entered service a year later, while most other designs (Dornier 328, Fokker 50, etc.) were only started in response to the success of the Dash 8. To date over 1000 Dash 8's have been delivered. In April 2008, Bombardier announced that production of the 100, 200, and 300 series Dash 8's would be ended, leaving the Q400 as the only Dash 8 still in production. On June 2009, Bombardier commercial aircraft president Gary Scott stated that a stretched Q400 model will be "definitely part of our future", for possible introduction in 2013-14.
HMCS Bras d'Or (FHE 400)
was a hydrofoil built from 1960 to 1967 for the Royal Canadian Navy. It served in the Canadian Forces from 1968 to 1971 as a testing platform for anti-submarine warfare technology on an ocean-going hydrofoil. During sea trials in 1969, the vessel exceeded 63 knots (117 km/h; 72 mph), making her possibly the fastest warship in the world. The vessel was constructed at Marine Industries Limited of Sorel, Quebec, with de Havilland Canada the prime contractor.
The final chapters of de Havilland Aircraft of Canada Ltd.
The Canadian government privatized DHC and in 1986 sold the aircraft company to then Seattle-based Boeing. The government claimed to have guarantees from Boeing, not to discontinue any product lines, but shortly thereafter, Boeing discontinued both the successful Twin Otter, and the Dash 7. The jigs and specialised equipment for their manufacture were destroyed.
Boeing was in heavy competition with Airbus Industrie for a series of new airliners for Air Canada, at that time a Canadian Crown corporation. Boeing used the DHC purchase to further strengthen their commitment to their shared production contracts. The contract was particularity contentious. When Air Canada announced that Airbus had won the contract in 1988, amid claims of bribery, Boeing immediately put DHC up for sale, placing the company in jeopardy.
DHC was eventually acquired by Montreal-based Bombardier Aerospace in 1992. DHC was eventually incorporated into the Bombardier group of companies and the Dash-8 remains in production with a particular emphasis being placed on its quiet operation in comparison to other aircraft of a similar size.
On 24 February 2006, Viking Air of Victoria purchased the type certificates from Bombardier Aerospace for all the original De Havilland designs including:
DHC-6 Twin Otter
DHC-7 Dash 7
The ownership of the certificates gives Viking the exclusive right to manufacture new aircraft and they are now building the DHC-6 Viking Twin Otter Series 400 and have an order book for about 70 aircraft of this type.
Despite its demise, de Havilland Canada has left a legacy of innovative and unique aerospace designs and its products are still flying in considerable numbers worldwide.
Canadian Airline Blog
DHC-6 Twin Otter (The new Viking Series 400 Demonstrator.)
HMCS Bras d'Or (FHE 400)
Mon, Jun 6 2011 9:42 PM
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