DHC-1 Chipmunk
The first true postwar aviation project was the DHC-1 Chipmunk, designed as a primary trainer, a replacement for the venerable de Havilland Tiger Moth. The Chipmunk was an all-metal, low wing, tandem two-place, single-engine airplane with a conventional tail wheel landing gear. It had fabric-covered control surfaces and a clear plastic canopy covering the pilot and passenger/student positions. The production versions of the airplane were powered by a 145 hp in-line de Havilland Gipsy Major "8" engine.
The Chipmunk prototype first flew on 22 May 1946 in Toronto and had a total production run of 158 Chipmunks for RCAF use while de Havilland (UK) produced 740 airplanes for training at various RAF and University Air Squadrons during the late 1940s and into the 1950s. The DHC-1 Chipmunk was still being used as a training aircraft by the UK's Army Air Corps up until 1995.
At the present, October 2011, the Chipmunk is in service with the RAF Battle of Britain Memorial Flight and RN Historic Flight, it is used to train pilots to fly 'taildraggers' as a pre-requisite to flying the flight's Supermarine Spitfires and Hawker Hurricanes. All of the RAF's modern aircraft have tricycle undercarriage, so pilots are unfamiliar with tail wheel aircraft.
DHC-2 Beaver
Returning to designing purpose-built aircraft for Canada's north, the DHC-2 Beaver was developed in 1947. After a survey of Canada's bush pilots, including Punch Dickins, the need for a rugged, highly versatile aerial truck which could take off and land almost anywhere, carry a large half-ton load and be very reliable, formed the basis of a new specification. The first of the STOL family that de Havilland would produce, the Beaver would carve a niche into the bush plane market.
In the civilian sector, the Beaver soon excelled on wheels, skis and floats, and in 1951, the Beaver would be selected by the US Air Force and Army as a new liaison aircraft. In the nine years that followed, 968 L-20As were delivered to the armed forces, most going to the Army. They served in both the Korean War and Vietnam Wars, hauling freight and personnel around the battlefields, mapping enemy troop positions, leading search/rescue missions, and relaying radio traffic, among other missions. In 1962, the L-20 was re-designated the U-6A, and many remaining examples remained in service well into the 1970s. Beavers were also purchased and used by the military services of numerous other nations, including Britain, Chile and Colombia.
With almost 1,700 built in a production run lasting two decades, civilian-owned Beavers continue plying their trade in over 50 countries all around the world. A turbine-conversion, the Turbo Beaver (DHC-2 Mk.III) first flew in December 1963. This version featured a Pratt & Whitney PT6A-6 turboprop, which offered lower empty and higher takeoff weights, and even better STOL performance. The Turbo Beaver's cabin was also longer, allowing maximum accommodation for 11, including the pilot. Externally, the Turbo Beaver had a much longer and reprofiled nose, and squared off vertical tail. DHC also offered conversion kits enabling piston-powered Beavers to be upgraded to Turbo standard. Other conversions have been performed by a number of companies including Kenmore Aviation and Viking Air.
DHC-3 Otter
Another in de Havilland Canada's successful line of rugged and useful STOL utility transports, the Otter was conceived to be capable of performing the same roles as the earlier and highly successful Beaver, but was bigger, the veritable "one-ton truck."
Using the same overall configuration of the earlier and highly successful DHC2 Beaver, the Otter is much larger overall. The Otter began life as the King Beaver, but compared to the Beaver is longer, has greater span wings and is much heavier. Seating in the main cabin is for 10 or 11, whereas the Beaver could seat six. Power is supplied by a 450 kW (600 hp) Pratt & Whitney R1340 Wasp radial. Like the Beaver, the Otter can be fitted with skis and floats. The amphibious floatplane Otter features a unique four unit retractable undercarriage, with the wheels retracting into the floats.
Design work at de Havilland Canada began on the DHC3 Otter in January 1951, the company's design efforts culminating in the type's first flight on 12 December 1951. Canadian certification was awarded in November 1952.
After de Havilland Canada demonstrated the Otter to the US Army, subsequently that service went on to become the largest DHC3 operator (as the U1). Other military users included Australia, Canada and India.
Small numbers of Otters were converted to turbine power by Cox Air Services of Alberta, Canada. Changes included a Pratt & Whitney Canada PT6A turboprop, a lower empty weight of 1692 kg (3705 lb) and a higher maximum speed of 267 km/h (144 kt). It was called the Cox Turbo Single Otter. A number of other after market PT6 conversions have also been offered.
The Otter found a significant niche as a bush aircraft and today it remains highly sought after.
DHC-4 Caribou
de Havilland Canada's fourth design was a big step up in size compared with its earlier products, and was the first powered by two engines, but the DHC-4 Caribou was similar in that it is a rugged STOL utility. The Caribou was primarily a military tactical transport that in commercial service found itself a small niche in cargo hauling.
de Havilland Canada designed the DHC-4 in response to a US Army requirement for a tactical airlifter to supply the battlefront with troops and supplies and evacuate casualties on the return journey. With assistance from Canada's Department of Defence Production, DHC built a prototype demonstrator that flew for the first time on 30 July 1958.
Impressed with the DHC4's STOL capabilities and potential, the US Army ordered five for evaluation as YAC-1s and went on to become the largest Caribou operator, taking delivery of 159. The AC-1 designation was changed in 1962 to CV-2, and then C-7 when the US Army's CV-2s were transferred to the US Air Force in 1967. US and Australian Caribou saw extensive service during the Vietnam War. In addition some US Caribou were captured by North Vietnamese forces and remained in service with that country through to the late 1970s. Other notable military operators included Canada, Malaysia, India and Spain.
The majority of Caribou production was for military operators, but the type's ruggedness and excellent STOL capabilities also appealed to a select group of commercial users. US certification was awarded on 23 December 1960. AnsettMAL, which operated a single example in the New Guinea highlands, and AMOCO Ecuador were early customers, as was Air America (a CIA front in South East Asia during the Vietnam War era for covert operations). Other Caribou entered commercial service after being retired from their military users.
In later years, some civilian Caribou were modified to turboprop standard, with varying successes. Today only a handful of Caribou, in any variant, are in civilian use.
DHC-5 Buffalo
Known originally as the Caribou II, the DHC-5 Buffalo tactical transport was basically an enlarged DHC-4 with turboprop engines and a T-tail. The DHC-5 had been developed to meet the requirements of the US Army for a transport that would be able to carry loads such as the Pershing missile, a 105 mm howitzer or 3/4-ton truck. Development costs were shared by the US Army, Canadian government and de Havilland Canada; the first of these transports made its maiden flight on 9 April 1964.
Hopes for large orders were dashed when the US Army was forced to transfer all heavy fixed-wing aircraft to the US Air Force, which had no interest in the aircraft. 122 were built in two production runs, including a handful of Buffalo aircraft for the US Army and four C-8 transports for the USAF. When no further orders resulted from the US Army evaluation of the DHC-5 (designated originally YAC-2 by the US Army, and later C-8A), the Canadian Armed Forces acquired 15 of the DHC-5A (designated CC-115): six were converted subsequently for deployment in a maritime patrol role.
Following delivery of 24 to the Brazilian Air Force and 16 to the Peruvian Air Force, the production line was closed down. In 1974, the company realised there was a continuing demand for the Buffalo and production of an improved Buffalo (DHC-5D) was initiated. This version had more powerful engines which permitted operation at higher gross weights, and offered improved all-round performance. In the early 1980s, de Havilland Canada attempted to modify the Buffalo for civilian use. The aircraft was to be branded as the "Transporter." After loss of the demonstration aircraft (SN 103 C-GCTC) at the 1984 Farnborough Airshow, the project was abandoned. Production of the Buffalo ended in 1982, but the last of 122 aircraft built was not delivered until April 1985.
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 commenced work on a twin turboprop variant of the DHC-3 Otter as a STOL twin turboprop commuter airliner and utility transport. The wings were lengthened, the rear fuselage, tail, and nose were redesigned and seating was increased to as many as 18.
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 'flaperons' (ailerons that act in unison with the flaps) to boost STOL performance. Compared with the later Series 200s and 300s, the 100s are distinguishable by their shorter noses, thinner propellers and smaller exhaust ports on the engines.
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,
DHC-7 Dash 7
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 (LCA) where noise requirements were particularly strict, and featured four slow-turning props to cut noise.
In order to allow the Dash 7 to achieve its excellent STOL characteristics the aircraft employs many aerodynamic devices. The wing flaps are double slotted and span approximately 75% of the trailing edge of the wing. In a typical STOL landing flaps will be set to 45° before landing which allows for a slower approach speed (typically 70–85 knots) and steeper descent. Upon touchdown the flaps immediately return to the 25° position which decreases the lift created by the wing thereby increasing braking effectiveness. The aircraft also employs two ground spoilers per wing, and two roll spoilers per wing. The roll spoilers' primary job is to augment the ailerons however upon touchdown all four roll spoilers activate along with all four ground spoilers to spoil much of the lift generated by the wing.
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. Maximum take-off weight was 42,000 lbs. Followed shortly after by the Series 102 (passenger variant) and the Series 103 (a combination passenger/freighter variant) which had more powerful engines.
de Havilland Canada Dash 8
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.
