De Havilland Canada DHC-6 Twin Otter

Article

July 1, 2022

The De Havilland Canada DHC-6 Twin Otter is a Canadian twin-engine turboprop high-wing aircraft for 12 to 20 passengers with fixed nose landing gear.

Emergence

In 1964, DHC decided that the basic aerodynamic and technological concept of the De Havilland Canada DHC-3 Otter would be used for the innovative DHC-6. The DHC-3 design had a reserve of carrying capacity and strength, but their use was limited by the radial drive unit. A pair of Pratt & Whitney of Canada PT6A-6 turboprop engines with a power of 426 kW each, located on a strut rectangular wing with two-slot flaps, was chosen to power the new machine.

Development and Deployment

The DHC-6 prototype (CF-DHC-X) was flown on May 20, 1965, and was certified by the US FAA in July 1966. The first machine of the DHC-6-100 series was handed over to the Ontario Department of Agriculture and Forestry. He served mainly in fire investigation and transportation of fire brigades. The Twin Otter has also found application in a wide range of military users, such as the USAF, where it flies under the designation UV-18B, or the Fuerza Aérea de Chile. From the fourth production aircraft, the PT6A-6 engines were replaced by the PT6A-20 type with the same power, but with more favorable take-off characteristics. The total production reached the number of 115 machines. In April 1968, the DHC-6-200 version with an extended nose of the fuselage, where there was also a luggage compartment for passengers, was introduced into production. Both variants could have mounted skis, combined skis with wheels, or two floats instead of undercarriage wheels. In this case, the Twin Otters have a shorter nose and two auxiliary vertical surfaces on the VOP to compensate for the increased area in front of the center of gravity. From the 231st airframe, the DHC-6 was delivered in an improved version of the DHC-6-300, the first serial piece of which was delivered in the spring of 1969. It is powered by PT6A-27 engines of 486 kW, which significantly improved the characteristics of the machine in the STOL category. Twin Otters were also supplied with an additional tank for cargo weighing up to 272 kg, suspended under the fuselage. The DHC-6-300S version was equipped to achieve the highest operational safety at the cost of reducing the number of passengers to 11. On October 1, 2008, the prototype DHC-6-400 (C-FDHT) with PT6A-34 engines of 551 kW was flown. Limited series production of the variant was resumed with Viking Air, which bought the production plans and rights to the type.

Specifications

Data according to

Main technical data

Span: 19.81 m Length: 15.77 m Bearing area: 39.02 m² Empty weight: 3320 kg Take-off weight: 5670 kg

Performances

Maximum speed: 338 km/h Cruising speed: 290 km/h Rate of climb on the ground: 8.1 m/s Access: 8140 m Maximum range: 1775 km

Links

References

Literature

NÉMEČEK, Václav. Twin-engine jet and turboprop transport aircraft. 1st ed. Prague: Transport and Spoj Publishing House, 1981. (Aircraft Atlas). GENF, S. A. Aircraft encyclopedia. 1st ed. Ivanka pri Dunaji: Slovo, 1998. ISBN 80-85711-35-4. P. 77. NICCOLI, Riccardo. Aircraft The most important current and historical types. Prague: Ikar, 2001. 224 pp. ISBN 80-242-0651-x.

External links

Images, sounds and videos about de Havilland Canada DHC-6 Twin Otter at Wikimedia Commons De Havilland Canada DHC-6 Twin Otter camouflage Photogallery of the De Havilland Canada DHC-6 Twin Otter aircraft