de Havilland Canada DHC-3 Otter

DHC-3 Otter
Turbine Otter in Harbour Air livery
Role STOL utility transport
Manufacturer de Havilland Canada
First flight 12 December 1951
Introduction 1953
Status Active
Produced 1951-1967
Number built 466
Developed into DHC-6 Twin Otter

The de Havilland Canada DHC-3 Otter is a single-engined, high-wing, propeller-driven, STOL aircraft developed by de Havilland Canada. It was conceived to be capable of performing the same roles as the earlier and highly successful Beaver, but was overall a larger aircraft.

Contents

Design and development

When de Havilland Canada began design work on the "King Beaver" (the Otter's original name) in January 1951, it was trying to extend the company's line of rugged STOL utility transports that had begun with the Beaver. The single-engined, high-wing, propeller-driven DHC-3 Otter was conceived to be capable of performing the same roles as the Beaver, but was considerably larger, the veritable "one-ton truck" (in company parlance, the Beaver was the "half-ton truck").[1]

Using the same overall configuration of the earlier and highly successful DHC2 Beaver, the new design incorporated a longer fuselage, greater-span wings, and was 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 Wasp radial. Like the Beaver, the Otter can be fitted with skis or floats. The Otter served as the basis for the very successful Twin Otter, which featured two wing-mounted Pratt & Whitney Canada PT6 turboprops.

The Otter received Canadian certification in November 1952 and entered production shortly after.

Operational use

The DHC-3/CSR-123 Otter was used until 1980 by the Royal Canadian Air Force and its successor, the Air Command of the Canadian Forces. It was used in Search and Rescue, as the "CSR" denotes Canadian Search (and) Rescue (type 123). The engine is a Pratt & Whitney R-1340 (1,340 cubic inches) geared engine. The version used in the Otter was geared for lower prop revs and consequently lower airspeed. The electrics were 28 volts D.C. It was also operated on EDO floats on water and skis for winter operations on snow. The EDO floats also had wheels for use on runways (amphibious). It was used as army support dropping supplies on parachutes, and also non-parachute low-speed, low-altitude air drops, to support the Canadian Army on maneuvers. In the end it was operated by the Primary Air Reserve in Montreal, Toronto and Winnipeg, with approximately 10 aircraft at each base, as well as by the RSU (Regular (Forces) Support Units) at those bases. It was usually flown with a single pilot (Commissioned Officer) in the left seat and a Technical Air Crewman (NCO) in the right seat. It was stood down, and the Kiowa helicopter replaced it in Air Reserve squadrons.

Although the Otter found ready acceptance in bush airlines, as in a similar scenario to the DHC-2 Beaver, the United States Army soon became the largest operator of the aircraft (184 delivered as the U-1A Otter). Other military users included Australia, Canada, and India, but the primary role of the aircraft as a rugged bush plane continues to this day.

An Otter crossed the South Pole in 1957 (see Commonwealth Trans-Antarctic Expedition). The Otter is also popular in the skydiving community and can be found in many dropzones throughout the world.

Modifications

Some aircraft were converted to turbine power using a PT6A, Walter 601 (manufactured in the Czech Republic), or Garrett/Honeywell TPE331-10, by Texas Turbine Conversions. A Polish Pezetel radial engine has also been fitted. Re-engined aircraft have been offered since the 1980s by Airtech Canada as the DHC-3/1000 using current-production 1,000 hp (745 kW) PZL ASz-62 IR radials.[2]

Variants

Military operators

 Argentina
 Australia
 Bangladesh
 Burma
 Cambodia
 Canada
 Chile
 Colombia
 Costa Rica
 Ethiopia
 Ghana
 India
 Indonesia
 New Zealand
 Nicaragua
 Nigeria
 Norway
 Panama
 Paraguay
 Philippines
 United Kingdom
 United States

Accidents

On 9 August 2010, a DHC-3T registered to Anchorage-based GCI crashed about 17 miles (27 km) north of Dillingham, Alaska, while en route to a private fishing lodge.[3] Five of the nine people on board were killed, including former Alaska Senator Ted Stevens. Surviving passengers included former NASA administrator Sean O'Keefe and his teenage son, both of whom sustained injuries.[4]

Specifications (Landplane)

Data from Jane's Civil and Military Aircraft Upgrades 1994-95[5]

General characteristics

Performance

See also

Related development
Aircraft of comparable role, configuration and era

Related lists

References

Notes
  1. ^ Rossiter 1998, p. 55.
  2. ^ Taylor 1988 p. 17.
  3. ^ Trimble, Stephen. "EADS executive survives Alaska air crash, but former senator killed." flightglobal.com, 10 August 2010. Retrieved: 10 August 2010.
  4. ^ Bohrer, Becky. "Plane crashes in Alaska kills former Alaska Sen. Ted Stevens, ex-NASA chief survives." The Associated Press. via 680news.com, 10 August 2010. Retrieved: 10 August 2010.
  5. ^ Michell 1994, p.24.
Bibliography
  • Hayes, Karl E. DHC-3 Otter - A History (CD-ROM). Crakaig, Killiney Hill Road, Killiney, Co. Dublin, Ireland: Karl E. Hayes Publisher, 2006. (also available via CANAV Books, Toronto)
  • Hotson, Fred W. The de Havilland Canada Story. Toronto: CANAV Books, 1983. ISBN 0-07-549483-3.
  • Michell, Simon. (ed.). Jane's Civil and Military Aircraft Upgrades 1994-95. Coulsdon, UK: Jane's Information Group, 1994. ISBN 0-7106-1208-7.
  • Milberry, Larry. Aviation In Canada. Toronto: McGraw-Hill Ryerson Ltd., 1979. ISBN 0-07-082778-8.
  • Molson, Ken M. and Harold A. Taylor. Canadian Aircraft Since 1909. Stittsville, Ontario: Canada's Wings, Inc., 1982. ISBN 0-920002-11-0.
  • Rossiter, Sean. The Immortal Beaver: The World's Greatest Bush Plane. Vancouver: Douglas & McIntyre, 1999. ISBN 1-55054-724-0.
  • Rossiter, Sean. Otter & Twin Otter: The Universal Airplanes. Vancouver: Douglas & McIntyre, 1998. ISBN 1-55054-637-6.
  • Taylor, John W.R., ed. Jane's All The World's Aircraft 1988-89. Coulsdon, UK: Jane's Defence Data, 1988. ISBN 0-7106-0867-5.

External links