De Havilland Canada DHC-3 Otter
Encyclopedia
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.
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.
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.
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.
Bangladesh
Myanmar
Chile
Costa Rica
Ethiopia
Ghana
Nicaragua
Nigeria
Panama
Paraguay
Philippines
, while en route to a private fishing lodge. 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.
Propeller (aircraft)
Aircraft propellers or airscrews convert rotary motion from piston engines or turboprops to provide propulsive force. They may be fixed or variable pitch. Early aircraft propellers were carved by hand from solid or laminated wood with later propellers being constructed from metal...
-driven, STOL
STOL
STOL is an acronym for short take-off and landing, a term used to describe aircraft with very short runway requirements.-Definitions:There is no one accepted definition of STOL and many different definitions have been used by different authorities and nations at various times and for a myriad of...
aircraft developed by de Havilland Canada
De Havilland Canada
The de Havilland Aircraft of Canada Ltd. company was an aircraft manufacturer with facilities based in what is now the Downsview area of Toronto, Ontario, Canada...
. It was conceived to be capable of performing the same roles as the earlier and highly successful Beaver
De Havilland Canada DHC-2 Beaver
The de Havilland Canada DHC-2 Beaver is a single-engined, high-wing, propeller-driven, STOL aircraft developed by de Havilland Canada, primarily known as a bush plane. It is used for cargo and passenger hauling, aerial application , and has been widely adopted by armed forces as a utility aircraft...
, but was overall a larger aircraft.
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").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
Pratt & Whitney
Pratt & Whitney is a U.S.-based aerospace manufacturer with global service operations. It is a subsidiary of United Technologies Corporation . Pratt & Whitney's aircraft engines are widely used in both civil aviation and military aviation. Its headquarters are in East Hartford, Connecticut, USA...
Wasp
Pratt & Whitney Wasp
-External links:*...
radial
Radial engine
The radial engine is a reciprocating type internal combustion engine configuration in which the cylinders point outward from a central crankshaft like the spokes on a wheel...
. 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
Pratt & Whitney Canada PT6
The Pratt & Whitney Canada PT6 is one of the most popular turboprop aircraft engines in history, and is produced by Pratt & Whitney Canada. The PT6 family is particularly well known for its extremely high reliability, with MTBO's on the order of 9000 hours in some models. In US military use, they...
turboprops.
The Otter received Canadian certification in November 1952 and entered production shortly after.
Operational use
Royal Canadian Air Force
The history of the Royal Canadian Air Force begins in 1920, when the air force was created as the Canadian Air Force . In 1924 the CAF was renamed the Royal Canadian Air Force and granted royal sanction by King George V. The RCAF existed as an independent service until 1968...
and its successor, the Air Command
Canadian Forces Air Command
The Royal Canadian Air Force , formerly Canadian Forces Air Command, is one of three environmental commands of the Canadian Forces...
of the Canadian Forces
Canadian Forces
The Canadian Forces , officially the Canadian Armed Forces , are the unified armed forces of Canada, as constituted by the National Defence Act, which states: "The Canadian Forces are the armed forces of Her Majesty raised by Canada and consist of one Service called the Canadian Armed 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
Edo Aircraft Corporation
Edo Aircraft Corporation was an American aircraft manufacturing company known primarily for manufacturing pontoons for floatplanes.-History:...
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
United States Army
The United States Army is the main branch of the United States Armed Forces responsible for land-based military operations. It is the largest and oldest established branch of the U.S. military, and is one of seven U.S. uniformed services...
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
Commonwealth Trans-Antarctic Expedition
The 1955–58 Commonwealth Trans-Antarctic Expedition was a Commonwealth-sponsored expedition that successfully completed the first overland crossing of Antarctica, via the South Pole...
). 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 powerTurboprop
A turboprop engine is a type of turbine engine which drives an aircraft propeller using a reduction gear.The gas turbine is designed specifically for this application, with almost all of its output being used to drive the propeller...
using a PT6A
Pratt & Whitney Canada PT6
The Pratt & Whitney Canada PT6 is one of the most popular turboprop aircraft engines in history, and is produced by Pratt & Whitney Canada. The PT6 family is particularly well known for its extremely high reliability, with MTBO's on the order of 9000 hours in some models. In US military use, they...
, Walter 601 (manufactured in the Czech Republic), or Garrett/Honeywell TPE331
Garrett AiResearch TPE-331
|-See also:-External links:* * *...
-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
Airtech Canada
Airtech Canada is a Canadian aerospace engineering firm established at the Peterborough Airport, Ontario in 1977. It specializes in modifying aircraft for a variety of roles, particularly aero-medical conversions. It has also marketed conversions for popular radial-engined transport aircraft such...
as the DHC-3/1000 using current-production 1,000 hp (745 kW) PZL ASz-62
Shvetsov ASh-62
-Bibliography:* * -External links:***...
IR radials.
Variants
- DHC-3 Otter : Single-engined STOL utility transport aircraft.
- CSR-123 Otter : STOL utility transport aircraft for the Royal Canadian Air ForceRoyal Canadian Air ForceThe history of the Royal Canadian Air Force begins in 1920, when the air force was created as the Canadian Air Force . In 1924 the CAF was renamed the Royal Canadian Air Force and granted royal sanction by King George V. The RCAF existed as an independent service until 1968...
. - YU-1 Otter : Six test and evaluation aircraft for the U.S. ArmyUnited States ArmyThe United States Army is the main branch of the United States Armed Forces responsible for land-based military operations. It is the largest and oldest established branch of the U.S. military, and is one of seven U.S. uniformed services...
. - U-1A Otter : STOL utility transport aircraft for the US Army.
- UC-1 Otter : STOL utility transport aircraft for the United States NavyUnited States NavyThe United States Navy is the naval warfare service branch of the United States Armed Forces and one of the seven uniformed services of the United States. The U.S. Navy is the largest in the world; its battle fleet tonnage is greater than that of the next 13 largest navies combined. The U.S...
. Later redesignated U-1B Otter in 1962.
- CSR-123 Otter : STOL utility transport aircraft for the Royal Canadian Air Force
- DHC-3-T Turbo-Otter : Otter fitted with either a PT6A-27 or PT6A-34 turboprop engine.
Military operators
- Royal Australian Air ForceRoyal Australian Air ForceThe Royal Australian Air Force is the air force branch of the Australian Defence Force. The RAAF was formed in March 1921. It continues the traditions of the Australian Flying Corps , which was formed on 22 October 1912. The RAAF has taken part in many of the 20th century's major conflicts...
- Two Otters (RAAF serial A100-1 and 2) were in service with the RAAF from 1961 to 1967. The aircraft were used for passenger and freight transport duties at the Weapons Research Establishment, Woomera, South AustraliaWoomera, South AustraliaThe town, or village, of Woomera is located in the south east corner of the Woomera Prohibited Area ; colloquially known as the Woomera Rocket Range...
.- No. 1 Air Trials Unit
Bangladesh
- Bangladesh Air ForceBangladesh Air ForceThe Bangladesh Air Force , is the air arm of the Bangladesh Armed Forces. Bangladesh Air Force currently employs more than 22,000 personnel including 600+ Pilots.-History:...
Myanmar
- Burma Air Force
- Royal Cambodian Air ForceRoyal Cambodian Air ForceThe Royal Cambodian Air Force is the branch of the Royal Cambodian Armed Forces which is charged with operating all military aircraft in Cambodia.-Organization:...
- Former operator.
- Royal Canadian Air ForceRoyal Canadian Air ForceThe history of the Royal Canadian Air Force begins in 1920, when the air force was created as the Canadian Air Force . In 1924 the CAF was renamed the Royal Canadian Air Force and granted royal sanction by King George V. The RCAF existed as an independent service until 1968...
- Royal Canadian Mounted PoliceRoyal Canadian Mounted PoliceThe Royal Canadian Mounted Police , literally ‘Royal Gendarmerie of Canada’; colloquially known as The Mounties, and internally as ‘The Force’) is the national police force of Canada, and one of the most recognized of its kind in the world. It is unique in the world as a national, federal,...
Chile
- Chilean Air ForceChilean Air ForceThe Chilean Air Force is the air force of Chile, a branch of the Chilean military.-History:The first step towards the current FACh was taken by Teniente Coronel Pedro Pablo Dartnell, when he founded the Servicio de Aviación Militar de Chile on December 20, 1910, being trained as a pilot in France...
Costa Rica
- Air Surveillance Service
Ethiopia Ghana
- Ghana Air ForceGhana Air ForceThe Ghana Air Force is the air force of the African nation of Ghana. The GAF, along with the Ghanaian Army and Navy, make up the armed forces of Ghana which are controlled by that nation's Ministry of Defence....
- Indian Air ForceIndian Air ForceThe Indian Air Force is the air arm of the Indian armed forces. Its primary responsibility is to secure Indian airspace and to conduct aerial warfare during a conflict...
- Royal New Zealand Air ForceRoyal New Zealand Air ForceThe Royal New Zealand Air Force is the air arm of the New Zealand Defence Force...
Nicaragua
- Nicaraguan Air ForceNicaraguan Air ForceThe Nicaraguan Air Force continues the former Sandinista air units. Before 1979 the Nicaraguan National Guard had some air units .-Air force:...
Nigeria- Royal Norwegian Air ForceRoyal Norwegian Air ForceThe Royal Norwegian Air Force is the air force of Norway. It was established as a separate arm of the Norwegian armed forces on 10 November 1944. The RNoAF's peace force is approximately 1,430 employees . 600 personnel also serve their draft period in the RNoAF...
Panama
- Panamanian Public Forces
Paraguay
- Paraguayan Air Force 1 DHC-3 donated by Argentina.
Philippines- Royal Air ForceRoyal Air ForceThe Royal Air Force is the aerial warfare service branch of the British Armed Forces. Formed on 1 April 1918, it is the oldest independent air force in the world...
- United States Air ForceUnited States Air ForceThe United States Air Force is the aerial warfare service branch of the United States Armed Forces and one of the American uniformed services. Initially part of the United States Army, the USAF was formed as a separate branch of the military on September 18, 1947 under the National Security Act of...
- United States ArmyUnited States ArmyThe United States Army is the main branch of the United States Armed Forces responsible for land-based military operations. It is the largest and oldest established branch of the U.S. military, and is one of seven U.S. uniformed services...
- United States NavyUnited States NavyThe United States Navy is the naval warfare service branch of the United States Armed Forces and one of the seven uniformed services of the United States. The U.S. Navy is the largest in the world; its battle fleet tonnage is greater than that of the next 13 largest navies combined. The U.S...
Accidents
On 9 August 2010, a DHC-3T registered to Anchorage-based GCI crashed about 17 miles (27.4 km) north of Dillingham, AlaskaDillingham, Alaska
- Natural resources :Dillingham was once known as the Pacific salmon capital of the world and commercial fishing remains an important part of the local economy...
, while en route to a private fishing lodge. Five of the nine people on board were killed, including former Alaska Senator Ted Stevens
Ted Stevens
Theodore Fulton "Ted" Stevens, Sr. was a United States Senator from Alaska, serving from December 24, 1968, until January 3, 2009, and thus the longest-serving Republican senator in history...
. Surviving passengers included former NASA administrator Sean O'Keefe
Sean O'Keefe
Sean O'Keefe is the CEO of EADS North America, a subsidiary of the European aerospace firm EADS, a former Administrator of NASA, and former chancellor of Louisiana State University . O'Keefe is also a former member of the board of directors of DuPont...
and his teenage son, both of whom sustained injuries.