Photograph:
de Havilland DHC-3 Otter VH-SBR (c/n 247) at Bankstown, NSW in June 1968 (David C Eyre)
Country of origin:
Canada
Description:
Single-engine high-wing utility transport
Power Plant:
One 448 kw (600 hp) Pratt & Whitney R-1340-S1H1-G nine-cylinder air-cooled radial engine
Specifications:
- Wingspan: 17.68 m (58 ft)
- Length: 12.75 m (41 ft 10 in)
- Height: 3.8 m (12 ft 7 in)
- Wing area: 34.8 m² (375 sq ft)
- Max speed at 1,524 m (5,000 ft): 257 km/h (160 mph)
- Cruising speed: 222 km/h (138 mph)
- Economical cruising speed at 2,438 m (8,000 ft): 209 km/h (130 mph)
- Stalling speed: 93 km/h (58 mph)
- Initial rate of climb at sea level: 224 m/min (735 ft/min)
- Service ceiling: 5,730 m (18,800 ft)
- Cruising range: 1,431 km (889 miles)
- Max range: 1,545 km (960 miles)
- Max endurance: 9.4 hrs
- Take-off distance over 15 m (50 ft) obstacle: 400 m (1,310 ft)
- Landing distance over 15 m (50 ft) obstacle: 297 m (975 ft)
- Fuel capacity: 830 litres (178 Imp gals)
- Empty weight: 1,891 kg (4,168 lb)
- Disposable load: 1,646 kg (3,629 lb)
- Loaded weight: 3,629 kg (8,000 lb)
History:
Like its predecessor, the DHC-2 Beaver, the de Havilland DHC-3 Otter was developed in Canada to operate in undeveloped areas such as those in northern Canada. The design was initiated in January 1951, and the prototype flew for the first time on 12 December 1951 at Downsview in Ontario, being known for a short period as the King Beaver. Designed with a single-engine, a high-wing, and a fixed tailwheel-type undercarriage, the Otter offered rugged qualities and short-field performance, having the ability also to operate on skis, floats, amphibious floats, or wheels.
During 1953 de Havilland demonstrated the Otter to the US Army where it exhibited its ability to operate with substantial loads from small unprepared fields. Subsequently it was obtained in some numbers by that service and a number of others. Designated YU-1, six service trials aircraft entered US Army service in March 1955 and were used in Alaska. The type performed well in the utility role in Vietnam and earned great respect for its work in that conflict, some 23 examples being lost to hostile action and / or accidents.
Deliveries of production U-1As began in 1956 and these were attached to Army Aviation Transport Companies. The Otter’s cabin was 5 m (16 ft 6 in) long with a 1.5 m (5 ft) square cross-section, this providing space for nine passengers, with a tenth alongside the pilot, or 7 m³ (345 cub ft) of cargo space when the seats were folded along the cabin walls. A 0.7 m (27 in) diameter hatch in the rear of the cabin could be used for cargo and supply dropping, or as a position for a survey camera. In the ambulance role the Otter could carry six stretchers and three passengers in the cabin.
A total of 460 DHC-3 Otters was built, 233 being supplied to the US Army as U-1A, 18 to the US Navy as the UC-1, these later becoming the U-1B in 1962, and 66 to the Royal Canadian Air Force (RCAF) as the CSR-123. RCAF aircraft were engaged in Arctic search-and-rescue duties, paratroop dropping and aerial survey work. It was also operated in the amphibious role, being fitted with Edo floats, the mainwheels retracting into wells in the underside of the floats, and the nosewheels lifting and turning to lie flat on top of the floats.
One was used by the Canadian Defence Research Board for testing large wing flaps and a quadricycle undercarriage for STOL work, and one was fitted with a General Electric J-85 turbojet in the rear of the cabin with adjustable exhaust nozzles on the rear of the fuselage. Otters were exported to a number of overseas air forces. Examples accompanied the US Operation Deep Freeze expedition to the Antarctic in the years 1956-1958, and one served with the Commonwealth Trans Antarctic Expedition in 1957-1958, making a flight over the South Pole on 6 January 1958.
A number of Otters have been seen in Australia over the years. Two A100-390 (c/n 390) and A100-392 (c/n 392) were obtained by the Department of Supply in August 1960, to be flown and operated by the RAAF at the Woomera Rocket Range, SA by No 1 ATU. These aircraft were painted white overall and carried RAAF serials for some years, being used for freight and passenger work at Woomera. They were withdrawn from use in April 1967 when the RAAF withdrew from the area and their control was taken over by the Weapons Research Establishment (WRE), the aircraft being registered to the Department of Defence as VH-UPL (c/n 390) and VH-UPM (c/n 392).
In August 1980 the registrations were cancelled and they were flown to Bankstown, NSW for sale, being exported to Canada to Bannock Aerospace of Toronto where they became C-GSYR and C-GSYX. C-GSYR was operated by La Ronge, but was written off in an accident at Waddy Lake, Saskatchewan on 23 June 1981. G-GSYX entered service with Buffalo Airways, at some stage being fitted with a TPE331 turboprop and being operated in Alaska as N1018B.
Four others VH-EAW (c/n 241 – ‘Kikori’), VH-EAX (c/n 247 – ‘Kokopo’), VH-EAY (c/n 253 – ‘Kieta’) and VH-EAZ (c/n 258 – ‘Kerowagi’) were obtained by Qantas for operation in New Guinea in 1958. They were used in that region for some years from May 1958. The Otter had a greater payload than the Beaver, which was of great benefit in the hot and high conditions of New Guinea, but the climb rate was reduced and this caused some problems. On 3 August 1958 VH-EAY suffered substantial damage to its engine and airframe whilst landing at Tapini, swinging off the airstrip and hitting an open drain. The aircraft was later repaired. VH-EAZ in later years operated with Osprey Wings of Missinipe, Saskatchewan, as C-FXRI and was fitted with a turbine powerplant.
The Otters were withdrawn from Qantas use in September 1960, that company’s services being handed over to Trans Australia Airlines (TAA) in December that year (later Australian Airlines, later again Qantas). The Otters were re-registered VH-SBQ, VH-SBR ‘Keta’, later ‘Kundiawa’, VH-SBS, and VH-SBT ‘Kerowagi’ respectively. They continued in service until replaced, VH-SBR and VH-SBT being exported to Canada in 1966 and 1968 respectively. VH-SBQ was lost when it crashed near Samari, NG on 14 August 1961, this machine having spent its Australian life fitted with amphibious floats. VH-SBS crashed near Mendi in New Guinea on 2 December 1961. VH-SBR in later years was fitted with a turbine and operated as C-FYLZ in Ontario with Wabakimi Air.
In mid 1987 another example was imported and, fitted with amphibious floats, registered VH-TLS (c/n 355 – ex C-GOPP, 59-2217). This aircraft entered service with Tangalooma Transport Pty Ltd, QLD. It was in service for two years when it was badly damaged by a storm at Archerfield, QLD on 24 December 1989 and was returned to Canada for a rebuild, becoming C-FIPC. It did not return to Australia. It was initially built for the US Army. After its return to Canada it became C-FIPC, and later N53KA. In mid 1993 it was converted to Vazar turbine configuration by Aeroflite Industries of Vancouver becoming C-GOPP again. It was destroyed when it made a forced landing near Hoover Dam in Colorado on 31 December 1995 after an engine failure.
In more recent times further examples of the Otter have been imported. One, VH-OTR (c/n 373 – ex C-FBED, CF-BEO, 59-2225), was built as a U-1A-DH for the USAF. As a floatplane, it was first registered on 10 January 1997 and was based in northern Queensland alongside a couple of Beaver floatplanes, being used on tourist work. It was exported to Canada on 25 October 2005 where it became C-FBEO.
Another Otter VH-OTV² (c/n 250 – ex N373A, C-FWYH, IM-1731 [Indian Airforce]), a Volpar conversion, was a turboprop-powered amphibian and was first registered in Australia on 13 November 1997. It operated from Broome in Western Australia on tourist flights for a period and was registered to Vazar Pty Ltd. It does not seem to have had a great amount of work and was exported on 10 December 2008 to the United States where it became N510PR.
One Otter was purchased by the RNZAF in August 1960 as NZ6081 (c/n 126 – ex XL710, Bu 147574) for the Antarctic Flight, having previously operated with the Commonwealth Antarctic Expedition Flight in 1957-1958. This aircraft was obtained from the US Navy in a damaged condition in August 1960 and conveyed from Christchurch to Wellington by USAF Douglas C-124 Globemaster in October 1960 for repair. Its first flight following repair was in November 1961 but on 25 May 1962 it was flown to Wigram for storage.
Although allotted the RNZAF serial NZ6801 it was never painted on the aircraft. NZ6081 was overhauled, placed in storage and never used operationally. It was sold in Canada in June 1963. This aircraft was known for making the first single-engine aircraft crossing of the Antarctic on 6 January 1958 when operating with the British Antarctic Expedition, covering a distance of 1,848 km (1,148 miles) from the British base to the New Zealand Scott Base.
Subsequently the New Zealand Antarctic Flight was disbanded and the Otter aircraft was sold by tender to Georgian Bay Airways of Toronto, Canada on 18 February 1963, having completed a total of 508 hours. It was flown from Wigram to Wellington on 14 June 1963 and eventually became ZK-CFH on 9 July 1963 but was removed from the register on 1 August 1963 and shipped to Canada where it became CF-PNV in 1963. It crashed at Lynn Lake, Manitoba in May 1976 and was expected to be re-engined during its re-construction with a turbine but this did not occur and it became N63535 in Washington. It was placed in storage awaiting its rebuild.
In the 1950s a number of US Navy Otters passed through Christchurch on their way to the Antarctic on board American ships.
In 2005 a further Otter arrived in New Zealand for tourist work. This aircraft was obtained by Volcanic Air Safaris for operations as a floatplane on tourist flights from Lake Rotorua, becoming ZK-VAS (c/n 35 – ex C-FXGA, N511BW, C-GOFA, 3677). It was originally built for the RCAF, and operated with that service from 1954 to 1977. It then operated with the Ontario Ministry of Natural Resources until 1986 when it went to Boundary Water Inc in Minnesota, Temsco Airlines of Ketchikan, Alaska, Taquan Air Services, Hilltop Aviation of Jay, Maine, and Air Saguenay in Quebec.