Honeywell TPE331

Ads

De Havilland Canada DHC-3 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 plane.

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 450kW (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

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.

The Otter is also popular in the skydiving community and can be found in many dropzones throughout the world.

Military Operators

Cambodia,

Variants

DHC-3 Otter : Single-engined STOL utility transport aircraft.

CSR-123 Otter : STOL utility transport aircraft for the RCAF.
YU-1 Otter : Six test and evaluation aircraft for the U.S. Army.
U-1A Otter : STOL utility transport aircraft for the US Army.
UC-1 Otter : STOL utility transport aircraft for the United States Navy. Later redesignated U-1B Otter in 1962.

DHC-3-T Turbo-Otter : Otter fitted with a 494-kW (662-hp) PT6A-27 turboprop engine.

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-62IR radials.

Specifications

References

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.
Milberry, Larry. Aviation In Canada. Toronto: McGraw-Hill Ryerson Ltd., 1979. ISBN 0-07-082778-8.
Molson, Ken M. and Taylor, Harold A. 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.