De Havilland Canada DHC-2 Beaver - Design and Development

Design and Development

In the immediate post-war era, de Havilland Canada management turned to the civilian market for continued work, aware that military contracts were unlikely to guarantee business. The company had recently hired Punch Dickins, a famous bush pilot, as Director of Sales, and he began an extensive program of collecting requests from other pilots in order to understand what they needed in a new aircraft. Almost without variation, the pilots asked for tremendous extra power and STOL performance in a design that could be easily fitted with wheels, skis, or floats. When de Havilland engineers noted that this would result in poor cruise performance, one pilot replied "You only have to be faster than a dog sled". Other suggestions were seemingly mundane but important in the bush plane world; for instance, full-sized doors were installed on both sides of the aircraft so it could be easily loaded no matter which side of a dock it tied up on. The doors were also made wide enough to allow for a 45 Imperial gallon drum to be rolled up into the aircraft.

On September 17, 1946, de Havilland officially put together a design team consisting of Fred Buller, Dick Hiscocks, Jim Houston and W. Jakimiuk, led by Phil Garratt. The new aircraft was specifically designed to be all-metal (unlike older designs like the famous Noorduyn Norseman), using “steel from the engine to the firewall, heavy aluminum truss frames with panels and doors throughout the front seat area, lighter trusses toward the rear and all monocoque construction aft”. At the time de Havilland Canada was still a British-owned company, and there were plans to fit the evolving design with a British engine. This limited power, so the wing area was greatly increased in order to maintain STOL performance. When Pratt & Whitney Canada offered to supply war-surplus 450 hp (340 kW) Wasp Jr engines at a low price, the aircraft ended up with extra power as well as the original long wing. The result was unbeatable STOL performance for an aircraft of its size.

After much testing, and with adjustments and improvements, the innovative airplane was ready for the sales circuit. It just needed a proper name. Since de Havilland Canada aircraft were all named after animals, it was decided that the new bush plane was much like the hard-working beaver. The first flight of the DHC-2 Beaver was in Downsview, Ontario by Second World War flying ace Russell Bannock on August 16, 1947. The first production aircraft was delivered to the Ontario Department of Lands and Forests, a design partner, in April 1948.

Initial sales were slow, perhaps two or three a month, but as the plane was demonstrated sales started to improve. A key event in the Beaver's history occurred the next year when the US Army started looking for a new utility aircraft to replace their Cessnas. The competition quickly boiled down to the Beaver and the Cessna 195, but the Beaver completely outperformed the 195, and with the outbreak of the Korean War, led to orders for hundreds of aircraft. Soon orders increased from around the world. When production finally ceased in 1967, 1,657 DHC-2 Beavers had been built.

The Beaver was designed for flight in rugged and remote areas of the world. Its short takeoff and landing capability made it ideal for areas normally only accessible by canoe or foot. Because it often flies to remote locations, often in cold climates, its oil reservoir filler is located in the cockpit and oil can be filled in flight. A series of upgrades to the basic design were incorporated into the design to further improve it. One major customer introduced the use of flat steps replacing the earlier tubes, a feature that is now almost universal.

In 1987, the Canadian Engineering Centennial Board named the DHC-2 one of the top ten Canadian engineering achievements of the 20th century.