The long history of aircraft design in Canada dates back to Wallace Turnbull, the first Canadian to test airfoil models in a wind tunnel (1902), and to the founding, in 1907, of the Aerial Experiment Association in Cape Breton, Nova Scotia, under the leadership of Alexander Graham Bell in partnership with J.A.D. McCurdy, F.W. Baldwin, together with the Americans, Thomas Selfridge and Glenn Curtiss.

Civil Aviation in Canada began with aerial surveys, mail deliveries, and barnstorming. With the discovery in the 1930s of rich mineral deposits in the northland, Canada led the world in air transportation. The heroic exploits of pilots and mechanics alike during this prewar period, earned them a proud place in the Canadian Aviation Hall of Fame.

R.B. Noorduyn, who had worked for Fokker and Bellanca before coming to Canada, produced, in 1935, the Norseman, the first aircraft designed specifically to operate on wheels, floats, or skis. It was the forerunner of the modern bushplane.

Geoffrey de Havilland, one of England’s most respected aircraft designers, produced the popular Moth biplane in the late 1920s. When Canadian flying clubs began widespread purchases of this plane, the company was quick to establish at Mount Dennis, a small facility, later moved to the present Downsview site, north of Toronto, to assemble these aircraft.

It was on the eve of a major Depression, and the fledgling company barely survived on repair work. World War II was well under way before the company fortunes changed with an avalanche of military orders. To cope with a torrent of design changes, refugee engineers from Poland were engaged in addition to experienced staff recruited from England.

Following World War II, Phil Garratt, de Havilland’s managing director, determined that Canada should produce aircraft of its own design for the domestic market. He retained a nucleus of wartime technical staff under the leadership of W. Jakimiuk, chief designer, and W.D. Hunter, engineering director.

“Jaki” had achieved fame in prewar Europe as the designer of an advanced series of Polish PZL fighter aircraft. “Doug” Hunter, a contemporary of Geoffrey de Havilland, had moved from the parent company to Canada to assist with the production of the wartime Mosquito.
 

Cited for his aeronautical design work on the Beaver and its flight capabilities for short take-off and landing (STOL), Richard Duncan Hiscocks, right, receives in 1954 the first ever annual McCurdy Award from J.A.D. McCurdy who piloted the Silver Dart on its maiden flight in Canada on February 23, 1909. [Photo, courtesy Bettie Hiscocks]

Under these leaders, a design team lost no time in proposing two projects: a two-seat trainer to replace the obsolete Moth and a bush plane. The latter, a more ambitious project, was postponed.

The Chipmunk flew in May 1946. It became popular for training and sport flying. To this day, it may still be seen performing aerobatics at a variety of air shows. To compete with the price of war surplus trainers proved difficult. Sales were slow at first. Later, with a substantial order for the Royal Air Force, the Chipmunk became the first Canadian design to be manufactured abroad.

The prognosis for an all-Canadian bushplane was not good. The return from the Chipmunk investment was slow. Stiff competition from the Norseman, still in production and popular with bush pilots, could be expected. There was also the threat of a new bush plane already under development by Sherman Fairchild, an American aircraft manufacturer from Long Island.

Anyone less sanguine than Phil Garratt would have hesitated. Since the Ontario Provincial Air Services, a large operator, would soon be retiring an aging fleet of biplanes and flying boats, time was of the essence. Somehow, within the company, he found the money for a “million-dollar gamble.”

The day to day activities in the design office were the responsibility of Fred Buller. A native of Vancouver, he attended UBC and the Boeing School of Aeronautics in Seattle. He began his career with North West Industries in Edmonton.

Later he moved to Central Aircraft, a subsidiary of de Havilland in 1943 and was invited to join the engineering team at Downsview, near Toronto, in 1944. He had a natural talent for design that was an inspiration to all who worked with him, and it was no accident that the first Beaver bore the registration FHB.

Early sketches of the Beaver are a far cry from the final product. An elegant, streamlined shape resembling a Chipmunk enlarged to accommodate a passenger cabin reflects the European background of the originators. A long slender de Havilland Gypsy engine contributed to the lines.

There was a natural preference for a de Havilland engine and Gypsy engines had powered many light aircraft with great success. For the Beaver, a more powerful version was required and the English company was working on one. It was unproven and to the critics the projections for a “stretched” Gypsy fell far short of requirements.

Prospective customers of the Beaver emphasized that speed was secondary when alternative modes of travel were canoe or dog sled. Of first importance was a short take-off and steep climb at low speeds to clear obstacles, a much needed characteristic lacking in existing bushplanes.

Floatplanes, in particular, were deficient. One operator quipped that a loaded Norseman depended upon the curvature of the earth for the take-off. Performance calculations showed that the Beaver would need considerable power to lift a one-half-ton payload from the small lakes and rivers that were the “norm” in the bush.

Phil Garratt made the pivotal decision. From Jim Young, president of Pratt and Whitney Canada, he heard that war surplus Wasp Junior engines that had never been used were available in mint condition. In fact, they produced about 50 percent more power than the Gypsy engine.

A few details, however, remained to be sorted out. The Wasp weighed 50 percent more than the Gypsy. A large diameter radial engine demanded drastic revisions to the structure. Engineering took these in its stride. If the “swan” seemed now to be an ugly duckling, the conversion was accepted with equanimity.

If the Beaver resembled its forebears, its details were very different. To produce high lift at low speeds, a rather thick wing and elaborate flap system had been adopted when the design was expected to be underpowered. This was retained.

The structure was entirely aluminium, to replace the fabric, plywood and tubular steel trusses that were troublesome in the bush. Pilot and co-pilot each had a door, important for ready access floating at a dock. Large cargo doors on either side brought the total to four, in contrast to many aircraft with a single door at the cabin rear.
 

A combination of abundant power and efficient wing made the Beaver a flying jeep innovatively capable of short take-off and landing (STOL), the first practical aircraft in the world to negotiate such revolutionary aerodynamics. The first flight of the Beaver occurred on August 16, 1947. It operated successfully in no less than 63 countries, performing equally well on wheels, skis or floats. Fifty years later, it is still a favourite of bush pilots and can be seen serenely gliding over landscape and northern lakes every day of the year. This Robert Bradford painting, The Beaver at Work, was rendered in 1982. [Photo, courtesy Dr. David M. Baird/ Robert Bradford]

Unlike most bushplanes a stepladder was not required for refuelling. Oil could be topped up from the cockpit, and oil dilution was provided to assist engine starting in cold weather.

Many features were not new and some, unproven, were not welcomed by prospective buyers. The art of design is in the details and the integration of all the elements, and the proof of the pudding would be in the flight tests.

Finally, in August 1947, the Beaver made a first flight in the experienced hands of Russ Bannock (who later became president of DHC). Everyone was happy. George Neal conducted the flight tests required to win a Department of Transport Type Approval.

On wheels in the take-off or landing, the Beaver would clear a 50-foot obstacle in 1000 feet, fully loaded. Floatplane performance was equally gratifying with a 15-second run, typically, to lift off.

Many vintage aeroplanes with enormous wings lightly loaded could take-off with a short run. The difference in the Beaver was an ability to clear obstacles with a useful load. It was the first to qualify for the acronym “STOL” (short take-off and landing).

The coveted order from the Ontario government for 16 aircraft was followed by orders from other provinces. The first commercial sales were to mining companies and charter operators.

With sales overseas, Beavers soon were operating in 63 countries. Activities ranged from forest patrols, fire fighting, ambulance services, VIP travel, the delivery of newspapers from Tokyo, to the “air” delivery of fence posts and phosphate in the Australian outback. Excluding Canada, 14 governments adopted the Beaver. Many of these planes participated in Antarctic explorations. Today, a lake, glacier, and river are named for the intrepid Beaver.

When Bannock demonstrated the Beaver to a search and rescue unit in Alaska, the United States Air Force ordered six; this was followed by orders from the U.S. Army. A substantial importation of aircraft by the United States government set bells ringing in the U.S. aviation industry and resulted in a series of competitions that the Beaver won handily.

Eventually, sales to the U.S. Army accounted for about half of the total production of some 1600 Beaver. In both the Korean and Viet Nam wars, the Beaver was used as a “flying jeep” for local reconnaissance, casualty evacuation, and communications.

Today, the Beaver is unique in remaining, after 50 years, a useful, productive aircraft. Few belong to the original owner and some have flown over 20,000 hours, equivalent to 80 times around the earth. (When the Beaver was originally conceived, a good annual utilization for a bush plane was predicted to be 250 hours per year.)

When production ceased in the ’60s, the demand created a lively cottage industry to rebuild old and damaged Beaver airframes. Concentrated mostly on the west coast where many hundreds of these revered flying machines continue to operate, these “restorations” – with turbine engines, increased payloads, stretched cabins, and avionics worthy of an intercontinental jet transport – are viewed with pride by the original design team.

In 1978 the Beaver was selected by the Canadian Engineering Centennial Board as one of ten outstanding engineering achievements in Canada during the past 100 years.

[The author was responsible for the aerodynamic design of the Beaver.]

Dick Hiscocks (1914-1997)