De Havilland Canada was established at Downsview in Toronto in 1928 as a subsidiary of the British parent. What made it significant was that it stopped building British designs and started building for Canadian conditions — and discovered that the rest of the world had the same conditions.
The problem it solved
Canada north of the settled belt has no runways. It has lakes, gravel bars, tundra and short clearings. Serving that country required aircraft that could take off and land in very little distance, carry a useful load, operate on floats or skis, and be repaired by whoever was there.
Short takeoff and landing — STOL — became the company's entire identity.
The aircraft
DHC-2 Beaver (1947). The definitive bush aircraft. Designed after consulting Canadian bush pilots directly about what they actually needed, which turned out to be doors big enough for an oil drum and the ability to get off a short lake fully loaded. Over 1,600 were built, and hundreds are still flying.
DHC-3 Otter (1951). A larger Beaver, same philosophy.
DHC-4 Caribou (1958). A twin-engine STOL military transport, widely used in Vietnam by the US Army for its ability to operate from short unprepared strips.
DHC-6 Twin Otter (1965). The most commercially successful of them all — a twin-turboprop nineteen-seater that serves island hops, Arctic communities, Antarctic research and mountain airstrips. Production restarted in the 2000s after decades, because nothing had replaced it.
DHC-7 Dash 7 (1975). A four-engine STOL airliner, quiet enough for city-centre airports. Commercially disappointing, technically remarkable — it is the aircraft that made London City Airport viable.
DHC-8 Dash 8 (1984). The commercial breakthrough. A twin turboprop regional airliner that has sold over a thousand units. Porter flies the Q400 from Billy Bishop, which exists as an airport largely because DHC aircraft can use it.
The ownership carousel
The company's corporate history is almost as eventful as its products. British-owned until nationalised by the Canadian government in 1974. Sold to Boeing in 1986. Sold by Boeing to Bombardier in 1992. The Dash 8 programme sold by Bombardier to Longview Aviation in 2019, which revived the De Havilland Canada name.
Longview also holds the type certificates for the older piston and turboprop designs, and has restarted Twin Otter production.
Why it matters
De Havilland Canada is the clearest example of a Canadian industrial success built by solving a Canadian problem well rather than by competing on someone else's terms. The Beaver and the Twin Otter opened the Canadian North, and then sold to every country with terrain that punishes conventional aircraft.
The Beaver was named one of Canada's top engineering achievements of the twentieth century, and it is on a postage stamp. It is one of the very few aircraft that is also a national symbol.