De Havilland Canada Part 2
De Havilland Canada’s ‘flying pick-up trucks’ had made the company and its products a household name in the frozen north of Canada, and the then-new US state of Alaska, by the 1960s. Many isolated communities were almost entirely dependent on transport links provided by the DHC-2 Beaver and its larger sibling the DHC-3 Otter. When Pratt & Whitney Canada, maker of the Wasp radial (piston) engine on the Beaver and Otter, began producing a small turbine engine, named the PT6, the designers at DHC recognized an opportunity. They started working on a twin-engine STOL (short takeoff and landing) aircraft, powered by two PT6 turboprop engines, as a larger and more powerful addition to the stable, dubbing it the DHC-6 Twin Otter.
The PT6 engine proved to be a timeless design, arguably the best turbine engine ever built. Its pairing with the DHC-6 was a symbiotic relationship, as the ‘Twotter’ (to use its popular nickname) became ubiquitous and long-lived — a true classic that has refused to die despite its corporate parents’ best efforts to kill it off.
The two-ton pickup truck
The combination of a robust, simple structure, ease of maintenance, the ability to carry 2,150 lbs of payload, the security of two reliable engines, and excellent short-field performance, made the DHC-6 Twin Otter an instant success.
The ‘Twotter’ could be delivered from the factory with conventional fixed tricycle landing gear, floats, or skis. While the far north of Canada and Alaska were the original intended markets, operators everywhere have found it to be the ideal ‘bush’ aircraft. The type has seen use on every continent, including Antarctica, where it provides year-round support to the scientific expeditions based there.
Such is the versatility of the Twin Otter, many commuter airlines began using it as well. Capable of taking off with a full payload from runways as short as 3,000 ft (914 m) the DHC-6 offered options that hadn’t existed previously. When the Walt Disney Corporation opened its second resort, Disney World, in Orlando, Florida (the original Disneyland is in California), a private airport was included, serviced by Twin Otters.
Amazing versatility
In addition to its versatility with any type of landing gear configuration and in all environments, the ‘Twotter’ requires minimal ground support and maintenance. Users are as disparate as Trans Maldivian Airways, whose fleet of 50-plus DHC-6 floatplanes shuttle passengers between the main international airport at Hulhulé, near the Maldivian capital Malé, and luxury resorts on tropical islands in the Maldives archipelago; at the other extreme, approximately 40 Twin Otters of Canadian-owned Kenn Borek Air operate at both the South Pole and Arctic region, on skis.
Elsewhere, ‘Twotters’ work hard for a living in such corners of the world as the Himalayas (with Yeti Airlines of Nepal), the highlands of Papua New Guinea, Australia’s Great Barrier Reef, the Caribbean, the Outer Hebrides (where Twin Otters land on the beach at low tide), and Chile’s South Shetland Islands. There is hardly a country where DHC-6s don’t provide vital air links, more than 50 years since the prototype first flew. Testifying to the type’s successful design is the total of 844 examples of the DHC-6 Series 100, 200 and 300 built between 1965 and 1988.
Foray into four engines
Flush with the Twin Otter’s success, DHC’s designers proceeded to build a bigger airplane. The resulting DHC-7 had the same STOL characteristics as its smaller sibling, but with four turboprop engines (again the trusty PT6), a pressurized fuselage, and a capacity of 50 passengers. The much larger ‘Dash 7’ was optimized to operate out of very short runways while maintaining a low noise profile.
As with all of DHC’s designs, the new aircraft performed very well. But its market was a niche one at best, and the Dash 7 entered production at a time when oil prices were rising rapidly. With four engines, maintenance costs were high too. Many other established types such as the ‘Convairliners’ and Hawker Siddeley (Avro) 748 were also fighting for market share, so the DHC-7 proved unsuccessful, with only 113 being built.
The Dash 7 did, however, fit a niche where operations were permitted from restricted runways, such as at London City Airport (located by the Thames River in close proximity to the banking hub), or mountain strips at Colorado’s ski resorts and Kapalua Airport on Maui, Hawaii.
When better-performing larger aircraft became increasingly available, the Dash 7 faded away, with fewer than 20 remaining in service worldwide.
The final design
Realizing that the Dash 7 was overkill in many respects, DHC went back to the drawing board to design a 30–40-seat commuter aircraft that could replace the world’s aging fleets. The same basic layout as the Dash 7 was employed, but with a more economical two engine configuration.
The DHC-8 (a.k.a. ‘Dash 8’) incorporated many lessons learnt during the 1970s. Debuting with the Canadian regional airline NorOntair in 1984, the type proved to be very popular, especially as its cruise speed was not much less than that of competing jet aircraft. The Dash 8–200 with 37 passengers soon grew to the 50 seat Dash 8–300 model. This was in turn superseded by the 80 seat -400 which incorporated an active noise and vibration suppression system (NVS) to bring the cabin and exterior noise footprint to levels of competing pure-jet types. The latter improvements prompted a name change, with the upgraded aircraft being later designated the Q-Series (‘Q’ for quiet).
Corporate troubles
Despite the success of their designs, the initially government-owned De Havilland Canada Corporation had a turbulent history. When aerospace giant Boeing acquired the Canadian company after it was privatized in the 1980s, assurances were given that the DHC-6 and -7 lines would be continued; but this was not honored, with production of both types halted soon afterward. Many of the jigs and specialized equipment were also scrapped. Consequently, the Dash 8 was the only original DHC type that remained in production during Boeing’s ownership.
The issue became ugly when Boeing lost out to Airbus on a lucrative aircraft order for Air Canada (then also government-owned). De Havilland Canada was put up for sale and acquired by Montreal-based Bombardier Aerospace. The Dash 8 regional turboprop remained in production, now renamed the Q series as improvements were incorporated and with Bombardier seeking to re-brand the line.
The Twotter endures and is reborn
Despite the halt in production and lack of support by Bombardier, more than 600 of the original Twin Otters remained in use. Many companies came to the fore with support for the aircraft, which had steadily appreciated in value. A serviceable ‘Twotter’ now commanded more than three times its original price when newly built.
Viking Air of Sidney, British Columbia, Canada saw a lucrative niche and became a major supplier of parts for older Twin Otters. With original jigs no longer available, parts were digitally scanned so they could be reproduced accurately. The business proved profitable, and in 2005 Viking purchased the rights from Bombardier to manufacture spares for the DHC-6. This was followed by the acquisition in 2006 of all the original De Havilland Canada designs, from the DHC-1 Chipmunk through to the DHC-7. The first Viking Twin Otter, named the Series 400, flew in 2010, since when more than 80 have been delivered, with production comprising approximately 18 units per year.
The Twin Otter’s resurrection must have been successful, as Viking’s parent company, Longview Capital, has since acquired from Bombardier the rights to the Q400 (DHC-8) too, thus bringing the current range of De Havilland Canada aircraft under the umbrella of one corporate entity again. It would be tempting, if not realistic, for enthusiasts to hope that not only the ‘Twotter’ but other classic DHC designs could be produced again.
The first part of this column on De Havilland Canada is here. Thank you all for reading and following these posts. I hope you enjoyed reading them half as much as I did writing them. All the very best to all of my readers for the holiday season and I hope 2021 proves to be a more cheerful and optimistic year.
