Bombardier Dash 8 - Design and Development

Design and Development

In the 1970s, de Havilland Canada had invested heavily in its Dash 7 project, concentrating on STOL and short-field performance, the company's traditional area of expertise. Using four medium-power engines with large four-bladed propellers resulted in very low noise levels which, combined with its excellent STOL characteristics, made the Dash 7 suitable for operating from small in-city airports, a market DHC felt would be compelling. However, only a handful of air carriers employed the Dash 7, as most regional airlines were more interested in operational costs than short-field performance.

In 1980, de Havilland responded by dropping the short-field performance requirement and adapting the basic Dash 7 layout to use only two, more powerful engines. Its favoured engine supplier, Pratt & Whitney Canada, developed the new PW100 series engines for the role, more than doubling the power from its PT6. Originally designated the PT7A-2R engine, it later became the PW120. When the Dash 8 rolled out on April 19, 1983, more than 3,800 hours of testing had been accumulated over two years on five PW100 series test engines. Certification of the PW120 followed in late 1983.

Distinguishing features of the Dash 8 design are the large T-tail intended to keep the tail free of prop wash during takeoff, a very high aspect ratio wing, the elongated engine nacelles also holding the rearward-folding landing gear, and the pointed nose profile. First flight was on June 20, 1983, and the airliner entered service in 1984 with NorOntair. In 1984, Piedmont Airlines, formerly Henson Airlines, was the first US customer for the Dash 8.

The Dash 8 design has better cruise performance than the Dash 7, is less expensive to operate and much less expensive to maintain, due largely to having only two engines. The Dash 8 has the lowest cost per passenger mile of any regional airliner of the era. It was a little noisier than the Dash 7 and could not match the STOL performance of its earlier DHC forebears, although it was still able to operate from small airports with 3,000 ft (910 m) runways, compared to the 2,200 ft (670 m) required by a fully loaded Dash 7.

In April 2008, Bombardier announced that production of the Classic versions (Series 100, 200, 300) would be ended, leaving the Series 400 as the only Dash 8 still in production. 671 Dash 8 Classics were produced, the last one delivered to Air Nelson in May 2008.