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 comparatively lower 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 is a little noisier than the Dash 7 and cannot match the STOL performance of its earlier DHC forebears, although it is 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. A total of 671 Dash 8 classics were produced, the last one delivered to Air Nelson in May 2008.
Bombardier proposed development of a 90-seat stretch of the Q400 with two plug-in segments, called the Q400X project, in 2007. In response to this project, as of November 2007, ATR was studying a 90-seat stretch.
In June 2009, Bombardier commercial aircraft president Gary Scott indicated that the Q400X will be "definitely part of our future" for possible introduction in 2013–14, although he has not detailed the size of the proposed version or committed to an introduction date.
As of July 2010, Bombardier's vice president, Phillipe Poutissou made comments explaining the company was still studying the prospects of designing the Q400X and talking with potential customers. At the time, Bombardier was not as committed to the Q400X as it had been previously. As of May 2011, Bombardier was still strongly committed to the stretch, but envisioned it as more likely as a 2015 or later launch, complicating launch date matters were new powerplants to come online in 2016 from GE and PWC. As of February 2012, Bombardier was still studying the issue, however as of 2011, launch date is no longer targeted for the 2014 range. At least a three-year delay was envisioned.
In October 2012, a joint development deal with a government-led South Korean consortium was revealed, to develop a 90-seater turboprop regional airliner, targeting a 2019 launch date. The consortium would include Korea Aerospace Industries and Korean Air Lines.
- DHC-8-100 series
- E-9A Widget
- E-9A Widget
- DHC-8-200 Series
- DHC-8-300 Series
- DHC-8-300 MSA
- DHC-8 MPA-D8