TYPE: Twin-turboprop airliner.

PROGRAMME: Launched June 1995 as stretch of Series 300; component manufacture began December 1996; engine first test flown in January 1997, mounted on nose of Pratt & Whitney Canada Boeing 720B testbed; roll-out 21 November 1997, first flight (C-FJJA) 31 January 1998; five aircraft participated in the 1,900 hour, 1,400 sortie flight test programme, based at the Bombardier Flight Test Centre in Wichita, Kansas, leading to Transport Canada CAR 525 Amendment 86 certification on 14 June 1999, JAA approval in December 1999 and FAA FAR Pt 25 approval on 8 February 2000. JAA approval for steep approach (5.5^o glideslope) operations at London City Airport achieved 11 October 2001. First delivery (OY-KCA) to SAS Commuter 20 January 2000, followed by service entry 7 February on Copenhagen, Denmark, to Poznan, Poland route. Q400 fleet flight time totalled 154,800 hours and 177.000 cycles by November 2001. Mitsubishi joined programme as risk-sharing partner in October 1995, with responsibility for design, development and manufacture of fuselage and tail sections.

CUSTOMERS: Total of 78 firm orders by 31 March 2003, at which time 71 had been delivered. Launch customer was Great China Airlines (now UNI Airways), which ordered six (since cancelled) in February 1996. US launch customer Horizon Air, which ordered 15 with 15 options, in June 1999, took delivery of its first aircraft on 8 January 2001. First for Changan handed over 27 October 2000. British European (now FlyBE) received first on 23 November 2001; Wideroe deliveries began 16 November 2001. Recent customers include FlyBE, which ordered 17, plus 20 options, on 23 April 2003, for delivery from second quarter 2003.

COSTS: FlyBE order for 17 aircraft, valued at US$362 million (2003). Direct operating cost in US currency, based on 70 passengers over 200 n mile (370 km; 230 mile) stage length: in USA 8.06 cents per seat-mile; in Europe 8.08 cents per seat-kilometre (both 2002).

DESIGN FEATURES: Compared with Q300, fuselage stretched 6.83 m (22 ft 5 in) to seat up to 78. Other new features include engines; propeller; tapered inboard wing section increasing propeller/fuselage clearance to 1.09 m (3 ft 7 in); revised wing/fuselage fairings; ailerons, elevators and fin cap fairing; landing gear; baggage/service doors; upgraded avionics. Airframe designed for crack-free life of 40,000 flight hours/80,000 flight cycles and an economic life of 80,000 flight hours/160,000 flight cycles. Common type rating with Q100/200/300.

STRUCTURE: Generally as for Q100 and Q200. De Havilland Canada manufactures cockpit section and wing and performs final assembly; other participants in programme include AlliedSignal (electrical power system); Goodrich (brakes); Dowty Aerospace (propellers); Menasco (landing gear); Micro Technica (flap system); Mitsubishi (fuselage and tail sections); Parker Bertea Aerospace (hydraulics and fuel system); Pratt & Whitney Canada (engines); Sextant Avionique (avionics system); and Shorts (engine nacelles).

POWER PLANT: Two Pratt & Whitney Canada PW150A turboprops with FADEC, each flat rated to 3,781 kW (5,071 shp) at 37,4^oC, driving Dowty R408 six-blade, slow-turning (1,020 rpm for T-O; 850 rpm cruise) composites propellers giving 15 per cent reduction in T-O rpm and 6 to 19 per cent rreduction in cruise rpm over Q100/300. Fuel capacity 6,526 litres (1,724 US gallons; 1,436 Imp gallons).

ACCOMMODATION: Variety of cabin configurations providing four-abreast seating, with central aisle, for 70 passengers at 84 cm (33 in) pitch. 74 passengers at 79 cm (31 in) pitch, 78 passengers at 76 cm (30 in), or two-class layout for 10 business class passengers at 86 cm (34 in) pitch and 62 economy class passengers at 79 cm (31 in); NVS system standard.

AVIONICS: Prime contractor. Thales.
Comms: Dual VHF nav/com and mode S transponder; solid-state FDR and cockpit voice recorder; ELT antenna.
Radar: Weather radar.
Flight: GPWS, radar altimeter, ADF and DME. Provision for FMS, GPS and TCAS II.
Instrumentation: EFIS employs five 152 x 203 mm (6 x 8 in) LCDs. Optional Flight Dynamics HGS4100 (later HGS4200) head-up guidance system.