The DHC-7, popularly known as the Dash 7, is a short haul four-engine turboprop short take-off and landing passenger aircraft seating 48 passengers and powered by four PT6A-50 engines. Designed and built by De Havilland Canada in Toronto, the Dash-7 was part of a family of aircraft specifically developed for use in the rough Canadian wilderness and capable of facing the wide ranging weather conditions.
The type was offered as a regional airliner with greater capacity than the DHC-6 Twin Otter to compete with twin turboprop aircraft such as the Convair 580 and Hawker Siddeley 748. With the new noise restrictions introduced during the 1970s, huge consideration was given to the use of oversized propellers, geared to reduce rotation speeds without any reduction in thrust.
This was an important attraction forthe type as its low levels of external noise and ability to perform steep approaches and departures minimised its noise footprint in the vicinity of the airport.
The prototype (C-GNBX-X) was flown for the first time on 27th March 1975 with the first production aircraft flying in May 1977 and the first delivery being made in February 1978.
The first operator of the Dash 7 was Rocky Mountain Airways of Denver, who took delivery of that first aircraft on 3rd February 1978. Rocky Mountain had always provided tourist flights to resort airports, often those with relatively short runways and high airfield elevations. One of the most successful of routes was from Denver directly into Avon Airport in Colorado which was controlled by Rocky Mountain Airways and which provided easy access to the local ski resort at Vail.
The main variant produced was the Series 100 regional airliner, the other variant being the Series 150 which offered additional fuel capacity and increased take-off weight among other changes.
The Series 100 came in two sub-variants; the DHC-7-102 passenger version and -103 combi with an enlarged cargo door.
A total of 113 were built by De Havilland Canada and the type saw service with the Canadian Forces (CC-132 VIP transport aircraft operated in West Germany), United States Army (EO-5C / RC-7 supporting the Airborne Reconnaissance Low programme) and the Venezuelan Navy.
The Dash 7 met with limited commercial success as the feeder airliner requirements were not STOL critical and the features on offer were not considered as so attractive. Those airport that did require acute STOL capability opted for the Twin Otter whilst others simply extended their runways to accommodate larger, more cost effective aircraft.
The more conventional twin-engine design arrived in 1978 with the first flight of the Dash 8 which still continues to operate today with exceptional success. De Havilland Canada ceased production of the Dash 7 in 1988, and the type certificate was sold to Viking Air of British Columbia in 2005.
|Powerplant||Four 1,120shp Pratt & Whitney PT6A-50 turboprop engines|
|Span||93 ft 0 in|
|Maximum Weight||44,000 lb|
|Capacity||Two flight crew, two cabin crew and up to 48 passengers dependent on cabin layout|
|Maximum Cruise||266 mph|
|Range||795 miles (50 passengers, IFR reserves)|
Variants & Number built
|Prototypes - 2 built|
|DHC-7-100||Production variant with a maximum of 54 passengers (43,000 lb max weight)|
|DHC-7-101||Passenger/cargo variant with a maximum 50 passengers and a forward cargo door|
|DHC-7-102||Production variant with a maximum of 54 passengers (44,000 lb max weight)|
|DHC-7-103||Passenger/cargo variant with a maximum of 50 passengers and forward cargo door (44,020 lb max weight)|
|DHC-7-110||DHC-7-102 certified for use in the United Kingdom|
|DHC-7-111||DHC-7-103 certified for use in the United Kingdom|
|DHC-7-150||Version with higher max weight, increased fuel capacity|
|DHC-7-150 IR||One series 150 for Transport Canada for ice/pollution patrols of the Canadian Arctic|
|Total production||113 aircraft|
No longer in production, the type remains in service in modest numbers with 21 being registered in Canada and 12 in the United States.