de Havilland Canada DHC-7
| de Havilland Canada DHC-7 (Dash 7) | |
|---|---|
|
|
| Type: | Regional airliner |
| Design country: | |
| Manufacturer: | |
| First flight: |
March 27, 1975 |
| Commissioning: |
1978 |
| Production time: |
1978-1988 |
| Number of pieces: |
114 |
The 7-DHC de Havilland Canada , the manufacturer also briefly Dash 7 (Engl. For "Dash 7" called), is a 50-seat regional aircraft . It is STOL capable ( s hort t ake o ff and l anding), i.e. that is, it can fly to airports with short runways.
history
Already in the early 1970s, de Havilland Canada started building a robust turboprop model with a required length of the runway of max. 700 m, high rate of climb for topographically unfavorable airfields and low noise level for airports close to cities. In order to achieve this, the DHC-7 was equipped with wings in the shoulder- wing design, buoyancy aids and four slowly rotating, quiet propeller turbines.
After the maiden flight on March 27, 1975 and the first delivery in January 1978, the model was delivered 113 times by 1988. After that, production was discontinued due to a lack of demand due to the availability of more economical and faster models such as the DHC-8-300 or ATR 72 . Apparently there were too few connections on which both the STOL capabilities of the DHC-7 and its passenger capacity were required. The operation promoted and advertised by de Havilland on transverse runways at larger airports could only be implemented in individual cases. The city airports expected when the aircraft was designed in the early 1970s were only actually built in a few cities. Nevertheless, the type of aircraft is still in use at some difficult-to-fly airfields around the world.
The twin-engine DHC-8 with a similar basic concept, but without the distinctive STOL properties of the DHC-7 , emerged as the successor from the early 1980s .
Versions
There are two versions, the Series 100 as a pure passenger version, and the Series 101 as a cargo / passenger version with a large cargo door on the left side of the fuselage in front of the wing. The project under the type designation DHC-7-300 for a 70-seater model was not implemented due to a lack of demand.
In addition to the civilian versions, there are some military machines, the CC-132 for the Canadian armed forces , a DHC-71R for the Canadian Coast Guard , a version for the Venezuelan Navy and the DHC-7 Ranger as a Canadian maritime reconnaissance version. The RC-7 are converted DHC-7s with extensive reconnaissance equipment of the American armed forces, u. a. used to fight drug crime . A DHC-7 with an observation cockpit attached to the front fuselage is used in Canada to observe drift ice and icebergs.
Construction
- Wing: Shoulder-wing construction with large aspect ratio and large double-slit flaps to increase lift. Relatively small ailerons are supported by spoilers, which are also used as braking aids on the ground.
- Hull: light metal hull with a round cross-section and pressurized cabin
- Tail unit: T- tail unit in all-metal construction
- Landing gear: Retractable nose wheel landing gear, main landing gear retracts forwards into the inner engine nacelles, nose wheel to the rear. (The landing gear flaps of the main landing gear remain open when the landing gear is extended. The rear flaps of the nose landing gear close again to prevent stone chip damage in the landing gear shaft, but open when the aircraft is parked as soon as the hydraulic pressure drops.)
- Engine: 4 × PT6A propeller turbine with 4-blade propellers with low revolutions to reduce noise development (at take-off 1210 / min, during cruise 900-1070 / min)
particularities
- The DHC-7 was (for the operator Tyrolean Airways ) the only commercial aircraft approved for operation at the Altiport Courchevel .
- To reduce lift, the rear flaps of the DHC-7 are automatically retracted after landing. The same thing happens to reduce the air resistance during a go-around maneuver.
Operator in Europe
In Europe the Dash 7 was or is being used by the following operators:
- Adria Airways (Yugoslavia, Slovenia)
- Air Greenland (6 aircraft, on national routes in Greenland)
- British Antarctic Survey (Great Britain)
- British Midland Airways (Great Britain), 1990-1992
- Brymon Airways (UK)
- London City Airways , formerly Eurocity Express, 1987–1990 (Great Britain)
- Maersk Air (Denmark)
- Spantax (Spain), 1978-1981
- Tyrolean Airways (Austria), 1980–1998
- Widerøe's Flyveselskap (Norway)
Military users
-
Yemen
-
Canada
-
United States
- United States Army 10 , 1 O-5A, 2 EO-5B, 5 RC-7B
Incidents
From the first flight in 1975 to October 2019, a total of six DHC-7s were destroyed or irreparably damaged in accidents. A total of 68 people were killed in four of the total losses. Examples:
- On May 9, 1982, an Alyemda DHC-7 ( aircraft registration number 7O-ACK ) crashed into the sea about 2 kilometers from the runway while approaching Aden Airport . Of the 49 inmates, 23 were killed. This was the first total loss of a de Havilland Canada DHC-7.
- On May 6, 1988, a DHC-7 coming from Namsos flew the Widerøe's Flyveselskap (LN-WFN) 8 kilometers from Brønnøysund Airport while approaching Torghatten Mountain . It had flown in with low clouds at too low an altitude. All 36 people on board were killed - this was the worst accident with this aircraft type until October 2019.
Technical specifications
| Parameter | Data |
|---|---|
| Passengers | 50-54 |
| length | 24.6 m |
| span | 28.4 m |
| height | 8 m |
| Wing area | 79.9 m² |
| Width of the cabin | 2.6 m |
| Length of the cabin | 12 m |
| Cabin height | 1.9 m |
| Takeoff mass | 21,319 kg |
| Cruising speed | 400 km / h |
| Max. Altitude | 6400 m (without passengers up to 7600 m) |
| Range | 1550-2200 km |
| Engines | four propeller turbines Pratt & Whitney Canada PT6A-55 (904 kW takeoff power each) |
| Fuel capacity | 4500 kg in four wing tanks |
See also
Web links
- The Dash 7 Homepage (Engl.)
- Dash 7 World Archive (Engl.)
Individual evidence
- ↑ rzjets: Spantax (English), accessed on September 26, 2019.
- ^ "Canadian Aerospace - Background - DeHavilland Canada Dash 7." Canadian American Strategic Review via Archives , October 11, 2009. Retrieved October 18, 2009.
- ↑ DHC-7 accident statistics , Aviation Safety Network (English), accessed on October 21, 2019.
- ^ Accident report DHC-7 7O-ACK , Aviation Safety Network (English), accessed on October 21, 2019.
- ^ Accident report DHC-7 LN-WFN , Aviation Safety Network (English), accessed on October 21, 2019.