De Havilland Canada Dash 7 The de Havilland Canada DHC - 7 , popularly known as the Dash 7 , is a turboprop - powered regional airliner with STOL capabilities . It first flew in 1975 and remained in production until 1988 when the parent company , de Havilland Canada , was purchased by Boeing and was later sold to Bombardier . Bombardier sold the aircraft design ( type certificate ) to Viking Air in 2006 . Design and development . In the 1960s , de Havilland Canada was already well known worldwide for their series of high - performance STOL aircraft , notably the very popular DHC - 6 Twin Otter . However , these aircraft were generally fairly small and served outlying routes , as opposed to the busier regional airliner routes which were already well served by larger , higher - performance turboprop aircraft such as the Fokker F27 , Fairchild F - 27 , Convair 580 and 600 , and Hawker Siddeley 748 . The de Havilland Canada company felt they could compete with these designs in a roundabout way . With their excellent STOL performance , their designs could fly into smaller airports located in city centres and smaller , outlying , more austere airports having runways that the other aircraft could not easily use ( unpaved , unimproved ) . The original specification called for a 40 - passenger aircraft with a fairly short range of 200 statute miles , operating from runways only . With new noise restrictions coming into effect throughout the 1970s , an aircraft tailored for this role would also have to be very quiet . To meet this restriction , the new design used oversized propellers geared to spin at a slower speed than normal ; much of the sound from a propeller is generated at the tips which are spinning near the speed of sound , and therefore , by reducing the RPM , this noise is reduced substantially . The Dash 7 often landed with only 900 rpm , and took off at only 1 , 210 . In other respects , the new DHC - 7 was essentially a larger , four - engine version of the Twin Otter : the general layout remained similar , with a high aspect ratio high - mounted wing , most details of the cockpit and nose profile . Changes included the addition of cabin pressurization ( requiring a switch to a fuselage with a circular cross - section ) , landing gear that folded forward into the inner engine nacelles and a large T - tail intended to keep the elevator clear of the propwash during takeoff ( the Twin Otter ' s empennage was a cruciform arrangement ) . The Twin Otter incorporated " flaperon s " that drooped the ailerons as part of the flaps , but these were not included in the Dash 7 due to weight and complexity . Instead , the ailerons were reduced in size to allow more flap area , and were augmented with two sets of roll spoilers , or " spoileron s " . The inboard roll spoilers operate at all speeds while the outboard roll spoilers only operate at speeds less than 130KIAS to allow for more roll control at slower speeds . Upon touchdown , both the inboard and outboard roll spoilers extend in unison to aid in destroying lift created by the wing . Each wing also includes two ground spoilers which only extend on touchdown . Most of the trailing edge is spanned by a complex double Fowler flap arrangement for high lift at low speed . During a typical STOL landing , flaps are selected to the 45° position allowing for steeper descents and slower approach speeds . Depending on weight , the V speed with flaps at 45° is between 70 - 85 knots . On touchdown , through " squat switches " in the main gear , the flaps automatically retract to the 25° position and thus reduce lift once on the runway producing better braking performance . The flaps also retract to 25° when engine power is increased during a go - around procedure . The four - engine layout aids lift at low speeds due to the wide span of the propellers blowing air over the wing ( " propwash " ) . When reverse thrust is selected on landing , the props reverse pitch , push air forward and slow the aircraft very effectively along with the anti - skid wheel brakes . More importantly , if an engine fails , the asymmetric thrust is much less than on a twin - engine layout , thereby increasing safety and allowing for a lower V ( minimum control speed ) with an engine inoperative . Operational history . Development started in 1972 and the prototype first flew on March 27 , 1975 . Testing went smoothly , and the first delivery took place to Rocky Mountain Airways on February 3 , 1978 . The Dash 7 enabled Rocky Mountain Airways to operate scheduled passenger air service from Denver into the Avon STOLport in Colorado which was controlled by the airline . The Avon STOLport was located in a mountain valley in close proximity to the Vail ski resort . Another close - in ski resort airfield served by Rocky Mountain Airways with Dash 7 flights from Denver was Steamboat Springs Airport in Colorado . With a relatively short runway length of 4 , 452 feet and an airfield elevation of 6 , 882 feet , the Dash 7 was well suited for operations from this airport located in the Rocky Mountains . The Kapalua Airport on the island of Maui in Hawaii was constructed specifically with Dash 7 operations in mind . According to State of Hawaii historical records , Hawaiian Airlines built this airfield and then initiated scheduled passenger flights with new Dash 7 propjets on March 1 , 1987 . The airline owned this private airport , which is also known as Kapalua - West Maui Airport , until 1993 when it was acquired by the State of Hawaii . The 3000 foot runway length at Kapalua was well suited for Dash 7 operations . The three letter code for the Kapalua Airport , JHM , stands for John Henry Magoon who was President of Hawaiian Airlines when the airfield and terminal were constructed by the air carrier . Kapalua is currently served by Island Air with Dash 8 propjets . One hundred Dash 7 turboprops were delivered by 1984 , when the production line was put on hold in favour of the Dash 8 . Another 13 were delivered between 1984 and 1988 , when the production lines were removed when Boeing bought the company . The original Series 100 represents the vast majority of the aircraft delivered , and came in two models ; the - 102 passenger version and - 103 combi with an enlarged cargo door . These were followed by the Series 110 which met British CAA requirements , including the - 110 and - 111 , and finally the Series 150 which included additional fuel tankage and an improved interior in the - 150 and - 151 . There were plans for a Series 200 with the new PT6A - 50 / 7 engines which improved hot - and - high power , but these plans were shelved when Boeing ended production of the design . The mixture of features on the Dash 7 met with limited commercial success . Most commuter airline turboprop operators used the aircraft as feederliners into large airports , where the STOL performance wasn ' t considered important . In comparison to other feederliners , the Dash 7 ' s four engines required twice the maintenance of a twin - engine model , thereby driving up operational costs . Finally , those airports that did require a high performance STOL operation were generally small and well served by the Twin Otters ; had the airport needed a larger plane to serve its customer base , they would have built larger runways . One exception to this was operations at London City Airport ( LCY ) which , upon opening in 1987 , was capable of handling few other aircraft types besides the Dash 7 due to its relatively short runway as well as steep approach . The runway at London City Airport was subsequently lengthened and now accommodates jet operations including scheduled airline flights operated with Airbus A318 and British Aerospace BAe 146 jetliners . The Dash 7 also gained a number of military orders . The first of these was for two aircraft for the Canadian Armed Forces , who needed them to transport high ranking passengers and freight around Europe . These aircraft received the CF designation CC - 132 and were delivered to No . 412 Squadron at Lahr , in West Germany . The United States Army operates several Dash 7 aircraft as surveillance platforms with the designation EO - 5C ( RC - 7B before 2004 ) under the Airborne Reconnaissance Low program . Transport Canada operates a single DHC - 7 - 150IR aircraft to conduct maritime surveillance , pollution and ice patrols as part of the Transport Canada National Aerial Surveillance Program ( N . A . S . P . ) . The aircraft ' s home base is Ottawa , Ontario , Canada . During the summer months this aircraft conducts patrols throughout the Canadian Arctic , Alaska and Greenland . During the fall and winter months this aircraft conducts patrols of the Great Lakes and east or west coasts of Canada as required . The design of a much more " conventional " twin - engine design commenced at de Havilland in 1978 , resulting in the extremely popular Dash 8 . The DHC - 7 production line eventually delivered 113 , of which six have been lost and one scrapped . Many of the rest remain in service . Accidents and incidents . The de Havilland Canada DHC - 7 has been involved in six accidents ( and 10 incidents overall ) with a total of 68 fatalities . Operators . Airline and other operators . As of April 27 , 2012 , a total of 47 Dash 7 aircraft ( all variants ) remain in airline and other services . Other civilian operators . The British Antarctic Survey ( BAS ) operates a single Dash 7 in support of its research program in Antarctica . The aircraft undertakes regular shuttle flights between either Stanley on the Falkland Islands , or Punta Arenas in Chile , and the Rothera Research Station on Adelaide Island . It also operates to and from the ice runway at the Sky Blu Logistics Facility on the Antarctic mainland . A single DHC - 7 150IR is owned and operated by Transport Canada conducting coastal pollution and ice patrols across the Canadian Arctic .