de Havilland Canada DHC-6 Twin Otter

From Wikipedia, the free encyclopedia
  (Redirected from Twin Otter)
Jump to navigation Jump to search

DHC-6 Twin Otter
WinAir De Havilland Canada DHC-6-300 Twin Otter Breidenstein.jpg
A Winair DHC-6 Twin Otter landing at St Barthelemy Gustaf III Airport.
Role Utility aircraft
Manufacturer de Havilland Canada
Viking Air
First flight 20 May 1965
Introduction 1966
Status In production[1]
Produced 1965–1988 (Series 100-300)
2008–present (Series 400)
Number built Oct 2017: 967
(844 DHC, 123 Viking)[2]
Unit cost
US$680,000 (1972)[3]
US$6.5 million (2017)[4]
Developed from de Havilland Canada DHC-3 Otter
Developed into de Havilland Canada Dash 7

The de Havilland Canada DHC-6 Twin Otter, currently marketed as the Viking Air DHC-6 Twin Otter, is a Canadian 19-passenger STOL (Short Takeoff and Landing) utility aircraft developed by de Havilland Canada and currently produced by Viking Air. The aircraft's fixed tricycle undercarriage, STOL capabilities, twin turboprop engines and high rate of climb have made it a successful commuter passenger airliner as well as a cargo and medevac aircraft. In addition, the Twin Otter has been popular with commercial skydiving operations, and is used by the United States Army Parachute Team and the United States Air Force's 98th Flying Training Squadron.

Design and development[edit]

Aerovías DAP DHC-6 Series 300 at Puerto Williams
A Twin Otter making a normal landing approach in Queensland
First flight of the Series 400 technical demonstrator by Viking Air at Victoria Airport, October 1, 2008

Development of the aircraft began in 1964, with the first flight on May 20, 1965. A twin-engine replacement for the single-engine DHC-3 Otter retaining DHC's renowned STOL qualities, its design features included double-slotted trailing-edge flaps and ailerons that work in unison with the flaps to boost STOL performance. The availability of the 550 shp (410 kW) Pratt & Whitney Canada PT6A-20 turboprop in the early 1960s made the concept of a twin more feasible. To bush operators, the improved reliability of turboprop power and the improved performance of a twin-engine configuration made it an immediately popular alternative to the piston-powered Otter which had been flying since 1951.

The first six aircraft produced were designated Series 1, indicating that they were prototype aircraft. The initial production run consisted of Series 100 aircraft, serial numbers seven to 115 inclusive. In 1968, Series 200 production began with serial number 116. Changes made at the beginning of Series 200 production included improving the STOL performance, adding a longer nose that was equipped with a larger baggage compartment (except for aircraft fitted with floats), and fitting a larger door to the rear baggage compartment. All Series 1, 100, and 200 aircraft and their variants (110, 210) were fitted with the 550-shaft-horsepower PT6A-20 engines.

In 1969, the Series 300 was introduced, beginning with serial number 231. Both aircraft performance and payload were improved by fitting more powerful PT6A-27 engines. This was a 680 hp (510 kW) engine that was flat-rated to 620 hp (460 kW) for use in the Series 300 Twin Otter. The Series 300 proved to be the most successful variant by far, with 614 Series 300 aircraft and their subvariants (Series 310 for United Kingdom operators, Series 320 for Australian operators, etc.) sold before production in Toronto by de Havilland Canada ended in 1988.

New production[edit]

After Series 300 production ended, the remaining tooling was purchased by Viking Air of Victoria, British Columbia, which manufactures replacement parts for all of the out-of-production de Havilland Canada aircraft. On February 24, 2006, Viking purchased the type certificates from Bombardier Aerospace for all the out-of-production de Havilland Canada aircraft (DHC-1 through DHC-7).[5] The ownership of the certificates gives Viking the exclusive right to manufacture new aircraft.

On July 17, 2006, at the Farnborough Air Show, Viking Air announced its intention to offer a Series 400 Twin Otter. On April 2, 2007, Viking announced that with 27 orders and options in hand, it was restarting production of the Twin Otter, equipped with more powerful Pratt & Whitney Canada PT6A-34 engines.[6] As of November 2007, 40 firm orders and 10 options had been taken and a new final assembly plant was established in Calgary, Alberta.[7][8] Zimex Aviation of Switzerland received the first new production aircraft, serial number 845, in July 2010.[9][10] By mid-2014, Viking had built 55 new aircraft at its Calgary facility. The production rate as of summer 2014 was about 24 aircraft per year. In April 2015, Viking announced a reduction of the production rate to 18 aircraft per year.[11] On June 17, 2015, Viking further announced a partnership with a Chinese firm, Reignwood Aviation Group. The group will purchase 50 aircraft and become the exclusive representatives for new Series 400 Twin Otters in China.

Major changes introduced with the Series 400 include Honeywell Primus Apex fully integrated avionics, deletion of the AC electrical system, deletion of the beta backup system, modernization of the electrical and lighting systems, and use of composites for nonload-bearing structures such as doors.[12]

The 100th Series 400 (MSN 944) was displayed at the July 2017 EAA AirVenture Oshkosh, 38% are operated as regional airliners, 31% in military aviation or special missions, 26% in industrial support and 5% in private air charter; 70 are on regular landing gear wheels, 18 are configured as straight or amphibious floatplanes, 10 have tundra tires and 2 have wheel skis.[13]

Operational history[edit]

Maldivian DHC-6 Twin Otter water landing
de Havilland Canada DHC-6 Twin Otter on Beechey Island at seamen's graves of John Franklin expedition (Nunavut, Canada) circa 1997. Note the tundra tires.
Twin Otter daily scheduled service between Glasgow (Scotland) and Barra Airport. Barra Airport's runway is on a sand beach.

Twin Otters could be delivered directly from the factory with floats, skis, or tricycle landing gear fittings, making them adaptable bush planes for remote and northern areas. Areas including Canada and the United States, (specifically Alaska) had much of the demand. Many Twin Otters still serve in the far north, but they can also be found in Africa, Australia, Asia, Antarctica, and other regions where bush planes are the optimum means of travel. Their versatility and maneuverability have made them popular in areas with difficult flying environments such as Papua New Guinea. In Norway, the Twin Otter paved the way for the network of short-field airports, connecting rural areas with larger towns. The Twin Otter showed outstanding reliability, and remained in service until 2000 on certain routes. Widerøe of Norway was, at one time, the world's largest operator of Twin Otters. During one period of its tenure in Norway, the Twin Otter fleet achieved over 96,000 cycles (take-off, flight, and landing) per year.[citation needed]

A number of commuter airlines in the United States got their start by operating Twin Otters in scheduled passenger operations. Houston Metro Airlines (which later changed its name to Metro Airlines) constructed their own STOLport airstrip with a passenger terminal and maintenance hangar in Clear Lake City, Texas, near the NASA Johnson Space Center. The Clear Lake City STOLport was specifically designed for Twin Otter operations. According to the February 1976 edition of the Official Airline Guide, Houston Metro operated 22 round-trip flights every weekday at this time between Clear Lake City (CLC) and Houston Intercontinental Airport (IAH, now Houston George Bush Intercontinental Airport) in a scheduled passenger airline shuttle operation.[14] Houston Metro had agreements in place for connecting passenger feed services with Continental Airlines and Eastern Airlines at Houston Intercontinental, with this major airport having a dedicated STOL landing area at the time specifically for Twin Otter flight operations. The Clear Lake City STOLport is no longer in existence.

The Walt Disney World resort in Florida was also served with scheduled airline flights operated with Twin Otter aircraft. The Walt Disney World Airport (WDS), also known as the Lake Buena Vista STOLport, was a private airfield constructed by the Walt Disney Company with Twin Otter operations in mind. In the early 1970s, Shawnee Airlines operated scheduled Twin Otter flights between the Disney resort and nearby Orlando Jetport (MCO, now Orlando International Airport), as well as to Tampa International Airport (TPA). This service by Shawnee Airlines is mentioned in the "Air Commuter Section" of the Sept, 6, 1972 Eastern Air Lines system timetable as a connecting service to and from Eastern flights.[15] This STOL airfield is no longer in use.

Another commuter airline in the U.S., Rocky Mountain Airways, operated Twin Otters from the Lake County Airport in Leadville, CO. At an elevation of 9,927 feet above mean sea level, this airport is the highest airfield in the U.S. ever to have received scheduled passenger airline service, thus demonstrating the wide-ranging flight capabilities of the Twin Otter. Rocky Mountain Airways went on to become the worldwide launch customer for the larger, four-engine de Havilland Canada DHC-7 Dash 7 STOL turboprop, but continued to operate the Twin Otter, as well.

Larger scheduled passenger airlines based in the United States, Canada, Mexico, the Caribbean and Australia, particularly jetliner operators, also flew Twin Otters, with the aircraft providing connecting feeder service for these airlines. Jet aircraft operators which also flew the Twin Otter included Aeronaves de Mexico, Air BC, Alaska Airlines, ALM Antillean Airlines, Ansett Airlines, Cayman Airways, Frontier Airlines (1950-1986), LIAT, Norcanair, Nordair, Ozark Air Lines, Pacific Western Airlines, Quebecair, South Pacific Island Airways, Time Air, Transair (Canada), Trans Australian Airlines (TAA), Wardair Canada and Wien Air Alaska.[16][17] In many cases, the excellent operating economics of the Twin Otter allowed airlines large and small to provide scheduled passenger flights to communities that most likely would otherwise never have received air service.

Twin Otters are also a staple of Antarctic transportation.[18] Four Twin Otters are employed by the British Antarctic Survey on research and supply flights, and several are employed by the United States Antarctic Program via contract with Kenn Borek Air. On April 24–25, 2001, two Twin Otters performed the first winter flight to Amundsen–Scott South Pole Station to perform a medical evacuation.[19][20][21][22] On June 21–22, 2016, Kenn Borek Air's Twin Otters performed the third winter evacuation flight to Amundsen–Scott South Pole Station to remove two people for medical reasons.[23]

The Argentine Air Force has used the Twin Otter in Antarctica[24] since the 1970s, with at least one of them deployed year-round at Marambio Base.[25] The Chilean Air Force has operated the type since 1980, usually having an example based at Presidente Frei Antarctic base of the South Shetland islands.

Air Greenland uses one of its Twin Otters for winter supply flights to the Summit Camp polar research station.

As of August 2006, a total of 584 Twin Otter aircraft (all variants) remain in service worldwide. Major operators include: Libyan Arab Airlines (16), Maldivian Air Taxi (22), Trans Maldivian Airways (23), Kenn Borek Air (42)[26] and Scenic Airlines (11). Some 115 airlines operate smaller numbers of the aircraft including Yeti Airlines in Nepal, Malaysia Airlines (which uses the Twin Otter exclusively for passenger and freight transportation to the Kelabit Highlands region in Sarawak), and in the United Kingdom, the FlyBe franchise operator Loganair which uses the aircraft to service the island of Barra in the Hebrides islands. This daily scheduled service is unique as the aircraft lands on the beach and the schedule is partly influenced by the tide tables. Trials in Barra with heavier planes than the Twin Otter, like the Short 360, failed because they sank in the sand. The Twin Otter is also used for landing at the world's shortest commercial runway on the Caribbean island of Saba, Netherlands Antilles.

The Twin Otter has been popular with commercial skydiving operations. It can carry up to 22 skydivers to over 17,000 ft[27][28] (a large load compared to most other aircraft in the industry); presently, the Twin Otter is used in skydiving operations in many countries. The United States Air Force operates three Twin Otters for the United States Air Force Academy's skydiving team.

On 26 April 2001, the first ever air rescue during polar winter from the South Pole occurred with a ski-equipped Twin Otter operated by Kenn Borek Air.[29][30][31]

On September 25, 2008, the Series 400 Technology Demonstrator achieved "power on" status in advance of an official rollout.[32][33] First flight of the Series 400 technical demonstrator, C-FDHT, took place October 1, 2008, at Victoria Airport.[34][35] Two days later, the aircraft departed Victoria for a ferry flight to Orlando, Florida, site of the 2008 National Business Aviation Association (NBAA) Conference and exhibition. The first new build Series 400 Twin Otter (SN 845) made its first flight on February 16, 2010, in Calgary, Alberta.[36] Transport Canada presented Viking Air Limited with an amended DHC-6 Type Certificate including the Series 400 on July 21, 2010.[8] Six years after, in July 2016, 100 series 400 have been delivered to 34 customers operating in 29 countries.[37] In June 2017, 125 have been made since restarting production in 2010.[38]


Air Seychelles de Havilland Canada DHC-6-300 Twin Otter on Bird Island, Seychelles
A Seaborne Airlines DHC-6-300 fitted with floats makes a water landing at Saint Thomas, U.S. Virgin Islands
DHC-6 Series 100 
Twin-engine STOL utility transport aircraft, powered by two 550 shp (432 kW) Pratt & Whitney Canada PT6A20 turboprop engines.
DHC-6 Series 110 
Variant of the Series 100 built to conform to BCAR (British Civil Air Regulations).
DHC-6 Series 200 
Improved version.
DHC-6 Series 300 
Twin-engine STOL utility transport aircraft, powered by two 680 shp (715 ESHP) (462 kW) Pratt & Whitney Canada PT6A-27 turboprop engines.
DHC-6 Series 300M 
Multi-role military transport aircraft. Two of these were produced as "proof-of-concept" demonstrators. Both have since been reverted to Series 300 conformity.
DHC-6 Series 310 
Variant of the Series 300 built to conform to BCAR (British Civil Air Regulations).
DHC-6 Series 320 
Variant of the Series 300 built to conform to Australian Civil Air Regulations.
DHC-6 Series 300S 
Six demonstrator aircraft fitted with 11 seats, wing spoilers and an anti-skid braking system. All have since been reverted to Series 300 conformity.
Viking Air DHC-6 Series 400
Viking Air production, first delivered in July 2010, powered by two Pratt & Whitney Canada PT6A-34 engines, and available on standard landing gear, straight floats, amphibious floats, skis, wheel skis, or intermediate flotation landing gear.
Viking Air DHC-6 Series 400S Seaplane
Viking Air seventeen-seat seaplane version of the Series 400 with twin floats and corrosion-resistance measures for the airframe, engines and fuels system. Customer deliveries planned from early 2017.[39] 500 lb (230 kg) lighter than the 400.[40]
Twin-engine STOL utility transport, search and rescue aircraft for the Canadian Forces. Based on the Series 300 aircraft.
Twin-engine STOL utility transport aircraft for the U.S. Army Alaska National Guard. Six built. It has been replaced by the C-23 Sherpa in US Army service.
Parachute training aircraft for the United States Air Force Academy. The United States Air Force Academy's 98th Flying Training Squadron maintains three[41] UV-18s in its inventory as free-fall parachuting training aircraft,[42] and by the Academy Parachute Team, the Wings of Blue, for year-round parachuting operations. Based on the Series 300 aircraft.
United States Army designation for three Viking Air Series 400s delivered in 2013.[43]


281 Twin Otters were in airline service in 2016, and 26 on order : 112 in North/South America, 106 in Asia Pacific & Middle East (16 orders), 38 in Europe (10 orders) and 25 in Africa.[44] 530 were in service in June 2017.[38]

The Twin Otter has been popular not only with bush operators as a replacement for the single-engine de Havilland Canada DHC-3 Otter but also with other civil and military customers, with over 890 aircraft built. Many commuter airlines in the U.S. got their start by flying the Twin Otter in scheduled passenger operations.

Airlines with five aircraft or more[44]
Operator in service
[400 Viking]
Trans Maldivian Airways 49
Grand Canyon Airlines 15
Kenn Borek Air 11
Zimex Aviation 10 [1]
SonAir 8
Maldivian 7
Air Inuit 7
SVG Air 7
AeroGeo [6] (4)
Air Seychelles 2 [4]
Air Labrador 6
Aviastar Mandiri 6
MASwings [6]
Provincial Airlines 6
Seabird Airlines [6]
WinAir 5

Kaymac Inc., a government civilian contractor based in Nevada, operates 18.[45]

Accidents and incidents[edit]


Orthographically projected diagram of the de Havilland Canada DHC-6 Twin Otter.


DHC-6 Series 100 DHC-6 Series 300 DHC-6 Series 400
Flight deck crew 1–2
Seating 19 20 19
Length 51 ft 9 in (15.77 m)
Wingspan 65 ft 0 in (19.8 m)
Wing area 420 sq ft (39 m2)
Empty weight 5,850l lb
(2,653 kg)
7,415l lb
(3,363 kg)
6,881 lb
(3,121 kg)
Height 19 ft 4 in (5.9 m) 19 ft 6 in (5.94 m)
Maximum takeoff weight
11,566 lb
(5,246 kg)
12,500 lb
(5,670 kg)
Maximum landing weight 11,566 lb
(5,246 kg)
12,300 lb
(5,579 kg)
Maximum speed 160 knots (297 km/h at cruise altitude) 170 knots (314 km/h at cruise altitude)
Cruise speed 150 knots (278 km/h at cruise altitude)
Stall speed 58 knots (107 km/h at cruise altitude) (landing configuration)[not in citation given]
Range (Max fuel, no payload) 771 nmi (1,427 km) 775 nmi (1,434 km) 799 nmi (1480 km)
989 nmi (1832 km) with long range tankage
Maximum fuel capacity 382 US gal (1,447 L) 375 US gal (1421 L) 378 US gal (1466 L)
478 US gal (1811 L) with long range tankage
Service ceiling 25,000 ft (7,620 m)
Powerplants (×2) Pratt & Whitney PT6A-20
550 shp each
Pratt & Whitney PT6A-27
680 shp each
Pratt & Whitney PT6A-34
750 shp each
Rate of climb 1,600 ft/min (8.1 m/s)
Power/mass 0.12 hp/lb (0.20 kW/kg) or 8.33 lb/hp (5 kg/kW) reciprocal value

See also[edit]

Related development

Aircraft of comparable role, configuration and era


  1. ^ Reed Business Information Limited. "Viking restarts Twin Otter production". Retrieved 25 January 2015. 
  2. ^ Mike Ody, Erik Johannesson, Ian Macintosh and Neil Aird (October 2017). "Twin Otter Archive". 
  3. ^ "Airliner price index". Flight International. 10 August 1972. p. 183. 
  4. ^ Fred George (May 2017). "2017 Business Airplanes Purchase Planning Handbook" (PDF). Business & Commercial Aviation. Penton. p. 91. 
  5. ^ "Viking Acquires De Havilland Type Certificates." Archived 2006-08-24 at the Wayback Machine., February 24, 2006. Retrieved: May 15, 2010.
  6. ^ "Viking restarts Twin Otter production.", April 2, 2007. Retrieved: May 15, 2010.
  7. ^ Sarsfield, Kate. "Viking Twin Otter Series 400 certification approaches." Flightglobal', February 3, 2010. Retrieved: May 15, 2010.
  8. ^ a b "News releases." Archived 2010-09-08 at the Wayback Machine. Viking Air. Retrieved: May 15, 2010.
  9. ^ "Twin Otter – Zimex Aviation." Archived 2008-05-01 at the Wayback Machine. Retrieved: May 15, 2010.
  10. ^ Jang, Brent (2010-05-14). "The rebirth of a Canadian icon". The Globe and Mail. Retrieved 2012-08-08. 
  11. ^ "Viking Air Slashes Twin Otter Production, Lays Off 116". Aviation International News. Retrieved 3 July 2015. 
  12. ^ Phelps, Mark. "Updated Twin Otter Takes Off.", October 16, 2008. Retrieved: May 15, 2010.
  13. ^ "100th Viking Production Series 400 Twin Otter on Display at EAA Airventure 2017" (Press release). Viking Air. Jul 21, 2017. Archived from the original on 2017-07-28. 
  14. ^ North American Official Airline Guide (OAG), Feb. 1976 edition
  15. ^ "index". 2017-04-14. Retrieved 2017-04-26. 
  16. ^, airline system timetables
  17. ^, airline system timetables & OAG flight guides
  18. ^ "NSF PR 01-29 — Civilian Aircraft to Evacuate South Pole Patient." Retrieved: May 15, 2010.
  19. ^ "2001—Doctor Evacuated from the South Pole." Archived 2006-03-15 at Retrieved: May 15, 2010.
  20. ^ Williams, Jeff. "Pilot says pole flight wasn't his most challenging."
  21. ^ "Pilots return after historic South Pole rescue." Retrieved: May 15, 2010.
  22. ^ "Aircraft in Antarctica: British Antarctic Survey." Archived 2008-01-29 at the Wayback Machine. Retrieved: December 31, 2007.
  23. ^ "Calgary crew evacuates pair from South Pole in daring Antarctic rescue". CBC News. Retrieved 2016-06-23. 
  24. ^ "Official picture." Archived 2011-07-18 at the Wayback Machine. Retrieved: May 15, 2010.
  25. ^ Hulcazuk, Sergio. "Twin Otter: El castor patagonico." Archived 2010-08-13 at the Wayback Machine. Retrieved: May 15, 2010.
  26. ^ "Fleet." Kenn Borek Air. Retrieved: June 29, 2011.
  27. ^ a b "Twin Otter Series 400." Archived 2011-02-24 at the Wayback Machine. Viking. Retrieved: June 16, 2012.
  28. ^ a b "Twin Otter — Series 400". Viking Air. Archived from the original on 16 February 2015. Retrieved 14 February 2015. 
  29. ^ Bob Antol (April 2001). "The Rescue of Dr. Ron Shemenski from the South Pole". Bob Antol's Polar Journals. Retrieved 2013-01-23. 
  30. ^ "Doctor rescued from Antarctica safely in Chile". New Zealand Herald. 27 April 2001. Retrieved 2013-01-23. 
  31. ^ Transcript (26 April 2001). "Plane With Dr. Shemenski Arrives in Chile". CNN. Retrieved 23 January 2013. 
  32. ^ "Viking Twin Otter Series 400 Achieves Power On." Archived 2010-03-11 at the Wayback Machine., September 25, 2008. Retrieved: May 15, 2010.
  33. ^ "Twin Otter Shakes Its Wings Over Victoria Skies." Archived 2008-10-11 at the Wayback Machine., October 2, 2008. Retrieved: May 15, 2010.
  34. ^ "First Flight For New Twin Otter A "Boring" Success." Archived 2008-10-02 at the Wayback Machine., October 1, 2008. Retrieved: May 15, 2010.
  35. ^ Padfield, R. Randall and Matt Thurber. "Revived Twin Otter Makes First Flight." Archived 2008-10-11 at the Wayback Machine., October 8, 2008. Retrieved: May 15, 2010.
  36. ^ "Twin Otter Series 400 completes maiden sortie.", February 17, 2010. Retrieved: May 15, 2010.
  37. ^ "Viking Readies 100th Production Series 400 Twin Otter for Delivery" (Press release). Viking Air. Jul 12, 2016. 
  38. ^ a b Jon Hemmerdinger (June 21, 2017). "Viking targets China, Russia with Twin Otter". Flightglobal. 
  39. ^ "New Twin Otter Seaplane launched". Pilot. Archant Specialist. April 2016. p. 8. 
  40. ^ "A Visit with Viking". Air Insight. November 1, 2016. 
  41. ^ "94 FTS Fact Sheet." Archived March 3, 2016, at the Wayback Machine. Retrieved: August 12, 2009.
  42. ^ "UV-18." Retrieved: August 12, 2009.
  43. ^ Kris Osborn (1 October 2012). "Army developing new fixed-wing aircraft". Retrieved 25 January 2015. 
  44. ^ a b "World Airliner Census". Flight Global. 8 Aug 2016. 
  45. ^ Kaymac Inc. "About". 
  46. ^ National Transportation Safety Board "Aircraft Accident Report North Central Airlines, Inc., Allison Convair 340/440 (CV-580), N90858, and Air Wisconsin, Inc., DHC-6, N4043B, Near Appleton, Wisconsin, June 29, 1972, adopted April 25, 1973." National Transportation Safety Board Report Number NTSB-AAR-73-09. Retrieved: July 5, 2017
  47. ^ "A 36 años de un fatal accidente en los cerros tucumanos" (in Spanish). Retrieved 9 October 2017. 
  48. ^ "Deaths in the Family." Frontier Airlines Deaths. Retrieved: August 24, 2010.
  49. ^ "ASN Aircraft accident de Havilland Canada DHC-6 Twin Otter 200 CF-AIV Vancouver-Coal Harbour SPB, BC (CXH)". 1978-09-02. Retrieved 2017-04-26. 
  50. ^ "24 years after the accident." Prensa. Retrieved: March 5, 2005.
  51. ^ "National Transportation Safety Board Aircraft Accident Report NTSB-AAR-82-7" (PDF). National Transportation Safety Board. July 20, 1982. Retrieved July 5, 2017. 
  52. ^ "National Transportation Safety Board Aircraft Accident Report NTSB/AAR-90/05" (PDF). National Transportation Safety Board. September 25, 1990. Retrieved July 5, 2017. 
  53. ^ "National Transportation Safety Board Aviation Accident Final Report Accident Number: LAX92MA183". National Transportation Safety Board. August 5, 1993. Retrieved July 5, 2017. 
  54. ^ Ranter, Harro and Fabian I. Lujan. "ASN Aircraft accident de Havilland Canada DHC-6 Twin Otter 300 PK-NUK Molo Strait." Aviation Safety Network, 2011. Retrieved: June 27, 2011.
  55. ^ "Informe de accidente De Havilland DHC 300 – ACES HK2602" (PDF). Aeronautica civil de Colombia. Archived from the original (PDF) on 2014-01-02.  (in Spanish)
  56. ^ "Accident survenu le 24 mars 2001 sur l’île de Saint-Barthélemy (971) au DHC-6-300 « Twin-Otter » immatriculé F-OGES exploité par Caraïbes Air Transpor" (in French). Bureau d'Enquêtes et d'Analyses pour la Sécurité de l'Aviation Civile, October 7, 2001.
  57. ^ Clark, Amy S. "20 Thought Dead In Pacific Plane Crash." CBS News, August 9, 2007.
  58. ^ "Accident description: L'Armée de L'Air 742/CB." Aviation Safety Network. Retrieved: December 15, 2009.
  59. ^ "Crash." BBC News. Retrieved: October 8, 2008.
  60. ^ Hradecky, Simon. "Crash: Merpati DHC6 aircraft impacted mountain." Aviation Herald, October 16, 2009. Retrieved: May 15, 2010.
  61. ^ "Mixed weather reported before PNG plane crashed." The Australian, August 2, 2009. Retrieved: May 15, 2010.
  62. ^ , Shrestha, Manesh. "22 dead in Nepal plane crash." CNN, December 15, 2010. Retrieved: February 2, 2012.
  63. ^ "Honores de la FAE para seis víctimas de accidente" (in Portuguese)., January 20, 2011. Retrieved: February 2, 2012.
  64. ^ "18 survive crash-landing in Lawas". The Borneo Post. 25 August 2011. Retrieved 3 July 2017. 
  65. ^ "Yellowknife plane crash kills 2 people." CBC, September 22, 2011. Retrieved: February 2, 2012.
  66. ^ "23 jan 2013". Aviation Safety Network. 24 January 2013. Retrieved 25 January 2013. 
  67. ^ Radio-Canada (23 January 2013). "Un avion transportant trois Canadiens est disparu en Antarctique" (in French). Station Radio-Canada. Retrieved 23 January 2013. 
  68. ^ CTV News (23 January 2013). "Kenn Borek plane carrying three Canadians missing in Antarctica". CTV. Retrieved 23 January 2013. 
  69. ^ CTV News (26 January 2013). "Wreckage of missing plane found, crash deemed 'not survivable'". CTV News. Retrieved 26 January 2013. 
  70. ^ "Accident: Nepal DHC6 at Jomsom on May 16th 2013, runway excursion". AVHerald. 16 May 2013. Retrieved 16 May 2013. 
  71. ^ "Accident description". Aviation Safety Network. 
  72. ^ "Crash: Nepal DHC6 near Khidim on Feb 16th 2014, aircraft impacted terrain". Retrieved 2014-02-16. 
  73. ^ "Accident: Hevilift DHC6 near Port Moresby on Sep 20th 2014, impact with terrain". Retrieved 2014-09-22. 
  74. ^ "Sea plane with tourists crash-lands, all passengers safe | Minivan News". 2015-07-02. Archived from the original on 2015-07-22. Retrieved 2017-04-26. 
  75. ^ Sugam Pokharel, Holly Yan and Greg Botelho, CNN (24 February 2016). "Nepal plane crash: Tara Air plane goes down, 23 feared dead". CNN. 
  • Hotson, Fred W. The de Havilland Canada Story. Toronto: CANAV Books, 1983. ISBN 0-07-549483-3.
  • Rossiter, Sean. Otter & Twin Otter: The Universal Airplanes. Vancouver: Douglas & McIntyre, 1998. ISBN 1-55054-637-6.

External links[edit]