The Twin Otter is still Canada's most successful commercial aircraft program with more than 800 built and it remained popular for its rugged construction and useful STOL performance.

Development of the Twin Otter began in January 1964 when De Havilland Canada started design work on a new STOL twin turboprop commuter airliner and utility transport. The first Twin Otter entered service with long time supporter of De Havilland Canada, the Ontario Department of Lands in Canada. Production of Twin Otter was completed in 1988, comprising of 115 Series 100s, Series 200s and 614 Series 300s