The BAE Jetstream 31 is a small twin turboprop airliner, with a pressurised fuselage, originally designed to meet the requirements of the United States feederliner and regional airline market. Scottish Aviation formed the company Jetstream Aircraft to produce the aircraft. After Scottish Aviation went bankrupt and was merged into British Aerospace in 1978, BAe decided the design was worth further development, and started work on a “Mark 3” Jetstream. The result was the Jetstream 31, which first flew on March 28, 1980. The new version proved to be popular and several hundred 31s were built during the 1980s. In August 2006 a total of 158 BAe Jetstream 31 and 32 aircraft remain in airline service.

The BAe Jetstream 31 has a crew of two and has a seating capacity of 19 passengers. It has a maximum speed of 488 km/h and a range of 1,260 km. It incorporates two Garrett TPE331-10UG turboprop with 701 kW each. The BAe Jetstream 31's major operators include Coast Air, Direktflyg, Sun Air of Scandinavia, Blue Islands, Boston-Maine Airways and RegionsAir and Air National of New Zealand. Other airlines also operate the BAe Jetstream.