BAe Jetstream Jetstream 31

When Scottish Aviation was absorbed into British Aerospace in 1978, the new company looked again at the old Jetstream and decided the design deserved another chance. The problem was the same one as in 1967: the engine. The answer was the one already tried for the US Air Force a decade earlier — Garrett TPE331 turboprops, now Honeywell, flat rated to 1,020 shaft horsepower with a thermodynamic limit of 1,100 and far longer overhaul intervals than the Astazou.

That power margin moved the aircraft into a different class. It allowed an eighteen-seat cabin in six rows of 2+1 with an offset aisle, and a water-methanol option that let the aeroplane leave demanding airfields at maximum weight — a decisive argument in the continental United States and in Australia.

The Jetstream 31 flew on 28 March 1980 and was certificated in Britain on 29 June 1982. Unlike the original, it sold: several hundred left the factory during the 1980s, and the aircraft became a fixture of American feeder networks, European regional operators and, later, Latin American and African carriers. In July 2019 seventy Jetstream 31s were still in airline service, half of them in the Americas.

It is by far the variant the type is identified with, and its figures are the ones this encyclopedia uses for the model as a whole. It is also the basis of every later sub-version — Corporate, EP, EZ, Special, Executive Shuttle, QC — and of the Super 31 itself.