Scottish Aviation had taken over production of the original Jetstream design from Handley Page and when it was nationalised along with other British companies into British Aerospace (now BAE Systems) in 1978, BAe decided the design was worth further development, and started work on a "Mark 3" Jetstream. As with the earlier 3M version for the USAF, the new version was re-engined with newer Garrett turboprops (now Honeywell TPE331) which offered more power (flat rated to 1,020 shp/760 kW with a thermodynamic limit of 1,100 shp/820 kW) and longer overhaul intervals over the original Turbomeca Astazou engines. This allowed the aircraft to be offered in an 18-seat option (six rows, 2+1), with an offset aisle, and with a water methanol option for the engine to allow the ability to operate at maximum load from a greater range of airfields, particularly in the continental United States and Australia. The result was the Jetstream 31, which first flew on 28 March 1980, being certificated in the UK on 29 June 1982. The new version proved to be as popular as Handley Page hoped the original model would be, and several hundred 31s were built during the 1980s. In 1985, a further engine upgrade was planned, which flew in 1988 as the Jetstream Super 31, also known as the Jetstream 32. Production continued until 1993, by which time 386 31/32s had been produced. Four Jetstream 31s were ordered for the Royal Navy in 1985 as radar observer trainers, the Jetstream T.3, but were later used for VIP transport. In 1993, British Aerospace adopted the Jetstream name as its brand name for all twin turboprop aircraft. As well as the Jetstream 31 and Jetstream 32, it also built the related Jetstream 41. For more details including variants, click here.