Britten-Norman Islander BN-2T Turbine Islander

The idea of putting turbines in the Islander is as old as Fairey's ownership of Britten-Norman, but the route was long. The first attempt, the Turbo Islander with Lycoming LTP101 engines, proved to have too much power for the airframe: the aircraft could not use it and the project had to be redesigned. The answer came with the Allison 250-B17C, better sized for a machine whose virtue was never speed, and the result entered service in 1981 as the BN-2T.

The BN-2T keeps the nine-passenger capacity and the operational habits of the piston Islander, but it changes the mission profile entirely. Less vibration, simpler starting, jet fuel instead of petrol — a decisive difference where avgas is expensive or simply unavailable — and power margin to carry aerials, turrets and heavy equipment under the wing and in the nose. That electrical and aerodynamic carrying capacity explains its later career.

From the BN-2T came the British Army's Islander AL1, used for aerial reconnaissance and photography in Northern Ireland and redesignated Islander R1 in 2019 on transfer to the Royal Air Force; the RAF's own three Islander CC2 and CC2A, retired in 2017; and the successive generations of turboprop Defender flown by gendarmeries, coastguards and navies in half a dozen countries. It is, in practice, the Islander that still turns up in military inventories.