original /23 design was ready for flight by late 1943. This gave the team some breathing room, so they redesigned the /26's inlets for increased air flow, and thus thrust. Adding improved fuel and oil systems, the newly named Derwent Mk.I entered production with 2,000 lbf (8.9 kN) of thrust. Mk.II, III and IV's followed, peaking at 2,400 lbf (10.7 kN) of thrust. The Derwent was the primary engine of all the early Meteors with the exception of the small number of Welland-equipped models which were quickly removed from service. The Mk.II was also modified with a cropped impeller (turbine unchanged) and a reduction gearbox driving a five-bladed propeller. It was called the Rolls-Royce RB.50 Trent and was the first turboprop to fly. Two were installed in a Meteor I. Mk.V The basic Derwent design was also used to produce a larger 5,000 lbf (22.2 kN) thrust engine known as the Rolls-Royce Nene. The Nene was such an advance over the Derwent that Derwent development effectively ended. The Nene was, however, larger in diameter and so could not fit into the nacelles of the Meteor. The next Derwent version, the Derwent Mk.V, was instead produced by scaling down the new Nene to the diameter of the previous Derwent, specifically for use on the Meteor. Several Derwents and Nenes were sold to the Soviet Union by the then Labour government, causing a major political row, as the Nene was the most powerful production turbojet in the world at the time. The Soviets promptly reverse engineered the Derwent V and produced their own unlicensed version, the Klimov RD-500. The Nene was reverse-engineered to form the propulsion unit for the famous MiG-15 jet fighter. The Derwent Mk.V was also used on the Canadian Avro Jetliner, but this was not put into production. On 7 November 1945, a Meteor powered by the Derwent V set a world air speed record of 606 mph (975 km/h) TAS. Other applications An unusual application of the Derwent V was to propel the former paddle steamer . The 1888 ship had her steam machinery removed and replaced by four Derwents in 1950–1951. The purpose of this was to conduct research on the friction and drag produced by a ship hull in real-life conditions. Jets were preferable to marine propellers or paddles as these would have created a disturbance in the water, and the force exerted by them was