Before the issue of Air Ministry Specification 12/41, it had been standard RAF practice to use out dated aircraft, however unsuitable, for the task of target towing. The outbreak of World War 2 had high lighted this short-sighted policy, leading to the procurement of an aircraft designed specifically for such a role. The Miles M.25 prototype (LR241) was built in a very short space of time and flown for the first time on 24th April 1942, the aircraft being based on the Miles Master Mk II but apart from an outward family likeness, however, the Martinet and Master detail design and construction had little in common. Some changes included the nose being lengthened to compensate for the weight of target-towing equipment, and special attention was given to the engine cooling arrangements, owing to the severe conditions imposed by towing. Incorporated within a modified cockpit was the drogue cable winch, which could be powered by an electric motor or wind-driven propeller, and there was comfortable space for the operator and stowage of the drogue targets. The type entered service as the Miles Martinet and between 1942 and 1945 a total of 1,724 was built; the type was complemented in 1946 by the M.50 Queen Martinet which had been developed to Specification Q.10/43. This was a radio-controlled pilotless target version of the Martinet, 11 being built as new and the remaining 54 being conversions of M.25s. Planned variants included a glider-tug version of the Martinet, similar to the Master GT Mk II, and the M.37 two-seat trainer of which two prototypes were built. Six surplus Martinets received civil registrations after the war, four of them sold to Sweden and operated by the civil target-towing company Svensk Flygjärst.