In the search for alternative uses for the Defiant, which included limited service with the RAF Search and Rescue Force and suitability trials for cooperative operations with the British Army, it was determined that Defiant production would continue in order to satisfy a pressing requirement for high speed gunnery targets. A dedicated version of the aircraft, the "Defiant TT Mk I", was developed for this purpose; modifications included the removal of the turret, the installation of target-towing equipment, including a target stowage box and a wind-driven winch, and the addition of a winch operator under an enclosed canopy. In January 1942, the prototype Defiant TT Mk I, "DR863", conducted its maiden flight; fighter production was phased out shortly thereafter.