In the autumn of 1941, de Havilland found that it had the spare design capacity to work on a new project. At this point, the Mosquito had entered full-rate production and preliminary work on a jet-propelled fighter aircraft, which became the Vampire, was waiting for the production of prototype engines. The company promptly recognised a need for a high-speed, unarmed, night bomber powered by a pair of large Napier Sabre piston engines and a design for such an aircraft was first proposed under the designation "D.H. 101" in October 1941. A design team led by R. E. Bishop with C. T. Wilkins assisting, was assembled with the aim of developing the D.H. 101, which was initially pursued as a private venture.