 Although these launches were inclined and the rockets didn't achieve the altitude necessary to be regarded as sub-orbital spaceflight, the Backfire report remains the most extensive technical documentation of the rocket, including all support procedures, tailored vehicles and fuel composition.Subsequently, the British Interplanetary Society proposed an enlarged man-carrying version of the V-2 called "Megaroc".The plan, written in 1946, envisaged a three-year development programme culminating in the launch of test pilot Eric Brown on a sub-orbital mission in 1949.