Shorts' SC. I, of which two were built in the 1955 to 1956 period, developed to study the low speed end of a British research programme into VTOL. The basic propulsive layout adopted by Shorts can be seen in the ground view of the ill-fated second machine, XG 905. It consisted of a single, rear-mounted 2,130lb s.t. Rolls-Royce RB 108 for forward flight and four more RB 108s mounted vertically in the central fuselage to provide vertical lift. As was fast becoming the practice, puffer jets were used for attitude control while operating at low speed or in the hover. First flown conventionally on 2 April 1957, XG 905 hovered for the first time just over a year later, on 28 May 1958, which in turn led to the first full transitional flight on 6 April 1960. Sadly, XG 905 was to crash on 2 October 1963, fatally injuring its RAE test pilot. J. R. Green.