Every successful outsize vehicle constructed by man has been the final version of a series of progressive experiments in ascending size. The evolution of the giant steamship "Queen Mary" from the primitive coracle may be instanced, but in our own sphere the big four-engined Short Empire flying boats provide a more graphic illustration. These monoplanes were the result of scale experiments, first with the twin engined Short Scion monoplane and then with the four engined Short Scion Senior, the information gathered from operation of these two types having a direct influence on the design of the flying boats.
Such careful steps are expensive both in time and money, but the final result is well worth the effort, as was appreciated by the Miles organisation when they decided, in 1939, to build the "X" Minor, a small experimental monoplane based on the design of the eight engined Miles "X" Transport machine.
As in the "X", the "X" Minor had an aerofoil section and wings with thickened roots blending into the fuselage, but the main difficulty was encountered with the motors, which could not be accommodated entirely within the wings.
Due to the fact that it was impossible in this size to make an exact scale model, the information gained was confirmatory of the wind tunnel results rather than actually quantitative data. It was hoped that at a later date it may be possible to build a larger and more exact scale model with horizontally opposed engines buried in the wing.