The astounding progress of aeronautical research and design is aptly illustrated by the fact that the Yeovil day-bomber biplane, the design of which was commenced by Westland in 1923, weighed 3400kg when completely loaded and bombed-up - twenty years later it was possible for the Royal Air Force to drop a single bomb of more than one and a half times this weight, from an aeroplane weighing 28600kg in its fully laden state!
The Yeovil was the first of the Westland post-war military designs, to an Air Ministry Specification, and was built specially to accommodate the biggest engine then available, the newly developed 650hp Rolls Royce Condor engine. Three machines in all were produced, numbered J.7508, J.7509 and J.7510, the first slightly differing from the others in undercarriage arrangement and the fairing of the wing tanks. The prototype was initially test-flown at Andover, in the summer of 1925, by Captain Frank Courtney, the development testing of the subsequent machines being in the hands of Major L. P. Openshaw.
Several other firms built prototypes to the same Specification and, although the Yeovil did not go into production - the Hawker Horsley biplane eventually proving the winner of the competition and securing the production contract - the three examples built were used for valuable research work, before their flying careers ended.
A.H.Lukins "The Book of Westland Aircraft", 1943
