de Havilland DH.72
The de Havilland DH.72 was a large British three-engined biplane bomber, designed as a Vickers Virginia replacement.Air Ministry specification B.22/27 was for a Vickers Virginia night bomber replacement and de Havilland obtained an order for a single prototype.It took a long time to build – about three years – partly because the contract called for duralumin clad wings and de Havilland were not familiar with metal construction methods, and partly because the Air Ministry required a nose gunner's position, which required the central engine of the Hercules to be moved to the upper wing.The fuselage was flat-sided, with a door just aft of the wings and an internal cabin with a pair of windows just forward of the propellers.[1] The DH.72 first flew on 27 July 1931,[3] and visited RAE Farnborough in mid-November before going on to competitive trials at RAF Martlesham Heath.