The Bristol Blenheim was a twin-engine high performance all-metal medium bomber aircraft, powered by a pair of Bristol Mercury VIII air-cooled radial engines, each capable of . Each engine drove a three-bladed controllable-pitch propeller, and were equipped with both hand-based and electric engine starters. To ease maintenance, the engine mountings were designed with a split-segment to facilitate rapid engine removal without disturbing the carburettors. A pair of fuel tanks, each containing up to 140 gallons, were housed within the center-section of the fuselage.