A special cell in the fuselage could accommodate a single torpedo, a single 500lb bomb, or two 250lb bombs; additional bombs could be carried on external bomb racks on the mainplane. Other armaments included the pilot's forward-firing .303-inch Vickers machine gun and the twin Lewis guns installed in the turret. Comprehensive marine gear, including a collapsible dinghy, was also provided.
The undercarriage consisted of two oleo-pneumatic legs that retracted rearwards into the nacelles, which were fitted with spring-loaded doors; hand-operated hydraulic brakes were fitted. As built, the Botha I was powered by a pair of Bristol Perseus X radial engines, each driving a de Havilland Type 5/11 Hydromatic three-bladed constant-speed propeller. The engines, mounted on the central section of the wing in wide-chord cowlings, were fitted with controllable cooling grills.