The Boulton & Paul ‘Overstrand’
The Boulton & Paul ‘Overstrand’, built at their factory in Norwich, was the last of the twin-engine biplane medium bombers of the Royal Air Force, a series that had begun during the First World War with the likes of the Vickers Vimy and Handley Page Type O. The ‘Overstrand’ only saw brief service in the late 1930s and by the outbreak of the Second World War only a few surviving aircraft remained in operation with training units.
The Overstrand was essentially an upgrade of Boulton & Paul’s ‘Sidestrand’ which had first flown in 1928 named after the village just a short walk from Overstrand. The ‘Sidestrand’ was similar to its First World War predecessors in that it had open cockpits and hand-operated defensive machine guns.
However, unlike its predecessors, the ‘Sidestrand’ could fly at 140 mph (225 km/h) making operating the exposed gun positions difficult, particularly in the aircraft’s nose. To overcome this problem, the ‘Overstrand’ was fitted with an enclosed and powered nose turret mounting a single Lewis gun. As such the ‘Overstrand’ was the first RAF aircraft to have a power-operated turret.
Rotation was handled by pneumatic motors while elevation and depression of the gun used hydraulic rams. The pilot’s cockpit was also enclosed but the dorsal and ventral gun positions remained open, though shielded. The first ‘Overstrand’, at the time designated the ‘Sidestrand Mk IV’, flew in 1933, powered by two 580 hp (430 KW) Bristol
Pegasus IM.3 engines, instead of the ‘Sidestrand’s’ 460 hp (340 kW) Bristol Jupiters, and was capable of 153 mph. Twenty Four ‘Overstrands’ were produced and in 1936 began replacing the ‘Sidestrand’ in service. The ‘Overstrand’ was operated by No.101 Squadron RAF which had been the sole ‘Sidestrand’ squadron and briefly by No. 144 Squadron RAF though they were replaced by Bristol Blenheims in 1938.
At the outbreak of the Second World War, eleven ‘Overstrands’ remained in service and six of these were used for gunnery training. They remained in operation until May 1941.