Boulton Paul Overstrand

Boulton Paul Overstrand Biplane gun turret
Hughes relatively easily converted the open cockpit to an enclosed glazed one, but the exposed forward gun position was not so easy. Hughes' solution was to be a first for the RAF, he built in a fully enclosed powered gun turret. The turret utilised pneumatic turbine motors to rotate the turret, and twin hydraulic rams to depress and elevate the single fitted .303 Lewis machine gun. As the two dorsal and single ventral gun positions were better protected from the slipstream, they were left open. This completed the design of the Boulton Paul Overstrand.

Boulton Paul Overstrand Bomber production
The Boulton Paul Overstrand first flew in 1933 and, as there had already been three previous redesigns, it entered service with the RAF in 1934 as the Boulton Paul Sidestrand Mk IV. A total of twenty eight Boulton Paul Overstrand aircraft were produced, four of which were converted from surplus Boulton Paul Sidestrand airframes.

Boulton Paul Overstrand Biplane in RAF service.
The Boulton Paul Overstrand entered service with No. 101 and 144 Squadrons, serving in the role of a bomber for four years before being replaced by the RAF's new Bristol Blenheim monoplane bombers.

Boulton Paul Overstrand Bomber during WW2
When WW2 broke out in 1939, only eleven of the RAF's Boulton Paul Overstrand aircraft remained operational, and these had already been de-rated to Air Observer & Bombing and Gunnery School duties. A few others were used as test-beds for the Balloon Development Unit & Army Co-operation Development Units. The Boulton Paul P.75 Overstrand was finally retired in May 1941, by which time only a handful of aircraft remained airworthy.

Various scale models, model kits and plans of this aircraft have been available in the market place.

Boulton Paul Sidestrand Mk IV Biplane Specifications:

Boulton Paul Overstrand Crew: Pilot and two or three gunners
Boulton Paul Overstrand Length: 46 ft 0 in (14.02 m)
Boulton Paul Overstrand Wingspan: 72 ft 0 in (21.95 m)
Boulton Paul Overstrand Height: 15 ft 6 in (4.73 m)
Boulton Paul Overstrand Wing area: 980 ft² (91.1 m²)
Boulton Paul Overstrand Empty weight: 7,936 lb (3,607 kg)
Boulton Paul Overstrand Maximum takeoff weight: 11,923 lb (5,420 kg)
Boulton Paul Overstrand Engines: Twin 580 hp (433 kW) Bristol Pegasus II.M3 9 cylinder radial engines
Boulton Paul Overstrand Maximum speed: 148 mph (129 knots, 238 km/h)
Boulton Paul Overstrand Range: 545 mi (474 nmi, 872 km)
Boulton Paul Overstrand Service ceiling: 21,300 ft (6,490 m)

Boulton Paul Sidestrand Mk IV Biplane Armament:

Guns:
Three .303 in (7.7 mm) Lewis machine guns, one each in the nose turret, dorsal and ventral positions

Bombs:
1,500 lb (680 kg) bombs (2 × 500 lb/227 kg and 2 × 250 lb/113 kg) and 4 × 20 lb (9 kg) bombs could be carried on fuselage racks.