Bristol Bolingbroke - Variants

Variants

Bolingbroke Mk I

Twin-engine maritime patrol bomber aircraft, powered by two Bristol Mercury VIII radial piston engines, with British equipment. 18 built.

Bolingbroke Mk II

Conversion of fifth Mk I with US equipment - prototype of Mk IV.

Bolingbroke Mk III

Floatplane conversion of sixteenth Bolingbroke Mk I, with two Edo floats.

Bolingbroke Mk IV

Twin-engine maritime patrol bomber aircraft, equipped with anti-icing boots and a dinghy, also fitted with American and Canadian instruments and equipment, powered by two Bristol Mercury XV radial piston engines, 134 built.

Bolingbroke Mk IVW

Sub-version of Mk IV powered by two 825 hp (615 kW) Pratt & Whitney SB4G Twin Wasp Junior radial piston engines as contingency against possible shortages of Mercury engines. The Mk IVW's performance was below that of the Mk IV and the supply of the British engines was maintained so production returned to the Mk IV after only 15 aircraft were built.

Bolingbroke Mk IVC

Version of Mk IV with 900 hp (671 kW) Wright R-1820 Cyclone engines not requiring high octane fuel. One built.

Bolingbroke Mk IVT

Multi-purpose trainer aircraft. A total of 350 built powered by Mercury XV engines, followed by a further 107 powered by the low-octane fuel Mercury XX* engine, giving a total of 457 built, with a further 51 cancelled. 6 Mk IVT were converted to dual controls. A further 89 were converted to Mk IVTT Target Tug with the addition of winching gear in the rear cabin and target drogue storage in the bomb bay.