The Handley PageHP 57 Halifax was a British four engined heavy bomber of the Second World War. The prototype Halifax flew in October 1939 and was fitted with four Rolls-Royce Merlin X engines and had a maximum speed of 448 kmh. The first production Halifax, the mark I flew in October 1940, and the Halifax went into service in March 1941. The original Halifax were armed with eight 0.303 inch machine-guns, two in a Boulton Paul nose turret, four in a Boulton Paul tail turret and two hand-operated beam-guns. Later a Boulton Paul Hudson-type two-gun turret was introduced in the mid-upper position in place of the two beam-guns. The production Halifax had a maximum speed of 432 kmh and a range of 4800 km. A crew of seven was normally carried comprising of two pilots, navigator, radio operator and three gunners. A bomb load of 6580 kg could be carried. Research Halifax