Handley Page Halifax

The Handley Page Halifax is a British Royal Air Force (RAF) four-engined heavy bomber of the Second World War. It was developed by Handley Page to the same specification as the contemporary twin-engine Avro Manchester.

The Halifax has its origins in the twin-engine H.P.56 proposal of the late 1930s, produced in response to the British Air Ministry's Specification P.13/36 for a capable medium bomber for "world-wide use." The H.P.56 was ordered as a backup to the Avro 679, both aircraft being designed to use the Rolls-Royce Vulture engine. The Handley Page design was altered to use four Rolls-Royce Merlin engines while the rival Avro 679 was produced as the twin-engine Avro Manchester which, while regarded as unsuccessful mainly due to the Vulture engine, was a direct predecessor of the Avro Lancaster. Both the Lancaster and the Halifax emerged as capable four-engine strategic bombers, thousands of which were used during the War.