AVRO LANCASTER, the most successful British heavy bomber of World War II. The Lancaster emerged from the response by A.V. Roe & Company, Ltd.,
to a 1936 Royal Air Force specification calling for a bomber powered by two 24-cylinder Rolls-Royce Vulture engines. The resultant aircraft, the Manchester, first flew in July 1939, entered production the following year, and was committed to combat in February 1941.
However, the Vulture engine proved to be a failure, and the Manchester was produced only in small numbers.
Avro then proposed a redesigned Manchester powered by four Rolls-Royce Merlin engines, and the result was the Lancaster.
