The only aircraft type designed for the Vulture to actually go into production was the twin-engined Avro Manchester. When the engine reliability problems became clear, the Avro team persuaded the Air Ministry that switching to a four-Merlin version of the Manchester, which had been in development as a contingency plan, was preferable to retooling Avro's factories to make the Handley Page Halifax. The resulting aircraft was initially called the Manchester Mark III and then renamed Avro Lancaster, going on to great success as the RAF's leading heavy bomber.