The Avro Lancaster is a British four-engined Second World War heavy bomber designed and built by Avro for the Royal Air Force (RAF). It first saw active service with RAF Bomber Command in 1942 .
The "Lanc", as it was affectionately known, thus became the most famous and most successful of the Second World War night bombers, delivering 608,612 long tons of bombs in 156,000 sortie.