The Avro Lancaster is a British, four-engine, medium-wing metal structure strategic bomber from the Second World War. The prototype flight took place in January 1941 and mass production started in the same year. The basis for the creation of the Lancaster was the Avro Manchester plane. As a drive served min. four Rolls-Royce Merlin XX V-engines with a power of 1280 HP each (Mk.I) or Bristol Hercules VI engines with a power of 1737 HP each, although other engines were also used. Serial production took place at the Avro, Metropolitan-Vickers, Armstrong Whitworth, Vickers Armstrong and Victoria Aircraft plants and by the beginning of 1946, 7377 aircraft were produced. There were four main versions of the Avro Lancaster (Mk.I, Mk.II, Mk.III and Mk.X) that were externally similar to each other. The Avro Lancaster was the RAF's primary strategic bomber, and at the same time earned a reputation for being the best. It was easy to pilot, had high lifting capacity and was characterized by a long durability of the structure. It happened that the bomber was able to complete the mission and return to base, even despite the failure of one engine. The planes entered service in December 1941 and served at the end of the war, primarily performing strategic bombing tasks. It was the Lancasters of the RAF 617 Bomber Squadron that were used in May 1943 to damage the Ruhr water dams. Technical data (Mk.I version): length: 21.11m, wingspan: 31.09m, height: 6.25m, maximum speed: 456km / h, maximum range: 4073km, maximum ceiling 6500m, armament: fixed - 8 rifles 7.7mm Browning machine guns, mounted - up to 6300 kg of bombs or one Grand Slam bomb (10000 kg) after modifying the bomb chamber.