The Lancasters shown in the clip are the BII, with the Bristol Hercules radial engine. 300 BIIs were built by Armstrong Whitworth and were used mostly by Canadian squadrons in 6 Group.
The aircraft’s Squadron can be indentified by their call sign letters. 426 Squadron’s letters were “OW” which can be seen on some of the aircraft in the film. You will also see “EQ” on the aircraft at the beginning of the film which belonged to RCAF 408 Squadron. No. 408 converted to Lancasters in August 1943 after joining 426 Squadron at RAF Linton-on-Ouse.
Probably the most famous allied bomber of World War Two was the Avro Lancaster of Bomber Command. It was born out of the failure of the twin engine Manchester bomber. Avro took the basically sound Manchester airframe and redesigned it to take four Rolls Royce Merlin engines.
Like so many good planes the essence of the Lancaster's success was its simplicity and robust structure. It was also remarkably adaptable as evidenced by its many roles such as the famous Dambuster raid through to the carrying of the 11 ton Grand Slam bomb.
Another highlight of the Lancaster's career was the sinking of the German battleship TIRPITZ on November 12, 1944 in a Norwegian Fjord. For the attack on the TIRPITZ, 31 aircraft from number 617 and number 9 Squadrons took part in the raid. Each aircraft carried a 12,000 pound Tallboy bomb.
Even though the Lancaster proved to be one of the most successful bombers of the war, this success did not guarantee immunity from losses. Of the over 7,300 Lancasters built during the war more than 3,600 were lost on operations. Number 419 Squadron alone lost 129 aircraft, more than fives its normal squadron strength. But more disturbing was the tremendous loss of life, especially in Bomber Command. Of the over 17,000 RCAF casualties during the war, close to 10,000 of the deaths were sustained in squadrons assigned to Bomber Command. Overall, more than 60% of the bomber flight crews did not survive the war.