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B III Special
Variant built to take the "Upkeep" (bouncing) bomb for the dam busting raids. The struts and mechanism to take the cylindrical bomb were fitted below the bomb bay, and search-lights fitted for the simple height measurement system which enabled the accurate control of low-flying altitude at night. The mid-upper turret was removed to save weight – the gunner was moved to the front turret to allow the bomb aimer to assist with map reading.