Originally Posted by
DANbudgieman
The forward turret was indeed rarely used, however removal of the forward (and mid upper) was primarily driven by weight considerations.
The main aim was to reduce airframe weight in order to allow the carriage of outsize weapons such as the 22,000lbs "Grand Slam."
These specialised weapons were expected to be delivered in daylight when flak was the primary threat. The ability to deliver theses weapons from a higher altitude in order to avoid the worst of the flak may also have been a consideration.
By the latter days of the war a strong escort force would be deployed in order to provide an effective screen against a much depleted Luftwaffe, hence the turrets were largely superfluous.
You forget that Bomber Command still operated by night until near the end of the war and suffered worse percentage losses at night than by day. Whilst the Luftwaffe at night was deprived of many of it's advantages, early warning for one, it still posed a threat. The turrets were largely superfluous anyway throughout the war, but the main reason they were not removed ( unless done so for the dropping of certain weapons) was morale. The dropping of Grand Slams in particular was done way below the operating height of a normal Lancaster ( and below the height calculated by Wallis for maximum effect).They just couldn't get to height with the weight carried, removing the turrets were a weight saving measure but they were still very vulnerable to flak, as they operated well within the 88s range. Only Mosquitoes could outfly the 88s.