Editing Avro Lancaster (section)

===Further development===
[[File:Avro Lancaster B I PA474.jpg|thumb|left|PA474, Lancaster B.I of the RAF Battle of Britain Memorial Flight]]
The Lancaster B.I was never fully superseded in production by a successor model, remaining in production until February 1946.<ref name="goul garb 4"/> According to aviation authors Brian Goulding and M. Garbett, the Lancaster B.I altered little during its production life, partially as a result of the sound basic structure and design; of the visible changes, the fuselage side windows were deleted, the [[Perspex]] chin of the bomb-aimer was enlarged, and a larger [[Astrodome (aeronautics)|astrodome]] was provided.<ref name="goul garb 4 5"/> Various additional bumps and [[blister]]s were also added, which typically housed [[radar]] equipment and [[radio]] navigational aids. Some Lancaster B.I bombers were outfitted with bulged bomb bay doors in order to accommodate increased armament payloads.<ref name="goul garb 4 5">Goulding and Garbett 1966, pp. 4–5.</ref>

Early production Lancaster B.Is were outfitted with a ventral gun turret position.<ref name="goul garb 5"/> In response to feedback on the lack of application for the ventral turret, the ventral turret was often eliminated during the course of each aircraft's career. While some groups chose to discard the position entirely, various trials and experiments were performed at [[Duxford Aerodrome|RAF Duxford]], [[Cambridgeshire]] and by individual squadrons.<ref name="goul garb 5"/> A total of 50 Austin-built Lancaster B.Is was constructed to a non-standard configuration, having a Frazer Nash turret installed directly above the bomb bay; however, this modification was largely unpopular due to its obstruction of the internal walkway, hindering crew movements. Various other turret configurations were adopted by individual squadrons, which included the removal of various combinations of turrets.<ref name="goul garb 5 6">Goulding and Garbett 1966, pp. 5–6.</ref>

The ''Lancaster B.III'' was powered by [[Packard V-1650|Packard Merlin]] engines, which had been built overseas in the [[United States]], but was otherwise identical to contemporary B.Is.<ref name="goul garb 4"/> In total, 3,030 B.IIIs were constructed, almost all of them at Avro's [[Newton Heath]] factory. The Lancaster B.I and B.III were manufactured concurrently and minor modifications were made to both marks as further batches were ordered. The B.I and B.III designations were effectively interchangeable simply by changing the engines used, which was occasionally done in practice.<ref name="goul garb 4"/> Examples of modifications made include the relocation of the [[Pitot tube|pitot head]] from the nose to the side of the cockpit and the change from de Havilland "needle blade" propellers to [[Hamilton Standard]] or [[Nash-Kelvinator Corporation|Nash Kelvinator]] made "paddle blade" propellers.<ref>"The Design and Development of the Avro Lancaster". ''Manchester Branch of the Royal Aeronautical Society''.</ref>