The decision was made to introduce a series of other minor improvements to produce the "Whitley Mk V". These included the modification of the tail fins and rudders, the fitting of leading edge de-icers, further fuel capacity increases, a smaller D/F loop in a streamlined fairing being adopted, and the extension of the rear fuselage by 15 in (381 mm) to improve the rear-gunner's field of fire. The Whitley Mk V was by far the most numerous version of the aircraft, with 1,466 built until production ended in June 1943.