[5] A long forecastle was planned, reaching back beyond the aft funnel,[8] although in 1946, it was suggested to change to a flush-deck hull.

[5] The machinery was to be laid out in a unit scheme, with two sets of boilers and turbines separated to reduce the potential for a single torpedo or shell hit to cause complete loss of power.

It was noted though by the Director of Naval Construction in June 1945 that the boiler rooms were still too close to avoid the possibility of both being knocked out by a single hit.

[14] Secondary armament consisted of six QF 4.5 inch (113 mm) Mark V dual purpose guns in twin turrets as used in the Daring-class destroyer.

[15] The guns were semi-automatic and fitted with a power loader, giving a maximum rate of fire of 24 rounds per minute per barrel.

When the gun entered service, the power rammer proved unreliable and hand loading reduced the rate of fire to about 10–12 rounds per minute per barrel.

[7][3][17] The programme continued following the end of the war, with pressure growing to divert shipbuilding capacity to build more profitable ocean passenger liners, with it being hoped in November 1945 that two ships could be laid down as soon as possible.

The order for Bellerophon was cancelled with the shipbuilder on 28 February 1946 and the Neptune class as whole stopped (in ADM 205/64) due to the lack of finance for cruiser construction in post war austerity Britain[21] and deep division among the naval staff over the role of the cruiser in AA defence and joint operation with aircraft carriers in defence of and attack on trade.

Given the priority of air defence, further consideration and planning with the United States Navy was required to determine the desired size and calibre of long range AA guns, and particular study was ordered on the new US Worcester, Mitscher and Juneau classes.

[23] The new 6- and some 3-inch mounts were eventually used when three Tiger-class cruisers were completed to a new design in the late 1950s,[24] The County-class destroyers met the Royal Navy's requirements for a surface-to-air missile armed ship.