Early SCB-27A schemes and SCB-27B

[A Tentative Fleet Plan]

Thus is with reference to Norman Friedman's US Aircraft Carriers and his article in Warship No.18.

Initially BuShips considered two designs:

Scheme A -a carrier with an island capable of operating aircraft with an AUW of 45,000lbs with enlarged after and deck-edge elevators able to strike down a fully-armed bomber.

Scheme B -a flush-deck carrier operating aircraft with an AUW of up to 60,000lbs.

The designs were to have a strengthened flight deck forward and amidships to support "50ft diameter launching sites each weighing with pilotless aircraft about 50 tons". There was to be space for four stabilised platforms for missile control radars. (US Aircraft carriers say forward, at either end of the island and on the island itself, whilst the Warship article says that the island and flight deck were each to support two platforms, with the possibility that the lifts might accommodate the radars on the flush deck design.)

A new type of aircraft barrier was fitted with fuel capacity being increased to 300,000 gallons. (The Warship article says it was increased to "the additional fuel capacity suggested in 1945", which was 100,000 gallons.)

The catapults would be replaced, with according to US Aircraft Carriers a H9 catapult with space and weight reserved for a second. (The Warship article says one H8 catapult, and provision for power-driven slotted cylinder catapult.)

Both designs were to have provision for carrying 12,000lb bombs.

Armament was to consist of 10 twin 3"/70 mountings, one at either end, with two in each quadrant. These were to be mounted on large sponsors running three quarters of the length in the ship. The sponsors would free up volume within the design by carrying the ammunition for the 3"/70 battery and other stowage spaces. A 5ft blister (increasing total beam to 103ft) was to run along most of the length of the ship.


In Autumn of 1946 the Flush-Deck Scheme B was selected. By this point both catapults were to be replaced with H9 Catapults with a new flight deck made of 3/4" STS was to be fitted. A ship with a 25ft 6in Hangar would displace 44,000 tons whilst ship with a 17ft 6in hangar would displace around 40,000 tons. Lifts were were to be enlarged to 60ft X 44ft and relocated to the deck edge and aviation fuel stowage was to be increased to 500,000 gallons.

The cost of these conversions was such that in 1947 the decision was made to pursue a more austere design, which became the SCB-27A design that actually entered service.

 

[A Tentative Fleet Plan]

(In this post when I refer to SCB-27A, I will be referring to the design that entered service, not the more capable designs described on my first post.)

In 1949 BuShips were asked to look for cost savings in the carrier modernisations. This design was designated SCB-27B. BuShips suggested that the cost savings could be made by choosing the most modern hulls and limiting improvements to the aviation fuel system, retaining original capacity and increasing the pumping rate from 1500 to 2000 gallons per minute, rather than 4800. The original pair of 250kW generators of the Essex design would retained, where as the SCB-27As received 850 or 1000 kW generators and the new 4ft bulge would be made from Mild Steel rather than STS.

In May 1950 even more austere designs were looked at. These were limited to catapult improvements, barrier redesigns and armament reductions.

A design with blisters installed, and new catapults, arresting gear and barriers, but with flight deck guns removed, and lacking the 5"/50 battery and CCA equipment of the SCB-27As, and an unimproved aviation fuel system would cost $21 million and $26 million for "long hull" and "short hull" ships respectively.

The most austere conversion resulted total elimination of armament, and strengthening the deck edge lift to 30,000lbs to handle the F3H Demon would cost $9 million and require 15 months in a yard.

These were too austere to be approved and the capabilities of SCB-27B began to approach that of SCB-27A. An August 1950 design had everything but the lengthened bow and 3"/50 battery, with a 35,000lb (rather than 30,000lb) deck edge lift. Later a slightly modified SCB-27A was adopted, which had a slight reduction in Electronics and the use of guns transferred from other projects.