America’s Emergency Carriers
by Mike Bennighof, Ph.D.
September 2008

Whether President Franklin D. Roosevelt ever seriously thought the United States could lose the Second World War is doubtful; that he grew concerned that the Japanese and Germans could make it longer and costlier than necessary is fairly obvious. A former Assistant Secretary of the Navy, Roosevelt paid especially close attention to the Navy’s building plans, and in August 1941 agitated for more aircraft carriers.

The many hulls being laid down for Cleveland-class light cruisers, the commander-in-chief argued, presented a useful resource for quick acquisition of new carriers. The Bureau of Ships countered that the new Essex-class fleet carriers would be available much faster than the president seemed to think, and the converted cruisers would not make very good carriers. In the weeks following Pearl Harbor FDR seemed completely vindicated, and the Navy eventually ordered nine cruiser hulls turned into light carriers.

All nine of what would become the Independence-class light aircraft carriers are present in Second World War at Sea: Leyte Gulf. They are much less capable than the big fleet carriers, but with the very powerful American aircraft on their decks, one of them is equal in fighting power to anything the Japanese have.

Launching CVL23 Princeton, October 1942.

The Chief of Naval Operations issued orders on 2 January 1942 at Roosevelt’s direction; New York Shipbuilding received a formal authorization for the first conversion on 10 January. Plans were submitted on 2 February and approved on the 10th.

This rapid turnaround resulted from years of prior planning. The Navy had never been satisfied with its first pair of “Treaty cruisers,” the 10,000-ton Pensacola class. Attempted sales of the two ships to South American navies and to Sweden fell through thanks to the worldwide Great Depression, and as early as 1926 a design study looked at turning the then-incomplete cruisers into small aircraft carriers.

Naval engineers liked the hull design of the Brooklyn-class light cruiser, laid down starting in 1934. Even though Savannah suffered serious storm damage to her bow in 1939, probably due to steps taken to reduce weight, the Brooklyn hull would form the basis of several later classes of cruisers. During the 1930s, several design studies looked at using the Brooklyn hull as the basis for combination cruiser-carriers.

Along with these “flight deck cruisers,” the Bureau of Ships also prepared plans for a high-speed commerce raider/convoy escort with four 14-inch guns on a Brooklyn hull, and a through-deck carrier.

The flight deck cruiser never went into a Navy budget, though it came very close to authorization. The heavily-gunned cruiser stayed where it belonged, on the drafting board. But the full-decked carrier design, finished in July 1938, received very good marks from the General Board as a slightly smaller version of the carrier Wasp. The Board felt, however, that the small carrier would have difficulty conducting air operations in bad weather or heavy seas where a full-sized fleet carrier would not.

Thus, when Roosevelt made his pitch for cruiser conversions, a ready-made set of plans lay waiting for authorization. The Cleveland design was based on the last pair of Brooklyn-class ships, Helena and St. Louis, which had a different machinery arrangement and superstructure than the rest of their class, and had their five-inch guns mounted in twin gunhouses. The Cleveland design took into account the greater threat from air attack, losing one of Brooklyn’s five 6-inch gun turrets (reducing the number of guns from 15 to 12) but raising the number of dual-purpose 5-inch weapons from 8 to 12 and fitting a much larger array of 40mm and 20mm automatic weapons.

Four ships were laid down in 1940; by the end of 1941 a total of 13 new cruisers had been laid down and 21 more orders placed. The fifth ship of the class, Amsterdam, had been laid down at New York Shipbuilding’s Camden, New Jersey yard in May 1941 and was selected for the first carrier conversion. She was almost 40 percent complete when workers began removing her superstructure. The plans got such good marks from the admirals that two more cruisers under construction in Camden, Tallahassee and New Haven, were earmarked for conversion.

Arming an Avenger torpedo plane aboard San Jacinto,
during the Battle of Leyte Gulf.

In March 1942, the CNO’s office ordered Huntington, Dayton and Fargo converted as well. The first two had been laid down in Camden in December 1941 and were not yet very advanced, so nothing had to be removed from them. Fargo had not even been laid down, and the Navy transferred her contract from Federal-Kearny (which had already earned the Navy’s wrath over problems with Buffalo of the same class) to the Camden yard.

The total came to nine in June when the Navy ordered Wilmington — laid down in March as a cruiser — completed as a carrier, and two other not yet begun, Buffalo (her contract having been yanked from Federal) and Newark, converted as well. Thus three of the light carriers were not true conversions at all, as they had already been ordered as carriers when laid down.

Roosevelt had believed the Navy would desperately need the small carriers, but thankfully events proved him wrong. All nine of them completed during the course of 1943, from Independence (the former Amsterdam) in January to San Jacinto (ex-Newark) in December.

Two of the small carriers lost their cruiser armor, but the other seven retained it. Over their 600-foot hull, a flight deck 570 feet long was erected. The 1938 plan called for a flush-decked carrier without an island, but the small island designed for the Bogue-class escort carriers was fitted well forward on the starboard side. The light carriers received hull blisters to improve stability, and displacement rose from 10,000 toms to 15,387. They had two aircraft elevators on the centerline, and a single catapult (late increased to two after some heated discussions). Independence underwent trials with two 5-inch guns, but had them replaced by two quadruple 40mm mounts after her commander argued that the two guns would do little to protect the carrier from surface attack, for which she should rely on her escorts. The other eight completed that way.

Lt. j.g. Alfred Magee escapes his burning F6F
just after landing on Cowpens, 24 November 1943.

The Bureau of Aeronautics set the air group at 31 planes — 12 fighters, nine dive bomber and nine torpedo bombers, plus one utility plane. In practice, the carriers often operated air groups completely composed of fighters, and Independence esclusively operated night fighters for much of 1944.

In service, the ships performed very well and all nine of them formed part of Third and Fifth fleets during the last two years of the Pacific War. Board members had been concerned that they could not operate the big Avenger torpedo bombers, but despite some cramped spaces the small carriers handled the planes. Princeton, the second ship of the class, was lost during the Battle of Leyte Gulf when a single Japanese land-based dive bomber penetrated the American fighter screen.

The Navy liked the design very much, and commissioned a follow-on light carrier based on the bigger Baltimore-class cruiser hull, the Saipan class. But the small ships could not operate the bigger and bigger airplanes the Navy received after the war, and as early as 1946 Independence was expended in the atomic bomb tests at Bikini Atoll. Two of the class were sold to France, and two others had brief post-war careers as anti-submarine carriers (one of these going to the Spanish Navy in 1967).

This piece originally appeared in June 2005.

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