One Hundred Years of U.S. Navy Air Power (41 page)

A July 1941 General Board study showed that in addition it would be possible to complete another seven carriers by December 1946 if the twelve on order were all completed as planned by December 1945, giving a potential total of eighteen carriers in December 1945. The board proposed adding four carriers in FY43, both to replace ships reaching retirement age and to make up for possible war losses. However, in September 1941 an OpNav conference decided tentatively to extend the existing program by, among other ships, six carriers (CV 20–25). A somewhat more optimistic BuShips thought it could lay down the carriers between March 1944 and May 1945 and complete them between August 1946 and November 1947. The first two ships (CV 20–21) were ordered in December 1941. They were part of an initial war program (forty-three ships) approved by the Secretary of the Navy between 15 and 24 December 1941.

CNO Admiral Harold R. Stark had already proposed to President Franklin Roosevelt that new ships be laid down as soon as slips were vacated; that way 900,000 tons of combatant ships could be built. Unlike previous authorizations, this one should allow the tonnage to be used however the Navy decided, to reflect war experience. The president himself urgently wanted new carriers. Against considerable opposition, he pushed through the conversion of nine light cruisers to light carriers (the
Independence
-class CVLs). On 14 March 1942 CNO Admiral King proposed extending the building program to produce
Essex
or better carriers at the rate of at least eight per year beginning in 1943, light carriers to make up deficiencies (in the eight per year), and at least two escort carriers (see below) each month. By March 1942 the projected 1943–1944 program included ten
Essexes
plus four of a new type of heavy carrier (which became the
Midway
class). For several months the program shifted back and forth, but in the end it retained these numbers. The
Independence
class became CVL 22–30, the ten fleet carriers became CV 31–40, and the four big
Midways
were listed as CVB 41–44. Remarkably, nearly all Public Domain of these ships were completed before the end of World War II, although one
Essex
(CV-35
Reprisal
) and one
Midway
(the unnamed CVB-44) were cancelled. A further program included three more
Essex
-class carriers (CV 45–47, of which one, CV-46
Iwo Jima
, was cancelled at the end of the war). Two more light carriers (CVL 48–49) were built as such from the keel up, based on a heavy cruiser design. Plans to order
six more
Essex
class (CV 50–55) and two more
Midways
(CVB 56–57) were abandoned in March 1945.

Naval History and Heritage Command

The USS
Midway
in a gale off Sicily, February 1949. Photograph taken from the
Essex-
class carrier
Philippine Sea.

The
Essex
es won the great Pacific battles that broke the Imperial Japanese Navy. They became the core of the postwar U.S. carrier force. Of the twenty-four
Essex
-class carriers completed, one (CV-34
Oriskany
) was suspended at the end of the war and redesigned to operate the new jets.

As a measure of U.S. naval thinking on the eve of war, in September 1941 the Naval War College produced “A Study of the Relative Merits of a Balanced Navy and a Carrier Navy and the Conclusions Reached.”
²⁸
The two-ocean fleet then being built (including 60,000-ton
Montana
-class battleships) was compared to a carrier fleet of equivalent cost built around 60,000-ton carriers (rather than battleships) and 27,000-ton carriers instead of cruisers. It was assumed that bases ashore were more efficient than carriers in operating aircraft, and were also more difficult to knock out. There was no question of building an all-surface ship fleet; the study was intended mainly to show that a fleet without any battleships or cruisers (as some air enthusiasts presumably wanted) would be ineffective in important ways. Heavy guns, for example, were all-weather weapons, whereas aircraft were not. The new U.S. program envisaged half as many carriers as battleships, and more carriers (eleven) had recently been ordered than battleships (nine). War experience certainly suggested
that a combination of carriers and heavy gun ships was needed. Only at the end of the war could massed carriers effectively sink battleships, as in the cases of the Japanese superbattleships
Yamato
and
Musashi
.

WORLD WAR II

U.S. carriers underwent three essential wartime modifications. One was multiple radars: surface and air search and height-finding. A related change, begun before the war, was provision of an aircraft homing beacon. That greatly increased effective striking range, and it permitted a carrier to maneuver much more freely while aircraft were in flight beyond the horizon. The navigation beacon also provided a reference point for scouting aircraft and hence for strikes against the targets they found. A second major change was the Combat Information Center (CIC) which correlated the ship's own data with those from other fleet units and from aircraft. Successful fighter control for self-defense was a consequence of the combination of CIC and radar. The CIC operated manually, and could track only a limited number of targets. In 1945 Japanese kamikaze tactics succeeded because attackers split up far more than had conventional attackers, and CICs were flooded with data. CIC also controlled the ship's own defensive guns, and again the kamikazes tended to saturate the ship's ability to handle targets. The combination of radar/CIC success in 1944 and CIC saturation in 1945 led the U.S. Navy to intensive postwar work, ultimately on automating its CICs in the 1960s. The third major change was of course the proliferation of light anti-aircraft weapons, by 1945 often locally controlled to overcome kamikaze saturation.

Carrier operation changed, too. The prewar idea that carriers should be solitary was dropped as large numbers of new fleet carriers entered service beginning in December 1942. It turned out that up to four large carriers (usually three large and one small) could operate together as a carrier task group, such groups working together to form the fast carrier task force (Task Force 38 or 58 depending on whether the fleet commander was Admiral Halsey or Admiral Spruance).

The kamikaze threat again changed the way carriers operated. Fighters multiplied, so that in 1945 an
Essex
might operate as many as seventy-three of them, her bomber complement cut to fifteen dive-bombers (no scouts) and fifteen torpedo bombers. At this time a more conventional combination was thirty-six fighters, thirty-six dive- and scout bombers, and eighteen torpedo bombers.

By this time the U.S. Navy also operated specialized night fighters. From 1943 on, the Japanese exploited the lack of U.S. night fighters to attack with single medium bombers, which sometimes succeeded in torpedoing U.S. carriers. Initially radar was so heavy that aircraft operated in pairs, a torpedo bomber carrying the radar and directing a single-seat fighter. Then a lightweight night fighter radar was developed,
and carriers were assigned specifically to operate all night fighter air groups. In 1945, for example, USS
Enterprise
was classed as a night carrier, equipped with thirty-seven night-fighter Hellcats and eighteen radar-equipped Avenger torpedo bombers.

ARMORED FLIGHT DECKS

Prewar the British developed a different kind of fleet carrier, with consequences for the U.S. Navy. Believing that carrier fighters could not possibly provide sufficient protection, the British had two choices: they could follow the U.S. practice of trying to kill the enemy's carriers preemptively, or they could design carriers that could ride out air attacks without losing their capabilities. In 1935 the British found themselves facing Italian air strength in the Mediterranean. The Italians used land bases, and there was little possibility that any pre-emptive strike could eliminate the air threat. In 1936, then, the British designed the revolutionary
Illustrious
-class carrier with an armored hangar (including part of the flight-deck overhead). As U.S. designers had told many U.S. officers, there was a considerable price. In this case it was a smaller flight deck and a small hangar, sufficient for only thirty-six aircraft (the previous British carrier accommodated seventy-two). In U.S. terms, the shorter flight deck dramatically reduced the ship's overall aircraft capacity. Later in the war the Royal Navy adopted the U.S. practice of deck parking aircraft, installing a U.S.-style barrier. The short flight deck seems to have caused problems, the British suffering an undue number of accidents when landing aircraft bounced over the barrier to hit the parked aircraft forward. Ironically, the
Illustrious
design proceeded at just about the same time that the British began to develop their own radar, which made effective fighter control possible and thus made the armored hangar, with its limitations, much less important.

The General Board periodically considered armored-deck carriers. In January 1940 it asked C&R for sketch designs. BuAer's strong preference for open-sided hangars (both to warm up aircraft and for athwartship catapults) greatly complicated any such design, because the flight deck had to be a superstructure. C&R's study envisaged moving an inch of armor from the fourth deck (the protective deck in the
Yorktown
s, and the lower protective deck in an
Essex
) to the flight deck, and adding another inch and a half. The price was at least 2,200 tons, about 7.5 feet more beam, and a knot of speed. The 2.5-inch deck could resist ordinary 1,000-pound bombs (not armor-piercing ones), but they could still enter the hangar if they fell at an angle (as they usually did) and came under the flight deck; after all, the hangar could not be protected at all. To move quickly, moreover, the elevators were made of light alloys; they could not retain both their speed and be protected like the flight deck. Much of the added weight came from the massive supports required by the heavy flight-deck structure to withstand the racking stresses of rolling and beam winds.
Too, the topweight would make the carrier heel more steeply on high-speed turns, with unfortunate effects. The idea died—for the moment.

Initially the British kept the armored flight deck secret, but by the spring of 1940 senior U.S. officers were discussing comments on this type of ship by the British Director of Naval Construction—the same Stanley V. Goodall who had helped C&R in 1917–1918. Initial views were that the Norwegian campaign did not show any need for such protection, although it did show a need for naval aircraft with sufficient performance to challenge land-based ones. Since the U.S. war plan against Japan envisaged seizing Japanese-held islands, the idea that no landing could succeed without sea-based air superiority was a very important lesson of the Norwegian campaign. No particular agitation for a U.S. armored deck carrier followed Goodall's remarks, but Captain John S. McCain (a carrier commander), who had pushed for such a ship since 1939, remained its strong advocate through the fall of 1940. One consequence was that in October 1940 the British were asked for details of the armored carriers. Meanwhile BuShips studied future carriers armored much like
Essex
but with heavier gun batteries (one had 8-inch guns), responding to an August 1940 General Board request. One was armed with the new 5-inch/54 dual-purpose gun, then in the concept stage. By June 1941 it had been developed into a sketch of a 44,500-ton carrier. Its future significance was that it became the basis for a study of a carrier with a protected hangar, which in July 1941 the preliminary designers were about to start. At a June 1941 General Board hearing, the Chief of BuAer suggested building this ship if the decision were taken to replace the planned 65,000-ton
Montana
-class battleships with aircraft carriers. This CV-A would have been 900 feet long, protected against 8-inch cruiser guns. Given her size, she would have accommodated more aircraft: the usual thirty-six fighters, plus thirty-eight dive-bomber/scouts and thirty-eight torpedo bombers. BuAer saw much larger carriers as the only way to retain existing numbers while adopting larger higher-performance aircraft.

Illustrious
suffered heavy dive-bombing in 1941 and was sent to Norfolk Navy Yard for repairs under the Lend-Lease program. There she made a considerable impression on U.S. officers—who did not notice that the German armor-piercing bombs actually had made such a mess of her flight deck that she could not keep operating. Those defending U.S. design practices said that the British ship was far better for European waters but that an American-type carrier with many more aircraft made much more sense in a lengthy Pacific campaign. U.S. officers wanted both an American-style air group and British-style protection, accepting that the result would be a larger ship (now unrestrained by treaty, with much relaxed financial limits, too). By July 1941 BuShips had details both of the
Illustrious
design and of the damage she had suffered. The Royal Navy had built a carrier with an armored hangar, not one with a full-length armored flight deck. A heavy German bomb penetrated her hangar roof (part, but not all, of her flight deck) and gutted her hangar.
Because the hangar did not run the full length of the ship, had the bomb hit slightly further forward it would have penetrated deep into the ship, with disastrous consequences. On the other hand, the armor forced the Germans to use a large bomb, and that in turn reduced the scale of the attack, because not all German aircraft could have conducted the attack. Under similar circumstances an
Essex
would also have survived, although the hangar deck might have been penetrated. BuShips developed several designs showing what an
Essex
-like carrier would have to sacrifice to gain some degree of hangar protection. For example, a 28,000-ton carrier (CV-D) with 2.5-inch armor on her flight deck (
Illustrious
had 3 inches) would operate sixty-four aircraft rather than the eighty-three then credited to the
Essex
, and would make 31.5 rather than 33 knots. In November 1941 BuShips offered CV-E, enlarged so that in effect she made no sacrifices to gain a 3.5-inch armored flight deck. She had a 2-inch armored hangar deck. As in the earlier studies, adding armor so high in a ship made for much larger size; in effect the armored flight deck equated to the 8-inch guns of the CV-A study. Given her sheer size, she could operate six squadrons of existing types of aircraft.