One Hundred Years of U.S. Navy Air Power (39 page)

Although a sketch design was prepared in 1931, there was no money for new construction until the Roosevelt administration passed the National Industrial Recovery Act in 1933. It provided money to build two ships:
Yorktown
and
Enterprise
, completed in 1937 and 1938, respectively. Meanwhile the hangar deck powder catapults were abandoned, although interest in hangar deck catapults survived. BuAer meanwhile developed a successful hydraulic catapult that could be mounted flush on the fore end of the flight deck. It was so attractive that special measures were taken to save enough weight to fit it within the 20,000-ton displacement limit. The new ships had three such catapults, two on the flight deck and one (athwartships) on the hangar deck.

Initially (1933) the new carriers were designed to operate ninety-four aircraft: eighteen fighters, thirty-six scout bombers, eighteen torpedo bombers, eighteen bombers (heavy dive-bombers—a category soon to be filled by the Northrop BT, predecessor of the Douglas SBD Dauntless), and four utility aircraft. The scout bombers were capable of dive-bombing with light bombs (500 pounds), but they were primarily scouts. The flight-deck spot could not accommodate all of them; typically nine torpedo bombers had to remain in the hangar when all the others were on deck. Even then operation was marginal; the first fighter in line had only 116 feet of deck in which to take off, but in a twenty-five knot wind the most efficient such airplane (XF3U, with a controllable-pitch propeller) needed 143 feet, not including the usual 25 percent safety margin. BuAer strongly argued for a deck extension. It was clear by 1934 that with their full air complement the ships could not employ the standard spot in which the after arresting gear was clear for landings and the forward length clear for takeoff. Worse, there was not sufficient hangar deck space for those that could not fit on the flight deck. By World War II the bomber (heavy dive-bomber) and scout bomber categories had merged, and airplanes were considerably larger, so the ships were expected to operate four eighteen-airplane squadrons: fighters, scouts, dive-bombers, and torpedo bombers, for a total of seventy-two combat aircraft. Because they carried the heaviest weapons, the torpedo bombers were also considered suitable for level bombing (mainly for land attack) with heavy bombs.
²³

With the
Yorktown
design BuAer accepted that an island structure was not merely a necessary evil, but that it presented a vital means of controlling the flight deck. By 1932, with
Ranger
nearly complete, the bureau badly wanted her modified to incorporate an island. It was far too late to lead smoke pipes up through the small new
island, but the structure did provide a conventional bridge (that incidentally reduced congestion in the forward part of the hangar) as well as positions for two directors, which made the ship's 5-inch guns far more effective. The
Ranger
island was in effect the island structure planned for the
Yorktown
s less their massive funnels.
²⁴

In effect these ships were pre-prototypes of the mass-produced
Essex
class of World War II. Investing in them showed just how important naval aviation was to the interwar Navy. They proved extremely tough.
Enterprise
fought in nearly every Pacific battle and survived the war.
Yorktown
was sunk at Midway.

There was not enough tonnage for a third ship, so the General Board suggested a 15,200-tonner (32.5 knots, like the 20,000-tonner) for the next (1934) program. Construction was delayed because the tonnage involved was absorbed by the obsolescent
Langley
. In 1937 she was de-rated to seaplane tender status, hence removed from carrier tonnage. A much-improved
Ranger
, USS
Wasp
, was built (by this time available tonnage had dropped to 14,500). Like the
Yorktown
s, she had a massive island. Again, limited tonnage meant limited speed and also limited survivability. In
Wasp
as in earlier carriers, there was interest in flying aircraft from the hangar deck to increase the rate at which they could be launched. She was completed with two hangar deck catapults in addition to two flight-deck catapults. As with other carriers,
Wasp
was given an enlarged fighter squadron (twenty-seven aircraft) in 1940. For the rest she had a standard air group at the beginning of World War II: a scout squadron, a scout bomber squadron (dive-bombers), and a torpedo squadron, but by 1942 the torpedo squadron was twelve rather than the usual eighteen aircraft. The scouts and dive-bombers were the same SBD airplane, but their roles were quite different. Although the 15,200-tonner conceived in 1931 would have had the power and speed of the
Yorktown
s,
Wasp
was laid down with a 70,000 rather than 120,000 SHP) plant and a designed speed of 29.5 knots (
Ranger
produced only 57,000 SHP.

Toughness meant the carriers were difficult to sink, but it was widely understood, in the 1930s, that their flimsy flight decks could easily be destroyed by light bombs. Although the phrase “eggshells wielding hammers” was coined to describe contemporary heavy cruisers, carriers were best described in this way, particularly as their offensive power grew during the 1930s. It was assumed that whichever side found the enemy's carriers first would put them out of action. After a war game, for example, Admiral King, commanding the Battle Fleet Aircraft, was asked by battleship officers why his ships were not providing them with air services (such as protection for their spotting aircraft). They seemed to fight a private carrier versus carrier war in every fleet exercise. King replied that unless his carriers defeated the enemy's at the outset, the battleships would never have any air services at all. Given this perception, through the 1930s U.S. carrier officers asked why future carriers could not be provided with at least lightly armored flight decks.

The answer says a great deal about contemporary U.S. thinking. An armored flight deck would represent considerable topweight, even with thin armor. On a given displacement (limited by treaty), that topweight could be accommodated on a smaller hull with a smaller air wing. The alternative, unavailable at the time, would be to provide much the same air group by growing the hull to balance off the topweight involved. The smaller-carrier solution was regularly rejected because it was so important both to find and to kill enemy carriers. U.S. carriers were expected to operate alone, so each carrier had to be able to conduct all these functions. Finding an enemy required a squadron of dedicated scouts. Killing an enemy required a squadron of dive-bombers, preferably accompanied by a squadron of torpedo bombers—and by fighters. Four squadrons—more than eighty aircraft—required a large flight deck, hence a large carrier. The scouting (S) and dive-bombing (B) roles were combined in single airplanes by the late 1930s, but they were still separate functions and they still required separate squadrons. Thus by the outbreak of World War II, U.S. carriers typically accommodated two squadrons of scout bombers, such as the Douglas SBD Dauntless.

In the late 1930s the big Fleet Problem exercises awakened the fleet to the desperate need for direct fighter protection; there was only limited faith in anti-aircraft guns, and it seemed that only fighters (if anything) could deal with the dive-bombing attacks the U.S. Navy itself favored. Yet the single squadron of fighters aboard each carrier was considered part of that ship's own anti-aircraft screen, or as protection for the ship's own striking force (both the war in China and the Spanish Civil War seemed to show that such protection was essential). The standard carrier squadron of eighteen fighters already included nine spare aircraft to allow for attrition and to maintain full operating strength when some aircraft were being overhauled. Up to three of these “operating spares” were normally used that way. Commander, Aircraft Squadrons Battle Force Rear Admiral Ernest J. King (later the wartime CNO) proposed using spares to strengthen fighter squadrons on board the large carriers to twenty-four active aircraft. The Scouting and Battle Force commanders wanted a lot more. Ultimately the recommendation was to give the two slow carriers (
Ranger
and
Wasp
), which would probably work with the battle fleet, fighter-heavy air groups, leaving the big fast carriers, which would probably operate as independent striking forces, with their original air groups, tilted toward attack rather than defense. After all, if it was accepted that an air attack once launched could not be stopped, the only real fleet air defense against enemy carrier aircraft was to destroy them at source—at the enemy carrier. As for the strike carrier's own fighters, normally they would form a continuous combat air patrol. Maintaining it would exhaust the pilots, who would be unable to escort the carrier's bombers once the enemy fleet was found. Note that search radar could change this situation; the carrier might have to mount a combat air patrol only after enemy aircraft were detected.

Ships already had the capacity for twenty-seven fighters; they just normally did not carry enough pilots. In June 1940 BuAer proposed that the fighter squadrons be boosted to twenty-seven airplane strength, and OpNav agreed. By that time the agreed characteristics for the next carrier class (
Essex
) already incorporated an interesting twist: they should have the usual four eighteen-airplane squadrons, but also space to accommodate a fifth (fighter) squadron of eighteen aircraft. Given pressure for more fighters, the bureaus interpreted this to mean five squadrons of planes with their personnel, stores, guns, and ammunition rather than the spare planes previously imagined. This new interpretation certainly comported with the twenty-seven fighter concept approved in June 1940; the new
Essex
had sufficient capacity for a double fighter squadron (thirty-six aircraft).

Surviving papers do not mention radar as a factor in these changes, but it is difficult to discount, because it solved a serious problem. Through the 1930s hopes that the carrier's own fighters could protect her against enemy attack had declined. About 1930, U.S. thinking envisaged a circular formation in which destroyers many miles from the carrier could spot approaching enemy aircraft in time for carrier fighters to take off and deal with them. Through the 1930s aircraft performance improved dramatically, to the point that it was no longer possible to set up a satisfactory screen (that proved difficult enough even
with
radar). Some suggested abandoning carrier fighters altogether. They survived mainly as a means of supporting strike aircraft (with light strike capability) and also as a means of supporting the Marines should they have to land on enemy islands (a role already being taken very seriously). The advent of radar in 1937–1939 changed the situation completely. Suddenly it became possible to provide effective warning, even against fast aircraft. Radar was first tested in the January 1939 maneuvers, aboard the battleship
Texas
. It did take considerable time for the U.S. Navy to turn this raw technology into an ability to control fighters. At Midway a carrier versus carrier battle developed much as had been predicted. U.S. strike aircraft found three Japanese carriers before the Japanese found the Americans and inflicted fatal damage. Then the surviving Japanese carrier found an American carrier, USS
Yorktown
. Her aircraft managed to damage
Yorktown
fatally (she sank due to loss of power and inability to de-water after numberous Japanese hits). The U.S. ships had radar, but they also had only very primitive fighter control arrangements. Two years later, at the Philippine Sea, the Japanese found the American carriers first. However, the U.S. ships had highly developed fighter control based on the new technology of the Combat Information Center (CIC). The Japanese air striking force was massacred in the “Turkey Shoot.” It happened that most Japanese carriers themselves survived. One irony of the battle was that the U.S. aircrews thought they had done poorly; Samuel Eliot Morrison reports a feeling of depression on the hangar decks. In fact they had ended the Japanese naval air arm, because the Japanese could never train replacement aircrew—a fact not appreciated a few months later at
Leyte Gulf. The core issue was aircrew more than carriers: the great strength of the U.S. Navy lay not only in its ability to multiply carriers and their aircraft but even more in its ability to multiply aircrew.

The Washington Treaty (and its successor, the London Treaty of 1930) affected the U.S. Navy in a subtle way. Until 1934 U.S. warships were individually authorized by Congress. That year Japan withdrew from the treaty system, and a few in the United States realized that war might be coming. Congress passed the Vinson-Trammell Act, which authorized a “modern Treaty Navy.” This phrase avoided the appearance of expansion, but allowed considerable new construction, because the United States was well below the allowable tonnage. (Congress still decided how much money to appropriate, thus still controlled new construction.) By 1936 it was clear that Japan was no longer interested in any kind of limitation, but there was still hope that a treaty system might limit naval spending and indirectly avoid war. To that end the replacement London Treaty eliminated the tonnage totals on battleships and carriers, but it retained limits on individual ship size (the carrier limit was reduced to 23,000 tons, at British insistence). Signatories had to announce their naval building plans well ahead of construction, the idea being that they would restrain themselves to avoid touching off a building race. Given the form of the Vinson-Trammell Act, as the international situation worsened Congress authorized a percentage increase in various categories of treaty-limited warships in the Second Vinson-Trammell Act (1938).
²⁵
Because battleship and carrier tonnages were tied back to the Washington Treaty, the Act implicitly maintained much the same ratio between the two types—which had reflected the much earlier experience of World War I. The phrase “modern Treaty Navy” meant that new construction was approved to replace existing overage ships, replacement age having been set by treaty. In 1936 the only over-age U.S. capital ships were battleships. U.S. carriers were all far too young to replace in the near term.