One Hundred Years of U.S. Navy Air Power

by Smith, Douglas V.

  NEW CARRIERS—NEW AIRCRAFT

  Even before the end of World War II the U.S. Navy convened a panel of experienced officers to ponder the future of the carrier, which it now saw as its primary weapon.6 Panel members soon concluded that the main value of a future carrier would lie in its ability to deliver heavy bombs against land targets. A carrier could not accommodate many heavy bombers, but it seemed that relatively small numbers of heavy bombs delivered on a precision basis might be quite effective. Moreover, heavy bombs seemed to be the only effective antidote to the coming new generation of submarines. By spring 1945 the main characteristics of new German submarines (which it was assumed the Soviets would copy) were known, and they could clearly overcome most World War II convoy escorts. The submarines could, however, be destroyed in their pens. It seemed likely that the Soviets would adopt the wartime German practice of building heavily protected pens, hence the need for very heavy bombs to deal with them. It happened that a carrier-based heavy bomber could also drop atomic bombs, but that does not seem to have been the key consideration, at least initially.

  The panel drew up a rough specification for a future carrier-based heavy bomber. A study by the Bureau of Aeronautics defined the largest bomber that could be launched by existing carriers, using their catapults. It fell far short of the ideal, but it was still worthwhile, and in December 1945 it was ordered as the North American AJ Savage.7 President Truman agreed that the Navy should share the nuclear mission with the Army (hence with the Air Force established in 1947), thus the Savage design was modified in spring 1946 so that it could carry an atomic bomb. Meanwhile the Navy sought an interim nuclear attack capability. It had a new high-performance land-based patrol bomber, Lockheed’s Neptune (P2V, later P-2). A Neptune could certainly deliver the 10,000-pound atomic bomb. Given sufficient boost, in the form of rockets, it could take off from the long flight deck of a Midway-class carrier. Neptunes and the carriers together amounted to an interim Navy nuclear attack system. The big airplanes were given tail hooks, but attempts to land them aboard a simulated carrier failed. In war, they would have been placed aboard their carriers by crane; they would have ditched on returning from their missions.

  The limitations of the Savage and the Neptune were indications that existing carriers were too small for the key postwar mission. A rough specification was drawn up for the desired long-range bomber. The Bureau of Aeronautics (BuAer) produced an outline design as a guide to designing a carrier that could accommodate such aircraft. Meanwhile two much more ambitious specifications were released to aircraft companies.8 One specification called for a long-range bomber fast enough to evade existing fighters. Maximum takeoff weight was 100,000 pounds, beyond what existing carriers could support; but some of the designs offered could operate from existing ships if they could be fitted with more powerful catapults. The second specification called for supersonic speed over the target, presumably to ensure immunity from interception. Nothing short of a much larger carrier could support such aircraft.

  The main features of the special carrier were a very large flight deck without obstructions (a flush deck) and very powerful new catapults. The flush deck made it possible for the carrier to operate aircraft with long wingspans, which might otherwise collide with a ship’s island.9 Both involved technical problems. It would not be easy to vent the smoke produced by the ship’s huge power plant, and a flush deck would greatly complicate placing the radars on which the ship would rely (for a time it seemed that radar and command facilities would be transplanted into an accompanying ship). Existing catapult technology was hydraulic, but the wires and sheaves such catapults used (to multiply the stroke of the hydraulic piston) could not take anything like the loads envisaged. The Bureau of Aeronautics became interested in a new technology, a cylinder whose piston would be moved by explosives.10

  Perhaps the single greatest design problem was to provide a flight deck heavy enough and strong enough to accommodate aircraft weighing as much as ten times wartime types. The solution was to abandon the previous practice of building a light flight deck as a superstructure atop a hull. Instead, in the new carrier the flight deck was the upper strength element of the hull girder (especially creative solutions were needed to carry strength around the massive holes cut in the side of that girder). Given this approach, centerline elevators were abandoned. Initially it seemed that the new special-purpose carrier would have no hangar at all, her heavy bombers carried permanently on deck, but that idea was soon abandoned. Even placing the slots for catapults in the strength deck was a problem, but it could not be avoided. The ship was designed with four catapults, rather than the two of wartime carriers: two in the bow to launch heavy bombers, and two smaller ones in the waist to launch fighters or smaller bombers. The catapults were so spaced that airplanes could have been launched simultaneously from waist and bow catapults, to get an attack force into the air as quickly as possible (presumably in the event the ship was attacked).

  By 1948 it seemed that the design of the new carrier was mature enough. It may also have seemed that this would be the Navy’s last opportunity to decide for itself what it needed—before Service unification put much power in the hands of the Secretary of Defense and, more importantly, a Joint Chiefs of Staff dominated by the two ground Services, the Air Force and the Army. Surviving records suggest that neither of the key technical problems, the use of the flush deck and the catapult, had been solved. That was by no means obvious at the time.

  The Navy did not expect to have many of the new carriers; the usual figure was four (or fewer). Navy plans called for modernization of existing carriers to form new task groups built around the heavy carriers. The existing carriers would operate jet fighters to protect the attack carriers when they conducted their strikes against Soviet targets. A task group would consist of one heavy carrier plus three smaller ones, for a total fleet of four new type carriers, three Midways and ten modernized Essex class. Modernization for jet operation involved provision of much more fuel (jets were very thirsty), new heavier catapults (still hydraulic, hence within existing technology), and new arresting gear. In an Essex, the flight deck would be cleared to some extent by eliminating the gun mounts placed there and by shrinking the size of the island. The Essex-class carrier Oriskany, incomplete at the end of World War II, was suspended, redesigned, and rebuilt as the prototype of the modernized design, under SCB Project 27A. Modernization of the Midway class was deferred, probably because all three were badly needed to support the interim capability in the form of the Neptunes.

  When he cancelled the new carrier on 23 April 1949, Secretary of Defense Johnson shifted the money to Essex modernization. He ordered the more visionary bomber designs cancelled, but he allowed a more conservative design, which could (in theory) operate from a modernized Midway, to proceed. It became the A3D (later A-3) Skywarrior. It was not obvious at the time that the BuAer catapult project was not very successful. In effect the cancellation of the supercarrier delayed that realization. However, to operate a Skywarrior from a Midway-class carrier required the new catapult. In 1950, as the big bomber approached its first flight, the catapult became the decisive item in the necessary Midway-class modernization, as without that modernization the Navy would never get its jet strategic bomber.

  As defense funds shrank in 1949–1950, the Navy was ordered to lay up more and more of its attack carrier force. In spring 1950 it must have seemed that only antisubmarine forces would soon be left. Carriers certainly figured in such forces. Beginning in 1946 the U.S. Navy experimented with two captured high-speed U-boats, and soon it produced its own fast submarine in the form of the Guppy conversion of its fleet type. One possible counter to such submarines was to hunt them down. It was assumed, for the moment, that wartime HF/DF methods would provide the necessary wide-area surveillance (direction finding), and a pair of experimental task groups was created, built around a light carrier and a large escort carrier. This idea was so important that new specialized ASW aircraft (the AF Guardian) were
developed on the basis of a late-war Grumman torpedo bomber (TB3F). There were two complementary roles: a hunter carrying sonobuoys and a big surface-search radar (to detect snorkels) and a killer, carrying one or more homing torpedoes. The wartime airframe was too small to combine the two roles, and it seemed that the available small carriers could not have supported anything much larger (even the Guardian was a difficult fit). However, in 1950 the Bureau of Aeronautics issued a requirement for a single-package (hunter and killer) carrier airplane, suitable to operate from the Commencement Bay–class escort carriers. Several companies offered single-engine aircraft, but Grumman won with a small twin-engine design, the S2F (later S-2) Tracker. A new CVE was included in the FY52 program, but it was not built. Several war-built escort carriers and light fleet carriers were modified for ASW.

  The idea that future U.S. ASW would rely heavily on carrier aircraft cued by a wide-area surveillance system was established, and it shaped much of what carriers would do over the next decades. By the time the Tracker was ready, it was clear that not all Essex-class carriers would ever be modernized. Those not modernized were placed in a kind of second-class status as ASW carriers (CVS), operating in ASW task groups in the Atlantic and the Pacific. The carrier ASW mission survived because beginning in 1956 the United States had a new underwater ocean surveillance system (SOSUS) that could cue hunting aircraft both from carriers and from shore bases.

  At this point there was little interest in providing the big strike carriers with their own ASW aircraft. It was assumed that their high cruising speed (over twenty knots) would give them effective immunity against even the fast submarines the Germans had deployed in 1945 (which the Soviets were expected to copy).

  With the Korean War the project for a big carrier was revived, although at least in theory it was a flexible tool of limited war rather than a strategic weapon. The first of the post–World War II carriers, USS Forrestal, began as a slightly reduced version of the abortive supercarrier of 1949, USS United States, with the same flush deck and the same catapults.11

  The close World War II relationship with the Royal Navy, the only other major carrier navy in the world, survived the end of the war. Royal Navy interest in heavy air attack was quashed by the Royal Air Force, which argued that the string of Commonwealth and Empire air bases made strike from the sea unnecessary. The Royal Navy found itself concentrating on sea control, largely in the seas close to Europe—hence close to Soviet naval bomber bases. The British military therefore considered air warfare key; it had to learn to operate jets from carriers much smaller than those of the U.S. Navy, and it had little chance of building supercarriers. These considerations forced the Royal Navy into innovation, from which the U.S. carrier force benefited enormously.

  One idea was that aircraft could land on flexible (inflated) decks, without using landing gear. It appeared that an airplane might save substantial weight in this way, weight that could translate into higher performance. The British tested the flexible deck, and for a time it seemed the U.S. Navy might adopt it, but its problems (such as moving the airplane around the deck after it landed) were never really solved. The flexible deck did lead to a further, much more important idea. A British officer pointed out that the carrier landing area did not have to lie along the centerline of the flight deck; it could be angled to one side. That would simplify aircraft handling, since a crane could lift a landed airplane off the deck to clear the landing area. The prospective Commanding Officer of the new carrier Ark Royal suggested that this angled deck idea be applied to his ship.12

  The angled deck would solve a major carrier problem. Landing aircraft sometimes bounced over the barrier to crash into the parked aircraft forward; the relatively small British carriers suffered particularly badly. Existing barriers, moreover, were ill-designed for jets. They were wires intended to stop a bolting airplane by winding around its propeller. A jet hitting the barrier would run the wire up over its nose to decapitate its pilot. Work was proceeding on a nylon net barrier to stop jets, but the angled deck solved the problem far more elegantly. If the airplane did not snag the arresting wires, it could simply power up and fly off the fore end of the angled deck. There was some question as to whether pilots could maneuver properly to land at an angle to the ship’s centerline, but trials showed that was no problem. The U.S. Navy enthusiastically adopted the angled deck, more readily than did its inventor, the Royal Navy. The British were worried about operating relatively small high-performance aircraft, but the Americans had to operate very large aircraft—for them the greatest advantage of the angled deck was that it carried such aircraft well clear of the carrier’s island. Thus the angled deck instantly solved the flush-deck design problem by eliminating the need for such a deck. The angled deck was tested in primitive form aboard USS Midway and then in more complete form aboard USS Antietam. Already under construction, Forrestal was quickly redesigned with a conventional island. Ironically, both she and the abortive United States had large sponsons angled out from their flight decks; they could easily have accommodated British-style angled layouts, but the arresting gear was never placed for such operation.

  The small size of British carriers made catapults even more important than they were for the U.S. Navy. The U.S. problem was to launch super-heavy bombers. The British were more interested in high-performance fighters, with high stalling speeds. Jets needed catapults because they did not develop sufficient thrust for takeoff on a short deck (the power of a jet engine depends on how fast the airplane is moving, so jets need long runways to accelerate). A British catapult developer, Colin C. Mitchell, became interested in the steam catapult the Germans had developed to launch their wartime V-1 missiles. There was apparently no British interest in the explosive catapult the U.S. Navy was then developing; Mitchell’s steam catapult was the alternative to the earlier (and too limited) hydraulic units and also to the wartime practice of sometimes using booster rockets (JATO) for takeoffs.

  Initially the U.S. catapult developers showed little interest in the British steam catapult. By 1952 their situation was critical, because the heavy attack bomber that had survived the 1949 cuts was about to enter service. There was an urgent project to modernize the Midway-class carriers to accommodate it. The air branch of OpNav demanded quick action, and the U.S. naval attaché in London (an aviator) made sure that details of the steam catapult reached Washington. Ultimately he arranged for demonstrations by the British steam catapult test carrier. U.S. catapult developers maintained that the explosive catapult would ultimately succeed, but the steam catapult was a most satisfactory substitute. In effect the steam catapult and the angled deck made it possible for carriers to operate aircraft entirely equivalent to contemporary land-based types—they ensured the survival of carrier aviation. It appears that prior to the steam catapult episode, U.S. naval aviators showed little interest in British innovations, considering their own technology entirely superior. With the adoption of the steam catapult, this attitude reversed, probably accounting for the quick adoption of the angled deck.

  A third British innovation can also be traced to the problem of small carriers. The British aircraft test establishment (Farnborough) analyzed in great detail the problem of landing high-performance jets. By the end of World War II the Royal Navy used the U.S. system, in which a Landing Signal Officer (LSO) watched the descending airplane. He signaled the pilot to correct errors and then to cut his engine while he was still in flight just prior to snagging the wire of the arresting gear. Thus the pilot and LSO were part of a feedback cycle. The faster the approaching airplane, the tighter that cycle should be—but it was limited by the reaction times of the pilot and the LSO. A British engineer realized that the pilot had to make his own corrections, based on something he could see, rather than on the LSO’s observations. Using a paperclip and a makeup mirror, he proved to himself that a pilot could do what was needed on the basis of what he could see in a stabilized mirror mounted alongside the flight deck. This idea was quickly adopted (in modern form
a Fresnel Lens replaces the mirror). The pilot watches banks of lights to indicate whether he is too high or too low or on the correct glide path. Again, the mirror landing sight was key to using high-performance jets on board carriers.

  Angled decks and steam catapults were installed on board the three Midways and also on board modernized Essex-class carriers (as SCB 27C). The modernized carriers also received enclosed (“hurricane”) bows; the idea may be traceable to the damage suffered by the carrier Bennington during a severe storm. U.S. carriers had suffered similar flight deck damage during the great 1944 typhoon, but that seems not to have affected early postwar designs such as SCB 27A and United States.

  Forrestal was followed by three very similar ships (Saratoga, Banger, and Independence). All represented the simplest possible redesign of the original flush-deck carrier, with elevators arranged so that one would feed each of the four catapults. When the angled deck was introduced, the forward elevator on that (port) side was relocated aft on the starboard side. It was soon clear that this arrangement was unfortunate, and in the fifth postwar carrier (Kitty Hawk) the positions of island and elevator were interchanged.

  Convinced of the value of these powerful carriers, the Eisenhower administration adopted a policy of building one each year.

  By this time another new technology, nuclear power, was nearing maturity. A carrier was a natural application; the first program for systematic reactor development (1955) included large surface ship plants for carriers and cruisers. Nuclear power offered effectively unlimited high-speed steaming, which in turn would make submarine attack nearly impossible (prior to the advent of Soviet nuclear submarines backed by ocean surveillance systems). The severe corrosion due to stack gases would be eliminated. Stack gases also affected aircraft approaching the carrier by reducing visibility. Because a nuclear carrier would not produce any smoke, her design became an opportunity to rethink the position of the island and hence carrier configuration. Possibilities included a pair of angled decks, one on each side of the island, crossing at the bow, and a two-deck configuration reminiscent of some prewar British carriers. Ultimately all these possibilities were rejected, and the nuclear carrier used much the same flight deck configuration as Kitty Hawk (CVA-63). To attain the required power, the new ship needed eight reactors, all linked together into a single power plant. This massive structure in turn demanded a larger hull (not least for buoyancy), so the resulting Enterprise was considerably larger than the Forrestals. One unexpected feature of the design was a vast aircraft fuel capacity: fuel was part of the side protective system defending against torpedo hits, and the sheer size of the hull made for a larger system and hence for more tankage. The nuclear carrier was considered experimental, so the next carrier (USS America, CVA-66) was essentially a repeat version of Kitty Hawk.