Evolution of aircraft carriers XIII: The turbulent post-WW II years
Thirteenth article in a series by Scot MacDonald. Reprinted with permission Naval Aviation News, October 1963 pp. 64-68.
There has been a spectacular advance in aircraft design technology. The transition from propellor-driven aircraft to jet power has been fast. We are now undergoing another evolution from subsonic to supersonic speeds at higher altitudes…By modernisation we have utilised our assets of World War II Essex class carriers to the maximum. This has been a military necessity in order to maintain an acceptable degree of combat readiness economically in about half the time required for new construction. Carrier modernisation has been pushed vigorously.—ADML Arleigh Burke USN, CNO, 1957.
The post-WW II era was one of dynamic change. The aircraft carriers reflected that change with many modifications designed to equip them to operate the most modern aircraft capable of delivering nuclear weapons and launching guided missiles.
Technological developments were making the Essex class obsolescent. On 4 June 1947, the Chief of Naval Operations approved new aircraft carrier characteristics to be incorporated in an improvement program titled Project 27A. This was the first of a series of modernisation efforts to modify the Essex carriers to meet changing operating requirements.
USS Oriskany (CV-34) was the first of the Essex class carriers modernised under Project 27A. She entered New York Naval Shipyard in October 1947. At spaced intervals, she was followed by Essex (CV-9), Wasp (CV-18), Kearsarge (CV-33), Lake Champlain (CV-39), Bennington (CV-20), Yorktown (CV-10), Randolph (CV15), and Hornet (CV-12). These programs were conducted at Puget Sound and Newport News, in addition to the New York Navy Yard. The Hornet, last to be modernised under 27A, left the New York yard in October 1953.
The principal changes involved in the 27A project were directed toward a capability of operating aircraft of up to 40,000 pounds gross weight. The H4-1 catapults were removed and H-8s installed, permitting the launching of considerably heavier aircraft than the carrier had been capable of during the war years. The flight decks were strengthened and the five-inch guns on the flight deck were removed to decrease topside weight, to provide more deck space for parking planes, and to increase safety aspects of the landing area. A special weapon capability was given the last six of the nine carriers modernised under this project. Elevator capacities and dimensions were increased to accommodate heavier planes.
USS Essex in her original WW II-era layout.
And special provisions for jet aircraft were installed—such as jet blast deflectors, increased fuel capacity, as well as some modern jet fuel mixers.
Three of the ready rooms for pilots in these carriers were moved down below the hangar deck, relocating them from spaces directly under the flight deck. This increased pilot comfort and provided better protection. To get the equipment-laden pilots up to the flight deck, an escalator was installed abreast the island. This provided a single route for pilots manning their planes; it prevented confusion from ship’s company rushing up the normal access routes to man battle stations.
In April 1947, Franklin D. Roosevelt (FDR) entered the yards on Ship Improvement Program No. 1, which provided her with a special weapon capability. Her sister ships, the battle carriers Midway and Coral Sea, followed. This program was also extended to the Oriskany, Essex and Wasp, which had not received the capability under 27A.
First USN jet deck landing
Almost a year before the FDR entered the yards, the first U.S. testing of the adaptability of jets to shipboard operations were conducted aboard, on July 21, 1946. Successful landings and takeoffs in an FD-1 Phantom were made by LCDR James J. Davidson.
The Deck Landing Mirror, another British invention (left, as fitted in Melbourne), was gyro-stabilised for pitch and adjustable in height and glide path angle for different aircraft. The USN-developed Fresnel Lens (right) was similarly stabilised and gave pilots a similar-looking display, but it was entirely self-contained, requiring no external source lights. The RN (and RAN) dispensed with the Landing Signals Officer with the advent of the Mirror, but the USN retained that person and the RAN later followed the USN.
The Navy continued to experiment with heavier aircraft launchings from carrier decks. In March 1948, carrier suitability of the FJ-1 Fury jet fighters was tested on board the Boxer (CV-21) off San Diego. A number of takeoffs and landings were made by CMDR Evan Aurand and LCDR R. M. Elder of Fighter Squadron 5A. The following month, CMDR T. D. Davis and LCDR J. P. Wheatley made JATO takeoffs in P2V Neptunes from the deck of the Coral Sea off Norfolk. This was the first carrier launching of planes of this size and weight.
Jet squadron CARQUALs
It was inevitable, then, that the Navy would introduce all-jet squadrons to carrier operations. On 5 May 1948, Fighter Squadron 17-A, equipped with 16 FH-1 Phantoms, became the first carrier-qualified jet squadron in the U.S. Navy. It took three days of operations to do it, but all squadron pilots, in addition to Commander Air Group 17, qualified on the USS Saipan (CVL-48), with a minimum of eight landings and takeoffs each.
Project 27A was originally intended for more than nine carriers, but development of the steam catapult and the prospective employment of more advanced types of aircraft made it apparent that this project had to be modified to meet future needs. Accordingly, Project 27C was initiated. Hancock, Intrepid and Ticonderoga were slated for this program—later identified as “Project 27C (axial deck)”.
USS Essex, seen here in Korea in 1951 with McDonnell F2-H Banshees, was the first carrier to operate jet fighters in war. Note the axial deck remains, but the flight-deck level twin five-inch gun turrets, fore and aft of the island, have been removed.
Most important of the changes was the introduction of the steam catapult developed by the British. In 1952, tests of the catapult installed in the Royal Navy carrier HMS Perseus were conducted at the Naval Shipyard, Philadelphia, at NOB Norfolk, and at sea during the first quarter of the year.
HMS Perseus, a Colossus class light fleet carrier, served as an aircraft maintenance and trials ship. In this photograph, Perseus has a Sea Hornet loaded on her prototype steam catapult in late 1951. Between January and March 1952 the ship conducted joint RN and USN steam catapult trials with USN aircraft off Norfolk, VA. Later steam catapults were longer and had faster end-speeds. Others had bridle catchers and there were nose-wheel launch versions. In 2015 an Electromagnetic Aircraft Launch System (EMALS) catapult is projected to be in service with USS Gerald R. Ford (CVN 78), the lead ship in a new class that will also have a smaller island sited well astern on the flight deck abreast the EMALS-engined arrestor units.
The new catapult fared so well during the tests that the Navy has already begun an investigation into the adaptability of it to their new flush deck carrier USS Forrestal, which is now under construction.
The new catapult, invented by a Royal Navy Volunteer Reserve officer, CMDR C. C. Mitchell, OBE, of Messrs Brown Brothers & Co., Ltd., Edinburgh, uses the principle of the slotted cylinder, and has no rams or purchase cables. A hook on the aircraft to be launched is connected directly to a piston which is driven along the cylinder by high pressure steam from the ship’s boilers. A novel sealing device is used to keep the slotted cylinder steam tight.
While the amount of steam required for sustained operation is large, tests have shown that the boilers can meet the demand without interfering with the ship operations.
The Hancock was the first U.S. carrier to receive the new “steam slingshot,” designated C-11 by the USN. On June 1, 1954, CMDR. H. J. Jackson, in a Grumman Tracker S2F-1, was catapulted from the Hancock in the initial U.S. tests. Throughout the operational month, testing continued. A total of 254 launchings were made with S2F Tracker, AD-5 Skyraider, F2H-3 Banshee, F2H-4 Banshee, FJ-2 Fury (modified F-86 Sabre), F7U-3, Cutlass and F3D-2 Skynight aircraft.
USS Hancock CV -19 was the first USN ship to launch an aircraft by a steam catapult (a type C-11). CMDR Henry J. Jackson had the honour, in an S-2 Tracker, 1 June 1954.
In addition to the C-11 steam cat, Project 27C (axial deck) also provided for a strengthening of the flight deck. The number three centerline elevator was replaced with a deck edge type of greater capacity. Other improvements were made, in addition to those proved effcient in 27A. Even as these changes were being built in the Hancock, Intrepid and Ticonderoga, the Bureau of Aeronautics proposed, in mid-June 1952, that a new design flight deck, later embodied in Project 27C (angled deck), be installed in Antietam. The previous May, both jet and propellor type aircraft were tested on a simulated angled deck aboard the USS Midway. The idea was originated by the British and proved very effective. Antietam’s deck was to extend outboard on the port side from the normal flight deck, thus allowing aircraft landings to be angled 10° off the ship’s centerline.
Pushed through the guidance design stage by the Hull Design Branch of BUSHIPS in early July, Antietam’s new deck was completed in mid-December at the New York Naval Shipyard. At first called a canted deck, this term officially gave way to the more familiar angled deck by OPN AV Notice 9020 on 24 February 1955. It also outlawed the use of “slanted” and “slewed” in describing the deck design.
In December 1953, BUSHIPS Journal reported:
The final detailed report on the evaluation of the canted flight deck installed in USS Antietam (CVS-36) reveals that the operational trials have met with a high degree of success. The canted deck aircraft carrier appears to provide the safest, most desirable, and most suitable platform for all types of aircraft—those currently in use as well as those still on the design board—and is superior to the axial flight deck carrier in these respects….The canted flight deck on Antietam was finally installed at an angle of 10.5° to the centerline of the axial flight deck. The landing area of the canted deck is 525 feet long with a width at the landing ramp of 70 feet and narrowing to 32 feet, 8 inches, at the extreme forward end of the takeoff area. This gives the effect of “flying into a funnel,” causing the pilot to head toward the canted centerline. This effect aids him in maintaining the flight and deck path which fully utilizes the complete length of the canted flight deck.
Fifteen types of aircraft, both propellor and jet-propelled, participated in the tests which were conducted in four phases, extending from 29 December 1952 to 1 July 1953. A total of 4107 landings were made, including touch-and-go and arrested landings, during day and night operations. During the entire evaluation period there was no major accident and only a total of eight minor accidents, none of which could be attributed to the canted deck principle.
USS Antietam, conducting the first angled deck landing trials, a joint USN/RN project, in January 1953.
The advantages were immediately manifest. By eliminating the centerline elevators and using one or more deck edge elevators (not installed in the Antietam), more elevators would be available for bringing up spares from the hangar and striking “dud” aircraft below. Once landed, the plane could easily taxi onto a starboard deck edge elevator without impeding flight operations. It was also possible to catapult aircraft and land them simultaneously, and to launch CAP and interceptors on short notice. This gave the carrier improved combat readiness.
The pilots were impressed. An extra margin of safety was given them by removing the danger of crashing into gassed and armed planes parked forward of the landing area.
The BUSHIPS Journal commented:
The clear deck ahead on every carrier pass relieved the pressure on the pilot. Primarily for this reason, pilots who have flown from the canted deck are unanimous in their favorable enthusiasm.
This was found to be especially true when Antietam’s canted deck was rigged to simulate a CVE type carrier. Pilots flying AF type aircraft confirmed that part of the mental strain of carrier landings is relieved with removal of the barriers and that landings were much easier…
Fewer cross deck arresting pendants and arresting gear engines are required for the canted deck. It is considered desirable to keep the landing area as far aft as is practical and safe, yet far enough forward to decrease rates of descent. This can be accomplished only by limiting the pendants to a minimum commensurate with safety and picking optimum pendant locations. Fewer pendants also result in a decrease in topside weight.
Project 27C (angled deck), which resulted from the Antietam tests and modified the original 27A, significantly changed the silhouette of aircraft carriers. The canted or angled deck was installed and the hurricane bow of the original Saratoga and Lexington carriers reintroduced. The project also allowed for the improvement of the Mark 7 arresting gear by reducing the number of deck pendants by one-half and thereby cutting the ratio of arresting gear sheaves to two to one. The forward centerline elevator was also enlarged.
Air conditioning and sound proofing made the island spaces more comfortable and efficient. The latest advancements in deck lighting were also installed in these attack carriers. Lexington, Shangri La, and Bon Homme Richard all received the improvements of this project and they were so successful that Hancock, Intrepid and Ticonderoga returned to the yards for this new conversion.
The trend extended, inevitably, to the Midway class. In September 1953, the Navy announced new modernisation plans for these carriers under a new program called Project 110. In May 1954, the Franklin D. Roosevelt entered Puget Sound Naval Shipyard for the conversion. Midway followed in September 1955.
These carriers received the best features of the 27C (angled deck) conversion which were incorporated in Project 110. Additionally, they had a modified steam catapult installed in the angled deck area; full blisters were added for maximum protection, liquid stowage, and stability, and the after starboard elevator was relocated to the starboard deck edge.
With the changes in carrier configuration ran a parallel change in missions and these changes were reflected in the redesignation of certain carriers as they appeared in the Navy Vessels Register.
On October 1, 1952, the very familiar CV and CVB designations went by the board. The ships were assigned the designation CVA, reflecting their reclassification as attack carriers. Prior to this, only the CVs were known as attack carriers, in the Fleet, to distinguish them from the CVBs. Antisubmarine Support Aircraft Carriers became a new classification in July 1953 and was applied to those attack carriers assigned to ASW; the following August 8, five CVAs were redesignated CVSs, ASW support carriers.
There were no further changes in designations over the next two years, but in July 1955, Thetis Bay (CVE90) became CVHA-1. This proved the first move in the eventual disappearance of escort carriers from the operational Fleet. The attempt to modify CVEs for a new role in helicopter vertical assault operations was abandoned when the experiment proved too costly. On 7 May 1959, the classification of 36 escort carriers, designated CVE, CVU, and CVHE, was changed to AKV, for Cargo Ship and Aircraft Ferry. New hull numbers were assigned. This ended the role of escort carriers as combat ships of the Fleet.
On 30 December 1957, USS Saipan (CVL-48), last of the light carriers, was decommissioned. On May 15, 1959, that designation was stricken from the register when the classification of four support carriers, CVSs, and seven light carriers, CVLs, was changed to Auxiliary Aircraft Transport, AVT.
USS Saipan CVL-48, displacing 14,500 tons, was the first ship of her class commissioned (in July 1946). She was also the last USN CVL to be decommissioned, ten years later. Recommissioned as USS Arlington in January 1970, she served as a major communications and command ship until 1970 and was sold for scrap in 1976.
The modernisation of individual carriers reflected Navy thinking, Navy accomplishment, and Navy planning.
The programs were successive steps in what somebody once called “a schedule of orderly retirement.” As the carriers aged (some aged “faster” because of battle damage in WW II), they were transferred from the CVA designation to the CVS, then to LPH and retirement, and it all was tied to new construction programs which made it possible to keep the number of operating CVAs up to the prescribed limits. As each new ship was acquired, it took the top position among the CVAs while the one in the bottom position moved to the top of the next lower class.
USS Coral Sea (CVA-43) was the last aircraft carrier of World War II design to be extensively reworked during the post-war modernisation program. She entered the Puget Sound shipyard on 15 April 1957, and was recommissioned 25 January 1960. In the interim, changes made in her configuration were contained in Project 110A, a modification of the 110 of her sister ships, FDR and Midway.
Three deck-edge elevators
The basic changes were the same as those in Project 110, but 110A added new features. Of the three deck edge elevators installed, for instance, one was placed on the port side near the LSO platform. This eliminated the hazardous arrangement of having an elevator contiguous to the landing area. It also simplified maintenance problems and provided the capability of operating all three elevators during flight operations.
Existing arresting gear was replaced with five Mk 7-2 pendant and barricade engines with the new sheave and anchor dampers. Coral Sea was the first to have installed, in the fantail area, a complete jet engine test facility; they are now (1963) installed in all new carriers.
Bigger jet fuel stowage
Coral Sea had twice as much stowage for JP-5 (jet) fuel as her sister ships, over a million gallons, in addition to a 62,000 gallon capacity for avgas. And although Ranger was the first to have fuel centrifugal purifiers installed, she did not rely on them exclusively. When Coral Sea deployed to WestPac, she had four of them installed and did use them exclusively. During the first 8½ months of operation, she burned approximately seven million gallons of JP-5, according to Air Officer CMDR. D.W. Houck, and did not experience one case of contaminated jet fuel.
The modernisation program extended the lifetime usefulness of the Essex-class carriers built during WW II and permitted them and other class carriers to operate jet-powered aircraft of increasing designed power without compromising the combat readiness of the Fleet. The important limiting characteristics of the planes operating from carriers are landing speed, landing weight and required catapult end speed, and—in wooden deck ships—the wheel loading.
New arrestor gear
Many new developments have had a profound effect on carrier aviation. In August 1955, for instance, the constant run-out method of controlling arrestment was used in the Mk. 5 arresting gear installed in USS Bennington. Its primary advantage was the ability to arrest a plane with a minimum amount of hook loads. With the earlier pressure types of controls it was necessary to stop the aircraft in a shorter run-out in order to take care of inadvertent overspeed of the aircraft. This put a considerable strain on the planes.
The new system is set for the weight of the landing aircraft. so that a 60,000-pound plane would pull out no more wire than a 10,000-
Other pilot aids include TACAN (Tactical Air Navigation System), which gives pilots bearing and distance from a carrier, the British-developed mirror landing system (improved by the use of Fresnel lenses), and PLAT (Pilot/LSO Landing Aid Television).
ADML Arleigh Burke said in 1957:
We are limited by how far we can go in modernisation programs by the age of the ship.They are getting old. Their machinery is wearing out and they are becoming progressively more expensive to maintain. Like an old car, they must be replaced.
The modernisation programs have been the proving ground for the advances which have been made in carrier operating techniques. But the full combat effectiveness of these developments can be realised only in new construction.
Two years earlier, in 1955, USS Forrestal (CVA-59) was commissioned, the first of a new class aircraft carrier.
USS Forrestal, in 1957, with a mixed propellor-driven and jet air group embarked, possessed all the modern carrier development items. With a noticeably clear deck (below), Forrestal also demonstrated the possiblity of operating a C-130 Hercules.