In many ways, the Korean War started where World War II left off. For the U.S. Navy the big aircraft carriers (CVs) and escort carriers (CVEs) were the same ships that had defeated Japan in 1945. The same could be said of the cruisers, destroyers, minesweepers, and landing craft – even the uniforms and weapons of naval and Marine Corps personnel were unchanged. The same can be said of the Allied nations, particularly the Australians, British, and Canadians. More than that, most of the naval personnel were veterans of the previous war, not only enlisted personnel, but also their commanders, who had held command in various theaters. This gave cohesion to the naval effort, while at the same time commanders were not of an age that might inhibit them from learning the lessons of this unusual conflict.

It is perhaps just as well that neither the North Koreans nor the Chinese had developed techniques for attacking ships at sea, because later trials were to show that the comparatively primitive CICs of the period could not have handled massed air strikes.

But despite the apparent similarity to World War II, Korea was different, and as the fighting progressed, the differences became more obvious. For one thing, the major warships operating off the coast had the benefits of all recent advances in radar and command and control. The creation of combat information centers (CICs) in ships down to destroyer-size (Action Information Organization or AIO in British parlance) late in World War II enabled a warship’s command team to process radar contacts and communications with great rapidity. This was essential, not because of any major air or surface threat from the North Koreans, but to reduce to a minimum “friendly fire” incidents with U.S. or Allied aircraft. It also improved the efficiency of shore bombardment by enabling ships to make prompt responses to calls for gunfire support. It is perhaps just as well that neither the North Koreans nor the Chinese had developed techniques for attacking ships at sea, because later trials were to show that the comparatively primitive CICs of the period could not have handled massed air strikes.

It was the first naval air war fought with jet aircraft, and it soon became obvious that the gain in speed did not come without penalties. Jet fighters and strike aircraft were “gas guzzlers,” with virtually no loiter time over the target. The U.S. Navy also suffered from too great a variety of aircraft types. A doughty veteran like the F4U-4 Corsair acquitted itself well in Korea with the Marines because of its formidable firepower, and outlasted the more modern F8F-1 Bearcat. Similarly the AD-1 Skyraider was to continue in service until after the Vietnam War because of its usefulness. But jet aircraft promised so much more speed that a number of day fighter types were approved for development in 1945: the McDonnell FH-1 Phantom, the F2H Banshee, the Chance Vought F6U-1, and North American FJ-1 Fury. All were no more than faster equivalents of contemporary piston-engined fighters, and that speed was bought at a price. Early jet engines produced relatively low thrust in proportion to aircraft weight, making the aircraft accelerate sluggishly; the only cure was a longer flight deck or catapult-assisted takeoff. It also made for difficult landings, and high stall speeds imposed strains on arresting gear and catapults.

Range was the biggest headache. When the Banshee entered service in 1949 it required a total of 16,160 pounds of fuel (877 U.S. gallons) to achieve a combat radius of 480 nautical miles at an average speed of 426 knots. By comparison, the piston-engined Hellcat needed only 2,400 pounds (400 U.S. gallons) to achieve a combat radius of 340 nautical miles at 173 knots. Although superficially an impressive performance for a jet fighter, this meant that a carrier with a gasoline capacity of 200,000 gallons could support only 228 Banshee flights, as against 500 Hellcat flights.

Whatever the drawbacks of these pioneer jet aircraft, they proved a match for North Korean and Chinese aircraft. The MiG-15 caused near panic when it appeared, because of its high speed, but the pilots lacked the tactical skills and experience of their opponents.

At the outbreak of war in 1950, three types of jet fighters were in service: the FJ-1 Fury, F2H Banshee, and F9F Panther.

Of these, the Panther was withdrawn in 1958 and the Fury was withdrawn in 1959, although an improved swept-wing variant of the Panther, the F-9F Cougar, lasted until 1960, and a much improved Fury, the FJ-4, lasted until 1962. Whatever the drawbacks of these pioneer jet aircraft, they proved a match for North Korean and Chinese aircraft. The MiG-15 caused near panic when it appeared, because of its high speed, but the pilots lacked the tactical skills and experience of their opponents.

These drawbacks had little effect on the overall efficiency of carrier operations in Korea. In practice the enormous contribution made by the Essex-class carriers in particular went far to vindicate the U.S. Navy’s fight to make the carriers its main strike weapon. The Navy’s first postwar carrier, the 65,000-ton United States (CVB 58) had been suspended shortly after the laying of her keel in 1949, and then canceled to release funds for the Air Force’s B-36 bomber program. The fight had been a bitter one, with the Air Force working very hard to convince the Truman administration that carriers were too vulnerable for modern warfare. Korea provided the excuse to reverse the verdict, and in 1952 work started on the construction of the first of a new class of “super carriers,” the 60,000-ton USS Forrestal. She and her sister ships were to become the linchpin of the U.S. Navy’s surface strike forces. So successful was the concept that it remains the basis of today’s nuclear-powered carriers (CVNs).

The Korean experience also expedited the program to modernize the Essex-class carriers. The suspended Oriskany (CV 34) was completed to a revised design in 1950, while the Essex (CV 9) and Wasp (CV 18) started their rebuilding to the same SCB-27A design in September 1948 and were completed in February and September 1951 respectively. The upgrades included catapults capable of launching 20-ton aircraft, a strengthened flight deck in the landing area, removal of the twin 5-inch guns, larger and more powerful elevators, installations to facilitate handling of jet aircraft, and providing a more compact but taller “island” superstructure. Three more followed in 1950, and another three in 1951. Other carriers of the class underwent a similar but more advanced conversion from 1951 onwards.

The Korean experience also expedited the program to modernize the Essex-class carriers. The suspended Oriskany (CV 34) was completed to a revised design in 1950, while the Essex (CV 9) and Wasp (CV 18) started their rebuilding to the same SCB-27A design in September 1948 and were completed in February and September 1951 respectively. The upgrades included catapults capable of launching 20-ton aircraft, a strengthened flight deck in the landing area, removal of the twin 5-inch guns, larger and more powerful elevators, installations to facilitate handling of jet aircraft, and providing a more compact but taller “island” superstructure.

Although the aircraft used in Korea served with distinction, it was clear that the U.S. Navy needed a new generation of carrier aircraft, and these were delivered in good time for the Vietnam War. The best of these were the F-8 Crusader, the F-4 Phantom, the A-4 Skyhawk, and the A-6 Intruder. The British also realized the shortcomings of their Fleet Air Arm, and their close cooperation with the U.S. Navy in Korea led to great improvements in operational efficiency. When all the lessons of Korea had been absorbed, the Royal Navy was able to play a much more useful role in NATO.

The emphasis on air-to-ground attack led to a new generation of weapons. A whole series of free-fall bombs was developed in the late 1950s, starting with Snakeye, a standard Mk. 81 or Mk. 82 fitted with fin retarders to allow the weapon to be carried at high speed and dropped at low altitude without destroying the bomber. Rockeye (Mk. 12) was an anti-armor weapon containing 96 bomblets, but before it entered production it was superseded by Rockeye II (Mk. 20), which did not enter service until the mid-1960s. In response to requirements from Korea, the China Lake Weapons Test Center produced the 6.5-inch ATAR anti-tank rocket in only 23 days! ATAR had a shaped charge warhead capable of penetrating 17 inches of armor. About the same time China Lake developed a 2.75-inch Folding Fin Aircraft Rocket (FFAR), primarily intended as an air-to-air weapon against bombers. Known as “Mighty Mouse,” it was also used as a ground attack weapon. Zuni was a 5-inch weapon designed for both air-to-air and air-to-ground attack, and like Mighty Mouse it was destined to remain in service for many years.