Though aircraft carriers are given their definition with respect to fixed-wing aircraft, the first known instance of using a ship for airborne operations occurred in 1806, when the British Royal Navy's Lord Thomas Cochrane launched kites from the 32-gun frigate HMS Pallas in order to drop propaganda leaflets on the French territory.
Balloon carriers
On July 12, 1849, the Austrian Navy ship Vulcano launched a manned hot air balloon in order to drop bombs on Venice, although the attempt failed due to contrary winds.
Later, during the American Civil War, about the time of the Peninsula Campaign, gas-filled balloons were being used to perform reconnaissance on Confederate positions. The battles soon turned inland into the heavily forested areas of the Peninsula, however, where balloons could not travel. A coal barge, the George Washington Parke Custis, was cleared of all deck rigging to accommodate the gas generators and apparatus of balloons. From the GWP Prof. Thaddeus S. C. Lowe, Chief Aeronaut of the Union Army Balloon Corps, made his first ascents over the Potomac River and telegraphed claims of the success of the first aerial venture ever made from a water-borne vessel. Other barges were converted to assist with the other military balloons transported about the eastern waterways. It is only fair to point out in deference to modern aircraft carriers that none of these Civil War crafts had ever taken to the high seas.
Balloons launched from ships led to the development of balloon carriers, or balloon tenders, during World War I, by the navies of Great Britain, France, Germany, Italy, Russia, and Sweden. About ten such "balloon tenders" were built, their main objective being aerial observation posts. These ships were either decommissioned or converted to seaplane tenders after the war.
Seaplane carriers
The invention of the seaplane in March 1910 with the French Le Canard led to the earliest development of a ship designed to carry airplanes, albeit equipped with floats: in December 1911 appears the French Navy La Foudre, the first seaplane carrier, and the first known carrier of airplanes. Commissioned as a seaplane tender, and carrying float-equipped planes under hangars on the main deck, from where they were lowered on the sea with a crane, she participated in tactical exercises in the Mediterranean in 1912. La Foudre was further modified in November 1913 with a 10 meter long flat deck to launch her seaplanes.
HMS Hermes, temporarily converted as an experimental seaplane carrier in April-May 1913, is also one of the first seaplane carriers, and the first experimental seaplane carrier of the British Navy. She was originally laid down as a merchant ship, but was converted on the building stocks to be a seaplane carrier for a few trials in 1913, before being converted again to a cruiser, and back again to a seaplane carrier in 1914. She was sunk by a German submarine in October 1914. The first seaplane tender of the US Navy was the USS Mississippi, converted to that role in December 1913.
Many cruisers and capital ships of the inter-war years often carried a catapult launched seaplane for reconnaissance and spotting the fall of the guns. It was launched by a catapult and recovered by crane from the water after landing. These were highly successful during World War II; there were many notable successes early in the war as shown by HMS Warspite’s float equipped Swordfish during operations in the Norwegian fjords in 1940. The Japanese Rufe floatplane derived from the Zero was a formidable fighter with only a slight loss in flight performance, one of their pilots scored 26 kills in the A6M2-N Rufe; a score only bettered by a handful of American pilots throughout WW2. Other Japanese seaplanes launched from tenders and warships sank merchant ships and small-scale ground attacks. The culmination of the type was the American 300+ mph (480 km/h) Curtiss SC Seahawk which was actually a fighter aircraft like the Rufe in addition to a two-seat gunnery spotter and transport for an injured man in a litter. Spotter seaplane aircraft on U.S. Navy cruisers and battleships were in service until 1949. Seaplane fighters were considered poor combat aircraft compared to their carrier-launched brethren; they were slower due to the drag of their pontoons or boat hulls. Contemporary propeller-driven, land-based fighter aircraft were much faster (450-480 mph / 720-770 km/h as opposed to 300-350 mph / 480-560 km/h) and more heavily armed. The Curtiss Seahawk only had two 0.50 inch (12.7 mm) calibre machine guns compared to four 20 mm cannon in the Grumman F8F Bearcat or four 0.50 (12.7 mm) cal machine guns plus two 20 mm cannon in the Vought F4U Corsair. Jet aircraft of just a few years later were faster still (500+ mph) and still better armed, especially with the development of air to air missiles in the early to mid 1950s.
Genesis of the flat-deck carrier
| "An airplane-carrying vessel is indispensable. These vessels will be constructed on a plan very different from what is currently used. First of all the deck will be cleared of all obstacles. It will be flat, as wide as possible without jeopardizing the nautical lines of the hull, and it will look like a landing field." |
| Clément Ader, "L'Aviation Militaire", 1909 |
As heavier-than-air aircraft developed in the early 20th century various navies began to take an interest in their potential use as scouts for their big gun warships. In 1909 the French inventor Clément Ader published in his book "L'Aviation Militaire" the description of a ship to operate airplanes at sea, with a flat flight deck, an island superstructure, deck elevators and a hangar bay. That year the US Naval Attaché in Paris sent a report on his observations.
A number of experimental flights were made to test the concept. Eugene Ely was the first pilot to launch from a stationary ship in November 1910. He took off from a structure fixed over the forecastle of the US armored cruiser USS Birmingham at Hampton Roads, Virginia and landed nearby on Willoughby Spit after some five minutes in the air.
On January 18, 1911 he became the first pilot to land on a stationary ship. He took off from the Tanforan racetrack and landed on a similar temporary structure on the aft of USS Pennsylvania anchored at the San Francisco waterfront — the improvised braking system of sandbags and ropes led directly to the arrestor hook and wires described above. His aircraft was then turned around and he was able to take off again. Commander Charles Samson, RN, became the first airman to take off from a moving warship on May 2, 1912. He took off in a Short S27 from the battleship HMS Hibernia while she steamed at 10.5 knots (19 km/h) during the Royal Fleet Review at Weymouth.
World War I
The first strike from a carrier against a land target as well as a sea target took place in September 1914 when the Imperial Japanese Navy seaplane carrier Wakamiya conducted the world's first naval-launched air raids from Kiaochow Bay during the Battle of Tsingtao in China. The four Maurice Farman seaplanes bombarded German-held land targets (communication centers and command centers) and damaged a German minelayer in the Tsingtao peninsula from September until November 6, 1914, when the Germans surrendered. On the Western front the first naval air raid occurred on December 25, 1914 when twelve seaplanes from HMS Engadine, Riviera and Empress (cross-channel steamers converted into seaplane carriers) attacked the Zeppelin base at Cuxhaven. The attack was not a complete success, although a German warship was damaged; nevertheless the raid demonstrated in the European theatre the feasibility of attack by ship-borne aircraft and showed the strategic importance of this new weapon.
HMS Ark Royal was arguably the first modern aircraft carrier. She was originally laid down as a merchant ship, but was converted on the building stocks to be a hybrid airplane/seaplane carrier with a launch platform. Launched September 5, 1914, she served in the Dardanelles campaign and throughout World War I.
Other carrier operations were mounted during the war the most successful taking place on 19 July 1918 when seven Sopwith Camels launched from HMS Furious attacked the German Zeppelin base at Tondern, with two 50 lb (23 kg) bombs each. Several airships and balloons were destroyed, but as the carrier had no method of recovering the aircraft safely, two of the pilots ditched their aircraft in the sea alongside the carrier while the others headed for neutral Denmark.
Inter-war years
The Washington Naval Treaty of 1922 placed strict limits on the tonnages of battleships and battlecruisers for the major naval powers after World War I, as well as limits not only on the total tonnage for carriers, but also an upper limit on 27,000 tonnes for each ship. Although exceptions were made regarding the max ship tonnage (fleet units counted, experimental units did not), the total tonnage could not be exceeded. However, while all of the major navies were over-tonnage on battleships, they were all considerably under-tonnage on aircraft carriers. Consequently, many battleships and battlecruisers under construction (or in service) were converted into aircraft carriers. The first ship to have a full length flat deck was HMS Argus the conversion of which was completed in September 1918, with the U.S. Navy not following suit until 1920, when the conversion of USS Langley (an experimental ship which did not count against America's carrier tonnage) had completed. The first American fleet carriers would not join the service until 1928 (USS Lexington and Saratoga).
The first purpose-designed aircraft carrier to be developed was the HMS Hermes, although the first one to be commissioned was the Japanese Hōshō (commissioned in December 1922, followed by HMS Hermes in July 1923).Hermes' design preceded and influenced that of Hōshō, and its construction actually began earlier, but numerous tests, experiments and budget considerations delayed its commission.
By the late 1930s, aircraft carriers around the world typically carried three types of aircraft: torpedo bombers, also used for conventional bombings and reconnaissance; dive bombers, also used for reconnaissance (in the U.S. Navy, this type of aircraft were known as "scout bombers"); and fighters for fleet defence and bomber escort duties. Because of the restricted space on aircraft carriers, all these aircraft were of small, single-engined types, usually with folding wings to facilitate storage.
World War II
Aircraft carriers played a significant role in World War II. With seven aircraft carriers afloat, the British Royal Navy had a considerable numerical advantage at the start of the war as neither the Germans nor the Italians had carriers of their own. However, the vulnerability of carriers compared to traditional battleships when forced into a gun-range encounter was quickly illustrated by the sinking of HMS Glorious by German battlecruisers during the Norwegian campaign in 1940.
This apparent weakness to battleships was turned on its head in November 1940 when HMS Illustrious launched a long-range strike on the Italian fleet at Taranto. This operation incapacitated three of the six battleships in the harbour at a cost of two of the 21 attacking Fairey Swordfish torpedo bombers. Carriers also played a major part in reinforcing Malta, both by transporting planes and by defending convoys sent to supply the besieged island. The use of carriers prevented the Italian Navy and land-based German aircraft from dominating the Mediterranean theatre.
In the Atlantic, aircraft from HMS Ark Royal and HMS Victorious were responsible for slowing Bismarck during May 1941. Later in the war, escort carriers proved their worth guarding convoys crossing the Atlantic and Arctic oceans.
Many of the major battles in the Pacific involved aircraft carriers. Japan started the war with ten aircraft carriers, the largest and most modern carrier fleet in the world at that time. There were six American aircraft carriers at the beginning of the hostilities, although only three of them were operating in the Pacific.
Drawing on the 1939 Japanese development of shallow water modifications for aerial torpedoes and the 1940 British aerial attack on the Italian fleet at Taranto, the 1941 Japanese surprise attack on Pearl Harbor was a clear illustration of the power projection capability afforded by a large force of modern carriers. Concentrating six flattops in a single striking unit marked a turning point in naval history, as no other nation had fielded anything comparable. (Though Germany and Italy began construction of carriers, neither were completed. Of the two, Germany's Graf Zeppelin had the greater potential.)
Meanwhile, the Japanese began their advance through Southeast Asia and the sinking of Prince of Wales and Repulse by Japanese land-based aircraft drove home the need for this ship class for fleet defence from aerial attack. In April 1942, the Japanese fast carrier strike force ranged into the Indian Ocean and sank shipping, including the damaged and undefended carrier HMS Hermes. Smaller Allied fleets with inadequate aerial protection were forced to retreat or be destroyed. In the Coral Sea, US and Japanese fleets traded aircraft strikes in the first battle where neither side's ships sighted the other. At the Battle of Midway all four Japanese carriers engaged were sunk by planes from three American carriers (one of which was lost) and the battle is considered the turning point of the war in the Pacific. Notably, the battle was orchestrated by the Japanese to draw out American carriers that had proven very elusive and troublesome to the Japanese.
Subsequently the US was able to build up large numbers of aircraft aboard a mixture of fleet, light and (newly commissioned) escort carriers, primarily with the introduction of the Essex class in 1943. These ships, around which were built the fast carrier task forces of the Third and Fifth Fleets, played a major part in winning the Pacific war. The eclipse of the battleship as the primary component of a fleet was clearly illustrated by the sinking of the largest battleship ever built, Yamato, by carrier-borne aircraft in 1945. Japan also built the largest aircraft carrier of the war, Shinano, which was a Yamato class ship converted mid-way through construction after the disastrous loss of four fleet carriers at Midway. She was sunk by a patrolling US submarine while in transit shortly after commissioning, but before being fully outfitted or operational in November 1944.
Important innovations just before and during World War II
Hurricane bow
A hurricane bow is a completely enclosed hangar deck, first seen on the American Lexington class aircraft carriers which entered service in 1927. Combat experience proved it to be by far the most useful configuration for the bow of the ship among others that were tried; including second flying-off decks and an anti-aircraft battery (the latter was the most common American configuration during World War II). This feature would be re-incorporated into American carriers post-war. The Japanese carrier Taihō was the first of their ships to incorporate it.
Light aircraft carriers
The loss of three major carriers in quick succession in the Pacific led the US Navy to develop the light carrier (CVL) from light cruiser hulls that had already been laid down. They were intended to provide additional fast carriers, as escort carriers did not have the requisite speed to keep up with the fleet carriers and their escorts. The actual U.S. Navy classification was small aircraft carrier (CVL), not light. Prior to July 1943, they were just classified as aircraft carriers (CV).
The British Royal Navy made a similar design which served both them and Commonwealth countries after World War II. One of these carriers, India's INS Viraat, formerly HMS Hermes, is still being used.
Escort carriers and merchant aircraft carriers
To protect Atlantic convoys, the British developed what they called Merchant Aircraft Carriers, which were merchant ships equipped with a flat deck for half a dozen aircraft. These operated with civilian crews, under merchant colors, and carried their normal cargo besides providing air support for the convoy. As there was no lift or hangar, aircraft maintenance was limited and the aircraft spent the entire trip sitting on the deck.
These served as stop-gap until dedicated escort carriers could be built in the US (US classification CVE). About a third of the size of a fleet carrier, it carried about two dozen aircraft for anti-submarine duties. Over one hundred were built or converted from merchantmen.
Escort carriers were built in the US from two basic hull designs: one from a merchant ship, and the other from a slightly larger, slightly faster tanker. Besides defending convoys, these were used to transport aircraft across the ocean. Nevertheless, some participated in the battles to liberate the Philippines, notably the Battle off Samar in which six escort carriers and their escorting destroyers briefly took on five Japanese battleships and bluffed them into retreating.
Catapult aircraft merchantmen
As an emergency stop-gap before sufficient merchant aircraft carriers became available, the British provided air cover for convoys using Catapult aircraft merchantman (CAM ships) and merchant aircraft carriers. CAM ships were merchant vessels equipped with an aircraft, usually a battle-weary Hawker Hurricane, launched by a catapult. Once launched, the aircraft could not land back on the deck and had to ditch in the sea if it was not within range of land. Over two years, fewer than 10 launches were ever made, yet these flights did have some success: 6 bombers for the loss of a single pilot.
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