Japanese cruiser Asama
Asama was the lead ship of her class of armored cruisers built for the Imperial Japanese Navy in the late 1890s. As Japan lacked the industrial capacity to build such warships herself, the ship was built in Britain, she served in the Russo-Japanese War of 1904–05 during which she participated in the Battle of Chemulpo Bay and the Battle of the Yellow Sea without damage, although her luck did not hold out during the Battle of Tsushima. Early in World War I, Asama unsuccessfully searched for German commerce raiders until she was damaged when she ran aground off the Mexican coast in early 1915. Repairs took over two years to complete and she was used as a training ship for the rest of her career; the ship made a total of 12 training cruises before she was crippled after running aground again in 1935. Asama became a stationary training ship until she was broken up in 1946–47; the 1896 Naval Expansion Plan was made after the First Sino-Japanese War and included four armored cruisers in addition to four more battleships, all of which had to be ordered from British shipyards as Japan lacked the capability to build them itself.
Further consideration of the Russian building program caused the IJN to believe that the battleships ordered under the original plan would not be sufficient to counter the Imperial Russian Navy. Budgetary limitations prevented ordering more battleships and the IJN decided to expand the number of more affordable armored cruisers to be ordered from four to six ships; the revised plan is known as the "Six-Six Fleet". Unlike most of their contemporaries which were designed for commerce raiding or to defend colonies and trade routes and her half-sisters were intended as fleet scouts and to be employed in the battleline; the ship was 134.72 meters long overall and 124.36 meters between perpendiculars. She had a beam of 20.48 meters and had an average draft of 7.43 meters. Asama displaced 9,710 metric tons at normal load and 10,519 metric tons at deep load; the ship had a metacentric height of 0.85 meters. Her crew consisted of 676 officers and enlisted men. Asama had two 4-cylinder triple-expansion steam engines, each driving a single propeller shaft.
Steam for the engines was provided by a dozen cylindrical boilers and the engines were rated at a total of 18,000 indicated horsepower. The ship had a designed speed of 22 knots and reached 22.07 knots during her sea trials from 19,000 ihp. She carried up to 1,390 long tons of coal and could steam for 10,000 nautical miles at a speed of 10 knots; the main armament for all of the "Six-Six Fleet" armored cruisers was four eight-inch guns in twin-gun turrets fore and aft of the superstructure. The secondary armament consisted of 14 Elswick Ordnance Company "Pattern Z" quick-firing, 6-inch guns. Only four of these guns were not mounted in armored casemates on the main and upper decks and their mounts on the upper deck were protected by gun shields. Asama was equipped with a dozen QF 12-pounder 12-cwt guns and eight QF 2.5-pounder Yamauchi guns as close-range defense against torpedo boats. The ship was equipped with five 457 mm torpedo tubes, one above water in the bow and four submerged tubes, two on each broadside.
All of the "Six-Six Fleet" armored cruisers used the same armor scheme with some minor differences, of which the most important was that the two Asama-class ships used less tough Harvey armor. The waterline belt ran the full length of the ship and its thickness varied from 178 millimeters amidships to 89 millimeters at the bow and stern, it had a height of 2.13 meters, of which 1.52 meters was underwater. The upper strake of belt armor was 127 millimeters thick and extended from the upper edge of the waterline belt to the main deck, it extended 65.42 meters from the forward to the rear barbette. The Asama class had oblique 127 mm armored bulkheads that closed off the ends of the central armored citadel; the barbettes, gun turrets and the front of the casemates were all 152-millimeters thick while the sides and rear of the casemates were protected by 51 millimeters of armor. The deck was 51-millimeters thick and the armor protecting the conning tower was 356 millimeters in thickness; the contract for Asama, named after Mount Asama, was signed on 6 July 1897 with Armstrong Whitworth.
The ship had been laid down at their shipyard in Elswick on 20 October 1896 as a speculative venture. She was launched on 21 March 1898 and completed on 18 March 1899. Asama left for Japan the next day and arrived in Yokosuka on 17 May. On 30 April 1900, the ship was used by Emperor Meiji during a fleet review off at Kobe. In July 1902, Asama was the flagship of Rear-Admiral G. Ijuin as part of the delegation dispatched to the United Kingdom for the Coronation Review for King Edward VII in Spithead on 16 August, she visited Antwerp in July, Cork in August. During the outward leg of this voyage, the ship tested some advanced British radio technology between Malta and Britain. At the beginning of the Russo-Japanese War in February 1904, Asama was assigned to the 2nd Division of the 2nd Fleet, although she was attached to the 4th Division of Rear Admiral Uryū Sotokichi for operations near Seoul, Korea, his ships were tasked to escort transports carrying troops to Chemulpo, Seoul's port on the west coast, to destroy the Russian protected cruiser Varyag and gunboat Korietz stationed in Chemulpo as guardships.
The troops were unloaded during the night of 8/9 February and the Japanese ships left the harbor the following morning to assume po
The escort carrier or escort aircraft carrier called a "jeep carrier" or "baby flattop" in the United States Navy or "Woolworth Carrier" by the Royal Navy, was a small and slow type of aircraft carrier used by the Royal Navy, the United States Navy, the Imperial Japanese Navy and Imperial Japanese Army Air Force in World War II. They were half the length and a third the displacement of larger fleet carriers. While they were slower, carried fewer planes and were less well armed and armored, escort carriers were cheaper and could be built, their principal advantage. Escort carriers could be completed in greater numbers as a stop-gap. However, the lack of protection made escort carriers vulnerable and several were sunk with great loss of life; the light carrier was a similar concept to escort carriers in most respects, but were capable of higher speeds to allow operation alongside fleet carriers. Most built on a commercial ship hull, escort carriers were too slow to keep up with the main forces consisting of fleet carriers and cruisers.
Instead, they were used to escort convoys, defending them from enemy threats such as submarines and planes. In the invasions of mainland Europe and Pacific islands, escort carriers provided air support to ground forces during amphibious operations. Escort carriers served as backup aircraft transports for fleet carriers and ferried aircraft of all military services to points of delivery. In the Battle of the Atlantic, escort carriers were used to protect convoys against U-boats. Escort carriers accompanied the merchant ships and helped to fend off attacks from aircraft and submarines; as numbers increased in the war, escort carriers formed part of hunter-killer groups that sought out submarines instead of being attached to a particular convoy. In the Pacific theater, CVEs provided air support of ground troops in the Battle of Leyte Gulf, they lacked the speed and weapons to counter enemy fleets, relying on the protection of a Fast Carrier Task Force. However, at the Battle off Samar, one U. S. task force of escort carriers managed to defend itself against a much larger Japanese force of battleships and cruisers.
The Japanese met a furious defense of carrier aircraft, screening destroyers, destroyer escorts, proving that CVEs could appear to have the same striking power as full CVs. Of the 151 aircraft carriers built in the U. S. during World War II, 122 were escort carriers. Though no examples survive to this day, the Casablanca class was the most numerous class of aircraft carrier, with 50 launched. Second was the Bogue class, with 45 launched. In the early 1920s, the Washington Naval Treaty imposed limits on the maximum size and total tonnage of aircraft carriers for the five main naval powers. Treaties kept these provisions; as a result, construction between the World Wars had been insufficient to meet operational needs for aircraft carriers as World War II expanded from Europe. Too few fleet carriers were available to transport aircraft to distant bases, support amphibious invasions, offer carrier landing training for replacement pilots, conduct anti-submarine patrols, provide defensive air cover for deployed battleships and cruisers.
The foregoing mission requirements limited use of fleet carriers′ unique offensive strike capability demonstrated at the Battle of Taranto and the Attack on Pearl Harbor. Conversion of existing ships provided additional aircraft carriers until new construction became available. Conversions of cruisers and passenger liners with speed similar to fleet carriers were identified by the U. S. as "light aircraft carriers" able to operate at battle fleet speeds. Slower conversions were classified as "escort carriers" and were considered naval auxiliaries suitable for pilot training and transport of aircraft to distant bases; the Royal Navy had recognized a need for carriers to defend its trade routes in the 1930s. While designs had been prepared for "trade protection carriers" and five suitable liners identified for conversion, nothing further was done because there were insufficient aircraft for the fleet carriers under construction at the time. However, by 1940 the need had become urgent and HMS Audacity was converted from the captured German merchant ship MV Hannover and commissioned in July 1941.
For defense from German aircraft, convoys were supplied first with fighter catapult ships and CAM ships that could carry a single fighter. In the interim, before escort carriers could be supplied, they brought in merchant aircraft carriers that could operate four aircraft. In 1940, Admiral William Halsey recommended construction of naval auxiliaries for pilot training. In early 1941 the British asked the US to build on their behalf six carriers of an improved Audacity design but the US had begun their own escort carrier. On 1 February 1941, the United States Chief of Naval Operations gave priority to construction of naval auxiliaries for aircraft transport. U. S. ships built to meet these needs were referred to as auxiliary aircraft escort vessels in February 1942 and auxiliary aircraft carrier on 5 August 1942. The first U. S. example of the type was USS Long Island. Operation Torch and North Atlantic anti-submarine warfare proved these ships capable aircraft carriers for ship formations moving at the speed of trade or amphibious invasion convoys.
U. S. classification revision to escort aircraft carrier on 15 July 1943 reflected upgraded status from auxiliary to combatant. They were informally known as "Jeep carriers" or "baby flattops", it was
Unryū-class aircraft carrier
The Unryū-class aircraft carriers were World War II Japanese aircraft carriers. 16 carriers were planned under the Kai-Maru 5 Programme. However, only three of the Unryū-class carriers were completed. In the lead-up to the Pacific War the Imperial Japanese Navy attempted to build a large number of fleet carriers. For them to be built the design for these ships was based on the aircraft carrier Hiryū rather than the newer and more sophisticated Taihō or the Shōkaku class; the Unryū-class aircraft carrier design was similar to that of Hiryū. The ships were built, the main difference from Hiryū was that the carriers' island was placed on the starboard side of the ships; the carriers were capable of carrying 63 aircraft in two hangars, were fitted with two elevators. The Unryū class carried a smaller quantity of aviation fuel than Hiryū with fuel tanks protected by concrete; the ships were fitted with the same propulsion system used in the aircraft carrier Sōryū to reach 34 knots, though Katsuragi was instead fitted with two turbines of the same type used in destroyers and had a maximum speed of 32 knots.
The carriers had a similar armament as Hiryū and were equipped with two Type 21 radars and two Type 13 radars. The first three Unryū-class aircraft carriers were laid down in 1942 and construction of a further three began the next year. Only three were completed and construction of the other three carriers was abandoned in 1945. Project number was G16. General production model of the Unryū class. 3 carriers were completed. The IJN unofficial designation for Unryū and Amagi were Modified Hiryū class, Ship Number 5002–5006 were Modified Unryū class also. Amagi and Kasagi were equipped with surplus stock of the Ibuki-class cruiser machinery. Katsuragi and Aso were equipped with two sets of the Kagerō-class destroyer machinery, because Japanese industry power became scarce. Dead space was replaced by fuel tanks. Ship Number 5002 and 5005 were to have been built using Shinano's dock. However, they were cancelled. Simplified and sped-up construction model of the Unryū class, they fitted shift-arrangement machinery.
Therefore, as for their chimneys/funnels/smokepipes/uptakes, those were intended to be spaced out. The IJN unofficial designation for this class was Modified Ship Number 302-class. List of ships of the Second World War List of ship classes of the Second World War "Unryu class". Combinedfleet.com. Retrieved 2008-02-05. Lengerer, Hans. Illustrated Record of the Transition of the Superstructures of BB Kongô Class: Introduction to CV Unryû Class. Katowice, Poland: Model Hobby. ISBN 978-83-60041-42-0. Stille, Mark. Imperial Japanese Navy Aircraft Carriers, 1921 - 45. New Vanguard. Oxford: Osprey. ISBN 1-84176-853-7. Worth, Richard. Fleets of World War II. Da Capo Press. ISBN 0-306-81116-2. Shizuo Fukui, "Stories of Japanese aircraft carriers", Kōjinsha August 1996, ISBN 4-7698-0655-8 "Rekishi Gunzō". History of Pacific War Extra, "Perfect guide, The aircraft carriers of the Imperial Japanese Navy & Army", April 2003, ISBN 4-05-603055-3 Daiji Katagiri, Ship Name Chronicles of the Imperial Japanese Navy Combined Fleet, Kōjinsha, June 1988, ISBN 4-7698-0386-9 "Japan Center for Asian Historical Records".
National Archives of Japan, "List of main points and features of surface vessels under construction", Reference code: A03032074600 Monthly Ships of the World, "Kaijinsha". No. 481, Special issue, "History of Japanese Aircraft Carriers", May 1994 No. 736, Special issue, "History of Japanese Aircraft Carriers", January 2011 The Maru Special, Ushio Shobo Warship Mechanism Vol. 3, "Mechanisms of Japanese 29 Aircraft Carriers", August 1981 Japanese Naval Vessels No. 23, "Japanese aircraft carriers I", January 1979 Senshi Sōsho, Asagumo Simbun Vol. 31, Naval armaments and war preparation, "Until November 1941", November 1969 Vol. 88, Naval armaments and war preparation, "And after the outbreak of war", October 1975 Andrew Toppan. "World Aircraft Carriers List: Japanese Aircraft Carriers". Hazegray.org. Retrieved 2008-02-05
Japanese aircraft carrier Hiryū
Hiryū was an aircraft carrier built for the Imperial Japanese Navy during the 1930s. The only ship of her class, she was built to a modified Sōryū design, her aircraft supported the Japanese invasion of French Indochina in mid-1940. During the first month of the Pacific War, she took part in the attack on Pearl Harbor and the Battle of Wake Island; the ship supported the conquest of the Dutch East Indies in January 1942. The following month, her aircraft bombed Darwin and continued to assist in the Dutch East Indies campaign. In April, Hiryū's aircraft helped sink two British heavy cruisers and several merchant ships during the Indian Ocean raid. After a brief refit, Hiryū and three other fleet carriers of the First Air Fleet participated in the Battle of Midway in June 1942. After bombarding American forces on the atoll, the carriers were attacked by aircraft from Midway and the carriers USS Enterprise and Yorktown. Dive bombers from Yorktown and Enterprise set her afire, she was scuttled the following day.
The loss of Hiryū and three other IJN carriers at Midway was a crucial strategic defeat for Japan and contributed to the Allies' ultimate victory in the Pacific. Hiryū was one of two large carriers approved for construction under the 1931–32 Supplementary Program. Designed as the sister ship of Sōryū, her design was enlarged and modified in light of the Tomozuru and Fourth Fleet Incidents in 1934–35 that revealed many IJN ships were top-heavy and structurally weak, her forecastle was raised and her hull strengthened. Other changes involved increasing her beam and armor protection; the ship had a length of a beam of 22.3 meters and a draft of 7.8 meters. She displaced 17,600 metric tons at 20,570 metric tons at normal load, her crew enlisted men. Hiryū was fitted with four geared steam turbine sets with a total of 153,000 shaft horsepower, each driving one propeller shaft, using steam provided by eight Kampon water-tube boilers; the turbines and boilers were the same as those used in the Mogami-class cruisers.
The ship's power and slim, cruiser-type hull with a length-to-beam ratio of 10:1 gave her a speed of 34.3 knots and made her the fastest carrier in the world at the time of her commissioning. Hiryū carried 4,500 metric tons of fuel oil which gave her a range of 10,330 nautical miles at 18 knots; the boiler uptakes were trunked to the ship's starboard side amidships and exhausted just below flight deck level through two funnels curved downward. The carrier's 216.9-meter flight deck was 27.0 meters wide and overhung her superstructure at both ends, supported by pairs of pillars. Hiryū was one of only two carriers built whose island was on the port side of the ship, it was positioned further to the rear and encroached on the width of the flight deck, unlike Sōryū. Nine transverse arrestor wires were installed on the flight deck that could stop a 6,000-kilogram aircraft. One group of three wires was positioned further forward to allow the ship to land aircraft over the bow, although this was never done in practice.
The flight deck was only 12.8 meters above the waterline and the ship's designers kept this figure low by reducing the height of the hangars. The upper hangar had an approximate height of 4.6 meters. Together they had an approximate total area of 5,736 square meters; this caused problems in handling aircraft because the wings of a Nakajima B5N "Kate" torpedo bomber could neither be spread nor folded in the upper hangar. Aircraft were transported between the hangars and the flight deck by three elevators, the forward one abreast the island on the centerline and the other two offset to starboard; the forward platform measured 16.0 by 13.0 meters, the middle one 13.0 by 12.0 meters, the rear 11.8 by 13.0 meters. They were capable of transferring aircraft weighing up to 5,000 kilograms. Hiryū had a designed aircraft capacity of 64, plus nine spares. Hiryū's primary anti-aircraft armament consisted of six twin-gun mounts equipped with 40-caliber 12.7-centimeter Type 89 dual-purpose guns mounted on projecting sponsons, three on either side of the carrier's hull.
When firing at surface targets, the guns had a range of 14,700 meters. Their maximum rate of fire was 14 rounds a minute, but their sustained rate of fire was eight rounds per minute; the ship was equipped with two Type 94 fire-control directors to control the 12.7-centimeter guns, one for each side of the ship. The ship's light AA armament consisted of seven triple and five twin-gun mounts for license-built Hotchkiss 25 mm Type 96 AA guns. Two of the triple mounts were sited on a platform just below the forward end of the flight deck; the gun was the standard Japanese light AA gun during World War II, but it suffered from severe design shortcomings that rendered it ineffective. According to historian Mark Stille, the weapon had many faults including an inability to "handle high-speed targets because it could
The Yamato-class battleships were battleships of the Imperial Japanese Navy constructed and operated during World War II. Displacing 72,000 long tons at full load, the vessels were the heaviest battleships constructed; the class carried the largest naval artillery fitted to a warship, nine 460-millimetre naval guns, each capable of firing 1,460 kg shells over 42 km. Two battleships of the class were completed, while a third was converted to an aircraft carrier during construction. Due to the threat of American submarines and aircraft carriers, both Yamato and Musashi spent the majority of their careers in naval bases at Brunei and Kure—deploying on several occasions in response to American raids on Japanese bases—before participating in the Battle of Leyte Gulf in October 1944, as part of Admiral Kurita's Centre Force. Musashi was sunk during the battle by American carrier airplanes. Shinano was sunk ten days after her commissioning in November 1944 by the submarine USS Archerfish, while Yamato was sunk by US naval air power in April 1945 during Operation Ten-Go.
The design of the Yamato-class battleships was shaped by expansionist movements within the Japanese government, Japanese industrial power, the need for a fleet powerful enough to intimidate adversaries. After the end of the First World War, many navies—including those of the United States, the United Kingdom, Imperial Japan—continued and expanded construction programs that had begun during the conflict; the enormous costs associated with these programs pressured their government leaders to begin a disarmament conference. On 8 July 1921, the United States' Secretary of State Charles Evans Hughes invited delegations from the other major maritime powers—France, Italy and the United Kingdom—to come to Washington, D. C. and discuss a possible end to the naval arms race. The subsequent Washington Naval Conference resulted in the Washington Naval Treaty. Along with many other provisions, it limited all future battleships to a standard displacement of 35,000 long tons and a maximum gun caliber of 16 inches.
It agreed that the five countries would not construct more capital ships for ten years and would not replace any ship that survived the treaty until it was at least twenty years old. In the 1930s, the Japanese government began a shift towards ultranationalist militancy; this movement called for the expansion of the Japanese Empire to include much of the Pacific Ocean and Southeast Asia. The maintenance of such an empire—spanning 3,000 miles from China to Midway Island—required a sizable fleet capable of sustained control of territory. Although all of Japan's battleships built prior to the Yamato class had been completed before 1921—as the Washington Treaty had prevented any more from being completed—all had been either reconstructed or modernized, or both, in the 1930s; this modernization included, among other things, additional speed and firepower, which the Japanese intended to use to conquer and defend their aspired-to empire. When Japan withdrew from the League of Nations in 1934 over the Mukden Incident, it renounced all treaty obligations.
Japan would no longer design battleships within the treaty limitations and was free to build warships larger than those of the other major maritime powers. Japan's intention to acquire resource-producing colonies in the Pacific and Southeast Asia would lead to confrontation with the United States, thus the U. S. became Japan's primary potential enemy. The U. S. possessed greater industrial power than Japan, with 32.2% of worldwide industrial production compared to Japan's 3.5%. Furthermore, several leading members of the United States Congress had pledged "to outbuild Japan three to one in a naval race." As Japanese industrial output could not compete with American industrial power, Japanese ship designers developed plans for new battleships individually superior to their counterparts in the United States Navy. Each of these battleships would be capable of engaging multiple enemy capital ships eliminating the need to expend as much industrial effort as the U. S. on battleship construction. Preliminary studies for a new class of battleships began after Japan's departure from the League of Nations and its renunciation of the Washington and London naval treaties.
These early plans varied in armament, propulsion and armor. Main batteries fluctuated between 460 mm and 406 mm guns, while the secondary armaments were composed of differing numbers of 155 mm, 127 mm, 25 mm guns. Propulsion in most of the designs was a hybrid diesel-turbine combination, though one relied on diesel and another planned for only turbines. Endurance in the designs had, at 18 kn, a low of 6,000 nmi in design A-140-J2 to a high of 9,200 nmi in designs A-140A and A-140-B2. Armor varied between providing protection from the fire of 406 mm guns to enough protection against 460 mm guns. After these had been reviewed, two of the original twenty-four were finalized as possibilities, A-140-F3 and A-140-F4. Differing in their range, they were used in the formation of the final preliminary study, finished on 20 July 1936. Tweaks to that design resulted in the definitive design of March 1937, put forth by Rear-Admiral Fukuda Keiji; the diesels were removed from the
Shimane Maru-class escort carrier
The Shimane Maru class was a pair of auxiliary escort carriers built for the Imperial Japanese Navy during World War II. Four additional conversions were considered but not carried out. Although both ships were launched, only one was completed, neither entered active service before being destroyed; the concept of the class was similar to British merchant aircraft carrier. The class consisted of two oil tankers of 10,002 gross register tons that were modified by the Navy to provide minimal anti-submarine air cover for convoys going from Southeast Asia to the Japanese homeland; the conversion consisted of fitting a full-length flight deck, a small hangar, a single elevator. An island and catapults were not installed; the only other change was the rerouting of the boiler uptakes to the aft starboard side where they discharged in a typical downward-facing funnel. The ships had a length of 150 meters between perpendiculars, they had a beam of a mean draft of 9.1 meters. They displaced 11,989 metric tons at standard load.
The Shimane Maru-class ships were fitted with a single geared steam turbine set with a total of 8,600 shaft horsepower. It drove one propeller shaft using steam provided by two boilers; the ships had a range of 10,000 nautical miles at 10 knots. The flight deck had a maximum width of 23.01 meters. The hangar, built on top of the well deck, was served by a single elevator from the flight deck, it had a capacity of a dozen aircraft. She was completed on 28 February 1945, but was sunk 24 July 1945 by British aircraft at Shido Bay, Kagawa Prefecture at position 34°20′10″N 134°10′15″E, her hulk was mined scrapped at Naniwa in 1948. Her construction was 70 % completed when she sank, her hulk was scrapped at Kobe in 1948. Daiju Maru - Laid down by Kawasaki on 18 December 1944, construction stopped in February 1945. Constructions were restarted and sold to Iino Lines K. K. on 19 October 1949, renamed Ryūhō Maru. Scrapped at Yokosuka in May 1964. Taisha Maru - Cancelled in 1944. Chesneau, Roger. Aircraft Carriers of the World, 1914 to the Present: An Illustrated Encyclopedia.
Annapolis, Maryland: Naval Institute Press. ISBN 0-87021-902-2. Chesneau, Roger, ed.. Conway's All the World's Fighting Ships 1922-1946. Greenwich, UK: Conway Maritime Press. ISBN 0-85177-146-7. Fukui, Shizuo. Japanese Naval Vessels at the End of World War II. London: Greenhill Books. ISBN 1-85367-125-8. Jentschura, Hansgeorg. Warships of the Imperial Japanese Navy, 1869–1945. Annapolis, Maryland: United States Naval Institute. ISBN 0-87021-893-X. Polmar, Norman. Aircraft Carriers: A History of Carrier Aviation and Its Influence on World Events. Volume 1, 1909–1945. Washington, D. C.: Potomac Books. ISBN 1-57488-663-0; the Maru Special, Japanese Naval Vessels No. 38, Japanese aircraft carriers II, Ushio Shobō