Tone class cruiser
Encyclopedia
The two were the last heavy cruiser
s produced for the Imperial Japanese Navy
. The Tone class cruisers were originally envisaged as the 5th and 6th vessels in the Mogami class
. However, by the time construction began, serious weaknesses in the Mogami-class hull design had become clear following the Fourth Fleet Incident in 1935. As Japan no longer was obligated to abide by the limitations of the London Naval Treaty
, a new design was created and new means of construction were utilized. Though the external dimensions were close to the Mogami class, the design was quite different, with all the main battery of guns placed forward of the bridge, reserving the entire stern area as a large sea plane hanger. Unlike the U.S. Navy, the Japanese did not have a dual role attack/scout aircraft, nor did they assign any of their carrier aircraft to a reconnaissance role. Little emphasis was placed on this aspect of carrier warfare. Instead the Japanese reserved all of their carrier aircraft for attack roles. Reconnaissance then was relegated to the float planes carried by cruisers. The Tone and the Chikuma were intended to provide the long range reconnaissance needed for Japan's carrier
Air Fleets.
called into question the stability of all Japanese warship designs. As a result of the redesign, and to improve accuracy of gunfire, all five turrets in the new design were concentrated on the forecastle. When Japan abrogated the Washington Naval Treaty
on 31 December 1936, the main armament was revised to eight 203 mm guns in four twin turrets with maximum 55 degree elevation, as was installed on the Mogami class vessels. No. 1 was forward firing, No. 3 and No. 4 turrets trained through after arcs, while No. 2 was on a superfiring
pedestal mounting overlooking No.1 and No.3.
Heavy anti-aircraft weaponry consisted of four twin 127 mm gun turrets in shielded mountings amidships. For close-range, six twin 25mm Type 96 25 mm AT/AA Guns were carried. Four triple banks of 610 mm torpedo tubes were also incorporated.
to about 12,500 tons. The main belt armor was 150 mm thick next to machinery spaces (225mm next to magazines), and it extended to a depth of about 9 feet, beyond which it had a much reduced thickness as an anti-torpedo bulkhead down to the inner double bottom.
and quarterdecks. Two gunpowder-propelled catapults were located on the beam abaft the mainmast. A maximum of four Kawanishi E7K
2 'Alf' three-seat floatplanes and four Nakajima E8N
1 'Dave' floatplane
s could be carried, the normal complement being six, of which four were to be E8Nls. In practice, no more than five were ever embarked. As the war progressed these types were superseded by the Aichi E13A
1 'Jake' and Mitsubishi F1M
2 'Pete'.
was fitted, but otherwise no major modifications were carried out.
at the Nagasaki shipyards.
, and the following month it assisted in the second Battle of Wake Island
. Subsequently, Tone was involved in operations in the Netherlands East Indies. In February 1942, it was part of the covering force for the carrier raid on Darwin, and in March accompanied the battleships Hiei
and Kirishima
in the sinking of the . During March Tone participated in the strike by Admiral Nagumo's carrier force into the Indian Ocean
and the attack on Ceylon. Tone returned to the Pacific for the Battle of Midway
in May, and from the summer of 1942 was part of the Guadalcanal
campaign. On 2 August 1942, Tone was damaged by aircraft from . In 1943, Tone patrolled in Solomon Islands
theatre where it was damaged by an air raid on its base in Rabaul
on 5 November. In the beginning of 1944, Tone participated in a strike into the Indian Ocean
against Allied shipping on the Australia
-Aden
route. Later, Tone was in the Battle of the Philippine Sea
, and as part of Admiral Kurita's Centre Force at the Battle of Leyte Gulf
attacked US escort aircraft carrier
s. Tone was damaged by US aircraft in March 1945, after her return to home water and was finally sunk by aircraft, near Kure
, on 24 July 1945. She was raised postwar and broken up at Kure in 1948.
, Chikuma was hit by five bombs dropped by aircraft from . Chikuma was lost in the Battle off Samar
on 25 October 1944.
Heavy cruiser
The heavy cruiser was a type of cruiser, a naval warship designed for long range, high speed and an armament of naval guns roughly 203mm calibre . The heavy cruiser can be seen as a lineage of ship design from 1915 until 1945, although the term 'heavy cruiser' only came into formal use in 1930...
s produced for the Imperial Japanese Navy
Imperial Japanese Navy
The Imperial Japanese Navy was the navy of the Empire of Japan from 1869 until 1947, when it was dissolved following Japan's constitutional renunciation of the use of force as a means of settling international disputes...
. The Tone class cruisers were originally envisaged as the 5th and 6th vessels in the Mogami class
Mogami class cruiser
The were a class of four heavy cruisers built for the Imperial Japanese Navy in the mid-1930s. All four fought in World War II, and were sunk.-Design:...
. However, by the time construction began, serious weaknesses in the Mogami-class hull design had become clear following the Fourth Fleet Incident in 1935. As Japan no longer was obligated to abide by the limitations of the London Naval Treaty
London Naval Treaty
The London Naval Treaty was an agreement between the United Kingdom, the Empire of Japan, France, Italy and the United States, signed on April 22, 1930, which regulated submarine warfare and limited naval shipbuilding. Ratifications were exchanged in London on October 27, 1930, and the treaty went...
, a new design was created and new means of construction were utilized. Though the external dimensions were close to the Mogami class, the design was quite different, with all the main battery of guns placed forward of the bridge, reserving the entire stern area as a large sea plane hanger. Unlike the U.S. Navy, the Japanese did not have a dual role attack/scout aircraft, nor did they assign any of their carrier aircraft to a reconnaissance role. Little emphasis was placed on this aspect of carrier warfare. Instead the Japanese reserved all of their carrier aircraft for attack roles. Reconnaissance then was relegated to the float planes carried by cruisers. The Tone and the Chikuma were intended to provide the long range reconnaissance needed for Japan's carrier
Aircraft carrier
An aircraft carrier is a warship designed with a primary mission of deploying and recovering aircraft, acting as a seagoing airbase. Aircraft carriers thus allow a naval force to project air power worldwide without having to depend on local bases for staging aircraft operations...
Air Fleets.
Overview
The Tone class cruisers had a very distinctive silhouette, with all main armament concentrated forward and the aft section entirely devoted to aircraft operations. This allowed for strong and compact protection of the magazines while also increasing and improving the living quarters aft.Armament
As originally planned, the Tone class vessels were to have five triple 155 mm turrets, three forward and two aft. However, the capsizing of the torpedo boat TomozuruJapanese torpedo boat Tomozuru
was one of four s of the Imperial Japanese Navy. She capsized in a storm on March 12, 1934, shortly after her completion. This incident forced the IJN to review the stability of all recently completed, under construction and planned ships. She was salvaged and put back into service after extensive...
called into question the stability of all Japanese warship designs. As a result of the redesign, and to improve accuracy of gunfire, all five turrets in the new design were concentrated on the forecastle. When Japan abrogated the Washington Naval Treaty
Washington Naval Treaty
The Washington Naval Treaty, also known as the Five-Power Treaty, was an attempt to cap and limit, and "prevent 'further' costly escalation" of the naval arms race that had begun after World War I between various International powers, each of which had significant naval fleets. The treaty was...
on 31 December 1936, the main armament was revised to eight 203 mm guns in four twin turrets with maximum 55 degree elevation, as was installed on the Mogami class vessels. No. 1 was forward firing, No. 3 and No. 4 turrets trained through after arcs, while No. 2 was on a superfiring
Superfire
The idea of superfire is to locate two turrets in a row, one behind the other, but with the second turret located above the one in front so that the second turret could fire over the first...
pedestal mounting overlooking No.1 and No.3.
Heavy anti-aircraft weaponry consisted of four twin 127 mm gun turrets in shielded mountings amidships. For close-range, six twin 25mm Type 96 25 mm AT/AA Guns were carried. Four triple banks of 610 mm torpedo tubes were also incorporated.
Hull & Armor
The previous Mogami-class experimented with welded hulls, with limited success. Thus the lead vessel in the Tone-class, Tone, also had some welding, the subsequent Chikuma was an all riveted design. The undulating hull of earlier cruisers was dispensed with and the superstructure was less built-up. The modifications to the design raised the nominal displacementDisplacement (ship)
A ship's displacement is its weight at any given time, generally expressed in metric tons or long tons. The term is often used to mean the ship's weight when it is loaded to its maximum capacity. A number of synonymous terms exist for this maximum weight, such as loaded displacement, full load...
to about 12,500 tons. The main belt armor was 150 mm thick next to machinery spaces (225mm next to magazines), and it extended to a depth of about 9 feet, beyond which it had a much reduced thickness as an anti-torpedo bulkhead down to the inner double bottom.
Engines
The main engines of the Tone class were similar to that of the Suzuya and Kumano.He Had 2 enginesAircraft
The Tone class had no aircraft hangar, but there was a comprehensive arrangement of transport rails and turntables on the aircraft catapultAircraft catapult
An aircraft catapult is a device used to launch aircraft from ships—in particular aircraft carriers—as a form of assisted take off. It consists of a track built into the flight deck, below which is a large piston or shuttle that is attached through the track to the nose gear of the aircraft, or in...
and quarterdecks. Two gunpowder-propelled catapults were located on the beam abaft the mainmast. A maximum of four Kawanishi E7K
Kawanishi E7K
-See also:-References:NotesBibliography* Francillon, Ph.D., Réne J. Japanese Aircraft of the Pacific War. London: Putnam & Company Ltd., 1970 . ISBN 0-370-30251-6....
2 'Alf' three-seat floatplanes and four Nakajima E8N
Nakajima E8N
|-See also:-References:*Francillon, R.J. Japanese Aircraft of the Pacific War. London:Putnam, 1970. ISBN 0 370 00033 1....
1 'Dave' floatplane
Floatplane
A floatplane is a type of seaplane, with slender pontoons mounted under the fuselage; only the floats of a floatplane normally come into contact with water, with the fuselage remaining above water...
s could be carried, the normal complement being six, of which four were to be E8Nls. In practice, no more than five were ever embarked. As the war progressed these types were superseded by the Aichi E13A
Aichi E13A
-See also:-References:NotesBibliography* Dorr, Robert E. and Chris Bishop. Vietnam Air War Debrief. London: Aerospace Publishing, 1996. ISBN 1-874023-78-6....
1 'Jake' and Mitsubishi F1M
Mitsubishi F1M
-See also:-Bibliography:* Francillon, R.J. Japanese Aircraft of the Pacific War. London:Putnam, 1970. ISBN 370 00033 1.* Green, William. War Planes of the Second World War, Volume Six: Floatplanes. London: Macdonald & Co., Ltd., 1962....
2 'Pete'.
Modifications
In 1943, the number of 25 mm guns was increased to twenty guns, and in June 1944, when the opportunity to use their aircraft had passed, further mountings were added on the flight deck, bringing the light anti-aircraft total to 54 barrels. Two more twin 25 mm guns were also added later. RadarRadar
Radar is an object-detection system which uses radio waves to determine the range, altitude, direction, or speed of objects. It can be used to detect aircraft, ships, spacecraft, guided missiles, motor vehicles, weather formations, and terrain. The radar dish or antenna transmits pulses of radio...
was fitted, but otherwise no major modifications were carried out.
Ships in class
Two ships were funded under the 1932 2nd Supplementary Budget, both of which were built by MitsubishiMitsubishi Heavy Industries
, or MHI, is a Japanese company. It is one of the core companies of Mitsubishi Group.-History:In 1870 Yataro Iwasaki, the founder of Mitsubishi took a lease of Government-owned Nagasaki Shipyard. He named it Nagasaki Shipyard & Machinery Works, and started the shipbuilding business on a full scale...
at the Nagasaki shipyards.
Tone
Tone (利根) was part of the covering force for the attack on Pearl HarborAttack on Pearl Harbor
The attack on Pearl Harbor was a surprise military strike conducted by the Imperial Japanese Navy against the United States naval base at Pearl Harbor, Hawaii, on the morning of December 7, 1941...
, and the following month it assisted in the second Battle of Wake Island
Battle of Wake Island
The Battle of Wake Island began simultaneously with the Attack on Pearl Harbor and ended on 23 December 1941, with the surrender of the American forces to the Empire of Japan...
. Subsequently, Tone was involved in operations in the Netherlands East Indies. In February 1942, it was part of the covering force for the carrier raid on Darwin, and in March accompanied the battleships Hiei
Japanese battleship Hiei
was a warship of the Imperial Japanese Navy during World War I and World War II. Designed by British naval architect George Thurston, she was the second launched of four s, among the most heavily armed ships in any navy when built. Laid down in 1911 at the Yokosuka Naval Arsenal, Hiei was formally...
and Kirishima
Japanese battleship Kirishima
was a warship of the Imperial Japanese Navy during World War I and World War II. Designed by British naval engineer George Thurston, she was the third launched of the four Kongō-class battlecruisers, among the most heavily armed ships in any navy when built...
in the sinking of the . During March Tone participated in the strike by Admiral Nagumo's carrier force into the Indian Ocean
Indian Ocean
The Indian Ocean is the third largest of the world's oceanic divisions, covering approximately 20% of the water on the Earth's surface. It is bounded on the north by the Indian Subcontinent and Arabian Peninsula ; on the west by eastern Africa; on the east by Indochina, the Sunda Islands, and...
and the attack on Ceylon. Tone returned to the Pacific for the Battle of Midway
Battle of Midway
The Battle of Midway is widely regarded as the most important naval battle of the Pacific Campaign of World War II. Between 4 and 7 June 1942, approximately one month after the Battle of the Coral Sea and six months after Japan's attack on Pearl Harbor, the United States Navy decisively defeated...
in May, and from the summer of 1942 was part of the Guadalcanal
Guadalcanal
Guadalcanal is a tropical island in the South-Western Pacific. The largest island in the Solomons, it was discovered by the Spanish expedition of Alvaro de Mendaña in 1568...
campaign. On 2 August 1942, Tone was damaged by aircraft from . In 1943, Tone patrolled in Solomon Islands
Solomon Islands
Solomon Islands is a sovereign state in Oceania, east of Papua New Guinea, consisting of nearly one thousand islands. It covers a land mass of . The capital, Honiara, is located on the island of Guadalcanal...
theatre where it was damaged by an air raid on its base in Rabaul
Rabaul
Rabaul is a township in East New Britain province, Papua New Guinea. The town was the provincial capital and most important settlement in the province until it was destroyed in 1994 by falling ash of a volcanic eruption. During the eruption, ash was sent thousands of metres into the air and the...
on 5 November. In the beginning of 1944, Tone participated in a strike into the Indian Ocean
Japanese Indian Ocean raid (1944)
In March 1944, a force of three Imperial Japanese Navy heavy cruisers raided Allied shipping in the Indian Ocean. The cruisers departed Japanese territory on 1 March with the support of other IJN vessels and aircraft. On 9 March, they encountered and sank the British steamer Behar, with the heavy...
against Allied shipping on the Australia
Australia
Australia , officially the Commonwealth of Australia, is a country in the Southern Hemisphere comprising the mainland of the Australian continent, the island of Tasmania, and numerous smaller islands in the Indian and Pacific Oceans. It is the world's sixth-largest country by total area...
-Aden
Aden
Aden is a seaport city in Yemen, located by the eastern approach to the Red Sea , some 170 kilometres east of Bab-el-Mandeb. Its population is approximately 800,000. Aden's ancient, natural harbour lies in the crater of an extinct volcano which now forms a peninsula, joined to the mainland by a...
route. Later, Tone was in the Battle of the Philippine Sea
Battle of the Philippine Sea
The Battle of the Philippine Sea was a decisive naval battle of World War II which effectively eliminated the Imperial Japanese Navy's ability to conduct large-scale carrier actions. It took place during the United States' amphibious invasion of the Mariana Islands during the Pacific War...
, and as part of Admiral Kurita's Centre Force at the Battle of Leyte Gulf
Battle of Leyte Gulf
The Battle of Leyte Gulf, also called the "Battles for Leyte Gulf", and formerly known as the "Second Battle of the Philippine Sea", is generally considered to be the largest naval battle of World War II and, by some criteria, possibly the largest naval battle in history.It was fought in waters...
attacked US escort aircraft carrier
Aircraft carrier
An aircraft carrier is a warship designed with a primary mission of deploying and recovering aircraft, acting as a seagoing airbase. Aircraft carriers thus allow a naval force to project air power worldwide without having to depend on local bases for staging aircraft operations...
s. Tone was damaged by US aircraft in March 1945, after her return to home water and was finally sunk by aircraft, near Kure
Kure, Hiroshima
is a city in Hiroshima prefecture, Japan.As of October 1, 2010, the city has an estimated population of 240,820 and a population density of 681 persons per km². The total area is 353.74 km².- History :...
, on 24 July 1945. She was raised postwar and broken up at Kure in 1948.
Chikuma
The career of Chikuma (筑摩) parallels that of Tone in almost every detail, since both ships formed the 8th Cruiser Squadron on completion and operated together for almost all of their careers. In October 1942, during the Battle of the Santa Cruz IslandsBattle of the Santa Cruz Islands
The Battle of the Santa Cruz Islands, 26 October 1942, sometimes referred to as the Battle of Santa Cruz or in Japanese sources as the , was the fourth carrier battle of the Pacific campaign of World War II and the fourth major naval engagement fought between the United States Navy and the Imperial...
, Chikuma was hit by five bombs dropped by aircraft from . Chikuma was lost in the Battle off Samar
Battle off Samar
The Battle off Samar was the centermost action of the Battle of Leyte Gulf, one of the largest naval battles in history, which took place in the Philippine Sea off Samar Island, in the Philippines on 25 October 1944...
on 25 October 1944.