Class overview

Name: Soryu
Namesake: Japanese: 蒼龍, meaning "Blue (or Green) Dragon"
Laid down: 20 November 1934
Launched: 23 December 1935
Commissioned: 29 December 1937
Struck: 10 August 1942
Fate: Sunk by air attack at the Battle of Midway, 4 June 1942

General characteristics

Class & type: Sōryū class aircraft carrier
Displacement: 15,900 tons (standard), 19,500 tons (full load)
Length: 222 m (728 ft 5 in)
Beam: 21 m (70 ft)
Draught: 7.44 m (24 ft 5 in)
Propulsion: Geared steam turbines, 113 MW (152,000 hp), 4 screws
Speed: 63.9 km/h (34.5 knots)
Complement: 1,103
Armament: 12 × 127 mm (5 in) DP guns, (dual-purpose), 26 × 25 mm anti-aircraft guns, 15 × 13.2 mm machine guns
Aircraft carried: 57(+16) 18 Mitsubishi A6M Zero, 18 Aichi D3A Vals, 18 Nakajima B5N Kates (Dec. 1941)

Service record

Carrier Division 2

Operations: World War II - Pacific War

Attack on Pearl Harbor - Indian Ocean raid of March–April 1942 - Operation Mo (the planned capture of Port Moresby in New Guinea) - Battle of Midway

Sōryū (Japanese 蒼龍 Sōryū, meaning ‘blue (or green) dragon’) was an aircraft carrier of the Imperial Japanese Navy. She took part in the attack on Pearl Harbor and was sunk at the battle of Midway.

Soryu (蒼龍 Sōryū, meaning 'Blue (or Green) Dragon') was an aircraft carrier of the Imperial Japanese Navy. During the Second World War, she took part in the attack on Attack on Pearl Harbor, Wake Island, Port Darwin and raids in the Indian Ocean before being sunk at the Battle of Midway.^[1]

Design

Sōryū was one of two large carriers approved for construction under the 1931-32 Supplementary Programme (the other being her sister-ship Hiryū). She was laid down at Kaigun Kosho, Kure, Japan on 20 November 1934, launched on 21 December 1935 and finally commissioned on 29 December 1937.^[1] As opposed to some earlier Japanese carriers, which were conversions of battlecruiser (Akagi) or battleship (Kaga) hulls, Sōryū was designed from the keel up as an aircraft carrier and incorporated lessons learned from the light carrier Ryujo.^[2]

Hull

Sōryū featured a slim cruiser-type hull with a length-to-beam ratio of 10:1. Primary protection from horizontal fire came from a 46 mm (1.8 in) waterline armor belt of Ducol Steel plate along with a separate internal anti-splinter bulkhead. Vertical protection consisted of 25 mm (0.98 in) of armor over the ship's machinery and 55 mm (2.2 in) over the fore and aft magazines and aviation fuel tanks. There were no bulges on the hull for anti-torpedo defense.^[3]

Machinery

Sōryū's machinery was similar to that of the Mogami-class heavy cruisers and consisted of four sets of geared turbines, developing 152,000 shp (113,000 kW), connected to four propeller shafts. Steam power was generated from eight oil-fired Kampon boilers. With a maximum bunkerage capacity of 3670 tons of fuel oil, Sōryū could cruise 7,750 nautical miles (14,350 km; 8,920 mi) at 18 knots (33 km/h; 21 mph).

Corrosive exhaust gases were trunked upward through the ship and vented out a pair of downward-curving horizontal funnels located amidships on the starboard side, just abaft the carrier's island. This arrangement prevented smoke from interfering with flight operations in most wind conditions.^[4]

The carrier's slender hull and powerful machinery resulted in a high maximum speed. Reaching close to 65 km/h (35 kts)^[1] during initial sea trials, Sōryū was the fastest carrier in the world at the time of her commissioning.

Flight Deck & Hangars

The carrier's 217 m (712 ft) long flight deck overhung both ends of the hangar box but stopped short of the bow and stern. It was supported fore and aft by steel girders. Sōryū's diminutive island sat atop a starboard-side extension jutting beyond the side of the hull and therefore did not encroach on the width of the flight deck. Nine Type 4 electrically operated arrester wires were capable of stopping a 6,000 kg (13,000 lb) aircraft at speeds of 60-78 knots.^[3]

To facilitate rapid transfer of aircraft from hangar to flight deck and back, Sōryū was designed with three elevators. The largest of these was located along the ship's center line abreast the island. Two somewhat smaller elevators were offset to starboard, one just abaft the ship's funnels and one located further aft. They were capable of transferring aircraft weighing up to 5,000 kg (11,000 lb).^[3] Sōryū had two fully enclosed aircraft hangars, arranged one atop the other, with the 160 m (520 ft) upper hangar being approximately 30.5 m (100 ft) longer than the lower. Overhead clearance was limited to 4.5 m (15 ft) in the upper hangar (where the wings of a Nakajima B5N Kate torpedo bomber could therefore not be spread for maintenance purposes) and less than 4.25 m (13.9 ft) in the lower one where the top of the engine cowling of a Mitsubishi A6M Zero fighter came within 1.2 m (3.9 ft) of the deck-head.^[4][5]

AA Armament

Heavy AA armament consisted of six twin batteries of 127 mm (5.0 in) dual-purpose guns mounted below flight deck level on either side of the ship (three sited forward and three aft). Each was controlled by a Type 94 fire-control director. A seventh director was mounted atop the island and could control all six batteries if necessary though at a reduced rate of fire.^[4]

Close-in AA armament consisted of fourteen twin 25 mm (0.98 in) AA guns distributed along the sides of the ship, again below flight deck level. Three of them were sited on a platform just below the bow end of the flight deck.^[4][5]

World War II

 

Pearl Harbor and subsequent operations

Operational history

At the outbreak of the Pacific War, commanded by Captain Ryusaku Yanagimoto, Sōryū, in Carrier Division 2, was one of six carriers comprising the Kido Butai (Striking Force) that attacked Pearl Harbor on 7 December 1941. She launched two waves of air strikes against the U.S. naval base. Her first wave targeted Nevada, Tennessee, and West Virginia with armour-piercing bombs and Utah, Helena, California, and Raleigh with torpedoes, and also attacked parked aircraft at Barbers Point. Her second wave targeted California, Raleigh, Kaneohe and Navy Yard installations.

Wake Island / Port Darwin

From 21 December to 23 December 1941 Sōryū launched air strikes against Wake Island. In January 1942 she supported the invasion of the Palau Islands and the Battle of Ambon. On 19 February 1942 Sōryū launched air strikes against Darwin, Australia. In March 1942 she took part in the Battle of the Java Sea, helping sink the US tanker Pecos.

Indian Ocean

In April 1942 Sōryū took part in the Indian Ocean raid, launching air strikes against the Royal Navy base at Ceylon on 5 April 1942, and assisted in sinking the Royal Navy cruisers Cornwall and Dorsetshire. On 9 April her aircraft contributed to torpedoes that sank the British carrier Hermes and the escorting Australian destroyer HMAS Vampire.

On 19 April 1942 she pursued the American carriers Hornet and Enterprise after they launched the Doolittle Raid, but without success.

Battle of Midway

In June 1942 Sōryū was one of four carriers with Vice Admiral Chuichi Nagumo's First Carrier Striking Force in the battle of Midway. Her aircraft complement consisted of 21 Mitsubishi A6M 'Zero' fighters, 21 Aichi D3A 'Val' dive bombers, and 21 Nakajima B5N 'Kate' torpedo bombers. ^[1] On 4 June 1942 she launched her first wave of planes against the American base on Midway Island. At 10:25 AM while preparing to launch a second strike against an American carrier group, she was attacked by thirteen SBD Dauntless dive bombers from the American carrier Yorktown. Sōryū received three direct hits from 454 kg (1000 lb) bombs: one penetrated to the lower hangar deck, and the other two exploded in the upper hangar deck. The hangars contained armed and fueled aircraft preparing for the upcoming strike, resulting in secondary explosions. Within a very short time the fires on the ship were out of control. At 10:40 AM she stopped and her crew were taken off by the destroyers Isokaze and Hamakaze. Sōryū sank at 7:13 PM at position 30°38′N 179°13′W . Losses were 711 crew of her nominal complement of 1103, including Captain Yanagimoto, who chose to remain on board. This was the highest mortality percentage of all the Japanese carriers lost at Midway, due largely to the devastation in both hangar decks.^[1]

The official record (the Nagumo Report) implies that Sōryū sank of her own accord. Later research has revealed she was scuttled with torpedoes by Isokaze.

Commanding Officers:

• Chief Equipping Officer - Capt. Ichiro Ono - 23 December 1935 - 1 April 1936
• Chief Equipping Officer - Capt. Takeo Okumoto - 1 April 1936 - 1 December 1936
• Chief Equipping Officer - Capt. Akitomo Beppu - 1 Dec 1936 - 16 August 1937
• Capt. Akitomo Beppu - 16 August 1937 - 1 December 1937
• Capt. Kinpei Teraoka - 1 December 1937 - 15 November 1938
• Capt. Keizo Uwano - 15 November 1938 - 15 October 1939
• Capt. Sadayoshi Yamada - 15 October 1939 - 15 October 1940
• Capt. Wataru Kamase - 15 October 1940 - 25 November 1940
• Capt. Kanae Kosaka - 25 November 1940 - 12 September 1941
• Capt. Kiichi Hasegawa - 12 September 1941 - 6 October 1941
• Capt./RADM Ryusaku Yanagimoto - 6 October 1941 - 4 June 1942 (KIA)

IJN Soryu: Tabular Record of Movement

Initial Command Structure: Commanding Officer: Captain Yanagimito Ryusaku.

• 10 April 1941: Assigned to 1st Air Fleet, CarDiv 2.
• 10 July 1941: Assigned to "FU" Escort Fleet, participated in "FU" Operations from 10 - 31 July. Depart Yokosuka.
• 14 July 1941: Arrive Mako.
• 16 July 1941: Arrive at Sama.
• 25 July 1941: Depart.
• 29-30 July 1941: Stop at Condor and St. James respectively.
• 1 August 1941: Arrive at Sama.
• 7 August 1941: Arrive at Kagoshima, assigned as flagship ComCarDiv 2. Thereafter in Kyushu waters till end of month.
• 6 September 1941: Depart Kagoshima for Tokyo Bay.
• 8 September 1941: Arrive Yokosuka.
• 22 September 1941: Flag removed. Enter drydock.
• 8 October 1941: Leave drydock.
• 24 October 1941: Depart Yokosuka.
• 26 October 1941: Arrive at Kagoshima; recieve flag of ComCarDiv 2.
• 19 November 1941: Depart Kure for Hitokappu Bay.
• 22 November 1941: Arrive Hitokappu Bay.
• 26 November 1941: Assigned to Striking Force Main Body, CarDiv 2.
• 27 November 1941: Depart Hitokappu Bay for the "Hawaii" Operation.
• 7 December 1941: Launch two attack waves against Pearl Harbor, Hawaii.
• 16 December 1941: Detached from Striking Force Main Body with HIRYU to participate strikes against Wake Island.
• 21 - 23 December 1941: Launch strikes against Wake Island, thereafter headed for the homeland.
• 29 December 1941: Return to Kure.
• 8 January 1942: Assigned to Southern Force (Carrier Air Force).
• 12 January 1942: Depart Kure for combat zone.
• 17 January 1942: Arrive at Palau.
• 21 January 1942: Depart Palau.
• 23 - 24 January 1942: Launch strikes against Ambon.
• 25 January 1942: Arrive Davao.
• 27 January 1942: Depart Davao for Palau.
• 28 January 1942: Arrive Palau.
• 10 February 1942: Reassigned to Southern Force Striking Force.
• 16 February 1942: Depart Palau.
• 19 February 1942: Launch strikes against Port Darwin, Australia.
• 21 February 1942: Arrive at Staring Bay.
• 25 February 1942: Depart Staring Bay to participate in Java Operations.
• 1 March 1942: Operating south of Sunda Strait to intercept enemy shipping fleeing from Java. Launch strikes that help sink tanker USS PECOS.
• 5 March 1942: Launch strike against enemy shipping at Tjilatjap.
• 7 March 1942: Launch strike against Christmas Island. Aircraft sink Dutch freighter POELAU BRAS.
• 11 March 1942: Return to Staring Bay.
• 26 March: With Striking Force (less KAGA) depart Staring Bay with BatDiv 3, Crudiv 8, and DesRon 1 for "Operation C" ---the raid into the Indian Ocean.
• 3 April 1942: Enter the Indian Ocean.
• 5 April 1942: Strikes launched against Royal Navy base at Ceylon. Important sinkings included the cruisers HMS CORNWALL and HMS DORSETSHIRE caught on the open sea.
• 9 April 1942: Strikes launched against Trincomalee. British carrier HMS HERMES caught at sea, bombed and sunk along with escort destroyer VAMPIRE.
• 18 April 1942: Arrive at Mako.
• 19 April 1942: Less CarDiv 5, which detaches with screen to head for New Guinea for "Operation MO" (Battleof the Coral Sea) operations, the Striking Force departs Mako in high speed attempted pursuit of the "Doolittle Raiders" - carriers USSHORNET and ENTERPRISE, which have just struck the Tokyo Bay area with aircraft on the 18th.
• 22 April 1942: Return to Hashirajima.
• 27 May 1942: Departed Hashirajima for the Midway Operation with VADM Nagumo's Carrier Striking Force (CarDivs 1,2). CarDiv 5 unable to participate, due to damage to SHOKAKU and aircraft losses to ZUIKAKU suffered at Coral Sea on 8 May.
• 3- 4 June 1942: Participate in the Battle of Midway. Launched strike against Midway Island.

At 1025 while making launch preparations against a sighted enemy carrier, attacked by thirteen enemy dive bombers. Three direct bomb hits are sustained, one on the forward elevator, the other two straddle the second elevator, setting off furious fires and induced explosions among the armed and fueled aircraft. At 1040 goes dead in the water; and five minutes later Abandon Ship is ordered. Survivors are removed by ISOKAZE and HAMAKAZE and vessel is left drifting and afire.

Sunk: Around 1920, apparently the order to scuttle SORYU along with KAGA is given.  At 1913 the destroyer ISOKAZE torpedoes SORYU (allegedly with three hits), and the carrier begins to sink by the stern and three minutes later upends.  Bow raised, she plunges to the bottom taking down 713 officers and men including Captain Yanagimoto Ryusaku, who had deliberately chosen to remain aboard. (Position 30 - 38' N, 179 - 13 W') (Note 1).

10 August 1942: Removed from the Navy list.

Note 1:  Heretofore the SORYU has been represented as sinking of her own accord around 1915, only ten minutes before the KAGA to the southwest.  However, in “Shattered Sword” it was argued by the writer with fellow author Jon Parshall that the evidence in fact clearly supports the mounting claims by veterans and modern Japanese sources that SORYU and KAGA were deliberately scuttled by torpedoes at sunset to free the screen for night counter-attack operations.