Shortly after completion in 1941,
Shōkaku and
Zuikaku were assigned to the newly formed
Fifth Carrier Division, which was itself assigned to the
1st Air Fleet (
Kidō Butai), and began
working up to prepare for the Pearl Harbor attack. Due to their inexperience, their air groups were tasked with the less demanding airfield attack role rather than the anti-ship mission allocated to the veteran air groups of the older carriers. Each carrier's aircraft complement consisted of 18 Zero fighters, 27 D3A dive bombers, and 27 B5N torpedo bombers. these latter aircraft struck
Wheeler Army Airfield,
Hickam Field, and
Naval Air Station Ford Island while the fighters
strafed Marine Corps Air Station Kaneohe Bay. Only the 54 B5Ns participated in the second wave, striking Ford Island, Hickam Field and Kaneohe Bay again. The Fifth Carrier Division's aircraft conducted the majority of the attack against the airfields, supplemented only by fighters from the other four carriers. Only one of
Shōkakus dive bombers was lost during the attack; in exchange 314 American aircraft were damaged or destroyed. Historian Alan Zimm said the young aviators delivered "a sterling performance, greatly exceeding expectations and outshining the dive bombers from the more experienced carriers." In January 1942, together with
Akagi and
Kaga of the
First Carrier Division, the sisters supported the
invasion of Rabaul in the
Bismarck Archipelago, as the Japanese moved to secure their southern defensive perimeter against attacks from Australia. Aircraft from all four carriers attacked the Australian base at Rabaul on 20 January; the First Carrier Division continued to attack the town while the Fifth Carrier Division moved westwards and attacked
Lae and
Salamaua in New Guinea. They covered the landings at Rabaul and
Kavieng on 23 January before returning to
Truk before the end of the month. After the
Marshalls–Gilberts raids on 1 February, the Fifth Carrier Division was retained in home waters until mid-March to defend against any American carrier raids on the
Home Islands.
Indian Ocean Raid The sister ships then rejoined the
Kido Butai at
Staring Bay on
Celebes Island in preparation for the Indian Ocean Raid. By this time the air groups had been reorganized to consist of 21 each of the A6Ms, D3As and B5Ns.
Shōkaku and
Zuikaku contributed aircraft to the 5 April
Easter Sunday Raid on
Colombo,
Ceylon. Although the civilian shipping had been evacuated from Colombo harbor, the Japanese sank an
armed merchant cruiser, a
destroyer, and severely damaged some of the support facilities. The
Kido Butai returned to Ceylon four days later and attacked Trincomalee; the sisters' aircraft sank a large
cargo ship and damaged the
monitor . In the meantime, the Japanese spotted the
light carrier , escorted by the destroyer , and every available D3A was launched to attack the ships. Aircraft from
Shōkaku and
Zuikaku were the first to attack the Allied ships, both of which were sunk.
Battle of the Coral Sea En route to Japan, the Fifth Carrier Division was diverted to Truk to support
Operation Mo (the planned capture of
Port Moresby in
New Guinea). While they were preparing for the mission, the Americans
intercepted and
decrypted Japanese naval messages discussing the operation and dispatched the carriers and to stop the invasion. The Japanese opened Operation Mo by occupying
Tulagi, in the
Solomon Islands, on 3 May. American land-based aircraft had spotted the light carrier escorting the transports of the main invasion force on 6 May, and the American carriers moved west to place themselves in a position to attack it the following morning.
Shōhō was quickly located again that morning and sunk. In turn, the Japanese spotted the
oiler, , and her escorting destroyer, which were misidentified as a carrier and a
light cruiser. A single dive bomber was lost during the consequent airstrike that sank the destroyer and damaged
Neosho badly enough that she had to be
scuttled a few days later. Late in the afternoon, the Japanese launched a small airstrike, without any escorting fighters, based on an erroneous spot report. The American carriers were far closer to the Japanese than they realized and roughly in line with their intended target. Alerted by radar, some of the American
Combat Air Patrol (CAP) was vectored to intercept the Japanese aircraft, the rest being retained near the carriers because of bad weather and fading daylight. The American fighters mauled the Japanese attackers who were forced to call off the attack, but some of the surviving Japanese pilots became confused in the darkness and attempted to verify if the American carriers were their own before being driven off. On the morning of 8 May 1942, both sides located each other at about the same time and began launching their aircraft about 09:00. The American dive bombers disabled
Shōkakus flight deck with three hits, but the carrier was able to evade all of the torpedoes. Hidden by a rain squall,
Zuikaku escaped detection and was not attacked. In return, the Japanese aircraft badly damaged
Lexington with two torpedo and two bomb hits and scored a single bomb hit on
Yorktown. The torpedo hits on
Lexington cracked one of her
avgas tanks, and leaking vapor caused a series of large explosions that caused her to be scuttled. The air groups of the sisters were decimated in the battle, which forced
Zuikaku to return to Japan with
Shōkaku for resupply and aircrew training, and neither carrier was able to take part in the
Battle of Midway in June. En route to Japan,
Shōkaku was caught in a severe storm and nearly capsized as the weight of the water used to put out the fires had compromised her stability. Repairs took three months and she was not ready for action until late August 1942.
Battle of the Eastern Solomons The
American landings on Guadalcanal and Tulagi on 7 August 1942 caught the Japanese by surprise. The next day, the light carrier joined the sister ships in the First Carrier Division, which departed for Truk on 16 August. Having learned the lesson taught at Midway, the IJN strengthened the fighter contingent at the expense of the torpedo bombers assigned to its carriers; the
Shōkaku-class carriers mustered 53 Zeros, 51 D3As, 36 B5Ns and 2
Yokosuka D4Y1-C "Judy" reconnaissance aircraft between them. After an American carrier was spotted near the Solomon Islands on 21 August, the division was ordered to bypass Truk and continue to the south.
Ryūjō was detached early on 24 August to move in advance of the troop convoy bound for
Guadalcanal and to attack the American air base at
Henderson Field if no carriers were located. The two fleet carriers were to stand off, prepared to attack the Americans if found.
Ryūjō and her escorts were the first Japanese ships spotted and sunk by the Americans later that morning, but
Zuikaku and
Shōkaku were not spotted until the afternoon. Shortly before an unsuccessful attack by the pair of
Douglas SBD Dauntlesses conducting the search, the sisters launched half of their dive bombers to attack the American carriers and . Most of the American carrier aircraft were already airborne by this time, either on CAP, returning from search missions, or from sinking
Ryūjō, so only a small airstrike was launched in response to the spot report. About an hour after the first Japanese airstrike took off, a second airstrike that included the rest of the dive bombers was launched, but their target location was mistaken and they failed to find the Americans. The first airstrike attacked the two American carriers, scoring one hit on the battleship and three hits on
Enterprise, but they were mauled by the large number of airborne American aircraft and heavy anti-aircraft fire. Uncertain of the damage inflicted on each other, both sides disengaged later that evening.
Battle of the Santa Cruz Islands The First Carrier Division, now including the light carrier , departed Truk on 11 October to support the Japanese Army operation to capture
Henderson Field on Guadalcanal. At this time, the sisters mustered 54 A6Ms, 45 D3As, and 36 B5Ns between them. Four days later, the Japanese spotted a small American convoy that consisted of a
fleet tug towing a gasoline
barge and escorted by the destroyer . Aircraft from
Shōkaku and
Zuikaku sank the latter, but did not attack the tug. The Japanese and American carrier forces discovered each other in the early morning of 26 October and each side launched air strikes.
Shōkaku was badly damaged by six hits from 's dive bombers;
Zuikaku was not spotted or attacked as she was hidden by the overcast conditions, just like at the Battle of the Coral Sea. In exchange, the Japanese crippled
Hornet with two torpedoes and three bombs. In addition, two aircraft crashed into the American carrier and inflicted serious damage.
Enterprise was also damaged by two bomb hits and a near miss and a destroyer was damaged when it was struck by a B5N. Attacks later in the day further damaged
Hornet, which was abandoned and later sunk by Japanese destroyers and . The Japanese lost nearly half their aircraft that participated in the battle, together with their irreplaceable experienced aircrew. On 2 November, the First Carrier Division was ordered home for repairs and training.
Shōkakus repairs continued until March 1943 and
Zuikaku, together with the recently repaired
Zuihō, sailed for Truk on 17 January to support the impending evacuation of Japanese ground forces from Guadalcanal (
Operation Ke). On 29 January, the two carriers flew off 47 Zeros to Rabaul and
Kahili Airfield, contributing some of their own aircraft and pilots.
Zuihō was then used to cover the evacuation, while
Zuikaku remained at Truk, together with the two
Yamato-class battleships, acting as a
fleet in being threatening to sortie at any time. In May,
Shōkaku and
Zuikaku were assigned to a mission to counterattack the
American offensive in the
Aleutian Islands, but this operation was cancelled after the Allied victory on
Attu on 29 May. The sisters were transferred to Truk in July. In response to the carrier raid on
Tarawa on 18 September, the carriers and much of the fleet sortied for
Eniwetok to search for the American forces before they returned to Truk on 23 September, having failed to locate them. The Japanese had intercepted some American radio traffic that suggested another attack on
Wake Island, and on 17 October,
Shōkaku and
Zuikaku and the bulk of the 1st Fleet sailed for Eniwetok to be in a position to intercept any such attack, but no attack occurred and the fleet returned to Truk. At the beginning of November, the bulk of their air groups were transferred to Rabaul to bolster the defenses there, just in time to help defend the port against the
Allied attack a few days later. They accomplished little there, for the loss of over half their number, before returning to Truk on the 13th. The sisters returned to Japan in December. The First Carrier Division sailed in mid-May for
Tawi-Tawi in the Philippines.
Battle of the Philippine Sea The
1st Mobile Fleet was en route to
Guimaras Island in the central Philippines on 13 June, where they intended to practice carrier operations in an area better protected from submarines, when
Vice Admiral Jisaburō Ozawa learned of the American attack on the
Mariana Islands the previous day. Upon reaching Guimares, the fleet refueled and sortied into the
Philippine Sea where they spotted
Task Force 58 on 18 June. At this time, the sister ships mustered 54 Zeros, 60 D4Ys and 36
Nakajima B6N "Jill" torpedo bombers. As the carriers were launching their first airstrike the following morning,
Taihō was torpedoed by an American submarine and later sank. Later that morning,
Shōkaku was torpedoed by a different submarine, . The three or four torpedoes started multiple fires in the hangar, which ignited fueling aircraft, in addition to causing heavy flooding. As the bow continued to sink, aircraft and munitions began to slide forward and a bomb in the hangar detonated. This ignited gas and oil fumes which caused a series of four explosions that gutted the ship.
Shōkaku sank several minutes later with the loss of 1,263 of her crew. 570 men were rescued by a light cruiser and a destroyer. The loss of
Taihō and
Shōkaku left
Zuikaku to recover the Division's few remaining aircraft after their heavy losses (only 102 aircraft remained aboard the seven surviving carriers by the evening) and the 1st Mobile Fleet continued its withdrawal towards
Okinawa. The Americans did not spot the Japanese carriers until the afternoon of the following day and launched a large airstrike that only succeeded in hitting
Zuikaku with a single bomb that started a fire in the hangar. At this time, the ship had 28 A6M5 Zero fighters, 16 A6M2 Zero
fighter-bombers, 7 D4Y reconnaissance aircraft and 15 B6Ns. On the morning of 24 October, she launched 10 fighters, 11 fighter-bombers, 6 torpedo bombers, and 2 reconnaissance aircraft The American carriers launched an airstrike shortly after dawn;
Zuikaku was struck by three bombs and one torpedo that started fires in both hangars, damaged one
propeller shaft, and gave her a 29.5°
list to port. Fifteen minutes later, the fires were extinguished and the list was reduced to 6° by counterflooding. She was mostly ignored by the second wave of attacking aircraft, but was a focus of the third wave that hit her with six more torpedoes and four bombs. The bombs started fires in the hangars, the torpedoes caused major flooding that increased her list, and the order to abandon ship was issued before
Zuikaku sank by the stern. Lost with the ship were 49 officers and 794 crewmen, but 47 officers and 815 crewmen were rescued by her escorting destroyers. ==Notes==