Battle of the Coral Sea
Date of battleMay 4 - May 8, 1942
ConflictSecond World War
Battle beforeThe Doolittle Raid
Battle afterBattle of Midway
Site of battleCoral Sea, between Australia,
New Guinea, and the Solomon Islands
Combatant 1USA and Australia
CommandersRear Admiral Frank Jack Fletcher
Strength2 large carriers, 3 cruisers
Combatant 2Japan
CommandersVice Admiral Shigeyoshi Inoue
Strength2 large carriers, 1 small carrier, 4 cruisers
ResultTactical Japanese victory,
strategic Allied victory
Casualties(1): 540
(2): 3,500

The Battle of the Coral Sea, in early May 1942, was the first major aircraft carrier engagement of the Second World War, and one of the half-dozen most significant battles of the Pacific war. It was also the first naval battle to take place at long distance: neither side's surface fleet sighted the other.

Table of contents
1 Background
2 The battle
3 Significance
4 References
5 Order of Battle

Background

Having conquered nearly all of Southeast Asia in just a few months, Japan was at the apex of its power. Still reeling from a long series of humiliating defeats, the Allies were just beginning to develop the skills and organise the materiel assets needed to survive and, eventually, strike back. Allied strategy at this time was focused on a defensive build-up of United States Army and Marine strength on New Caledonia (well to the south of the Solomon Islands), and Australian air and ground strength at Port Moresby (in southern New Guinea, just north of the Australian mainland).

In April 1942, Japanese forces left their stronghold of Rabaul (on New Britain, just north of New Guinea) and launched a two-pronged amphibious invasion of Port Moresby (Operation MO), and Tulagi in the Solomon Islands. The intention was threefold: to establish control of the Solomons, initially with a seaplane base; to destroy and then occupy Port Morseby (the last Allied base between Japan and Australia); and in doing these things, to bring the American aircraft carrier fleet to battle for the first time in the war. Historians remain divided about Japanese longer-term intentions: there seems little doubt that they planned to greatly strengthen their hold on the Solomon Islands as a bastion against any future US counter attacks, a reasonable probability that northern Australia would be invaded, and considerable doubt about the following moves, if any. In practice, Japanese military planning structure was complex, had ill-defined areas of responsibility, and was crippled by endless bitter debates between army and navy. The only firm deduction that can be made about longer-term Japanese plans in the South Pacific is that whatever the navy eventually put forward would be opposed by the army with a counter-plan!

Three Japanese fleets set sail: the invasion forces for the Solomons and Port Moresby, and a covering force consisting of two big new aircraft carriers (Shokaku and Zuikaku, both Pearl Harbor veterans), a smaller carrier (Shoho), two heavy cruisers, and supporting craft. Alerted by radio intercepts, the Allies knew that Japanese land-based aircraft were being moved south and that an operation was impending. In opposition, they had three main fleets: USS Yorktown (CV-5) already in the Coral Sea under the command of Admiral Frank Jack Fletcher, USS Lexington (CV-2) en route, and a joint Allied surface fleet. The carriers USS Hornet (CV-8) and USS Enterprise (CV-6) were heading south after the Doolittle Raid on Tokyo but arrived too late to take part in the battle.

The battle

Lexington arrived to join Yorktown on May 1st. The Japanese occupied Tulagi without incident on May 3rd, and construction of a seaplane base started. After fuelling, Yorktown closed on Tulagi and, on May 4, launched three successful strikes against Japanese shipping and aircraft there - revealing the presence of an American carrier to the enemy but sinking the destroyer Mikazuki, crippling the island's floatplane reconnaissance capability, and damaging other vessels before retiring to the south to rendezvous with Lexington and the newly-arrived cruisers. Meanwhile, the two large Japanese carriers were approaching from south of the Solomons - neatly placing the Allied fleet between the two Japanese fleets.

Land-based B-17s attacked the gradually approaching Port Moresby invasion fleet on May 6 with the usual lack of success. (Almost another year would pass before air forces realised that high-level bombing raids on moving naval targets were pointless.) Although both carrier fleets flew extensive searches on the 6th, cloudy weather kept them hidden from each other and the two fleets spent the night only 70 miles apart.

On the 7th, both fleets flew off all available aircraft, but neither found the main body of the other, and both mistakenly attacked subsidiary forces. Japanese aircraft found the US fleet oiler USS Neosho (AO-23) and escorting destroyer USS Sims (DD-409); mistaking them for a carrier and a cruiser, they attacked and sank both. Meanwhile, the US aircraft had missed Shokaku and Zuikaku but found the invasion fleet, in company with the small carrier Shoho, which was soon sunk. In the previous five months, the Allies had lost a dozen battleships and carriers and been unable to sink a single major Japanese unit in return. Shoho was small by carrier standards, but the laconic "scratch one flattop" radioed back to Lexington brought news of the first Allied naval success of the Pacific war.

That night Fletcher, mindful that his primary role was to protect Port Moresby, took the tough decision to detach his surface fleet (cruisers HMAS Australia, USS Chicago (CA-29), HMAS Hobart, and two American destroyers) to block the progress of the invasion fleet toward Port Moresby, knowing that exposing surface ships to attack by land-based aircraft without air cover was to risk the same fate that had overtaken British battleships HMS Prince of Wales and HMS Repulse five months before.

Finally, with dawn searches on May 8, the main carrier forces located one another and launched maximum effort raids, which passed each other in the air. Hidden by rain, Zuikaku escaped detection, but Shokaku was hit three times by bombs. Listing and on fire, Shokaku was unable to land her aircraft and effectively out of action.

Both American carriers were hit by the Japanese strike: Yorktown by a bomb, the larger, less manoeuvrable Lexington by both bombs and torpedoes. Although she survived the immediate damage and was thought to be repairable, leaking aviation fuel exploded a little over an hour later: Lexington had to be abandoned and torpedoed to prevent capture.

While the carrier task forces were battling, the Allied surface force had approached within range of land-based aircraft from Rabaul. It was attacked repeatedly through the day by Japanese bombers and once (mistakenly) by American B-17s, but survived intact and continued to stand between the invasion force and Port Moresby. Misled as to the strength of the surface force by returning fliers' reports, Japanese Admiral Inouye (in overall command of the operation from Rabaul) ordered the invasion fleet to return. With Shokaku damaged and Zuikaku short on aircraft, neither was able to take part in the crucial Battle of Midway a month later. Yorktown returned to Pearl Harbor.

Significance

References

Order of Battle

Japanese Forces

Task Force "MO"
  • Carrier Striking Force - Vice Admiral Takeo Takagi
    • Shokaku
    • Zuikaku
    • Myoko
    • Kaguro
    • destroyers (div 7) Ushio, Akebono
    • destroyers (div 27) Ariake, Yogure, Shiratsuyu, Shigure
    • oiler Toho Maru
  • Tulagi Invasion Group - Rear Admiral Kiyohide Shima
    • minelayers Okinoshima (sunk), Koei Maru
    • transport Azumasan Maru
    • destroyers Kikuzuki (sunk), Yuzuki
    • (need smaller vessels)
  • Port Moresby Invasion Group - Rear Admiral Sadamichi Kajioka
    • Yubari
    • destroyers Oite, Asanagi, Uzuki, Mutsuki, Mochizuki, Yayoi
    • Transport Unit - Rear Admiral Koso Abe
  • Support Group - Rear Admiral Kuninori Marumo
    • Tenryu
    • Tatsuta
    • Kamikawa Maru
    • gunboats Keijo Maru, Seikai Maru, Nikkai Maru
  • Covering Group - Rear Admiral Goto
    • Aoba
    • Kako
    • Kinugasa
    • Furutaka
    • Shoho (sunk)
    • Sazanami
  • Submarine Force - Captain Noburu Ishizaki

Allied Forces

Task Force 17 - Rear Admiral Frank Jack Fletcher