The Battle of the Coral Sea, fought in the waters southwest of the Solomon Islands and eastward from New Guinea, was the first of the Pacific War's six fights between opposing aircraft carrier forces. Though the Japanese could rightly claim a tactical victory on "points", it was an operational and strategic defeat for them, the first major check on the great offensive they had begun five months earlier at Pearl Harbor. The diversion of Japanese resources represented by the Coral Sea battle would also have immense consequences a month later, at the Battle of Midway.

The Coral Sea action resulted from a Japanese amphibious operation intended to capture Port Moresby, located on New Guinea's southeastern coast. A Japanese air base there would threaten northeastern Australia and support plans for further expansion into the South Pacific, possibly helping to drive Australia out of the war and certainly enhancing the strategic defenses of Japan's newly-enlarged oceanic empire.

The Japanese operation included two seaborne invasion forces, a minor one targeting Tulagi, in the Southern Solomons, and the main one aimed at Port Moresby. These would be supported by land-based airpower from bases to the north and by two naval forces containing a small aircraft carrier, several cruisers, seaplane tenders and gunboats. More distant cover would be provided by the big aircraft carriers Shokaku and Zuikaku with their escorting cruisers and destroyers. The U.S. Navy, tipped off to the enemy plans by superior communications intelligence, countered with two of its own carriers, plus cruisers (including two from the Australian Navy), destroyers, submarines, land-based bombers and patrol seaplanes.

Preliminary operations on 3-6 May and two days of active carrier combat on 7-8 May cost the United States one aircraft carrier, a destroyer and one of its very valuable fleet oilers, plus damage to the second carrier. However, the Japanese were forced to cancel their Port Moresby seaborne invasion. In the fighting, they lost a light carrier, a destroyer and some smaller ships. Shokaku received serious bomb damage and Zuikaku's air group was badly depleted. Most importantly, those two carriers were eliminated from the upcoming Midway operation, contributing by their absence to that terrible Japanese defeat.

Preliminary Activities
Good communications intelligence allowed the U.S. Pacific Fleet to prepare to meet the planned Japanese offensive against Port Moresby, though available resources provided little margin for error. The freshly overhauled carrier Lexington (CV-2), rushed out from Pearl Harbor, joined USS Yorktown in the probable action area on 1 May, doubling Rear Admiral Frank Jack Fletcher's carrier forces and bringing along another experienced flag officer, Rear Admiral Aubrey W. Fitch. These carriers and their consorts engaged in several days of refueling from the oilers Neosho (AO-23)and Tippecanoe (AO-21), while awaiting the arrival of two Australian cruisers to reinforce the six already on hand.

On 3 May a small Japanese naval force carried out a landing at Tulagi, on the northern side of the Coral Sea, where they quickly established a seaplane base to provide reconnaissance deeper into Allied waters. Leaving Lexington behind and detaching Neosho to join her, Rear Admiral Fletcher took Yorktown off to interfere with the landings. On the morning of the 4th, his planes hit the invasion force. Though results were modest, to some extent due to humid air fogging the dive bombers' sights, the destroyer Kikuzuki was fatally damaged and a few other ships and seaplanes were sunk.

Fletcher then turned back south, rejoining Fitch on the 5th to top off his fuel tanks. The Japanese were now advancing into the Coral Sea with the Port Moresby Invasion Force and the separate Covering Force and aircraft carrier Striking Force. Both the American and Japanese carrier commanders spent the 6th moving westward, unaware just how close they had come -- at one point they were but 70 miles apart!

The Events of 7 May 1942
The first day of the carrier battle of Coral Sea, 7 May 1942, saw the Americans searching for carriers they knew were present and the Japanese looking for ones they feared might be in the area. The opposing commanders, U.S. Rear Admiral Frank Jack Fletcher and Japanese Vice Admiral Takeo Takagi and Rear Admiral Tadaichi Hara, endeavored to "get in the first blow", a presumed prerequisite to victory (and to survival) in a battle between heavily-armed and lightly-protected aircraft carriers. However, both sides suffered from inadequate work by their scouts and launched massive air strikes against greatly inferior secondary targets, which were duly sunk, leaving the most important enemy forces unhit.

Japanese scouting planes spotted the U.S. oiler Neosho (AO-23) and her escort, the destroyer USS Sims (DD-409), before 8AM, in a southerly position well away from Admiral Fletcher's carriers. Reported as a "carrier and a cruiser", these two ships received two high-level bombing attacks during the morning that, as would become typical of such tactics, missed. However, about noon a large force of dive bombers appeared. As was normal for that type of attack, these did not miss. Sims sank with very heavy casualties and Neosho was reduced to a drifting wreck whose survivors were not rescued for days.

Meanwhile, a scout plane from USS Yorktown (CV-5) found the Japanese Covering Group, the light carrier Shoho and four heavy cruisers, which faulty message coding transformed into "two carriers and four heavy cruisers". Yorktown and USS Lexington (CV-2) sent out a huge strike: fifty-three scout-bombers, twenty-two torpedo planes and eighteen fighters. In well-delivered attacks before noon, these simply overwhelmed the Shoho, which received so many bomb and torpedo hits that she sank in minutes. Her passing was marked by some of the War's most dramatic photography.

Adding to the confusion, if not to the score, Japanese land-based torpedo planes and bombers struck an advanced force of Australian and U.S. Navy cruisers, far to the west of Admiral Fletcher's carriers. Skillful ship-handling prevented any damage. Australia-based U.S. Army B-17s also arrived and dropped their bombs, fortunately without hitting anything.

All this had one beneficial effect: the Japanese ordered their Port Moresby invasion force to turn back to await developments. Late in the day, they also sent out nearly thirty carrier planes to search for Fletcher's ships. Most of these were shot down or lost in night landing attempts, significantly reducing Japanese striking power. The opposing carrier forces, quite close together by the standards of air warfare, prepared to resume battle in the morning.

Events of 8 May 1942
Before dawn on 8 May, both the Japanese and the American carriers sent out scouts to locate their opponents. These made contact a few hours later, by which time the Japanese already had their strike planes in the air. The U.S. carriers launched theirs' soon after 9AM, and task force commander Rear Admiral Frank Jack Fletcher turned over tactical command to Rear Admiral Aubrey W. Fitch, who had more carrier experience. Each side's planes attacked the other's ships at about 11AM. At that time the Japanese were partially concealed by thick weather, while the Americans were operating under clear skies.

Planes from USS Yorktown hit the Shokaku, followed somewhat later by part of USS Lexington's air group. These attacks left Shokaku unable to launch planes, and she left the area soon after to return to Japan for repairs. Her sister ship, Zuikaku, was steaming nearby under low clouds and was not molested.

The Japanese struck the American carriers shortly after Eleven, and, in a fast and violent action, scored with torpedoes on Lexington and with bombs on both carriers. For about an hour, Lexington seemed to have shrugged off her damages, but the situation then deteriorated as fires spread through the ship. She was abandoned later in the day and scuttled. Yorktown was also badly damaged by a bomb and several near misses, but remained in operational condition.

By the end of the day, both sides had retired from the immediate battle area. The Japanese sent Zuikaku back for a few days, even though her aircraft complement was badly depleted, but they had already called off their Port Moresby amphibious operation and withdrew the carrier on May 11th. At about the same time USS Yorktown was recalled to Pearl Harbor. After receiving quick repairs, she would play a vital role in the in early June.