"Australia and New Zealand are now threatened by the might of the Imperial forces and both them should know that any resistance is futile. If the Australian government does not modify her present attitude their continent will suffer the same fate as the Dutch East Indies." - Hideki Tojo, Japanese Prime Minister, 12 March 1942.

I.  Introduction

By the Spring of 1942, the Japanese have taken the Philippines, Malaysia, and the Dutch East Indies. Australia is virtually defenseless. Her four all volunteer divisions are engaged in North Africa and Malaysia. Britain is expelled from her colonies and the main Allied supply line extends across the Pacific from America to Australia and New Zealand.

Japan's military planners are split over the need to invade Northern Australia or simply isolate Australia and engage the American fleet. The Doolittle raid against mainland Japan crystallizes in the minds of the high command the need to neutralize the American aircraft carriers. To isolate Australia and draw the American fleet into battle the Japanese commanders approve a three prong operation.

1. Occupy Tulagi in the southern Solomon Islands in order to establish a naval air base to control the northern part of the Coral Sea. Follow this with a landing at Port Moresby in southeast New Guinea so as to bring Northern Australia in to range of Japanese aircraft. This stage of the plan is "Operation MO" so called because the first two letters of the Japanese name for Port Moresby are MO.

2. Carry out an overwhelming attack on Midway and occupy strategic points in the Aleutian Islands to trigger a decisive naval battle.

3. Once these two operations are complete the Japanese will overrun the Fiji and Samoan Islands in order to cut off the life line from the United States to Australia.

The bulk of the Imperial Japanese Navy (IJN) fleet is to be used in the Midway and Aleutian Island operations. Vessels used in Operation MO are expected to join with the Midway operation forces.

The threat to Australia's supply line from North America is confirmed by American cryptologists, who are able to read bits and pieces of the IJN JN-25 naval code. With this intelligence, Admiral Nimitz, Commander in Chief of the Pacific Fleet (CINCPAC), orders three task forces, TF17, TF11 and TF44 to join and oppose the IJN operations.

II.  Organization of Forces

A. IJN forces.

The main elements of the IJN force are the Covering Forces and the Striking Forces for the invasions of Tulagi and Port Moresby. Task force, task group or task unit designations are not used by the IJN as does the U.S. Navy. Instead, they use the ideograph "Tai" and sometimes "Butai," which could be any group of ships except for "Combined Fleet," which are "Rengo Kantai." "Tai" is usually translated as "force" or "body."

Carrier Striking Force Rear Admiral Takagi Carriers Shokaku and Zuikaku (IJN's newest carriers) Heavy cruisers Myoko and Haguro Destroyers Ariake, Yugure, Shigure, Shiratsuyu, Ushio and Akebono Tanker Toho Maru

Port Moresby Landing Force Transport Force Rear Admiral Abe Minelayer Tsugaru, twelve transports, and auxiliary craft. Attack Force Rear Admiral Kajioka Light cruiser Yubari; Destroyers Oite, Uzuki, Asamagi, Mutsuki, Yunagi and Yayoi. One patrol boat and auxiliary craft Close Support Force Rear Admiral Goto Light carrier Shoho; Destroyer Sazanami Support Force Main Body Rear Admiral Goto Heavy cruisers Aoba, Kako, Kinugasa, and Furutaka Close Cover Force Rear Admiral Marumo Light cruisers Tenryu and Tatsuta; Seaplane Tender Kamikawa Maru; Gunboats Keijo Maru, Seikai Maru and Nikkai Maru; Minelayer Tsugaru

Tulagi Landing Force Rear Admiral Shima Destroyers Kaikuzuki and Yuzuki; Minelayers Okinoshima, Koei Maru; Transport Asuman Maru and auxiliary craft

B. USN forces.

Task Force 17 (TF17) Rear Admiral Frank J. Fletcher In Yorktown (CV-5)

Task Group 17.2 (Attack Group) Admiral Thomas C. Kinkaid Cruisers Minneapolis (CA-36), New Orleans (CA-32), Astoria (CA-34), Chester (CA-27) and Portland (CA-33); Destroyers Phelps (DD-360), Dewey (DD-349), Farragut (DD-348), Aylwin (DD-355) and Monaghan (DD-354)

Task Group 17.5 (Carrier Group) Rear Admiral Aubrey W. Fitch Carrier Yorktown (CV-5), Carrier Lexington (CV-2) formerly (TF11) joined with Yorktown on 1 May 1942. Destroyers Morris (DD-417), Anderson (DD-411), Hammann (DD-412) and Russell (DD-414)

Task Group 17.3 (Support Group) Rear Admiral J. C. Crace, RAN Cruisers Australia (RAN), Hobart (RAN) and Chicago (CA-29); Destroyers Perkins(DD-377) and Walke (DD-416). Joined TF17 on 1 May 1942, formerly TF44.

Task Group 17.6 (Fueling Group) Captain John S. Philllips Oilers Neosho (AO-23) and Tippecanoe (AO-21); Destroyers Sims (DD-409) and Worden (DD-352)

Task Force 16, consisting of the carriers Hornet (CV-8) and Enterprise (CV-6), under Rear Admiral Halsey, are unavailable while engaged in delivering Colonel Doolittle, and his Mitchell B-25's to the raid on mainland Japan.

III.  Chronology
 

1-3 May 1942

TF-17 refuels from Neosho (AO-23).

4 May 1942

Action begins on 4 May with a dawn strike on Tulagi by the carrier Yorktown's Air Group Five (VF-42, VB-5, VS-5 and VT-5). At 0630 Yorktown launches 11 TBD-1 Douglas Devastator torpedo aircraft and 28 SBD Douglas Dauntless dive bombers. Six F4F Grumman Wildcat fighters follow the strike aircraft and 18 fighters are retained in defense of the force. The SBD dive bombers of VB-5 surprise the IJN and damage the destroyer Kikusuki and two mine sweepers. The TBD-1 torpedo aircraft (VT-5) arrive second and score one hit on the mine sweeper Tara Maru from eleven torpedoes fired. All aircraft from the first strike return and are safely recovered. A second strike is launched to Tulagi as soon as the returned aircraft are refueled and rearmed.   This time 27 Dauntless dive bombers and 11 Devastator torpedo planes make the trip.  The second strike yields one patrol boat damaged and two seaplanes destroyed on the water.  The Japanese are alert and destroy one TBD-1 Devastator by anti aircraft fire. In the early afternoon a third raid is launched consisting of four F4F Grumman Wildcats.  Three moored seaplanes are destroyed and the destroyer Yuzuki is strafed killing the ship's captain and others but not disabling the ship.  Two Wildcats are hit and make forced landings on the south coast of Guadalcanal.  Both pilots are rescued by the destroyer Hammann (DD-412).   A fourth strike is ordered by Admiral Fletcher consisting of 21 SBD Dauntless dive bombers which succeeds in destroying several landing craft. Debriefings after the four strikes convince Admiral Fletcher that little has been accomplished even though the enthused American pilots report spectacular successes.  Consideration is given to ordering surface strikes by the heavy cruisers Chester (CA-27) and Astoria (CA-34), but cancelled when General McArthur's Headquarters in Australia reports B-25 Mitchell bombers have located Admiral Goto's force south of Bougainville.

5 May 1942

Admiral Takagi's IJN Striking Force enters the Coral Sea while Rear Admiral Fletcher sails northwest toward the probable route of the IJN Port Moresby Landing Force. Neither admiral has any idea as to the size or position of his opponent's fleet. At 0815 the Lexington and Yorktown task groups join.  Yorktown's radar detects an unidentified aircraft at 1100 but due to low visibility American fighters are unable to make visual contact with the enemy aircraft.  For the first time in the Pacific Theater an American fighter is vectored by the ship's radar to intercept and destroy an aircraft.  The H6K Kawaniski Mavis four engine seaplane is from Rabaul and not under the command of the nearby Japanese naval force, and therefore does not report the American presence to the nearby afloat IJN forces.

6 May 1942

Both fleets close to within seventy miles of each other yet are unaware of the other's position as weather hinders their reconnaissance planes. Refueling is the order of the days for both forces.  Admiral Goto's force is attacked by Army B-17's from Australia.  The Flying Fortresses drop twelve bombs near the carrier Shoho but are driven off by A6M Mitsubishi Zeke's (Zero).

7 May 1942

Based on incorrect reconnaissance reports, both admirals launch major air attacks. Takagi sends a large force to the south-southeast, where the tanker Neosho (AO-23) and the destroyer Sims (DD-409) are mistakenly identified as a carrier and a cruiser. Both American ships are lost. Admiral Fletcher orders a major strike against what is mistakenly reported as two carriers and finds instead Admiral Goto's Covering Force protecting the Port Moresby invasion force. American aircraft attack the light carrier Shoho, which is sunk by numerous bomb and torpedo hits. This prompts Lieutenant Commander Bob Dixon, of Lexington's VS-2 to radio the famous message, "Scratch one flattop!" This is the first attack by American carrier aircraft against a capital ship, and the first carrier to be lost by either side. During this action, the first IJN A6M Mitsubishi Zeke (Zero) fighter to be downed by a Navy or Marine Corps aviator is shot down by Lieutenant Junior Grade Walt Haas of VF-42 from Yorktown. In late afternoon, Takagi launches twenty-seven bombers from his two big carriers, but finding nothing they jettison their bombs and torpedoes. Their course back takes them over Fletcher's force. The USN ships fire on the IJN bombers and F4F Wildcats attack the enemy aircraft inflicting heavy losses. Some reports state that confused Japanese pilots actually try to land on the American carrier.

8 May 1942

The climax of the battle on the 8 May finds the IJN invasion fleet has retired to let the carrier forces battle it out. The opposing forces are fairly evenly matched with two carriers and approximately 20 aircraft each. Scout planes from both forces locate the enemy at about 0820 local time and approximately 200 miles apart. American Attack At 1057, American dive and torpedo bombers attack the Shokaku finding twin problems in defending Zero's and bad weather. After numerous near misses, the Dauntless dive bombers score a hit with a 1000 pound bomb. VB-5 pilot, Lieutenant John Powers, with his plane on fire, hits the Shokaku with another 1000 pound bomb causing extensive damage and fires. Lieutenant Powers does not recover from his dive and is awarded a posthumous Medal of Honor for his bravery. A third SBD from the Lexington hits the Shokaku with a 1000 pound bomb. At this point the badly damaged Shokaku transfers her aircraft to the Zuikaku and retires to the north. The Zuikaku safely hides in a rainstorm throughout the action and is not touched by the American attack. Japanese Attack A search plane from the Shokaku, hiding in the clouds, shadows the Americans and later guides the IJN strike group to within sight of the Lexington. Fourteen IJN torpedo planes execute an attack on Lexington.  Demonstrating their seasoned tactics, the IJN torpedo bomber pilots attack with two simultaneous thrusts from 45 degrees either side of the bow. Lexington tries to dodge the torpedoes, but at 1120 she receives two hits. Attacks on the Yorktown by four torpedo planes come close, but she receives no hits. Japanese dive bombers push over in steep attack formations a few minutes after the torpedo attack. The F4F Wildcat's of the Combat Air Patrol (CAP) fight to stop them, but find themselves engaged in furious dogfights with the escorting Zeros. The Lexington suffers two bomb hits and numerous near misses. Dive bombers from the Zuikaku attack the Yorktown at 1142. They are harassed all the way down by two F4F's from VF-42.  The Yorktown is steaming crosswind at full speed and skillfully avoids all but one direct hit. This 250 kg bomb strikes the center of Yorktown's flight deck forward of the middle elevator.  Several near misses cause underwater damage. Throughout all the action there are numerous dogfights. Once the IJN attackers retire, the U.S. carriers are still able to steam at 24 knots and recover aircraft despite their damage. But trouble is developing aboard the Lexington. Leaking gasoline results in a tremendous explosion at 1247, killing 25 men. She is able to recover her strike group, but is wracked by two more explosions.  The situation rapidly deteriorates. In short order Lexington experiences crippled communications, loss of helm control from the bridge, smoke drawn in by blowers putting out her boiler fires and forcing the boiler room personnel to evacuate, low fire main pressure, more fires and explosions until she is dead in the water and helpless. Consideration is given to towing the Lexington with one of the cruisers, but in view of her severe damage and the possibility of another air attack, the decision is made to abandon ship at 1707. This is done in nearly ideal conditions and 92% of Lexington's complement is picked up by friendly ships. Later, with the Lexington burning furiously, the destroyer Phelps (DD-360) sends five torpedoes into "Lady Lex" and she sinks at 1952 with final tremendous underwater explosions. After this day's battles, both fleets retire. The Japanese postpone their invasion of Port Moresby and suffer the first major strategic setback of the war.

IV.  Results and Conclusions

At first glance it would appear that the battle was a Japanese victory or a draw at best, since they lost but a small carrier and the U.S. a large one. But strategically, the outcome was unquestionable an American Navy victory.

Most importantly, it stops the Japanese advance southward, and possibly saves Australia from invasion. Secondly, Japan's newest large carriers, the Shokaku and the Zuikaku are prevented from participating in the Battle of Midway.  Shokaku is heavily damaged and must return to Japan for major repairs remaining out of service for three months. The Zuikaku, although undamaged, has suffered major losses to her air group and also returns to Japan.  She is out of action for two months while replacement pilots are trained. Thus both these new carriers are unavailable for the Battle of Midway. It is conceivable that their presence at Midway would have spared the IJN from their staggering defeat with the loss of four carriers.

U.S. Navy lessons learned at Coral Sea.
 

Aircraft:

(1) The F4F could defeat Zero if they attacked with an altitude advantage.      (2) Wildcats should not try to out turn the more maneuverable Zeros.      (3) Fighters need to stay together for mutual protection.      (4) Fighters required belly tanks for more range.      (5) Better CAP (carrier air patrol) and fighter direction procedures were essential.      (6) Torpedo planes and bombers have to be escorted.      (7) IFF (identification friend or foe) transponders on all aircraft was sorely needed.      (8) Communications equipment desperately needed improvement.

Shipboard:

(1) Fire fighting training was necessary to save ships.      (2) Damage control equipment improvements were needed.

The list is long and the Battle of Midway would be in less than a month, long before many of the lessons could be implemented.

The Battle of Coral Sea marks the first time in the history of naval warfare that opposing ships are never in sight of each other, and no shots are exchanged.  The battle is fought entirely by carrier planes. It ushers in a new era in the history of naval warfare - the supremacy of the aircraft carrier.

Disclaimer : References vary on the IJN order of battle. 

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