Scratch One Flattop-The Battle of Coral Sea

While the hit and run carrier raids of February and March tested American carrier doctrine to an extent, and the Pearl Harbor raid as well as Indian Ocean raids tested Imperial Navy doctrine also to an extent, this is the very first time that both navies tested each other’s way of doing things, and in the process found things that worked, and things that well…didn’t work.  Let’s dig into it…

Talking Points:

• What sets off the battle of Coral Sea?

o Outline Japanese plans for Operation MO

 Japanese wanted to seize Port Moresby and all of New Guinea.  By doing this, it would provide Japan with both a way to isolate Australia as well as New Zealand from allied supply lines, specifically American supply lines.  

• Why Rabaul (Opeation R) wasn’t good enough

 This was to be prefaced by the Japanese capture of Tulagi, which is an island we will hear a lot about in the near future.  By capturing Tulagi, in the Solomons, the Japanese could patrol the area and the sea lanes to Port Moresby so as to allow their invasion force a free hand.

 As part of the Port Moresby invasion attempt, the invasion group was to be covered by two separate carrier groups, one which centered around the light carrier Shoho, and another which centered around the fleet carriers Shokaku and Zuikaku.

o US intel at Station HYPO and fleet radio unit Melbourne, or FRUMEL decrypt Japanese messages to an extent, and in turn believe that the Japanese will strike the area of Port Moresby, or the northern coast of Australia on or about the first week of May.

 As a result of this intel, Nimitz deploys the only two carrier task forces at his disposal at this time, those centered around USS Lexington, and USS Yorktown, TF 11 and TF 17 respectively, to stand by the area of the Coral Sea with designs to intercept and destroy the incoming Japanese invasion and support fleets.

• On May 1 the two US CV TFs unite under the command of ADM Fletcher

o May 4, Fletcher detaches CV5 to attack recent Japanese positions on Tulagi

 CV5’s attacks are relatively successful, with damage inflicted on enemy positions and shipping in and around the harbor of Tulagi

• US losses are minimal

• By May 6, Fletcher is aware that Japanese CVs are in the area, and the Japanese invasion fleet is not far behind.  As a result, he detaches ADM Crace’s cruisers WITHOUT air cover to block the invasion force.

o This is potentially a critical blunder by Fletcher.  Crace’s CAs could have been blown out of the water by Japanese CVs, as it was, they were attacked three times by Japanese aircraft and once by MacArthur’s B17s.  

 Japanese reports stated that they had sunk a BB, damaged a second BB and a CA.  Japanese sent no further attacks towards Crace.  His vessels survived due to poor Japanese (and American) accuracy as well as his skillful maneuvering.  

 The sighting of the supposed BBs by the Japanese informed the invasion fleet to reverse course

 Still a horrible decision by Fletcher

• First day of the carrier battle May 7

• Early on the morning of the 7th, Japanese launch searches to find US CVs

o Japanese scout planes from Shokaku find US ships and radio ADM Tagaki of 1 CV, 1 CA, and 3 DD.

 What the Japanese actually sight is the detached oiler Neosho and her escort DD Sims.  

• How did the Japanese pilot screw this up this bad?

• Japanese arrive over oiler and DD, realize their mistake and continue their search, they return and attack and sink Sims and force Neosho to be abandonned

• At 0815 a CV5 SBD piloted by John Nielsen finds the Japanese screening force under ADM Goto, which includes light carrier Shoho.  

o An error in Nielsen’s coding made the message read 2 Japanese CVs instead of 1.

• Fletcher loses his mind on Nielsen when he lands and clarifies his message

 Believing this to be the main Japanese CV force, Fletcher launches everything he has.  

• 93 aircraft are flung at Shoho

o 18 F4Fs, 53 SBDs, 22 TBDs from CV2 and CV5

• Lexington Air Group, under Bill Ault arrive over Shoho first

o The SBDs attack first, and score at least 2 bomb hits and the TBDs score 5 torpedo hits

 This is the only real successful TBD attack of WW2

• Lex AG executes a hammer and anvil attack and leave Shoho a wreck

 Talk about Walt Nelson and Ted Wiebe

• Yorktown Air Group arrive next and continue to pummel Shoho.

o Estimated 11 bombs and 2 more torpedoes

o She is barely afloat as US aircraft leave and is gone by 1135

• Lexington VB2 CO, Bob Dixon sent a prearranged radio signal back to Fletcher that simply said, “Scratch One Flattop”

• Second day of the carrier battle May 8

• Both Japanese and US locate each other almost simultaneously

o US launch first at 0900, Japanese at 0915

 Opposing forces actually pass each other on the way to their targets

• US attack Japanese first

o The well-coordinated attack of May 7 gives way to the mess of May 8

 US aircraft have trouble finding the targets due to squally weather

• When they do find them, they can’t coordinate their attacks as the previous day

 Yorktown aircraft under Bill Burch find and attack Shokaku.

• The ship is moving radically but is still hit with 2 1,000 pound bombs which puts her flight deck out of action.

• Lex Air Group attacks and half of her SBDs find Shokaku and attack, hitting her once, the other half of the attackers from Lex can’t find the ship.

• All TBD torpedo attacks by both Air Groups miss their targets or the weapons fail to explode

• Japanese attack on US fleet

• Enemy is picked up 68 nautical miles away by US radar

o Poorly executed fighter direction operations positioned the US CAP too low to intercept the incoming enemy strike.

• One of the stranger aspects of Coral Sea is that SBDs were utilized as anti-torpedo plane CAP

o The assumption was that the Japanese Kate was as slow and sluggish as the TBD, which was obviously false

 One of the anti-VT pilots was Swede Vejtasa

• Talk about Swede’s dogfight against Zuikaku aircraft

• Despite the best efforts of the US CAP, the Japanese break through

o The Kates attack CV5 and miss, yet a hammer and anvil attack against CV2 succeeds

 CV2 turned like a whale and could not evade the torpedoes.  

• She takes two on her port side, one ruptures her avgas tanks, which eventually seal her fate

o The Vals attack Lex and hit her twice

o The Vals attack Yorktown and hit her severely damaging her as well

• Lexington goes down

o Avgas fumes spread throughout the ship, it is thought that a spark from a DC powered motor ignited the fumes which eviscerated the internals of the ship, starting uncontrollable fires.

 The first major explosion kills Lex’s main DC party

 IF WE HAVE THE TIME, LET’S GO THROUGH LEX’S DEATH

• Outcome

o Coral sea is technically a draw

 Seen as US strategic victory in that it is the first time the Japanese are stopped

• Port Moresby is not invaded, and the Japanese expansion, at least for now, is checked

 Tactical defeat for the US Navy

• Losing Lex in exchange for Shoho is not acceptable in any way

o Poor FDO operations stationing CAP too low and out of place contributed to losing Lex

o Poor design (prewar design) heavily contributed to Lex’s loss

o Poor US coordination on the morning attack against Shokaku and Zuikaku allowed both to escape the battle

 Sho and Zui would be unavailable for the Midway operation

• Sho due to damage and Zui due to heavy aircrew losses

o What lessons do we learn regarding future operations?