WI: Maximally Effective Pearl Harbor attack?

Sure they would. The idea of carriers>>battleships wasn't really established yet, and having the ships on the move (instead of sitting ducks at port) would seem attractive even to anyone who did feel that way. Just ask the Prince of Wales and Repulse a few days later. Besides, from a more practical perspective, they would have support from land-based air from Hawaii, so it's not like they would have been defenseless.

I think the Pacific Fleet at sea would be a formidable target for Kido Butai. 7 battleships, a dozen cruisers, several dozen destroyers, at battle stations, able to manuever, with mutual support, and under the cover of land-based air. When was a naval force that large attacked from the air? I can't see the USN losing more battleships lost than historically. Also, the fleet wouldn't move out of range of land-based air without having the carriers along. The USN's exercises always featured carriers supporting the battle line.
 

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After a maximally effective PH, which would include sinking the carriers of the Pacific Fleet...what then for the Japanese? How do they really follow up on a victory like that before the US naval construction program take effect?
 
Personally I think had the carriers been near enough that the battleships and other naval asset sortie out of range of land-based air over the deep ocean but still being seperate from said carriers and disorganized and rushed, the Japanese can sink pretty much the entire fleet, or at least the battleships and carriers with loss of all crew, then returning to the base to wreck the sub pens, repairs facilities, tank farms, airports, barracks, etc.

Also attacking on a weekday so much more casualties for the U.S. and make sure the declaration of war is delivered before said attack.

Then with the Americans out of position take down Midway, and fight like hell when the Americans return in 1943.
 
I went and rechecked the book, Zimm states that three commercial tankers were delivering 40000 to 50000 thousand ton of fuel a month. So hire more commercial transports to ship more fuel. I don't know how big those commercial tankers were but I figure it the navy needed the fuel they could find 3 to 6 more commercial tankers of equivelant size in the merchant fleet even if they had to bring them in from the atlantic to rebuild the fuel supply and support the war. The capacity of the Pearl Harbors tanks at the time of the attack was according to Zimm the total capacity of the fuel farms were 563,000 tons. He also states that the 5.4 million barrel underground complex of 20 vaults was not in existence at the time and the first one of the vaults did not come line until ten months after the attack.

There was a shortage of tankers available to ship both military and commercial oil on both the Atlantic and Pacific coasts. The US was shipping oil to the UK and the Brits had requested an additional 50 tankers under Lend-Lease for their own purposes, prompting calls of gas rationing on the East Coast by Harold Ickes, Sr., petroleum coordinator.
I believe that Zimm plays down this shortage when he made his comments about replenishing the oil supply at Pearl.
I tend to place more credence on comments from CINCPAC on whether the fuel tanks were important or not. "Admiral Chester W. Nimitz summed up the situation best, “Had the Japanese destroyed the oil, it would have prolonged the war another two years.”"
 
I tend to place more credence on comments from CINCPAC on whether the fuel tanks were important or not. "Admiral Chester W. Nimitz summed up the situation best, “Had the Japanese destroyed the oil, it would have prolonged the war another two years.”"

The issue is not whether destroying the oil would have had an impact, the issue is did the Japanese relying on the weapon loads of carrier based single engined bombers have the capacity to destroy the oil? Blowing up tank farms is a lot more difficult than is often portrayed in the movies. To sustain itself fires needs three things: heat, fuel and oxygen. Now fuel; we got lots of fuel, heat; well the exploding bombs will provide the initial heat and of course oxygen....ah now there we run into all kinds of problems unless we get all the bombs to go off in exactly the right spot as the oil pushes out all the oxygen.

Without fire you are then reduced to trying to blow up liquids and blowing up liquids is hard.

It is also worth recalling as pointed out above that the air above Pearl is now heavily congested with smoke, making accurate sighting on the target hard, that smoke is rising on plumes of hot air making holding a good bombing line harder, there is a very angry bunch of anti-aircraft gunners pumping shells into the sky something that tends to discourage pilots from flying a stable course and then there are fighters in numbers which is also likely to be a bit off putting largely because in a good few cases it will turn out to be fatal for the KB aircrews.
 
Admiral Chester W. Nimitz summed up the situation best, “Had the Japanese destroyed the oil, it would have prolonged the war another two years."

Chester W. Nimitz is one of my heroes but just because he said it does not make it true. You can find any number of statements like that by senior leaders that do not stand up to the test of rigorous analysis.
 
RodentRevolution is correct about what is really important whether the Japanes planes could have destroyed the fuel farms. He is also right about the level of difficulty to start the fires. Furthermore even if some fires did start the individual tanks had berms designed to be high enough with to keep the fuel in its tank away from the other fuel tanks. With sprinkler systems to keep the level of heat down and fire fighting foam retardant systems built in with every tank. To attack and destroy the fuel farms would be extremely difficult
 
Slightly off the wall, If half a dozen Tankers had been diverted from the Texan ports to Pearl Harbour immiadetley afte the attack then they might not have been lost on the east coast during the slaughter of shipping that was the 'second happy time' for the U-boats. Pearl Gets it's oil and more tanker capacity exists in early to mid 1942. a win-win for the Yanks!
 
Slightly off the wall, If half a dozen Tankers had been diverted from the Texan ports to Pearl Harbour immiadetley afte the attack then they might not have been lost on the east coast during the slaughter of shipping that was the 'second happy time' for the U-boats. Pearl Gets it's oil and more tanker capacity exists in early to mid 1942. a win-win for the Yanks!

Is it worrying that this is is probably the most sensible thing that anyone has said on this thread?
 
One question I have to ask is, does this assume the same situation as OTL on the American side, or are we playing both sides?

As to hitting the tank farm, here's a picture of it:
sbph1941.jpg


It would take at least 25 aircraft to completely destroy the farm. Realistically, there are many easier targets to have a go at, like the dry docks, or the torpedo store
 
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One question I have to ask is, does this assume the same situation as OTL on the American side, or are we playing both sides?

As to hitting the tank farm, here's a picture of it:
sbph1941.jpg


It would take at least 25 aircraft to completely destroy the farm. Realistically, there are many easier targets to have a go at, like the dry docks, or the torpedo store

This gets to the point I made earlier. Your at least 25 aircraft assumes a 100% hit rate per aircraft which does not happen today in the era of PGMs let alone then. Back to my earlier point, Pearl Harbor is a massive set of targets from a stand point of facilities and critical infrastructure. Doing significant damage to the base would require persistent re-strikes over an extended period of time. Something well beyond Japan's capabilities.
 
There is a major difference between The Pembroke dock oil farm and Pearl Harbour. At Pearl each tank is in an individual berm. whereas at Pembroke each berm contains 3 to 4 tanks. Hence three bombs at Pembroke can take out between 3 and 12 tanks imiadetely and cause a fire three to four times the size of an equivalent strike on Pearl's tank farm.
 
Hello all,

Imo it was in no small part due to just luck that CV-2 and CV-6 were not in port, certainly CV-6 was due to be there on the morning on the 7th. So indeed for maximum effect, sinking CV-2 and CV-6 at their berths would be far more important in the short them that those tank farms etc. Now that i think of it, and reading that the fuel tank farm and drydocks etc. were not on the IJN priority target list, looks like this whole hoo-hah about the tanks and drydocks is purely something that gained traction in hindsight, maybe even after the war (just like the fact that if the DoW was delivered in time this would have somehow changed the US public's attitude toward Japan and the war; i have made the case some time back that this would not have been the case, the propaganda would simply slightly changed it's "story" to be sold, but it would be just as visceral). After all, what good would be pristine fuel tanks farms and drydocks if the bulk of the Pacific fleet BBs AND CVs are at the bottom of the ocean on the 7th?

Anyway, as this topic is about what the IJN could have done to maximize the effects of their strike, how about being one day late for whatever reason? It's something that could have easily happened imo. CV-6 would be in port, and as i understand it, some of the BBs were always going out for maneuvers during the week. So on Monday morning, there would be several BBs just exiting port and one juicy CV berthed. Any idea what were the peacetime ship movement plans for that Monday?

Not sure how CV-2 can be taken out as well, likely it would have delivered the planes it carried for Midway and would be on it's way back. Maybe things might be a bit different on Monday and CV-2 is directed right in the path of the retreating Kido Butai. Things could go several ways from there, but for the purpose of this ATL if CV-2 is summarily clobbered by D3A and B5Ns from SIX IJN carriers, then that would be a catastrophe for USN. Even worse if torpedo magnet CV-3 Saratoga swallows 2 or 3 torpedos from one of the IJN subs around after it arrives off PH, either being sunk outright or being under repairs for even longer than in OTL! So then you have just CV-5,7 and 8 in the Pacific to do the initial pinprick raids, Coral Sea, Midway and if the leadership is very adamant about it, the Dollittle raid as well. Something will give being so stretched, if for whatever reason even one of them is not available for Midway, this hugely increases the likelihood of an IJN victory, losing there will butterfly away Guadlacanal at the very least. If they still do the Tokyo attack they lose or do not contest Coral Sea. All in all 1942 an 1943 could be a lot harder and bloodier for the americans in the Pacific, and who knows what repercussions all this would have in the ETO.

In summary, in the best case scenario for them the IJN could outright sink 2 or 3 CVs and 3 or 4 BBs, which could not be raised and repaired if they are sunk in open waters (the BBs), or would likely be too smashed up to worth rebuilding (the CV-6). They might lose at least twice as many aircraft in the process but if this would prevent the disaster at Midway it would have well worth it in the short/medium term.
 
HAD the fuel tanks been destroyed what would situation be for carriers? when they returned to Pearl would they normally have large reserve of fuel?

meaning would they have to stay idle at Pearl until tankers arrived or would they be forced to go to West Coast (or could they press on to Philippines?) does not seem like good choice of any?
 
HAD the fuel tanks been destroyed what would situation be for carriers? when they returned to Pearl would they normally have large reserve of fuel?

meaning would they have to stay idle at Pearl until tankers arrived or would they be forced to go to West Coast (or could they press on to Philippines?) does not seem like good choice of any?

They could refuel from the half dozen fleet tankers that existed in Dec 1941. It is correct that at sea refueling was still in its infancy, but ship to ship transfer in harbors was fairly common and not radically different from dockside refueling. There were harbor barges commonly used for that. Those would take on fuel from any source including regular tankers and could refuel a ship anywhere in the harbor Overall the Allies had a robust tanker fleet. The main problem was rapid changes in priority for fuel deliveries in 1941 and consequently several hundred tankers in the wrong locations. On a emergency basis I have no found a serious obstacle to supplying the Pacific fleet absent the Oahu fuel tanks. Its more awkward & slower & less efficient, but allow operations out of Oahu to continue.

Since a large number of the US carrier operations were based out of Wellington & related points in the SE Pacific - not Oahu, those ops are not affected.The USN made a decision sometime early in 1942 to use Wellington or New Zealand as its hub for S Pacific operations and from then set a priority on keeping the reserves up in that region. So no, a hypothetical destruction of the Oahu fuel tanks does not 'end' USN Pacific operations. Bunker fuel for the depots in the S Pacific came from the refineries in the US or Venezuela, not the Hawaiian islands. Operations based from Oahu can be supplied through ship to ship transfer if the USN wants to.
 
Follow up questions. In the aftermath of a maximally effective attack on Pearl Harbor (which may or may not involve an attack on the fuel stores), what can the Japanese navy do to follow up on the attack?

Furthermore, what effect is this likely to have on how the rest of the war plays out? I assume that Japan's defeat is more or less guaranteed in the long-run, but would more significant naval setbacks for the allies delay the end of the war?
 
Follow up questions. In the aftermath of a maximally effective attack on Pearl Harbor (which may or may not involve an attack on the fuel stores), what can the Japanese navy do to follow up on the attack?

Furthermore, what effect is this likely to have on how the rest of the war plays out? I assume that Japan's defeat is more or less guaranteed in the long-run, but would more significant naval setbacks for the allies delay the end of the war?

As I said on another thread, overall, Yamamoto probably behaves like he did OTL. He'll view the PH attack as having given him the breathing space he needs and he'll proceed as planned. Nimitz will start using his carriers to make attacks around the periphery and sooner or later those attacks will become annoying enough that Yamamoto will have to start using his carriers to counter Nimitz. Depending on what else is going on, he will likely not have all six of his big decks at any one time and at some point and time there will be a meeting engagement between two more or less equal fleets. While a Midway style win (for either side) is a possibility, the end result is probably more along the lines of both sides giving each other a badly bloody nose. One thing a more successful PH attack will not do is translate into any major amphibious assaults anywhere - not Hawaii, not Darwin, not Ceylon, not Madagascar, and not anywhere else. They did not have the shipping and more important the army did not have the spare troops and would have balked at any such suggestion.
 
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