A Japanese invasion of Hawaii

[Curtis Lemay]

Some of the the Luzon invasion fleets were "huge" but that does not mean cancelling them automatically frees up correspondingly huge quantities of oil. The invasions themselves required only a comparatively short duration at sea due to the close proximity of Japanese controlled ports. Most of the ships used would have had to have been based nearby anyway as they were also being used in the Malaya, Borneo, Mindanao and DEI invasions.

Once you detail your own HI plans it may be possible to do a proper comparison regarding oil usage.

The PI fleet consisted of:

1 CVL
5 CA
5 CL
29 DD
2 Seaplane tenders
Minesweepers and PTs.

They will be in action for most of the campaign - along with huge air support.

The ground forces will require continuous huge ammo deliveries.

The fuel requirements will dwarf the tiny invasion of Maui.

warspite1

So you add a dozen more DD to the KB, you add an invasion fleet + tankers for Midway and then factor in the distances. You then allow for Midway not being taken without problem (like Wake). The Japanese around the PI will likely be harder at work as the suppression of the PI has not been as effective.

By the way, as you’ve taken more than 10% of the IJN out of the OOB and added more operations and replenishment convoys - where have all these destroyers come from?

Again, the Luzon operation is postponed. They have a 19 month stockpile. I still don't think the Maui or Midway operation will in any way compare to the postponed Luzon operation, but even if it does cost a little more oil, they have it to spare.

The destroyers come from the postponed Luzon operation.

[Curtis Lemay]

Regardless of your opinion, what I've described in my previous posts was based on Japanese accounts from the "Pearl Harbor Papers" and "The Pacific War Papers". Peattie's "Kaigun" even has an organization chart in chapter 13 confirming that division of authority in 1941. Pretty sure some of the USSBS reports covering the IJN touch on this aspect as well. The takeaway was that Japanese bureaucracies sucked.

Let me get this straight: You're saying that, in a time of war, a Japanese warship would be denied access to a Japanese controlled port that otherwise had space for it. I want to see real evidence for that.

But for simplicity's sake, this is from the Wikipedia entry on Combined Fleet......
"From 1933, with the Mukden Incident and the increasing tension with China, a permanent HQ staff for the Combined Fleet was established. By the late 1930s, it included most of Japan's warships—only the base units, the Special Naval Landing Forces, and the China Area Fleet lay outside the Combined Fleet."

Sounds like the destroyers were under Yamamoto's control.

So there's a bureaucracy. Yamamoto is deferred to by the political leaders on naval matters. He's their expert. If he wants APDs he'll get them. And, generally, the Navy guys stuck together in the face of the battles with the army. All of this is internal to the Navy.

[Curtis Lemay]

Many pages ago you stated shorter ranged JAAF units would have to cover for the missing JNAF bomber units to keep Luzon suppressed and that to do this the Japanese would need to capture PI territory within range of Luzon. That would obviously still qualify as an invasion. Have you decided on which particular bit of PI territory would be the target of this invasion?

Plenty of Zeros and Bettys (among a lot of other things) left for the PI stuff.

But now with less than the historical JNAF force used against the PI and also now without the JAAF being able to take over from the JNAF there after December?

Why would they not be able to take over if they've captured the southern Phillipine Islands?

[Curtis Lemay]

Peacetime oil consumption. So the 90%+ of the fleet at sea before the shooting started uses the same amount of oil as the same 90%+ sitting in port.

The Midway operation consumed over 600,000 tons of oil. And all they got out of it was a couple of islands they couldn't hold, or even do anything with.

Oil logistics: in the Pacific War,Air Force Journal of Logistics,Spring 2004:

http://www.findarticles.com/p/articles/ ... i_n6172425

"By September 1941, Japanese reserves had dropped to 50 million barrels, and their navy alone was burning 2,900 barrels of oil every hour. The Japanese had reached a crossroads. If they did nothing, they would be out of oil and options in less than 2 years, If they chose war, there was a good chance they could lose a protracted conflict. Given the possibility of success with the second option, versus none with the first option, the Japanese chose war."

The Japanese stockpile was 50,000,000 barrels!

warspite1

Thank-you for emphasising just how precarious the Japanese position was. A number of us have been making this point to you for sometime now, and it looks like you've finally understood. Just 50m barrels in September 1941 with no access to oil income. As said, and as you seem to have finally realised, NOTHING could get in the way of the earliest conquest of the NEI.

You must be really bad at math.

600,000 tons would only be 8% of 50,000,000 barrels.

[Curtis Lemay]

I'll refer to this site:

https://en.wikipedia.org/wiki/Philippin ... 80%931942)

It says the Japanese had 541 aircraft targetted at the PI. Including 156 Bettys and Nells. And 107 Zeros. I'm taking about 32 Zeros and 48 Bettys. That leaves 461 behind, including 75 Zeros and 108 Bettys and Nells. So...85% of the historical strength. Maybe it takes a little longer to neutralize Luzon's air. But not much longer.

The attached map shows that the southern islands were invaded from Palau, not Luzon. That makes Luzon irrelevant to the further operations.

warspite1

And the amendments to the NEI invasion?

As suggested in my earlier post, there looks to be a slight problem with Lemay's PI calculations. The only Japanese aircraft types that could reach the main US Luzon airfields from Formosa were the 263 Zeros, Bettys and Nells. Since he is not going to invade PI territory other than Mindanao, that means other shorter-ranged aircraft types like the JAAF aircraft can not play their historical part in the neutralization of US airpower on Luzon. So by taking 80 Bettys/Zeros away, Lemay has effectively reduced the aircraft numbers that the Japanese could use against Luzon by 80/263 or about 30%. And that is only for December as after that the JNAF aircraft historically had to leave the skies over Luzon and redeploy south to participate in the DEI invasions.

They could be used via the southern islands.

[Curtis Lemay]

Just as an FYI, most of the forces you list here had gone on to bigger and better things within a week of the Lingayen/Lamon invasions. By the start of January, the IJN forces dedicated to the Luzon operations had dwindled to a CL, a ML, a couple of torpedo boats and about half a dozen auxiliaries. And they spent most of their time operating out of Lingayen and just patrolling the local waters.

As for the "huge air support", it was also gone by early January, leaving behind a small force of less than 70 aircraft to support Homma's efforts against Bataan.

Interesting how 70 aircraft on Luzon are "a small force", but 80 aircraft on Maui are not.

The ground forces will require continuous huge ammo deliveries.

They didn't. Homma's forces primarily operated off what they had landed with at Lingayen and Lamon. They could do this because they did not fight the first of their major land battles until January. The last of Homma's army forces had arrived at the beginning of January. After that there were no supply or reinforcement convoys sent to Luzon until more than a month later.

And the battle went on for months.

The fuel requirements will dwarf the tiny invasion of Maui.

Prove it. All you have to do is supply a detailed layout of your full plan and we can begin a proper comparison.

Again, even if it somehow consumes more fuel than Luzon - a huge if - they have a huge oil stockpile

[Curtis Lemay]

Soooooo much is dependent upon this. Somehow the Japanese have to co-ordinate their bombing of Pearl by the Bettys so as not to alert the defenders before the carrier strike - but not be too late and face an alert enemy.

They have these things called radios. They will detect the "Tora! Tora! Tora!" signal. Then they will know they can attack.

The destroyers have to evade detection from the flying off point to Maui. And then co-ordinate their landings - again so as not to alert the defenders at Pearl and yet have sufficient time to subdue the defenders on Maui and secure the airfield and ports to allow unloading of the supplies and equipment, ammunition, AA guns, fuel (and ground crew) for the Bettys.

The destroyers do their entire run at night. There are Japanese spys on Maui providing pathfinding service. Supplies, along with the air crews don't start till after the strike begins - getting there about 1-2pm. The port will be in Japanese hands by then, so they can just use the port.

I mean there is absolutely no possibility of cock up is there? Within hours of the Pearl Harbor strike the Japanese could suddenly find themselves in huge trouble. Scratch two flotillas of destroyers, two battalions of troops, ground crew, spares, ammunition, fuel etc + all the Bettys....

Low risk - high reward. A TWO YEAR delay in US response.

The delay in taking the PI, and the disastrous effect that could have on the NEI would have all been for nothing and at huge cost.

What disastrous effect? This would have nothing to do with the NEI. That's thousands of miles away!

But hey, they may have taken Midway as compensation - although even that operation is all a bit pie in the sky at present as there is still no word on timing and naval forces to be employed.

So many ground forces have been freed up via postponing Luzon that the invasion force will be overwhelming.

[Curtis Lemay]

They will then at some point be reinforced by Zeros. But like with the iniital invasion of Maui, we are somewhat light on details of timings and units that will be available for all this.

The Zeros will come from a group from one of the carriers. Instead of coming back from the last strike on Pearl, they will just land on Maui instead. Then that group will be replaced by the group from the Luzon operation later.

[RangerJoe]

The oil stockpile was stated from September. Some oil was used in the meantime and not replaced. How much is left?

[warspite1]

They will then at some point be reinforced by Zeros. But like with the iniital invasion of Maui, we are somewhat light on details of timings and units that will be available for all this.

The Zeros will come from a group from one of the carriers. Instead of coming back from the last strike on Pearl, they will just land on Maui instead. Then that group will be replaced by the group from the Luzon operation later.

warspite1

Sadly its the same old nonsense. You continue to use the KB in different ways according to what you are answering.

Listen, when you've decided what the KB are going to be doing and when, let us know. Until then, nothing you say about their usage is worth listening to.

You realise that the conquest of Wake need two carriers, two heavy cruisers and a couple of destroyers from the KB because the Japanese under-estimated what was required? So who is to say they won't make the same mistake with Midway - not that you've even bothered with putting together a likely task force for that operation.

[warspite1]

So many ground forces have been freed up via postponing Luzon that the invasion force will be overwhelming.

warspite1

I know you think all Japanese are supermen with the power of Bushido - but even you know they can't walk on water right? How do these troops get there?

[warspite1]

.

[Orm]

Low risk - high reward. A TWO YEAR delay in US response.

So how is the reasoning for this two year delay? Couldn't US fight back somehow because of the loss of a few islands? So far the plan calls for isolation of HI, and not capture, if I get the current plan correctly. Seems to me that the occupying Japanese forces would be isolated as well as soon as the combined fleet turned its attention elsewhere. Keeping those Japanese in supply would have been hard then.

[warspite1]

What disastrous effect? This would have nothing to do with the NEI. That's thousands of miles away!

warspite1

...and so it continues... World War II in silos....

[warspite1]

Soooooo much is dependent upon this. Somehow the Japanese have to co-ordinate their bombing of Pearl by the Bettys so as not to alert the defenders before the carrier strike - but not be too late and face an alert enemy.

They have these things called radios. They will detect the "Tora! Tora! Tora!" signal. Then they will know they can attack.

The destroyers have to evade detection from the flying off point to Maui. And then co-ordinate their landings - again so as not to alert the defenders at Pearl and yet have sufficient time to subdue the defenders on Maui and secure the airfield and ports to allow unloading of the supplies and equipment, ammunition, AA guns, fuel (and ground crew) for the Bettys.

The destroyers do their entire run at night. There are Japanese spys on Maui providing pathfinding service. Supplies, along with the air crews don't start till after the strike begins - getting there about 1-2pm. The port will be in Japanese hands by then, so they can just use the port.

warspite1

Radios don't help the Bettys when over PI and the airfield on Maui is still in US hands. Please keep up.

Please give a timetable - hundredth request. When do the destroyers unload their troops for the attack on Maui? How long does it take to attack and secure the key port and airfield and subdue the defenders?

Try providing detail.

[warspite1]

Oil logistics: in the Pacific War,Air Force Journal of Logistics,Spring 2004:

http://www.findarticles.com/p/articles/ ... i_n6172425

"By September 1941, Japanese reserves had dropped to 50 million barrels, and their navy alone was burning 2,900 barrels of oil every hour. The Japanese had reached a crossroads. If they did nothing, they would be out of oil and options in less than 2 years, If they chose war, there was a good chance they could lose a protracted conflict. Given the possibility of success with the second option, versus none with the first option, the Japanese chose war."

The Japanese stockpile was 50,000,000 barrels!

warspite1

Thank-you for emphasising just how precarious the Japanese position was. A number of us have been making this point to you for sometime now, and it looks like you've finally understood. Just 50m barrels in September 1941 with no access to oil income. As said, and as you seem to have finally realised, NOTHING could get in the way of the earliest conquest of the NEI.

You must be really bad at math.

600,000 tons would only be 8% of 50,000,000 barrels.

warspite1

No, Maths is okay. What exactly does the above prove? You know the oil is needed for all ships, aircraft, vehicles and Japanese industry right?

[warspite1]

The PI fleet consisted of:

1 CVL
5 CA
5 CL
29 DD
2 Seaplane tenders
Minesweepers and PTs.

They will be in action for most of the campaign - along with huge air support.

The ground forces will require continuous huge ammo deliveries.

The fuel requirements will dwarf the tiny invasion of Maui.

warspite1

So you add a dozen more DD to the KB, you add an invasion fleet + tankers for Midway and then factor in the distances. You then allow for Midway not being taken without problem (like Wake). The Japanese around the PI will likely be harder at work as the suppression of the PI has not been as effective.

By the way, as you’ve taken more than 10% of the IJN out of the OOB and added more operations and replenishment convoys - where have all these destroyers come from?

Again, the Luzon operation is postponed. They have a 19 month stockpile. I still don't think the Maui or Midway operation will in any way compare to the postponed Luzon operation, but even if it does cost a little more oil, they have it to spare.

The destroyers come from the postponed Luzon operation.

warspite1

Yep Luzon is postponed. We know. And that is a major problem for the Japanese. Big, big problems given they only have about 18 months of oil and, once the Pacific War starts, that oil is going to disappear even faster.

You can keep repeating the same boring mantra that everything comes from the Luzon operation, but until you actually put some detail on your plan, no one believes that the Luzon saving is enough and no one believes that the NEI operation is not, at best, delayed.

With all the extra operations you have used so many destroyers elsewhere. The destroyers used in the PI were needed - and used - by Japan elsewhere. But with your unrealistic assumptions and insistence that WWII was fought in silos, you simply double up on the use of destroyers, carriers and key aircraft. Its a really poor effort to be honest.

[Aurelian]

They will then at some point be reinforced by Zeros. But like with the iniital invasion of Maui, we are somewhat light on details of timings and units that will be available for all this.

The Zeros will come from a group from one of the carriers. Instead of coming back from the last strike on Pearl, they will just land on Maui instead. Then that group will be replaced by the group from the Luzon operation later.

warspite1

Sadly its the same old nonsense. You continue to use the KB in different ways according to what you are answering.

Listen, when you've decided what the KB are going to be doing and when, let us know. Until then, nothing you say about their usage is worth listening to.

You realise that the conquest of Wake need two carriers, two heavy cruisers and a couple of destroyers from the KB because the Japanese under-estimated what was required? So who is to say they won't make the same mistake with Midway - not that you've even bothered with putting together a likely task force for that operation.

We know that the Zeros would not come from the carriers. Unlike US practice, the carrier airgroups were permament to the carriers. It's Japanese doctrine. After Coral Sea, Zuikaku and Shokaku were not available for Midway. the former because of damage, the latter because of air group losses. There was no thought what so ever of putting Zuikaku aircraft on Shokaku.

[Aurelian]

http://www.pwencycl.kgbudge.com/O/i/Oil ... d%20States.

The Japanese Navy was well aware of the vulnerability of its fuel supply, and it had been stockpiling oil since shortly after the First World War. So great was the perceived need that, from 1925 through 1930, part of the appropriations for naval construction were secretly diverted to oil purchases, a fact the Navy concealed from its own government. The Navy also succeeded in pressuring the government to enact the Petroleum Industry Law in 1934, which required civilian oil companies to build up a reserve equal to half their annual imports. This was ostensibly to ensure that there would be a sufficient wartime supply of oil for civilian use without dipping into Navy stocks. After 1937, the Navy began a crash program to stockpile high-octane gasoline and isooctane as well.

By 13 March 1941, the Japanese had managed to stockpile about 42.7 million barrels of oil, primarily from California and Tarakan. This was stored in some 7000 oil storage tanks, also purchased from the United States. Navy petroleum product reserves on 1 December 1941 were 1,435,000 tons of crude oil; 3,634,000 tons of of bunker fuel; 473,000 tons of aviation gasoline; 27,000 tons of isooctane; 6400 tons of aircraft lubricants; 13,600 tons of ordinary lubricants; and 921,000 tons of petroleum derivatives already loaded on ships or distributed to overseas bases. This was thought to be sufficient for the first year of war, but consumption greatly exceeded prewar projections. The Army estimated it would require 5.7 million barrels of oil per year while Navy requirements were estimated at 17.6 million barrels per year and civilian requirements at 12.6 million barrels per year. This proved to be a considerable underestimate in the first two years of the war.

https://www.histclo.com/essay/war/ww2/stra/w2j-oil.html

Japan had to import most of its oil in peace time and from the United States. War would require vastly increased oil supplies. Waging naval war in the vast stretches of the Pacific would mean huge increases in oik consumption. Japan had oil stockpiles that could supply its normal needs for 2 years, but only about 1 year if Japan went to war because of the huge increased requirements to fight a naval war. The American oil embargo set in motion a time table. Japan with the clock ticking had either to decide to cease aggression in China or go to war before it ran out of oil. The oil embargo and assets-freezing order according to one historian 'made war with Japan inevitable'. Morison, Samuel Eliot. U. S. Naval Operations in World War Vol. III The Rising Sun in the Pacific.

[Platoonist]

Soooooo much is dependent upon this. Somehow the Japanese have to co-ordinate their bombing of Pearl by the Bettys so as not to alert the defenders before the carrier strike - but not be too late and face an alert enemy.

The timing makes no sense. Somehow these G4M Betty bombers are supposed to appear in the skies over Pearl simultaneously with the carrier attack? Could somebody explain to me how the Japanese seize both Midway and Wake ahead of time as preliminary stepping stones for this shuttle Betty raid without the garrison of either base getting an alarm out on the air to Pearl that they're under amphibious assault and thus blow the whole "surprise" element of a surprise attack? If Pearl gets word pre-dawn on December 7th that either of these mid Pacific installations just west of them are under attack, then Army air forces on Oahu assume Alert Two and the Fleet goes to Material Condition Zed. Even if it is Sunday and even if they aren't under attack yet.