# Pearl Harbor and the carriers?



## Lucky13 (Feb 23, 2015)

What would the USN had done, had the USS Lexington CV-2 and USS Enterprise CV-6 been sunk/damaged at Pearl Harbor, leaving them with USS Saratoga CV-3, USS Ranger CV-4, USS Yorktown CV-5, USS Wasp CV-7 and USS Hornet CV-8?
Mind you, the other carriers would still meet the same destiny, when they did...(if the still went through with the Battle of Coral Sea and Midway)
Would they still have done Coral Sea and Midway battles?
Would they have played it safe, wait for more carriers to be built?
Would the RN have entered the Pacific war sooner?


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## davebender (Feb 23, 2015)

With two CVs sunk USN can no longer afford to employ CV battle groups for propaganda stunts. So there will be no raids on Wake Island and no Tokyo raid. Nor can USN afford to employ a CV battle group as an aircraft transport for Malta.

With these non essential activities cancelled USN has just as many CVs available for Coral Sea and Midway as they did historically.


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## GrauGeist (Feb 23, 2015)

It's entirely possible that the battles that did occur historically may not have happened in the event of losses at Pearl, because this would have dictated a change in strategy.

It would also depend on how bad the carriers were damaged in the 7 December raid, as several capitol (and lessor) ships were repaired and put back into service in a relatively short time: Tennessee (BB-43) back in service February 42, Maryland (BB-46) back in service February 42, Helena (CL-50) back in service summer 42. A few other BBs were back in service as late as 1944.

If any carriers were repaired and put back into service within the year, then this may have only delayed eventual battles, but I am willing to bet that Japan wasn't going to wait for this to happen...


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## tomo pauk (Feb 23, 2015)

The Wasp was sometimes used to ferry RAF aircraft to Malta. Loss of 2 capable carriers would mean that Wasp goes to Pacific from day one, so RN will do the ferrying. So RN will be ill able to send anything to Pacific.
We'd probably see the Atlantic without USN fleet carriers, even without the Ranger.

Attack on Tokyo was probably a much more worth than a publicity stunt. Japanese didn't see it as stunt.


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## herman1rg (Feb 23, 2015)

Did the IJN have a coherent follow up plan?


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## davebender (Feb 24, 2015)

Every competent military has numerous contingency plans. WWII era Japan was no exception. Some of them are detailed in "Shattered Sword".

http://www.lib.utexas.edu/maps/australia/oceania_pol01.jpg
Historical Japan planned to further isolate Australia by occupying Johnson Island during August 1942. That would undoubtedly be followed by other islands further south.

Of course these operations could and probably should have been accomplished ILO Midway during June 1942. So you cannot count on an opponent doing the logical thing.


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## VBF-13 (Jun 13, 2015)

Lucky13 said:


> What would the USN had done, had the USS Lexington CV-2 and USS Enterprise CV-6 been sunk/damaged at Pearl Harbor, leaving them with USS Saratoga CV-3, USS Ranger CV-4, USS Yorktown CV-5, USS Wasp CV-7 and USS Hornet CV-8?
> Mind you, the other carriers would still meet the same destiny, when they did...(if the still went through with the Battle of Coral Sea and Midway)
> Would they still have done Coral Sea and Midway battles?
> Would they have played it safe, wait for more carriers to be built?
> Would the RN have entered the Pacific war sooner?


None of that would have made any difference. They needed Pearl, the Islands. Put an X through all that. They win. Who was going to stop them?


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## mikewint (Jun 13, 2015)

The Carriers at Pearl! One hear this so often. In reality There were only two carriers in the Pacific at the time, Lexington and Enterprise. Saratoga was between Bremerton and San Diego, Yorktown and Wasp were in the Atlantic, along with the Ranger, and Hornet was off Bermuda working up.

Biggest changes: CVN 65 gets a different name, and Star Trek has the Starship Constellation.

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## VBF-13 (Jun 13, 2015)

mikewint said:


> The Carriers at Pearl! One hear this so often. In reality There were only two carriers in the Pacific at the time, Lexington and Enterprise. Saratoga was between Bremerton and San Diego, Yorktown and Wasp were in the Atlantic, along with the Ranger, and Hornet was off Bermuda working up.
> 
> Biggest changes: CVN 65 gets a different name, and Star Trek has the Starship Constellation.


Lol. But yeah, that was pretty much the size of it.


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## mikewint (Jun 13, 2015)

I was, of course being flippant, so a more studious answer:
Everything went almost perfect for the Japanese the first 6 months, so it is real hard for them to speed up. But likely changes:

1) In the first 6 months of war, life is a little bit easier in the Marshall Islands.

2) I think no raid on Tokyo, because the USA will always keep some carriers in reserve at Pearl, and cancel the operation. It takes two carriers to do the operation, so at a minimum it is delayed. Without this operation, and operation like Midway is not approved.

3) With fewer carriers, do we send ships to the Coral Sea? I guess not, but this could go either way. I think this happens even without the Tokyo raid.

4) When we have the 4 carriers available, and we get a chance with the code breakers we will try to take advantage of the Japanese somewhere. The question becomes when and where will the Japanese present an opportunity. These ships spent a lot of time in port.

5) By mid to late 1943, the USA is doing major offensive operations, and their is a chance the USA only does the Central Pacific plan, if which it does, the war is quicker. Once the USA has the huge navy, the operations in the SW Pacific were unneeded. It was a good tactical move to weaken the Japanese with land base airpower before we had enough carriers to do something like Guam.

6) By 1944, in any case, the USA is advancing in the Central Pacific, unless you have another unexpected carrier victory somewhere by the Japanese, or something strange.

So, in short, it ends the same, but probably has a lot less heroic sea battles just a few really big ones, and it maybe pretty quite between Jan 1942 and May 43. Due to Japanese doctrine, one or two really huge naval battles will happen in 43 or 44.


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## syscom3 (Jun 13, 2015)

The Battle for the Coral Sea will be fought as happened. Midway, maybe that will be different. If the US does not attack Japsn, then maybe Yamamoto's planning rationale is altered?


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## GrauGeist (Jun 14, 2015)

The Tokyo Raid might not have been seen as a success from a tactical point of view, since there was nominal damage inflicted.

However, it did have several results, one of which was far-reaching.

First of all, it forced the realization that Japan was not invincible and resources were diverted to defenses throughout the mainland as a result.

Secondly, Japan lost face. They were of the mindset that no one could (or would) dare do something of that nature and yet, there it was. This perpetuated the Battle of Midway not so much as a retaliation, but because Yamamoto realized that the U.S. carriers still posed a threat and needed to be drawn out for a decisive victory.

So Yamamoto's "operation MI" would enable him to draw the U.S. carriers into a great battle, crush them and save face. Sort of an "all in one" kind of deal.

Unfortunately, things didn't work out the way he intended.


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## gjs238 (Jun 20, 2015)

RE: Tokyo Raid:
http://www.ww2aircraft.net/forum/ww...hort-term-ramifications-40319.html?highlight=

RE: Defeating Japan without South West Pacific campaign:
http://www.ww2aircraft.net/forum/ww...paign-douglas-macarthur-41780.html?highlight=


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## pinehilljoe (Jul 25, 2016)

*Jonathan Parshall looked at the economics. In his article he compared if the US had lost Midway. It would have been a one year set back, when you compare carrier production. *

Grim Economic Realities


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## parsifal (Jul 25, 2016)

Japans whole strategy up to Phil sea was looking for the "decisive battle" and from Pearl on that meant destruction of the enemy's carrier fleet whilst retaining their own offensive capability. Supporting their "decisive battle" concept were the operations of their big fleet submarines, that were supposed to inflict heavy attrition on the USN to even up the odds in these climactic battles.

none of these prewar assumptions really worked as they had been intended. The US recovery capabilities were too strong and the Japanese reserves too meagre and replacement rates too slow to be effective. The fleet subs were found too slow to tackle the US fast carrier forces.

If the USN was forced to use all of its fast carriers including RANGER in the front line, its training and aircrew quality would have suffered in a similar way to the Japanese. The limitations on RANGER are in fact such that she would be of limited use in the pacific anyway. That leaves WASP, SARATOGA, YORKTOWN and HORNET. SARATOGA was effectively removed for some months in January due to a torpedo hit from IJN I-boat, that effectively leaves 3 top shelf Fleet carriers to face off against 6 IJN fleet carriers and 4 Light carriers, increasing to another 2 fleet carrier conversions in June/July. a critical question in this early period is whether the USN, with just 3 fleet carriers can generate enough friction to keep the IJN on the hop. a month of reduced operations around March or April will allow the IJN the ability to shore up their crumbling pilot reserves and might induce them to keep their fleet carriers concentrated rather than breaking them into bits for piecemeal attacks as they did. If the IJN can somehow remain concentrated, and threaten vital US interests in the Pacific, they might be able to pull off an upset that buys them some time, say 12 months.

There are a lot of ifs in this alternative, making it less than a 50% chance of success. Likely outcome is that nothing substantive changes, but just the same the loss of two carriers at the outset makes it hard to see things panning out s well as historically was the case for the USN .

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## Wayne Little (Jul 26, 2016)

If's buts or maybe's the japanese would have simply extended the eventual out come as you guys say...maybe 12 months more or less, US industrial power once in gear....game over.

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## vikingBerserker (Jul 26, 2016)

I agree, it comes down to manufacturing.

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## syscom3 (Jul 27, 2016)

Its not only production, but quality. And that compounded the woes of the Japanese.

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## Graeme (Jul 27, 2016)

syscom3 said:


> Its not only production, but quality. And that compounded the woes of the Japanese.



Part of an article from a 1945 Popular Mechanics magazine I have that discusses the quality attribute with land weapons.
Postwar propaganda? Dunno, but it's a fun read.


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## parsifal (Jul 27, 2016)

The IJA in 1942, even 1943 was comparable qualitatively with the US army, despite the bombast about guadacanal and midway that we are doubtless about to receive. In Us led forces did less well elsewhere against the japanese, particularly at buna and of course at the very beginning. Equipment wise the US army was inferior in December 1941, about the same as the IJA the following December (in the pacific) and pulling well ahead by early 1944. By 1945, the IJA was on the ropes quality wise
some of their stuff was good. their 70 inf gun was superior to any comparable gun in the US inventory until the 75mm pack howitzer, and even then the US gun was too heavy. The Japanese relied heavily on their 75mm mountain guns which could be broken down into man portable loads. Allied infantry were in those early stages always limited to mortars that were not nearly as useful as these light artillery pieces. Later the Japanese used their slow firing 8mm Hotchkiss HMGs to good effect, using them to apply mortar style plunging fire into Allied weapon pits in the Jungle

Japanese tactics at the beginning were pretty poor, their experiences in China making them over confident. they relied on archaic bayonet charges and attached insufficient direct firepower to the squad to give it effective fire suppression capability. Their fire discipline for their heavy artillery was terrible, and their efforts at the beginning for concealment laughable. Later they applied camouflage to a masterful extent and got a lot out of their very limited artillery parks. by then it was all way too late, with the US fire support teams just blowing them away in most exchanges . Just the same their defensive abilities were excellent to the end, making them a formidable opponent to the end


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## Shortround6 (Jul 27, 2016)

In actuality the American equipment was fully the equal of the Japanese equipment even at the start of the war, which really leaves the Allied troops lacking in training and leadership. 
The US 75mm pack howitzer was fairly close to the Japanese 75mm Mountain gun Meiji 38 in weight,elevation, traverse, shell weight and range. The American 75mm field guns came in two kinds, the older pole trail versions even if modified for motor towing was pretty much equal to the Japanese Japanese 7.5cm Fieldgun Meiji 38 and when mounted on a split trail carriage was equal to the Japanese 7.5cm M 90. 
The 70mm infantry gun was in a class by itself firing a much lighter shell, (3.8kg) instead of the 6.5-7.0 kg shells of the bigger guns. it also had a much short range. which was compensated by it's much lighter weight and greater portability. It was more of a breech loading rifled mortar. More accurate than a smooth bore mortar and with ability to be fired horizontal. At a scale of issue of two 70mm guns per battalion they were a useful addition but hardly provided overwhelming firepower except in extraordinary conditions. 
For actual combat use rather than target range there was little to choose between the Bolt action rifles of the Americans and Japanese. 
The BAR was not a very good light machinegun but the Japanese were in fierce competition with the Italians as to who could build the worlds _worst_ LMG. Nobody had much for submachine guns at this point and the Japanese heavy machine guns were serviceable but not really the equal of the Brownings. Firing at high elevations to try to get plunging fire down into weapons pits is a nice trick but is also pretty much an admission that your artillery can't do it's job. Not enough barrels/tubes, not enough ammo (chronic problem for the Japanese) poor forward observer system, something is wrong. Artillery had been using airburst for direct observation fire since well before the American civil war. It was the principal behind Shrapnel shells and was extended to howitzers and plunging fire before WW I, at least in text books. Firing hundreds of rounds of MG ammo into the air trying to get a few projectiles into enemy weapons pits is a fringe tactic. 
Mortars were the normal battalion support weapon and some countries were better than others (and supply could greatly affect how the receiving troops viewed their opponents mortars) The US 81mm mortar was supposed to use a light and heavy bomb with different ranges but the heavy bombs saw very little use and the US 81mm light bomb could range to 3000 meters although accuracy could be pretty poor. The Japanese 50mm mortars were little more than Grenade throwers (indeed one projectile was the standard hand grenade with a gas check and propelling charge attached) but whatever advantage the American 60mm mortar had in range may have been lost to field of vision and lack of communications in the company (no feildphones/radios for a company mortar forward observer).
Poor showing of American troops in the early part of the war cannot be placed on superior Japanese weapons.


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## parsifal (Jul 28, 2016)

There was nothing wrong with the M1, except in one critical area. Its all up weight was 1439lbs and this could be broken into a maximum of 6 loads, with the expectation that the gun be carried by mules in rough terrain. fairly reasonable, except that in many parts of the far east there is terrain where mules cant go, and more importantly when weakened, cant really manage the average 239lbs of weight the M1 break down required.

As a consequence the m1 was far less useful in the jungle than it could have been.


By comparison the old type 31 weighed just 738lbs, and could be broken down into 13 pieces, so that the 13man support crew could carry the weapon themselves. They could do so easily, so the gun was very popular with the IJA despite its age.

The type 38 is a field gun weighing in at over 2000lbs, thoroughly conventional and unremarkable. Not extensively used in the Jungle, could not be broken into portable loads. Ive not heard any references to the type 90 being used in the Jungle and I dont believe it was man portable.

The other lightweight jungle/mountain guns on which the IJA relied were the 75mm Type 41 and the better Type 94. The type 41 had some issues, but it was still superior to the M1 whilst there is really no comparison between the type 94 and the m1. the type 94 all up weight was 1141 lbs, and could be broken down into 11 modules, easily man portable. It was a very accurate gun, light, but its lack of a true howitzer trajectory was a problem in mountain jungle terrain.

I think I agree that the successes and failures of both armies in the pacific was primarily an equipment thing. it was a numbers thing a firepower thing and a logistics thing as well as tactics of both armies. but the equipment was reflective of some of their endemic failures and for the US, they failed badly to appreciate the difficulties of fighting in hard terrain. They got around this by modifiying their strategy, using the island hopping strategy. this solved their inability to fight effectively in the jungle, but doesn't get past the fact that jungle fighting was not a US army strong point.

Agree completely about IJA MGs, though the Japanese did get a lot out of what they had, and their Type 99 was far better than their type 96. having to oil cartridges before being chambered is a recipe for disaster in the jungle, and the Japanese mechanisms suffered a lot from jams and other stoppages. The biggest single failure they had was their logistics and in this the US was miles ahead


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## Shortround6 (Jul 28, 2016)

While Jungle warfare was seldom conducted by an entire division operating together on on battlefield (all divisional artillery assets being able to fire on one objective, one ridge or village/town as opposed to a bridge or bunker) the assets of division were varied.
One table of a Japanese standard division shows 18 of the 70mm guns per division, 12 of the 75mm mountain guns (regimental) per division and 36 75mm feild guns or mountain guns. 
I don't believe the the US 75mm pack howitzer was a battalion level weapon except under exceptional circumstances. 
Fighting in the Philippines may be considered Jungle warfare but the US certainly used tanks and even halftracks with 75mm guns let alone towed artillery so the necessity for weapons of like the Japanese 70mm inf gun was hardly universal. 
Most sources say the US M1 pack howitzer was a bit lighter than your number. 1269lbs in action with wooden wheels being one figure. The M8 with pneumatic tires going to 1339lbs. all up weights may vary and weight of pack gun can vary quite a bit when broken down depending on the pack equipment, mule packs/frames and/or man packs/handles and such. 
The Japanese 75mm 75mm Meiji 31 may have been light but that is about all it had going for it, dating from before the Russo-Japanese war of 1904-5.





0 degrees traverse, 30 degrees of elevation and a recoil system that was, to be charitable, marginal. The devices fitted to the wheels in the picture are to help prevent movement on firing. The gun needs to relayed for every shot and the practical rate of fire is 2-3 rounds per minute. 
with a bit over 600 made how many were still in service in WW II is certainly open to question. Like how many survived the 1904 war 
(and how 44 wound up in Finland in 1919) let alone the various military adventures during the 20s and 30s. 
I would also note that the barrel does not come apart and the breech block fits into the rear of the barrel so _*if *_this thing comes apart in 12-13 pieces one of those pieces is going to rather large and heavy. Coming apart in 5-6 pieces is much more believable with 2-3 men carrying the heavier loads.
There are good reasons why the Japanese replaced this thing before WW I. 
Using it as an example of a deficiency in Allied weapons for Jungle fighting doesn't make sense to me. 
The US did have a suitable weapon in inventory although in small numbers in 1941/42 due to doctrine. The 4.2in rifled mortar was in service in small numbers in 1941 although confined to a smoke/chemical weapon due to doctrine issues. The HE shell was showing up about this time. There were 4 companies of these mortars in service as of Pearl Harbor and one was lost at Bataan. It took a while for the conventional troops (read some generals) to accept the Chemical warfare service might have the answer to some of their problems with just a change in ammunition. The US having it's own share of "empire building" going on. It took a while to sort out but eventually (mid 1943 on) the 4.2in mortar came to give good service in difficult areas that conventional artillery could not get to.


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## parsifal (Jul 28, 2016)

We can be a bit more specific as to the forces involved in PNG at least and their make up.

The main offensive land force available to 17A from April '42 through to December was built around a special service group now known as the South Seas Force (or Detachment), which was a composite of a naval special naval landing force (SNLF) and a composite army unit built around the IJA 144 Inf Regt. There were significant numbers of Korean and non-combatant labour units attached to the force, as initially it landed at Gona (and later at Milne Bay) with the intention merely of building advance airstrips. With the failure of Mo the 17A was tasked with the near impossible task of attempting an overland capture of the strategic port of Moresby. no other army in the world at that time would have even attempted such an undertaking. Whatever you say about the poor showing of the IJA, these guys had the gonads to take on what any other army would consider to be an impossible task. They through into the battle basically a brigade sized force, half of which (the SNLF component) were highly mobile, but very lightly armed elite troops.

A look at the TOE of the heavy component of the force (built around 144 Regt) reveals or gives a good indication of the artillery types they were throwing into this battle. the following is from a TOE report just after the capture Guam, ie just before redeployment:

The sSF was brigade sized force formed under the direction of the IJAs jungle warfare expert (col Tsuji) intended to be used in the Japanese seizure of the Sth Pacific. Everything about it was specialised, from the footwear issued to the troops (split towed, lightweight canvas as opposed to the heavy and slippery hob nails used in the Allied clodhopping armies sent to oppose them), to the make up of the force itself. Initially it was tasked with the the capture of islands in the sth Pacific, as well as Wake, Guam, and the Gilberts. We often hear about how badly the US and allied forces were outnumbered in these battles, without acknowledging that in truth, the Japanese in this TO were outnumbered about 4 or 5:1. The forces used to capture rabaul for example were outnumbered by the allied ground forces by about 3:1. This was never battle fought on equal terms in sheer numbers.

The army component of the SSF was drawn from the 55th div and was commanded by Major General Tomitaro Horii. It consisted of the following units:


144 Inf Regt with 2700 men
1st Battalion of the 55th Mountain Artillery Regiment with 750 men and 12 75mm mountain guns (type unknown)
3rd Squadron 55th Cavalry Regiment
1st Company 47th Anti-aircraft Artillery Battalion
Reinforced Infantry Gun Support gp (which I think had 12 70mm IGs).
Infantry gun support gp for the SNLF detachement (maybe 12 guns)
plus Engineer, Communications, Transport and 3 Medical detachments.
The detachment was to be used to seize Guam but was diverted to Wake after the initial unsuccessful attempt by the navy to seize the atoll, where it suffered some casualties (I believe these were made good before deployment to PNG). It later rejoined the 55th Division in 1943 for the NG campaign.

On May 4, 1942, troopships bearing the South Seas Detachment set sail southward from Rabaul for Moresby . Three days later, however, a naval engagement appeared to be brewing in the Coral Sea; whereupon the transports immediately veered back to the north, in order to avoid combat. The Japanese failed to secure victory at coral sea and this caused no small loss to the Fourth Fleet. Plans to land the South Seas Detachment directly at Port Moresby from the sea had to be abandoned.

Imperial General Headquarters, on May 18, 1942, issued an order of battle for the Seventeenth Army, to be commanded by Lieutenant General Haruyoshi Hyakutake. An Army in name only, it was made up of several infantry regimental groups:


35th Infantry
Brigade less 114th Regiment
South Seas Detachment
Aoba Detachment (built around 4th Infantry Regiment)
41st Infantry Regiment, etc.
The mission of the Seventeenth Army in Operation FS was the capture of strategic points on New hebrides islands, new Caledonia, Fiji Samoa, Tuvalu, Tokelau, Tonga, (some sources also say they identified the phoenix islands as an objective). Before any of this 17a was tasked with the capture of Moresbey, at that time defended by a brigade group of the Australian Army.

The objective of these operations was to take possession of strategic island points in order to intensify a cutoff in the contact between the US and australia, while squelching the Americans' and Australians' plans of counterattack from the same areas. Action was slated to begin about the beginning of July 1942.

The objectives were totally unrealistic and a reflection of the dreamworld IGHQ was living in. but the campaign in PNG was to show in spades the disparity in quality between the IJA and their allied opponents at that time. With not much more than a reinforced brigade of troops....about 7500 men, they took on firstly 1 Australian div, then a second Australian Dive then an American Div and finally a reinforced US RCT. in the end, the Japanese forces were utterly defeated, but not before they came within an ace of doing the impossible. the differences I believe can be traced to two critical areas, their ability to get meaningful artillery support into the Jungle, and the amazing mobility their light troops enjoyed with their special kit and doctrines. the Japanese used in their famous flanking moves carried no rice, ammunition only, were very lightly dressed and specially equipped with jungle footwear. time and again they were able to outflank and make obsolete position after position. Time and again the US and Australian positions were pounded by these so called obsolete, useless pieces of artillery which the allies with their "mortars" could not answer. most Australian vets that fought in that campaign that ive met express the envy thay had that the Japanese had Ig support and they had nearly useless mortars only. Moreover, well into 1943, the allies still could not bring to bear heavy weapons into the jungle. Similar things were happening in Burma. My best estimate is that the allies needed odds of 10:1 + in the jungle plus complete air superiority to defeat a properly supplied Japanese force, and this disparity remained the case well into 1943. trouble was, by the end of 1942, a 'properly supplied" Japanese force was all but a memory....

The allies overcame this in a number of ways. in the PNG jungle the Us basically retreated except for a few units. it was too costly and too unproductive for their liking. The Australians, after gona set up their jungle warfare school at Canungra in qld and used surviving veterans to train follow up units. gradually the Australians learnt the difficult art of jungle warfare, that stood them in good sted right through to today.

The Americans learnt a different path, take only what you need, use seapower and air power in place of artillery and blast all opposition out of existence before walking in and taking what you want. Inelegant, but effective I guess.

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## Shortround6 (Jul 29, 2016)

I do appreciate the time and effort you put into your post/s. They do bring a lot to the discussion and add to the Historical perspective. 
However I do believe you have a real bug about these infantry guns. Normal scale of issue for a "normal division" was 2 guns per battalion for the 70mm infantry gun.




or 6 guns per regiment but unlikely for one battalions guns to fire in support of another battalion unless adjacent. 
Standard scale of issue also called for four 75mm mountain guns or pack guns per regiment. The most modern being the model 94 (1934)




But this may have been used in true mountain divisions or regiments and may or may not have been available for the elite Island attack force you describe. Gun was roughly equal in performance and size/weight to the American 75mm pack howitzer but did have much greater traverse.
The nearly standard Japanese regimental gun was the older Model 41 (1908) mountain gun. 




It had a working recoil system and could traverse 6 degrees (same as the American 75mm Pack how), it could elevate to 40 degrees with the breech recoiling down between the two side tubes of the trail. It also weighed about 1200lbs. You don't get something for nothing. 
Now a big question would be were these the guns referred to as the inf guns in the infantry gun support group/s you list above? 
A division had 36 regular 75mm field guns OR Mountain guns in it's artillery regiment and Brigade _might _have had a 12 gun battalion/support group attached to it (detached from parent Artillery Regiment). 
I don't doubt that the older Model 31 mountain gun showed up at times in the Pacific but it does rather require a stretch in credibility that such an elite unit as you describe would be equipped with such a relic or scraping of the far, dark corners of the Emperor's arsenals simply because of it's light weight given it's other limitations. 
BTW photo of the Model 41 on the march. 




carried by men does not mean one man per load. 
All of the Japanese 75mm guns had at least one load that went over 200lbs including the relic. 

I have no real information on why the Australian troops were so ill served by their mortars although all Commonwealth troops believed their enemy of the moment (German, Italian or Japanese) had better mortars than they did. At least in the first few years of the war. I don't know what the Australian scale of issue was but the British only issued two 3 in mortars per battalion in 1940, they later went to six. Early war 3in mortars had a max range of 1600 yds which was increased to 2800 yds sometime in 1942. When the Australians got the improved version I don't know. The 3in was further improved in 1943. Not in range but in durability and better sights. 
The British also tended to view the mortar as the cheapest form of weapon they could get away with. If they could have used explosive filled jam tins as ammo they would have done it. 
It was an Australian Officer who invented the gas seal and rifling engagement later used on the American 4.2 in mortar. He did it right after WW I and was turned down because it would have taken away from the cheapness of the mortar and it's ammunition ( the quantum leap in accuracy and thus reduction in needed ammunition expenditure was ignored).
Poor quality ammo (low manufacturing standards) means poor accuracy. If the sheet metal tail fins are not made accurately or are dented/bent before loading then the mortars accuracy can be severely impacted. 
I have no information if any or all of these situations affected the use of the 3in mortar by the Australian troops in the Pacific. Some of them certainly affected their use By Australian troops in North Africa were captured Italian 81 mortars were prized for their far superior range to the early 3in mortar.

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## parsifal (Jul 29, 2016)

later in the war, Australians were using US issue mortars as well as some home produced stuff. Im not sure what we were home producing but can find out.

tsuji formed the SSF at the IJAs jungle warfare school in Taiwan in 1941, along with a couple of other bits and pieces. he was given a virtual free rein as to what equipment he could have so he pulled in assets from allover the empire. Its a bit of an anathema to talk about standard issue for the IJA. they had theoretical TOEs that they seldom followed in practice. this worked well in the short term but basically wrecked a sound army organisation as they formed adhoc special units for special purposes more or less on immediate whims. it destroyed the esprit de corps that was so essential to an army like the IJA. And robbed their larger units of the ability to fight important fights in a coherent way later as the odds against the Japanese began to pile up.

It could be argued that the SSF was not representative of the greater portion of the IJA, but then if we look at the other great TO that the IJA was engaged in at the time.....Burma...it looks that they wiped floor with the allies there as well.

I do have a lot of respect for the way the IJA used its artillery resources in the Jungle and a healthy respect for the little 70mm and 75mm guns they used to such effect. That's based on the contemporary accounts of the battle in the mountains given by both sides. As far as im aware these little guns delivered fire support out of all proportion to their theoretical potential. Look at some of the campaigns in detail where there was at least some manoeuvre room and try and look past the inherent supply issues that dogged the IJA after 1942, and you will find an army quite competent in its resistance capabilities. sure, the allies were able to chalk up impressive exchange ratios in casualties, for example 20000 lost on saipan to about 2000 US dead. but this fails to take into account the supply issues, the firepower multipliers and the mere fact that the Japanese refused to surrender no matter how hopeless it was. Look at the first half of that campaign and the loss ratios are better.

At places like new Georgia, Lae, Finschafen, even Leyte and the other philipinnes campaigns the Japanese continued to rely on their light artillery as the mainstay of their resistive power. These guns delivered results to the Japanese out of all proportion to their numerical strength, or their fpf capabilities.


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## parsifal (Jul 29, 2016)

I have read somewhere that the M-31 was present in the jungle, but cant remember where the hell I saw it. I will try and locate the source over the weekend


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## parsifal (Jul 29, 2016)

Summary of Australian military outputs

Weapons manufacture included the following:




Short Magazine Lee Enfield rifle - 411,050
Vickers Machine Gun – 11,436
Bren LMG – 17,434
2 pounder anti-tank gun – 1,580
6 pounder anti-tank gun – 900
17 pounder anti-tank gun – 128
25 pounder field gun – 1,905
25 pounder field gun (short) – 219
Bofors 40mm AA gun – 290
3.7 inch AA gun – 497
Owen SMG – 45,463
Austen SMG – 19,905
2-inch mortar – 2,000
3-inch mortar – 3,006
4.2-inch mortar – 300
Machine gun carrier – 4,983
Sentinel tank – 65
Rover light armoured car – 238
Dingo scout car – 245
Beaufort bomber – 700
Beaufighter bomber – 329
Wirraway trainer/bomber – 717
Wackett trainer – 200
Boomerang fighter – 250
Mustang fighter – 18
Tiger moth trainer – 1,070
Dragon transport – 87
Mosquito bomber – 115


Australian shipyards built 113 vessels for the Royal Australian Navy (RAN) and undertook repairs on 4,000 RAN vessels, 500 US Navy ships and 391 Royal Navy ships.

The mortars are all of british origin

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