Nanshin! or the ramblings of Local Yokel

Post descriptions of your brilliant successes and unfortunate demises.

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Local Yokel
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RE: Nanshin! or the ramblings of Local Yokel

Post by Local Yokel »

Economic consequences of the campaign to date

Here's a spreadsheet summary of what has been captured so far in the SRA.

The 'Maximum Attainable Gains' columns show what was apparently up for grabs in CHS scenario 157. Red figures in these columns show the few 'potential' captures that still remain.

The 'Actual Gains Attained' columns show exactly that, but I've colour-coded them to show the partial captures (orange) and the disasters (red), where the defenders seriously damaged/totally destroyed what was available.

Actually, the Japanese player loses out in this scenario, because Belitoeng never yields any resource centres. They're in the database, but unfortunately they only appear in the second slot, and since the first slot is vacant it seems the Japanese player never gets the benefit of them.

At the foot of the sheet is a calculation of the percentage of gains actually attained. Arguably, the lower the percentage of manpower captures the better, given how they grab precious resources.

As can be seen, apart from Belitoeng the only major disaster was Soerabaja, where the defenders did a comprehensive job of destroying anything of value to the invaders.



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Local Yokel
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RE: Nanshin! or the ramblings of Local Yokel

Post by Local Yokel »

Next, here's a further spreadsheet with a snapshot of the Japanese economy's current state. I've applied an arbitrary 1% to reflect 'shrinkage' resulting from transport of resources from port of landing to place of use.

Notwithstanding the additional resource centres captured in the SRA, there's still a daily deficit of 277 resource points required by HI and all those greedy mouths. That's where the damage done at Soerabaja and the absence of resources from Belitoeng hits home. As you might expect, I'm taking steps to repair the damage done at Soerabaja.


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RE: Nanshin! or the ramblings of Local Yokel

Post by Local Yokel »

Blueprint for a sea bridge

With the SRA largely taken I can now start implementing plans for moving Japan's gains to where they will do her economy some good, i.e. primarily in the home islands. I admit to having adopted wholesale the approached recommended by Nemo121 in aztez' Red Storm Rising AAR - thanks, Nemo, that was really helpful!

Yet another spreadsheet shows what is required to service the principal Japanese resource and oil production centres in the SRA. Daily production figures I obtained via Bohdi's utility, as well as voyage times based on a 9 knot rate of advance - i.e. a fuel-efficient cruising speed. Loading/unloading is assumed to require 50% of voyage time, as per Nemo's recommendation, but this may prove over-generous, in which case there's room for optimisation of the cycle. One factor that will need to be taken into account is the extent to which the outbound journeys can be used to lift supplies, fuel and troops to the Empire's outer reaches, as this will obviously increase loading/unloading times.

The spreadsheet only shows the principal oil and resource ports from which the Japanese must lift cargoes, and reveals total cycle times ranging from 37.5 to 52.5 days. I have modified these by adopting two basic cycles: one of 39 days and one of 49 days. What I have in mind is an interlocking convoy system, in which subordinate convoys sharing the same cycle time combine at convenient points along the Japan-bound route, and disperse again into separate components on the return route.

What is interesting about the spreadsheet is the extent to which it reveals the tankship bottleneck in CHS. The Japanese player starts with only 34 tankers having a capacity of 10680 or greater (i.e. the whale factory ships) and only a few more of the smaller 6000 capacity. As can be seen, using a combination of 39 and 49 day cycles a total tank capacity of 593400 is required, which can be satisfied (just) by pressing all of Japan's tankers into service. However, that's not going to be good enough, given that the Empire has other minor sources of oil supplies (notably E. Sumatra, Ambon and Burma), and will also need to shift substantial quantities of fuel to destinations far removed from the oil ports of the SRA - e.g. Truk. Furthermore the model makes no allowance for tanker downtime whilst fleet members undergo maintenance to make good accumulated sys damage, or Allied attrition which sooner or later is going to bite. Inevitably it appears that all the Shiretoko's and like oilers will need to be pressed into cargo service, at least until the existing fleet is supplemented by new construction. Indeed there may be a case for accelerating construction of tankers in the pipeline.

The bright spot from Japan's viewpoint is that no more than 55 5000-capacity cargo ships are required to lift the bulk of resource production. This leaves Japan with an enormous surplus of AK's, some of which could, at a pinch, be impressed for carriage of cased fuel whilst tankers are unavailable. Inefficient, but you have to make do with what you've got.


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RE: Nanshin! or the ramblings of Local Yokel

Post by Local Yokel »

As before, some end-of-month reports for March 1942, starting with aircraft production/stockpiles and the economy:

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RE: Nanshin! or the ramblings of Local Yokel

Post by Local Yokel »

The stockpiles graph updated to 31 March 1942. This reveals a jump in oil and resources resulting from the fall of Palembang, but the resources peak gets consumed quite quickly. Pleasingly, there's still an upward trend in supply and fuel generation, but this may be as good as it gets for Japan before Allied attacks begin to bite. In particular, I'm not expecting the oil and resources captured in Burma to remain immune for long, as I expect them to come under effective air attack within the next few months. I look on them as nothing more than a bonus Japan enjoys only for so long as the Allies remain weak.

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Local Yokel
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RE: Nanshin! or the ramblings of Local Yokel

Post by Local Yokel »

Now for the intelligence summary screen as at 31 March 1942, with changes highlighted in yellow, as before. IJA losses have gone up a bit more than I would have liked, but Allied ground forces have suffered a good deal more severely. However, most of those losses are represented by the Dutch defenders of Java; no substantial inroads have been made into quality Allied LCU's.

One good point about operations on land is that I managed to block Rangoon's defenders' line of retreat by staging an armoured motor tour round Magwe. That netted me another two brigades, albeit not of high quality.

It's been a fairly quiet month at sea, whilst in the air the Allied to Japanese loss ratio has declined somewhat. Japanese operational losses are now lower than Allied (just), indicating that it is possible for Japan to keep these in check if careful attention is paid to the weather and fatigue.

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RE: Nanshin! or the ramblings of Local Yokel

Post by Jim D Burns »

ORIGINAL: Local Yokel
and will also need to shift substantial quantities of fuel to destinations far removed from the oil ports of the SRA - e.g. Truk.

I'm pretty sure AK's can move fuel for you. I've been away from the game a year and haven't tried it yet in my new PBEM, but I think AK's can haul fuel but not oil if my memory serves me.

Jim

Edit: oops hadn't read your entire post as yet, D'oh! Ignore me, LOL
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RE: Nanshin! or the ramblings of Local Yokel

Post by Cuttlefish »

Very nice analysis of the oil/fuel situation. The lack of excess capacity in your tanker fleet makes me wonder how much tonnage your opponent needs to sink to put your economy in trouble. Have you looked ahead at the new construction and figured out what level of losses you can sustain?

I haven't played CHS but it looks as though the submarine/ASW battle may be much more critical here than in a stock game, especially if Cantona realizes and tries to exploit this vulnerability.
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Local Yokel
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RE: Nanshin! or the ramblings of Local Yokel

Post by Local Yokel »

Jim - yes, oil transportation by AK's is a no-no, but they can certainly be pressed into service to carry fuel.

Thanks Cuttlefish! Fortunately CHS provides a reasonable number of tankers in the construction pipeline, though some of them are the Japanese standard cargo type fitted out as a tankship, in which the capacity isn't very great. However, I haven't yet totted up details of the capacity added by new construction to determine the point at which losses become critical.

In any case, I wasn't happy with my previous oil transportation plan, so here's another one based on rather different premises.

First, oil will move in dedicated tanker convoys (which is what the Japanese actually did, in the end), and these convoys will move at mission speed rather than cruise, giving them a 13 kt rate of advance.

Second, I've tried to factor in more accurate calculations of the loading times at different ports, taking into account port size and tanker size. This can become critical at small ports like Miri, where it takes 11 days to fill a 10680 capacity TK. (By the time you've filled a whale factory ship there the war is already over [;)])

Third, I've made some more exact calculations of how the feeder cycles from the minor oil ports link into the two main lines. The best arrangement I've yet come up with is one group of ships in each feeder cycle's 'set' tarvelling with the main line convoy into which it feeds, whilst the other group is making the voyage to and from the minor port. The two groups alternate these roles. This means that ships in the feeder services discharge their cargoes in Japan, rather than the port at which they join the main line convoy; this saves unnecessary loading/unloading. I suspect there's still room for improvement in this arrangement.

There are a couple of advantages in this arrangement. First it's making better use of the limited number of 10680 capacity tankers: at any time 4 of the initial TK's available can be down for maintenance (which is going to be needed, as sys damage will accumulate more quickly due to the ships being pushed at higher speeds). Second, the arrangement actually leaves a surplus of small TK's for potential use on the South Seas fuel shuttle, or as reserve capacity.

A couple of other points:

The whale factory ships are impressive, but the extra time they take to load complicates the planning. A possible solution would be to dedicate them to the Brunei-Japan or Balikpapan-Japan leg of the system; this way they get extra time for loading whilst the return convoy proceeds to its final destination on the outbound voyage.

The scheme depicted details escort requirements according to the criteria developed by Allied operational research. I've applied the 'worst case' assumption that air cover isn't available, although in reality most if not all of the convoys' paths should receive heavy air cover. I propose to treat these as minimum requirements, and plan to have each convoy on the mainline accompanied by one or more ASW support groups for pouncing upon Allied submarines that threaten the convoy's line of advance.

The nightmare scenario is of an Allied SAG or carrier TF getting within striking distance of one of these convoys, since the upshot of a single attack might be fatal damage to Japan's oil transportation arrangements.

Last but not least I suspect that this shows clearly that I've got way too much time on my hands! [:D]

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RE: Nanshin! or the ramblings of Local Yokel

Post by Local Yokel »

Here are details of Japanese shipping losses in the period 7 Dec 1941 - 11 Apr 1942: a total of 52 vessels. I've sorted them by cause of loss, though I'm not sure whether this reveals anything significant.

ML Bungaree's MkXVII mines laid at Port Moresby accounted for 5 vessels, so she earned her keep for the Allied cause.

Dutch torpedoes have proved a good deal more effective than American, given the numbers fired; nothing surprising there.

Only 8 vessels have been lost to bombing attacks. I suspect this is due partly to luck and partly to the inexperience of Allied aircrews.

Raider Akagi Maru, with R. Adm Daigo aboard, went down S of Christmas Is. (IO) to the only effective anti-ship strike by carrier aircraft so far. Actually, at the time I thought I'd found an Allied SAG and was manoeuvring Yamada's light CV's towards it whilst the raider's floatplanes kept tabs on it. Unfortunately Akagi Maru couldn't run fast enough to stay clear of the British carrier(s). I declined the chance to engage the RN task force, as I'm hoping for a more favourable opportunity.

The worst casualties were the 2 light cruisers Naka and Isuzu. I shouldn't have exposed Naka as I did in the Andamans, but Isuzu's loss simply reflected the fact that sooner or later the Allied subs were bound to get lucky. Still, 2 CL's and 2 DD's represents an acceptably modest loss rate in surface warships for my grab of the SRA.

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RE: Nanshin! or the ramblings of Local Yokel

Post by Local Yokel »

I have not previously given details of what's been taking place in China, so here is a shot to show the state of things as at 11 April 1942.

Initially I had planned to strike down to Kanhsien from Nanchang, but was confronted in the wooded hex SW of Nanchang by a sizeable defending force. I then decided to find a more vulnerable spot at which to hit the enemy. This has led to Japanese operations focusing on Pucheng, and Japanese forces have now penetrated to a point 1 hex distant from the town on its SW side. Meanwhile, other substantial Japanese forces are closing with the Chinese units located to the NW/NE of Pucheng. I am attempting to pin these forces in the (mostly) non-wooded hexes in which they are currently located, hoping to destroy them in detail. However, the success of this exercise will depend upon whether I can seize Pucheng before substantial Chinese forces fall back to defend it.

A couple of notes on other parts of China:

A Japanese force can be seen in the wooded hex SW of Nanning. My opponent seems to have had second thoughts about an invasion of Indochina, but only after his incursion had activated the Vietnamese militia divisions.[:D] Some of these, stiffened by a regular IJA infantry unit, have entered the wooded hex to which the Chinese invaders retreated (they are present but not visible in this view), but neither side has tried to force the other out. Behind them, meanwhile, the Japanese are feverishly building up the defences of Hanoi and Haiphong.

Most of the Chinese guerillas in North Central China have been eliminated.

I voluntarily withdrew from Ichang at the outset, as I regarded it as a dangerously exposed salient likely to prove a source of trouble later. I see that Chinese units (4 of them so far) are now on the road from Ichang to Hankow. Irrespective of whether they strike for Hankow or Sinyang, they are assured of a warm welcome, as both these towns have been heavily fortified and are adequately garrisoned (I hope!).

I have deliberately tried to avoid committing myself to anything spectacular in China so far, as it's a theatre that is of secondary importance to me whilst I capture the SRA and SW Pacific areas and consolidate my hold on them. My immediate aim is to eradicate all hostile forces east of the line Nanchang-Swatow. If successful, this should provide me with a secure base for further operations ultimately directed towards Hengchow/Changsha when a suitable opportunity presents itself.

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RE: Nanshin! or the ramblings of Local Yokel

Post by Gen.Hoepner »

If you go for Darwin, i'd say go deeper. It's nice to to expand your defensive perimeter including Northern Oz, but remember that you do not wat to be flanked. My suggestion is: take darwin in the north (along with Whyndam, Derby and such) and use your paras to land at Daily waters, cutting his retreat path. Then, after you defeated his armies at Darwin with your divisions, order to your taks to shock-pursue. With this you should be able to destroy completely his northern army. March then till Alice Spring. It's so isolated that cannot be bombed with efficiency, even by the allies...and however, if they'r e bombing here they aren't attacking SRA!
But if i had to go for Darwin, i'd go also for Perth, as soon as my army in Darwin is unloaded. Grab everything in the west coast of Oz, which should be lightly defended. If you don't you'll expose yourself to a flanking advance on your right flank (Perth-exmouth-Timor) that will force you to run away...
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RE: Nanshin! or the ramblings of Local Yokel

Post by Local Yokel »

Interesting thoughts, General!

However, let me put forward some counter-arguments to the strategy you propose.

I agree that, having taken Darwin, the Japanese should advance into Australia's interior. If in the process they can eliminate Darwin's former defenders then well and good. I expect my opponent to be well aware of the risk that paratroops pose to his LOC, so I shouldn't be surprised to find both Katherine and Daly Waters garrisoned to frustrate such a coup.

However, I see no advantage in advancing as far as Alice. For the Japanese, it's at the end of a long stretch of road, with attendant supply penalties. For the Allies, it's at the end of a railway. Fighting at Alice plays to Allied logistical advantages. Digging in at Daly Waters reverses this: it would then be the Allies operating at the end of a slender supply line. With Alice as the most advanced Allied base, Darwin is beyond efficient bombing range.

As for Perth and W. Australia, it's possible to put together a large enough Japanese expeditionary force to be confident of taking it, but I'm not convinced that the gains justify the risks.

To start with, it's going to involve another major amphibious assault for which Japan doesn't start well-equipped. I'm expecting to take substantial shipping casualties in the attack on Darwin (he has 150+ bombers based there). They are going to be as bad, if not worse, in an attack upon Perth. Moreover, from Darwin the casualties have some hope of making it back to a friendly port and repair ships. From Perth, they won't.

The attack on Darwin receives the benefit of limited support from LBA. An attack on Perth doesn't. Guaranteeing the transports' safety requires the commitment of substantial naval assets, and both transports and SAG's will require air cover from KB. That draws KB away from the Central Pacific and unbalances the Japanese for too long. Geraldton is too small and too distant from Perth to offer an acceptable land-based alternative source of air cover.

However, assuming I am prepared to risk the losses that may be involved in securing Perth, what real advantages have I gained? I may have denied him a staging point for a thrust directed at Timor, but it's one to which I have to commit yet more defenders. It's also one I have to supply via a vulnerable sea LOC. Holding the west coast of Australia simply lengthens my defensive frontage. It dissipates the reserves I need to assure my hold on the Malay peninsula, Sumatra and the Sundas. Sooner or later he's likely to be coming for one of those, and frankly I'd rather face him in Timor or points west, where I shall enjoy a denser web of bases capable of supporting torpedo-equipped airstrikes. Indeed the preparations for the attack on Darwin themselves enhance this defensive web, thus killing 2 birds with one stone to Japan's advantage.

Look at it from the Allied viewpoint. If Japan establishes itself in Perth, what is the Allied response? Well, for starters they can send a besieging force west along an excellent railway line if they choose. Unlike the Japanese, their supplies to the front can't be sunk en route. If necessary such supplies can be supplemented via Albany, unless the Japanese commit to taking and defending this as well. Or they may decide to treat W. Australia as a self-imposed prison camp. Japanese troops can wait out the war there, whilst the Allies concentrate their ever-increasing forces on some other, more critical point of vulnerability.

For my money the capture of W. Australia is a jump too far for the Japanese come April 1942. I believe it leads to excessive dispersion of Japanese forces for too little reward. Maybe I'm suffering from cojones deficit disorder, but if so you'll be able tell me so when the Allies have comfortably established themselves in Koepang.
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RE: Nanshin! or the ramblings of Local Yokel

Post by Local Yokel »

Landings at Tarawa: the first Allied offensive

On a daily basis from mid-January 1942 the Japanese garrison of Tarawa have been dutifully submitting reports of American PBYs' daily reconnaissance overflights. Then, on 11 March, 6th Fleet HQ at Kwajalein begins to receive reports that a new, twin-boomed reconnaissance aircraft has also begun to snoop the atoll. American signals security is not as tight as it might be (hints in the (e)mail!), and gradually the Japanese come to suspect that some major operation directed towards the Gilberts may be afoot.

The problem for the Japanese is that there are few measures they can take to pre-empt such a move. Several units are preparing for garrison duty on Tarawa, but their infantry components are still filling out in the Home Islands. Furthermore, Tarawa is not regarded as a critical link in the perimeter and the Japanese are loath to commit major reinforcements on what is little better than a hunch about American intentions. Nevertheless, the garrison receives some limited additions and a minelaying group begins to ply between Truk and the Gilberts.

On 13th April a Type 0 reconnaissance seaplane of the 19th Chutai operating out of Betio sights a group of westbound Allied merchantmen some 360 miles ESE of Tarawa. The alarm bells ring all the way to Truk, for merchant ships on that course and in that location must be assumed have hostile intentions towards the Gilberts.

The Japanese immediately begin to activate their plans to meet this contingency. 2 chutai of Zeroes and 2 kokutai of land attack planes transfer to Maleolap, and units of the Imperial Navy are ordered to the Marshalls with all despatch. 1st Mobile Force with its heavy carriers receives orders to intervene if circumstances permit, but it will be several days before it can do so. Meanwhile the garrison on Tarawa braces itself.

The storm breaks with a punishing night time bombardment by an Anglo-US battleship-cruiser group on 14 April, followed by dive bombing attacks by US carrier aircraft:

Naval bombardment of Tarawa, at 84,95

Japanese aircraft
no flights

Japanese aircraft losses
E13A1 Jake: 2 destroyed

Allied Ships
CA Salt Lake City
CA Louisville
CA Indianapolis
BB Warspite
BB Idaho

Japanese ground losses:
2271 casualties reported
Guns lost 8

Airbase hits 15
Airbase supply hits 19
Port hits 3
Port supply hits 1
...

Day Air attack on 52nd Naval Guard Unit, at 84,95

Allied aircraft
F4F-3 Wildcat x 21
F4F-4 Wildcat x 19
SBD-3 Dauntless x 63

Allied aircraft losses
SBD-3 Dauntless: 3 damaged

Japanese ground losses:
149 casualties reported
Guns lost 2

Aircraft Attacking:
11 x SBD-3 Dauntless bombing at 2000 feet
18 x SBD-3 Dauntless bombing at 2000 feet
17 x SBD-3 Dauntless bombing at 2000 feet
17 x SBD-3 Dauntless bombing at 2000 feet

The American carrier task force is evidently operating in shallow waters some 240 miles ESE of Tarawa.

In the early morning hours of 15 April the bombardment group returns, but this time its efforts are ineffective, perhaps for want of ammunition:

Naval bombardment of Tarawa, at 84,95

Allied Ships
CA Salt Lake City
CA Louisville
CA Indianapolis
BB Warspite
BB Idaho

Japanese ground losses:
8 casualties reported

As dawn breaks an Allied invasion group is sighted approaching the atoll, and the Japanese bombers lift from the crushed coral of Maloelap's runway to assure them of a warm welcome:

Day Air attack on TF, near Tarawa at 84,95

Japanese aircraft
A6M2 Zero x 15
G4M1 Betty x 31

Japanese aircraft losses
G4M1 Betty: 1 destroyed, 17 damaged


Allied Ships
AP Bantam
AP Barnett, Torpedo hits 1
AP Arthur Middleton, Torpedo hits 3, on fire, heavy damage
AP President Coolidge
DD Sampson, Torpedo hits 1, on fire, heavy damage

Allied ground losses:
29 casualties reported
Guns lost 1

Aircraft Attacking:
3 x G4M1 Betty launching torpedoes at 200 feet
1 x G4M1 Betty launching torpedoes at 200 feet
3 x G4M1 Betty launching torpedoes at 200 feet
4 x G4M1 Betty launching torpedoes at 200 feet
4 x G4M1 Betty launching torpedoes at 200 feet
4 x G4M1 Betty launching torpedoes at 200 feet
4 x G4M1 Betty launching torpedoes at 200 feet
4 x G4M1 Betty launching torpedoes at 200 feet
3 x G4M1 Betty launching torpedoes at 200 feet

The invasion group seems hesitant in making its landfall, and the first assault troops of the US 27th division only begin to hit the beach late in the day. By this time, the Japanese mines have begun to take their toll:

TF 1036 encounters mine field at Tarawa (84,95)

TF 1036 troops unloading over beach at Tarawa, 84,95

Allied Ships
AP Mormacdove, Mine hits 2, on fire, heavy damage
DD Sampson, on fire, heavy damage

Allied ground losses:
30 casualties reported

Coastal Guns at Tarawa, 84,95, firing at TF 1036
9 Coastal gun shots fired in defense.
Allied Ships
DD Smith

Allied ground losses:
184 casualties reported

--------------------------------------------------------------------------------
Ground combat at Tarawa

Japanese Bombardment attack

Attacking force 4025 troops, 19 guns, 0 vehicles, Assault Value = 126

Defending force 1565 troops, 27 guns, 3 vehicles, Assault Value = 77

Japanese ground losses:
9 casualties reported
Guns lost 1

Allied ground losses:
2 casualties reported
Guns lost 1

--------------------------------------------------------------------------------
Ground combat at Tarawa

Allied Shock attack

Attacking force 1561 troops, 26 guns, 3 vehicles, Assault Value = 77

Defending force 4986 troops, 17 guns, 0 vehicles, Assault Value = 126

Allied max assault: 70 - adjusted assault: 1

Japanese max defense: 105 - adjusted defense: 54

Allied assault odds: 0 to 1 (fort level 2)

Allied ground losses:
519 casualties reported
Guns lost 7
Vehicles lost 2

The transport group lying off Tarawa is reported as containing only 8 ships of any size, but there's another transport group coming in some 60 miles astern. The presence of President Coolidge is a surprise, but not an unwelcome one. If she's carrying the main body of 27th Division she will take a time to unload, and if his assault troops come ashore in penny packets they will be in real danger of piecemeal destruction.

Tarawa remains well stocked with supplies, but really the defenders' AV is insufficient for me to have any confidence in their ability to hold.

Even if I lose the atoll I expect him to pay a stiff price in high value troopships. This is going to be an interesting battle.
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RE: Nanshin! or the ramblings of Local Yokel

Post by Local Yokel »

Day Two at Tarawa - 16 April 1942

Transport Mormacdove continues to operate as an involuntary minesweeper

TF 1036 encounters mine field at Tarawa (84,95)

TF 1036 troops unloading over beach at Tarawa, 84,95


Allied Ships
AP Mormacdove, Mine hits 1, on fire, heavy damage
DD Smith
AP President Coolidge, Mine hits 1, on fire


Allied ground losses:
19 casualties reported

Coastal Guns at Tarawa, 84,95, firing at TF 1036
16 Coastal gun shots fired in defense.
Allied Ships
DD Smith

Japanese ground losses:
10 casualties reported

Allied ground losses:
112 casualties reported

I-175 takes a shot at an escort in the retiring bombardment group - and misses

Sub attack at 89,98

Japanese Ships
SS I-175

Allied Ships
DD Ellet
DD Drayton
DD Morris
DD Walke
DD O'Brien
CA Louisville
CA Indianapolis
BB Idaho

Sub attack near Tarawa at 84,95

Japanese Ships
SS RO-64

Allied Ships
AP Barnett
DD Smith

Allied transports also start to unload at Makin. There are no defenders to oppose them.
--------------------------------------------------------------------------------
TF 1079 troops unloading over beach at Makin, 84,93

Allied ground losses:
69 casualties reported

Meanwhile, a series of task forces arrive at Tarawa. Japanese coastal submarines engage them whilst the mines claim further casualties:
--------------------------------------------------------------------------------
TF 1036 encounters mine field at Tarawa (84,95)

TF 1036 troops unloading over beach at Tarawa, 84,95

Allied Ships
DD Smith

Coastal Guns at Tarawa, 84,95, firing at TF 1036
10 Coastal gun shots fired in defense.
Allied Ships
DD Smith

Allied ground losses:
46 casualties reported

--------------------------------------------------------------------------------
Coastal Guns at Tarawa, 84,95, firing at TF 1038
--------------------------------------------------------------------------------
TF 1038 encounters mine field at Tarawa (84,95)

TF 1038 troops unloading over beach at Tarawa, 84,95

--------------------------------------------------------------------------------
TF 1079 troops unloading over beach at Makin, 84,93

Allied ground losses:
28 casualties reported

--------------------------------------------------------------------------------
Coastal Guns at Tarawa, 84,95, firing at TF 1094
--------------------------------------------------------------------------------
TF 1094 encounters mine field at Tarawa (84,95)

TF 1094 troops unloading over beach at Tarawa, 84,95

6 Coastal gun shots fired in defense.

Allied ground losses:
55 casualties reported

--------------------------------------------------------------------------------
TF 1137 encounters mine field at Tarawa (84,95)

TF 1137 troops unloading over beach at Tarawa, 84,95

Allied Ships
AK Steel Traveler, Mine hits 1
AK Steel Scientist, Mine hits 1, on fire


Allied ground losses:
10 casualties reported
Vehicles lost 1

Coastal Guns at Tarawa, 84,95, firing at TF 1137

Allied ground losses:
28 casualties reported
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Sub attack near Tarawa at 84,95

Japanese Ships
SS RO-64

Allied Ships
AK Bintoehan, Torpedo hits 1, on fire

Land attack planes from Maloelap join the party. Where is the expected US CAP?
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Day Air attack on TF, near Makin at 84,93

Japanese aircraft
A6M2 Zero x 7
G4M1 Betty x 12

No Japanese losses

Allied Ships
AK Empire Rowan, Torpedo hits 2, on fire, heavy damage
AK Elna, Torpedo hits 3, on fire, heavy damage


Allied ground losses:
10 casualties reported

Aircraft Attacking:
2 x G4M1 Betty launching torpedoes at 200 feet
3 x G4M1 Betty launching torpedoes at 200 feet
3 x G4M1 Betty launching torpedoes at 200 feet
4 x G4M1 Betty launching torpedoes at 200 feet

--------------------------------------------------------------------------------
Day Air attack on TF, near Tarawa at 84,95

Japanese aircraft
A6M2 Zero x 6
G4M1 Betty x 3

Japanese aircraft losses
G4M1 Betty: 1 damaged

Allied Ships
AP President Coolidge, Torpedo hits 2, on fire, heavy damage (Sinks)

Aircraft Attacking:
3 x G4M1 Betty launching torpedoes at 200 feet
--------------------------------------------------------------------------------
Day Air attack on TF, near Tarawa at 84,95

Japanese aircraft
G4M1 Betty x 3

No Japanese losses

Allied Ships
AK Bintoehan, on fire, heavy damage

Aircraft Attacking:
3 x G4M1 Betty launching torpedoes at 200 feet
--------------------------------------------------------------------------------
Day Air attack on TF, near Tarawa at 84,95

Japanese aircraft
G4M1 Betty x 6

Japanese aircraft losses
G4M1 Betty: 1 damaged

Allied Ships
AK Sagadahoc, Torpedo hits 3, on fire, heavy damage

Allied ground losses:
28 casualties reported
Vehicles lost 2

Aircraft Attacking:
2 x G4M1 Betty launching torpedoes at 200 feet
4 x G4M1 Betty launching torpedoes at 200 feet

Fighting on the beachhead continues...
--------------------------------------------------------------------------------
Ground combat at Tarawa

Japanese Bombardment attack

Attacking force 4032 troops, 16 guns, 0 vehicles, Assault Value = 132

Defending force 3202 troops, 25 guns, 8 vehicles, Assault Value = 26

Allied ground losses:
10 casualties reported
Vehicles lost 1
--------------------------------------------------------------------------------
Ground combat at Tarawa

Allied Shock attack

Attacking force 2602 troops, 25 guns, 7 vehicles, Assault Value = 25

Defending force 5302 troops, 19 guns, 0 vehicles, Assault Value = 132

Allied max assault: 18 - adjusted assault: 2

Japanese max defense: 117 - adjusted defense: 37

Allied assault odds: 0 to 1 (fort level 2)

Japanese ground losses:
55 casualties reported
Guns lost 2

Allied ground losses:
156 casualties reported
Guns lost 3
Vehicles lost 1

...and Makin falls to a Raider battalion
--------------------------------------------------------------------------------
Ground combat at Makin

Allied Shock attack

Attacking force 630 troops, 0 guns, 0 vehicles, Assault Value = 22

Defending force 0 troops, 0 guns, 0 vehicles, Assault Value = 0

Allied max assault: 26 - adjusted assault: 14

Japanese max defense: 0 - adjusted defense: 1

Allied assault odds: 14 to 1 (fort level 0)

Allied forces CAPTURE Makin base !!!
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Local Yokel
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RE: Nanshin! or the ramblings of Local Yokel

Post by Local Yokel »

Tarawa: all is quiet now.

This was a battle that ended not with a bang but a whimper.

Although the second day's shock attack had yielded a derisory AV of 25 for the Allies, I had expected them to persevere in their efforts to get a decent amount of firepower ashore and into action. But it was not to be. Came the third day of the battle, there remained only a couple of submarines in the offing (presumably evacuating the shocked survivors), and about 10 vehicles littering the foreshore, apparently still occupied by their crews. I imagine they are probably Stuarts. I don't have any anti-tank guns amongst my defenders, so I'm inclined to let these invaders wither for a few days.

The retiring transport groups are being harassed (ineffectually) by my submarines, but it seems that the curtain has come down on my opponent's first attempt to claw his way back across the Pacific.

In his emails he admits that he made several errors that had fairly disastrous consequences. First, he failed to notice that Maloelap is a level-4 airfield from which torpedo-armed land attack planes could reach Tarawa with fighter escort. Second, he failed to cater for the possibility that Tarawa's waters were mined, and brought no MSW's or DMS's with him. Third, he apparently intended to fly LRCAP over his transports but omitted to set the necessary orders. I suspect that in addition he was using far too few transports, at least one of which (Pres. Coolidge) wasn't fit for purpose. The consequence seems to have been that his invasion group would have needed several days to unload, and that those assault troops that made it to the beach did so in drabs and drabs, and were cut down by a small number of defenders as a result.

I know that the US 27th ID was the main component of his assault force, but I have no idea how much of it still remained on board the Coolidge when it went down. I've seen no dramatic jump in the Allied troop loss total, but I don't know whether troops who go down with a ship are reflected in that total. If they are, then he's got away lightly.

The torpedo-toting land attack aircraft were murderous, and accounted for a significant proportion of his invasion group. Had he persisted on day 3, 1st Mobile Force was sitting within torpedo-capable range to the NW of Tarawa, and I suspect there might have been a more comprehensive slaughter of his ships. His carriers never approached to within less than 240 miles of Tarawa (to the SE of the atoll), so the likelihood is that the Mobile Force would have remained undetected. I suspect that even if he had successfully mounted CAP cover over his transports it would have been overwhelmed by a succession of escorted strikes from Maloelap and the Mobile Force.

Just to make his discomfiture complete, it apears that my opponent failed to notice that he had given 'retirement allowed' orders to an Australia-bound troop convoy. Having unloaded on Australia's east coast it blithely went on its way back to West Coast US until it was spotted by a Japanese flying boat midway between the Lower Solomons and New Caledonia. As this happened simultanously with the his Tarawa op., I assumed this was a coordinated operation aimed at Koumac or Espiritu Santo (can never think of it as 'Luganville'). Both Lunga and Noumea are playing host to a kokutai of land attack planes apiece, and they piled in with gusto, with the result that the returning convoy was virtually annihilated.

I've tried to console my opponent by pointing out that Tarawa was very much a 'learning experience' for the Allies IRL, and if he takes the lessons to heart I can expect the next assault to be a good deal more determined and proficient. Meanwhile I'm relieved to have bought myself some time in which to beef up my Pacific bulwark.
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Cuttlefish
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RE: Nanshin! or the ramblings of Local Yokel

Post by Cuttlefish »

Nice summary of the battle. Learning how to mount an effective amphibious attack is one of the harder things to do in this game, I think. Perhaps your opponent can think of this as his Dieppe - a disaster, but one with valuable lessons. And as you said, you gain time.

By the way, I don't think troops lost aboard ship do show up in the troop loss totals. I once lost an entire division at sea (the memory remains painful) and my loss totals did not change at all.
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Local Yokel
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Location: Somerset, U.K.

RE: Nanshin! or the ramblings of Local Yokel

Post by Local Yokel »

Thanks, Cuttlefish! I had a suspicion that troops sinking with a ship were not indicated in the scoreline. I saw no message indicating rescue of survivors, so the extent of his losses has to remain a matter for speculation. Wishful thinking makes me want to conclude that 27th US ID will be hors de combat for a few months, but it would probably be rash for me to plan on that assumption.
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Local Yokel
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Joined: Sun Feb 04, 2007 12:55 pm
Location: Somerset, U.K.

RE: Nanshin! or the ramblings of Local Yokel

Post by Local Yokel »

I have a question (or three). I am planning a major amphibious operation in the Indian Ocean where I expect the target to be heavily defended with artillery. I have to decide what to put into the invasion transport group to neutralise the defending guns. I understand that battleships can be incorporated into an escort TF, so it would be possible to build the invasion TF to include such ships. Does one then keep the invasion TF as an escort TF, or can one change it into a transport TF so as to be sure it will unload when it reaches the target base?

Also, is it actually a good idea to put a battleship into the invasion TF to absorb the defenders' fire? I have to assume I shall be opposed by torpedo bombers, and that some of them are sure to get through such CAP as I can put up, so BB's remaining in the target hex will be vulnerable. Would it be better for me to put all participating BB's into bombardment or surface action groups rather than the transport group?

Third, my experience suggests that bombardment groups tend to concentrate on only part of the target's assets, perhaps leaving the defenders' airfields and/or coastal artillery untouched. To counter this I am contemplating the use of multiple bombardment groups. Any thoughts on the optimum size/composition of such groups? My fast BB's and CA's should be able to get in and out overnight without leaving themselves within torpedo attack range come daybreak, but not the slow BB's.
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Yakface
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RE: Nanshin! or the ramblings of Local Yokel

Post by Yakface »

1.  Yes - make up the invasion TF as a escort with the BB included and then convert to transport (IIRC escort TF's don't unload)
 
2.  Don't think anyone can give a whole load of advice on this one.  The BB will be useful in the invasion fleet, drawing fire and delivering it.  My experience is that a BB in a bombardment TF's are better at doing damage but BB in the transport is better at drawing fire.  It's a matter of judgement and only really for you to say whether you want to risk it considering you are likely up against TB's.  Personally I would only include it if the fire from the shore would otherwise be severe.  Otherwise CA's may be a better bet.
 
3. Not sure it matters whether ships are grouped together or split up for bombardments (other than the normalising effect of lots vs few).  I'd probably go for 4 bombardment platforms (BB or CA) in each, but no idea whether that's right or not. 
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