Atoll defenses

[AirGriff]

I'm playing my first IJ game in a pbem, and I just got walloped at Canton Island. My worthy opponent overwhelmed my one and a half Nav Guards, an RF unit and some base forces. FL was at 3. I had good supply, though. He brought a US division and a regiment, so my guys were way outnumbered and I'm not surprised at the result. But it's only May of '42 and I wasn't expecting this kind of push back this early. If some of you experienced IJFB's could elaborate on recipes for the right cocktail on atolls it would be much appreciated!

[msieving1]

The opposition can always come up with enough force to take an isolated atoll.  You need additional bases within bomber range or aircraft carriers for support.

[AW1Steve]

The only way to defend a small atoll is to sink his ships while the troops are still on them. Period. You are limited to 6,000 troops. He's not. He can attack with 5 divisions, and as long as he evacuates all but 6k, he's fine. I don't even bother to garrison such atolls , excepting for whatever base and CD units I'm willing to lose (and hopefully bleed him a bit). That's what tenders are for. Refuel and repair your ships and subs, support your PA aircraft then when he's coming , evacuate them. Maybe keep a fighter squadron to discourage "nuisance" air raids , but that's it. Let him take the island. Then you go back and re-take it. Unless you can surround the island with planes, ships and best of all carriers, you can't hold it. You can simply make it bloody for him.

[mind_messing]

You don't garrison atolls in the hope of holding them, you garrison them so that your opponent has to bring the toolbox (carriers, battleships, amphibious ships) to take the atoll, rather than on the cheap (paradrop or sub invasion).

Exposed places like Canton can't be held against a determined Allied attempt on them, without IJN carriers being commited.

The right "atoll cocktail" is enough to hold against a paradrop or a sub invasion. Any more is just going to waste, as the Allies can (and will) gain local superiority for atoll invasions.

[jmalter]

I agree w/ mind_messing - IJ conquests in the Marshalls & points east or south are only going to be a speed-bump to Allied re-conquest.

It would take too much time to commit serious forces to this area, in an attempt to build the Marshalls into a fully-manned, mutually-supporting network of max-capacity airfields. It's probably a mistake to increase the port/airfield capacities here, those increased sizes will only lighten the burden on the Allies as they move into those islands.

Far better to devote your forces to digging in & defending the Marianas, Truk, & whatever of the Solomons you've occupied.

But you might have some fun deploying minefields at some advanced bases, while covering the area w/ long-range NavS & patrolling w/ submarines.

[AirGriff]

Thanks guys. Good stuff. That's a little surprising to me. As a former AFB, I typically avoided the atolls and pushed up the NG coast as I'd heard horror stories a-plenty of atoll assaults gone horribly bad. Makes me wonder if I shouldn't have gone the Nimitz preferred route in games past.

[jmalter]

It's easy to crunch an atoll, but you must come big, include lots of supply to unload on days subsequent to the initial assault, & load your overstacked combat units back onto their transports as soon as combat is done, for R&R & planning for their next target. An atoll can cope w/ as much as 15% troop overstack before the supply spoilage gets horrible.

When invading an atoll, you want to arrive in the hex the day before w/o unloading, then unload on D-day - to get all 4 stages of amph unloading before combat. Atoll invasion is an automatic Shock attack. Spoilage occurs after the land combat phase - you must have add'l supply unloading on D+1.

[Yaab]

How about this:

- an infantry regiment with very high exp (70-90 range) from a division that has light tanks in TOE or additional field guns, 100% prepared - 4500 stacking cost
- a mortar regiment (the big one with 36 mortars) --- 530 stacking cost,thus you could put two such regiments on the atoll --- 72 mortars!
-an IJA AA defense batalion (570 stacking) - 8 DP guns + 2 sound detectors
- high fort level, supply + fighters

Total stacking : 6130

Could be interesting.

[mind_messing]

ORIGINAL: Yaab

How about this:

- an infantry regiment with very high exp (70-90 range) from a division that has light tanks in TOE or additional field guns, 100% prepared - 4500 stacking cost
- a mortar regiment (the big one with 36 mortars) --- 530 stacking cost,thus you could put two such regiments on the atoll --- 72 mortars!
-an IJA AA defense batalion (570 stacking) - 8 DP guns + 2 sound detectors
- high fort level, supply + fighters

Total stacking : 6130

Could be interesting.

Multiply that by any number of atolls and you quickly run out of troops, mortars and AA. What's the worth of throwing that much on to a few atolls when the Allies have plenty of other atolls with which to by-pass your garrisons?

Your stacking maths doesn't take account aviation support either, which means you'll probably have to forget your mortars if you want to deploy some fighters instead.

ORIGINAL: jmalter

I agree w/ mind_messing - IJ conquests in the Marshalls & points east or south are only going to be a speed-bump to Allied re-conquest.

It would take too much time to commit serious forces to this area, in an attempt to build the Marshalls into a fully-manned, mutually-supporting network of max-capacity airfields. It's probably a mistake to increase the port/airfield capacities here, those increased sizes will only lighten the burden on the Allies as they move into those islands.

I disagree there, there's a fair few bases in the Marshalls that need developing. Kusaie and Ponope are two excellent investments, as they'll give you good supporting airbases in the rear and some defensive depth between the Marshalls and Truk.

Mili is another base well worth the investment. There are only two 30,000 limit bases in the Marshalls (the rest are all 6k), Ailinglaplap and Mili.

Ailinglaplap is a fairly poor investment as it's a 0(0) port and 0(2) airbase, and you've Roi-Namur 3 hexes away that's already a better base.

Mili, however, is much better. 0(1) port and 1(2) airbase, and you even get very good CD gun unit for free, complete with some 15cm guns. With a 30k troop limit, it can be quite the airbase and can host a very stout garrison. Even better, it's right in the way of any Allied island hopping campaign up the Gilbert Islands.

ORIGINAL: AirGriff

Thanks guys. Good stuff. That's a little surprising to me. As a former AFB, I typically avoided the atolls and pushed up the NG coast as I'd heard horror stories a-plenty of atoll assaults gone horribly bad. Makes me wonder if I shouldn't have gone the Nimitz preferred route in games past.

Someone else on here (can't remember who) phrased it just right:

You can conduct hundreds of amphibious invasions moving from Rabual to the Philippines, or you can be on Japan's doorstep with as little as a dozen moving in CentPac.

[AirGriff]

Are there any CD/DP gun units for the IJ offered in '42? The only one I've seen is the Wake CD unit. From what I understand of all the spreadsheets, none of the standard arty units carry DP guns. Is that correct? If so, my guys better dig deeper holes.

[Yaab]

Maybe Combined 8th SNLF (unit TOE ID 4273)? It should combine in about 350 days after the game start.

[mind_messing]

ORIGINAL: AirGriff

Are there any CD/DP gun units for the IJ offered in '42? The only one I've seen is the Wake CD unit. From what I understand of all the spreadsheets, none of the standard arty units carry DP guns. Is that correct? If so, my guys better dig deeper holes.

Some Base Force and Special Base force units start off with some DP guns, or get a TOE upgrade adding some, but the Wake CD unit is the only true mobile CD unit Japan gets until later in the war.

[obvert]

Here is an example that went well for the defenses at Canton Is. I had a little bit more than most players put out here. I think the garrison unit might have been one of the ones that withdraws, so I was happy to put it out here.

http://www.matrixgames.com/forums/fb.asp?m=3212198

The key here is not as much the units involved, but the amount of preparation for the attack. There were no air strikes or extended bombardments.

Later Jocke got it figured out. He plastered the garrison at Wake for days and by the time he landed it wasn't much of a fight.

This is also the thread Jocke started after the failed landing to get advice. It has a LOT of good advice which he used to good effect later. [:)]

http://www.matrixgames.com/forums/tm.asp?m=3212274&mpage=1

[obvert]

ORIGINAL: mind_messing

ORIGINAL: AirGriff

Are there any CD/DP gun units for the IJ offered in '42? The only one I've seen is the Wake CD unit. From what I understand of all the spreadsheets, none of the standard arty units carry DP guns. Is that correct? If so, my guys better dig deeper holes.

Some Base Force and Special Base force units start off with some DP guns, or get a TOE upgrade adding some, but the Wake CD unit is the only true mobile CD unit Japan gets until later in the war.

The big base forces get 12 x 12.7cm DP guns and I think 10 x 8cm guns with TOE upgrades by 4/43, and two SNLF units compile just before that into a wicked CD gun unit that also has 60 AV with it's 14cm guns. There are a lot of other units that have a few smaller guns and more get big guns in 44. There is one more mobile unit too but I forget it's name. By the time the Marianas or Bonins are hit I am able to have good CD guns on every base in those chains.