Japanese Infiltration Tactics

[herwin]

I'm working on a model of in-hex combat for the successor to WitP-AE. The hex and time scales of WitP mean that the game avoids the problems with modelling battles seen in most wargames (due to small hexes and long turns), but forces the analyst to come up with some way of representing the state of affairs within the hex. The easiest solution would be to treat battles as changing the proportion of the hex held by each side, but that runs into issues with how control of installations and bases is modelled and how to deal with Japanese infiltration tactics.

Japanese infiltration tactics drive boardgame designers crazy. The Japanese usually avoided stand-up battles and instead infiltrated their way forward, and it took the Allied armies some time before they adapted. Assuming WitP were modified to represent hex control as a percentage, what you would see during a Japanese offensive (in close terrain) is that the Japanese gradually infiltrate throughout the hex, increasing their percentage control, using local attacks as necessary, until the Allied troops hold only their positions. Then, unless the Allied troops can stay in supply, they're forced to retreat into a hex where the Japanese don't control the countryside. (By the way, there are no zones of control for the Japanese--they can move freely through any close hex not firmly held by the Allies, supply throw being the major constraint.)

Percolation theory suggests a way of modelling this. (See wikipedia.) For a given category of terrain, there is a threshold troop density in the front lines, below which the Japanese are free to percolate through the front line and above which, the Allies can hold the hex. (In fact, it works the other way, too, just not as dramatically.) This troop density threshold involves target acquisition range (most important), weapon range, and weapon effectiveness in the hex terrain. So basically, there is a minimum garrison (defined in terms of these three factors) that can hold a line in a given hex. If the garrison falls below that value, the most it can do is hold its positions, bases (maybe), and installations (maybe) using all-around defence.

What should the troop density threshold be for WitP-AE's 40-mile hexes? I think it should be defined in terms of rifle-caliber and anti-tank rounds per minute per meter of front, since those were the primary direct-fire weapons categories.

Some examples: a modern mechanised battalion is able to hold a front of 3 miles and screen up to 9 against a mechanised opponent in rolling terrain. In WWII, a standard infantry division was able to hold 5 miles in strength and screen up to 20-25 in similar terrain.

[Barb]

While a nice idea it could work in clear hexes only. There is no way one could have continuous line in jungle! The same for mountains - there are hills/points that rule the terrain. This you will occupy with your units, elsewhere you will use patrols or nothing at all.

The whole infiltration tactics was to go around those guarded spots and position roadblocks on enemy supply lines. If the enemy is dependend upon land resupply - he will retreat - again going around the roadblock. If enemy isnt dependend upon land resupply, infiltration tactics isnt effective - the side with less airdropped supplies will retreat.

[herwin]

ORIGINAL: Barb

While a nice idea it could work in clear hexes only. There is no way one could have continuous line in jungle! The same for mountains - there are hills/points that rule the terrain. This you will occupy with your units, elsewhere you will use patrols or nothing at all.

The whole infiltration tactics was to go around those guarded spots and position roadblocks on enemy supply lines. If the enemy is dependend upon land resupply - he will retreat - again going around the roadblock. If enemy isnt dependend upon land resupply, infiltration tactics isnt effective - the side with less airdropped supplies will retreat.

The point of the percolation threshold is that it's a way of quantifying what you describe. In any terrain, the troop density needed to create a continuous line is a threshold between infiltration tactics and conventional tactics, and can be used to choose the appropriate combat engine.

[treespider]

The Operational Combat Series has a nice way of capturing this IMO through the use of Troop Quality(TQ). In OCS each unit is assigned a TQ value of 0-5. When combat is initiated between two sides the respective TQ's are compared and the TQ difference is added/subtracted from the eventual Combat Results die roll.

In addition every combat has the potential for "Surprise". The difference in TQ also affects this chance. "Surprise" can simply be a reflection of much better tactics or true surprise.

So as an example a TQ 5 unit attacking a TQ 0 unit would roll 2 dice. First they would determine whether surprise was achieved by adding +5 to the surprise roll - the TQ 5 unit will surprise the TQ 0 unit on a roll of 5 or more with 2 dice adding 5 to the DR. If surprise is achieved the odds column is shifted 1-6 columns in the surprising units favor.

Then on the CRT the final DR is modified with a +5 DR modifier again...

So to reflect the early war Japanese use and success with infiltration tactics, The Japanese TQ would be rated higher than the Allied TQ. Then as the war progressed the Allied TQ would rise to reflect better training and experience in coping with the Japanese Infiltration tactics.

In essence the TQ 0 unit would not cover its flanks nor defend against infiltration attacks...whereas a TQ 5 unit would.

[herwin]

ORIGINAL: treespider

The Operational Combat Series has a nice way of capturing this IMO through the use of Troop Quality(TQ). In OCS each unit is assigned a TQ value of 0-5. When combat is initiated between two sides the respective TQ's are compared and the TQ difference is added/subtracted from the eventual Combat Results die roll.

In addition every combat has the potential for "Surprise". The difference in TQ also affects this chance. "Surprise" can simply be a reflection of much better tactics or true surprise.

So as an example a TQ 5 unit attacking a TQ 0 unit would roll 2 dice. First they would determine whether surprise was achieved by adding +5 to the surprise roll - the TQ 5 unit will surprise the TQ 0 unit on a roll of 5 or more with 2 dice adding 5 to the DR. If surprise is achieved the odds column is shifted 1-6 columns in the surprising units favor.

Then on the CRT the final DR is modified with a +5 DR modifier again...

So to reflect the early war Japanese use and success with infiltration tactics, The Japanese TQ would be rated higher than the Allied TQ. Then as the war progressed the Allied TQ would rise to reflect better training and experience in coping with the Japanese Infiltration tactics.

In essence the TQ 0 unit would not cover its flanks nor defend against infiltration attacks...whereas a TQ 5 unit would.

That's how they handle it in OCS Burma. (The game box is about a foot away as I write.) They still found it hard to model the cohesion that Japanese troops actually had. My youngest indicates the same problems show up if you try to model the Russian Civil War.

[herwin]

BTW, if you have Totaler Krieg, read Steve Kosakowski's article in the Reference Book about the Designer's Deepest Secrets. His points look to be valid for WitP. The Japanese player should have only one shot at victory, by crippling the Pacific Fleet as it advances through the Central Pacific, taking India, taking China, taking Russia, or by cutting Australia and New Zealand off from America. Focus should be key--the lack of focus seen in reality should be the real error.