Normandy Invasion Messed Up?

Gary Grigsby’s War in the West 1943-45 is the most ambitious and detailed computer wargame on the Western Front of World War II ever made. Starting with the Summer 1943 invasions of Sicily and Italy and proceeding through the invasions of France and the drive into Germany, War in the West brings you all the Allied campaigns in Western Europe and the capability to re-fight the Western Front according to your plan.

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cfulbright
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Joined: Tue May 06, 2003 11:12 pm

RE: Normandy Invasion Messed Up?

Post by cfulbright »

Repeated testing of the 9th AF with the the same air directives as 2 TAC showed that USAAF Groups are 'squishier' than RAF squadrons and lose morale faster. Even with very low aircraft losses. I see no good reason for this except some mathematical simplification in the game's code. Thus, USAAF groups were 'squadronized' by a Python script. This fixes the issue. USAAF organization was flight-squadron-group, so this feels reasonably accurate in a historical sense.

I've notice this, and wondered why. It may, indeed, be a math issue in the code, where larger numbers have a disproportinate likelihood of suffering damage or loss. For example, if you move an infantry division from Oran to Naples in short bursts, you have a good chance of getting all the way there without naval attrition, whereas if you do the entire voyage in one click you almost certainly will suffer attrition. I believe one of the designers confirmed this to me. The same might be true for 75-aircraft air units v. 16-aircraft units.

Cary
GeneralDad
Posts: 112
Joined: Sun Jan 07, 2018 1:22 am

RE: Normandy Invasion Messed Up?

Post by GeneralDad »

"I've notice this, and wondered why. It may, indeed, be a math issue in the code, where larger numbers have a disproportionate likelihood of suffering damage or loss. For example, if you move an infantry division from Oran to Naples in short bursts, you have a good chance of getting all the way there without naval attrition, whereas if you do the entire voyage in one click you almost certainly will suffer attrition. I believe one of the designers confirmed this to me. The same might be true for 75-aircraft air units v. 16-aircraft units." Cary

What was interesting to me was that the 75 plane units were suffering more morale loss even with proportionally lower combat aircraft losses and damaged planes. The morale hit to the P-47 groups was thus harder even with miniscule losses. I was losing 3-4 groups of P-47s in 9th AF per turn to morale. Make them 'squadrons', take the same combat losses and lose almost no squadrons to morale & when you do have to rest one squadron it is fewer planes off line. I will try the shorter burst naval movement - maybe the same issue, a simplification in the math of the probabilities in the code.

The game coding problem is probably something like this: the designers want the game to run fast. But, floating point math and especially division is slower than integer math. So these issues are at risk of getting into games due to the possible use of integer math where floating point would be more accurate.

The Python script works on the air group csv, then reassigns the pilots in the pilot csv. The editor seems to sometimes put too many planes in a 'squadron' when it is closed, more than the number of pilots, but the game also seems to correct it at turn 1 end. You wind up with unused planes overloading some bases only on T1; but as they don't seem to get used they don't appear to do any significant harm.

Gen Dad.



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cfulbright
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RE: Normandy Invasion Messed Up?

Post by cfulbright »

The Python script works on the air group csv, then reassigns the pilots in the pilot csv. The editor seems to sometimes put too many planes in a 'squadron' when it is closed, more than the number of pilots, but the game also seems to correct it at turn 1 end. You wind up with unused planes overloading some bases only on T1; but as they don't seem to get used they don't appear to do any significant harm.

I like it! Knowing that the USAAF had squadrons within groups, I've always wondered why this game used groups for the USAAF, squadrons for the RAF/CW, and then even has those add little 4-plane units for the LW.

I'm sure there's somebody out there who will look up the USAAF squadrons within your subgroups.

Cary
GeneralDad
Posts: 112
Joined: Sun Jan 07, 2018 1:22 am

RE: Normandy Invasion Messed Up?

Post by GeneralDad »

I like it! Knowing that the USAAF had squadrons within groups, I've always wondered why this game used groups for the USAAF, squadrons for the RAF/CW, and then even has those add little 4-plane units for the LW.

I'm sure there's somebody out there who will look up the USAAF squadrons within your subgroups.

If you know Python and Pandas then I could post the code on Github. Alt, I could post the csv files if you are interested.

Gen Dad.
GloriousRuse
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RE: Normandy Invasion Messed Up?

Post by GloriousRuse »

The Germans aren't running any NPs in those photos, so it's all port projection. Incidentally, the likelihood of getting hit for EVERY SHIP is something like Rand(180) < X = hit, where X is related to sea control, interdiction levels, etc. This means going through a "5" interdiction can be vicious when you consider how many troop ships are in a division.

As for the AA, it doesn't necessarily get rolled into the hex it fires at (your map would literally be covered with corridors three thick of "AA shot here" as all the adjacent AA to the flight path kicked in), instead it gets assigned to the closest relevant combat event.
cfulbright
Posts: 2782
Joined: Tue May 06, 2003 11:12 pm

RE: Normandy Invasion Messed Up?

Post by cfulbright »

I'm not a programmer. I could probably do it in the CSV's. Like you, I used the editor to modify my favorite campaign, so I don't think I could use your CSV.

Cary
GeneralDad
Posts: 112
Joined: Sun Jan 07, 2018 1:22 am

RE: Normandy Invasion Messed Up?

Post by GeneralDad »

The Germans aren't running any NPs in those photos...

When I check air battles, there are German interdiction battles over the Seine Bay - so I think that they are running NPs. MY first screen shot had no port damage - I did not realize how important it was. Getting much better, though. Here is the latest T4 just post-invasion air result. I now have Cherbourg and Le Harve at 100% damage. IMO: amphib losses are still too high.

Gen Dad

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GeneralDad
Posts: 112
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RE: Normandy Invasion Messed Up?

Post by GeneralDad »

Success perhaps - added some extra RAF Bomber Command Lancasters to their existing NP AD and this suppressed German Naval interdiction values to 0-2 rather than 2-4. The Amphibs still lose too many points but now I have command of the sea to a meaningful extent.

It seems counter-intuitive to me that cutting air superiority made little difference; but adding more Lancasters with mines from RAF Bmr seems to win the day. I would have thought that the way to suppress the other guy was to intercept his air missions.

Now all I need to do is figure out how to not get stuck in Normandy - how to attack those big German stacks.

Thanks for all the help.

Gen Dad.

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