Bogging and Immobilized: is it right?

[Vanir Ausf B]

Interestingly enough the Tiger I was worse with 1.05kg/cm² and the T-34/85 had just 0.81 kg/cm2.

I don't know what hidden number CMBN uses, but CMBB uses .97 (13.9 psi) for the Tiger I.

[JonS]

For the data driven amongst you, try and obtain a copy of D. Rowland, "Tracked Vehicle Ground Pressure and its Effect on Soft Ground Performance", 1972 and "A Review of Vehicle Design for Soft Ground Operation." The first deals mainly with late-WWII vehicles, but includes references up to 1970. The later deals with WWI, WWII, and Cold War wheeled and tracked vehicles up till about the mid-1970s.

[winkelried]

For the data driven amongst you, try and obtain a copy of D. Rowland, "Tracked Vehicle Ground Pressure and its Effect on Soft Ground Performance", 1972 and "A Review of Vehicle Design for Soft Ground Operation." The first deals mainly with late-WWII vehicles, but includes references up to 1970. The later deals with WWI, WWII, and Cold War wheeled and tracked vehicles up till about the mid-1970s.

sounds interesting - tried to get hold of these here on the old continent - no avail. do you have any public sources? or sources available on the internet?

[Stndrtnfhr]

I have become a firm believer that the bogging/imob percentages are set way too high. Playing the Letzte Hofnung, 75% of my vehicle losses were to bogging/imob, not enemy action.

I am playing "A Strange Awakening" and I just had a PSW 223 bog/imob after moving 5m on the road. The conditions are warm and dry and his damage screen shows engine and wheels are both a green square, no damage. How do you figure it is now immobilized??

[JonS]

sounds interesting - tried to get hold of these here on the old continent - no avail. do you have any public sources? or sources available on the internet?

Sorry, no. If you google it you'll find loads of references to it, but no actual content. Although - I think one of the links is to the proceedings of the conference at which it was presented, which should hold the paper in full.

Here;

http://www.istvs.org/publications/proceedings/international-conferences/4th-international-conference-stockholm-sweden-1972.html

(175euros :eek: )

But, my google-fu on this is weak. Someone with a bit more nous might be able to dig up a copy.

[A Canadian Cat]

I completed the dry tests with tanks - two speeds slow and fast

Here are the updated results (some of it repeats the first post data):

Percentage of operational vehicles when traveling 7km over the test course

[B]Vehicle	Conditions / Speed

	Dry

	Fast	Slow[/B]

Sherman	22.67%	30.67%

Panther	44.00%	37.33%

PzIV	36.00%	29.33%

Of the vehicles that became Immobilized; here is the break down between terrain types the immobilization occurred.

Sherman

[B]	Fast	Slow[/B]

Mud	34.67%	26.67%

Sand	 2.67%	 0%

Rocky	 2.67%	 0%

GrassXT	 2.67%	 0%

Ford	34.67%	42.67%

Panther

[B]	Fast	Slow[/B]

Mud	28.00%	26.67%

Sand	 1.33%	 0%

Rocky	 0.00%	 0%

GrassXT	 0.00%	 2.67%

Ford	26.67%	33.33%

PzIV

[B]	Fast	Slow[/B]

Mud	38.67%	28.00%

Sand	 0.00%	 0%

Rocky	 0.00%	 0%

GrassXT	 0.00%	 4.00%

Ford	25.33%	38.67%

[A Canadian Cat]

Here are the updated results (some of it repeats the first post data):

Percentage of operational vehicles when traveling 7km over the test course

[B]Vehicle	Conditions / Speed

	Dry

	Fast	Slow[/B]

Sherman	22.67%	30.67%

Panther	44.00%	37.33%

PzIV	36.00%	29.33%

Larger numbers are better. Looks like Shermans benefited from going slow but other tanks performed worse.

Does this level of immobilization seem reasonable? As an example in a large and long battle in dry conditions does it seem reasonable to have such a large number of tanks become immobilized? If tanks do not cross fords and never drive in the mud they would fair much better. Can I tell where mud is vs dirt in the game?

Testing some wheeled vehicles is next.

Then wet conditions so see what happens then.

Then I'll add roads onto the test course and just drive on the roads to see what that does.

This is going to take a while:-)

[Erwin]

Did you try "Wet" conditions?

And re your very interesting results, the high rate of immobilization is frustrating for an entertainment product - EVEN if it were reflected by RL. Yes, if you want a simulation to test out RL tactics etc and logistics one needs accuracy. I could understand that for modern war depicted in CMSF (not that they immobilized much at all of course). But, for a WW2 game that one turns to for leisure/enjoyment...

[sburke]

Can you show the numbers used for those percentages? - ie did you test 5x, 10x etc.

[TheVulture]

I'll just throw in my observation from Die Letzte Hoffnung that in one scenario I had 5 incicents of bogging (only one immobilisation) and that every single one was when a vehicle was crossing on to / off from a road. That's not a big enough sample to draw any conclusions from, but does suggest the possibility that being half-on half-off a road is a big bogging hazard. One day I'll get around to doing some testing on that, but just thought I'd mention it in case anyone else is feeling highly motivated to run some tests before I get around to it.

[A Canadian Cat]

5 incicents of bogging (only one immobilisation) and that every single one was when a vehicle was crossing on to / off from a road.

I have had that happen as well. I'll have to think how to test for that.

Can you show the numbers used for those percentages? - ie did you test 5x, 10x etc.

Sure, each number is based on 75 vehicles running over a 1.2Km course 6 times. I created a course map and then added 15 vehicles and ran the test 5 times for each. The saved games and map are linked in the original message.

Did you try "Wet" conditions?

Not yet. I want to but each of these tests takes time away from play:-). I'll get to it at some point. I am concerned that the amount of immobilization is to high. So, I am trying to get some data to start the discussion.

And re your very interesting results, the high rate of immobilization is frustrating for an entertainment product - EVEN if it were reflected by RL. Yes, if you want a simulation to test out RL tactics etc and logistics one needs accuracy. I could understand that for modern war depicted in CMSF (not that they immobilized much at all of course). But, for a WW2 game that one turns to for leisure/enjoyment...

I see what you are saying and why, but I do not agree. I want an accurate experience. If bogging and immobilization was a serious problem in WWII I want to experience that problem too.

However, and this is why I brought it up and devised some kind of test, I am concerned that immobilization is happening too often.

[A Canadian Cat]

I realized I did not link to the saved games for slow so here they are:

http://lesliesoftware.com/forforumposts/Bogging%20Test%20Dry%20Slow%20Shermans%20001.bts

http://lesliesoftware.com/forforumposts/Bogging%20Test%20Dry%20Slow%20Panthers%20001.bts

http://lesliesoftware.com/forforumposts/Bogging%20Test%20Dry%20Slow%20PzIVs.bts

and as a bonus here is the results spread sheet (created with Open Office Calc, first tab shows summary, second tab shows results for each trial etc.):

http://lesliesoftware.com/forforumposts/Bogging%20Results.ods

[DavidFields]

And re your very interesting results, the high rate of immobilization is frustrating for an entertainment product - EVEN if it were reflected by RL. Yes, if you want a simulation to test out RL tactics etc and logistics one needs accuracy. I could understand that for modern war depicted in CMSF (not that they immobilized much at all of course). But, for a WW2 game that one turns to for leisure/enjoyment...

I can see both sides of this issue, but I understand where you are coming from, Erwin. A player likes to feel his decisions affect something. That is why a scenario where you just sat under a massive artillery barrage the entire time, where nothing you did could help you, would not be fun.

In CMBN, particularly since many of the scenarios are so much longer than CM1 scenarios, high AFV bogging, even when you are trying to keep your AFVs on dry ground, blunts the fun. Yes, things happen in war. But if the result is to make events essentially random, then why even play?

If the bog rate is realistic, then so be it. It is yet another "CMBN has elements different than every other simulation in its genre". But if realism is not fun, that is a problem--most simulators would provide some assumptions to blunt that--even if one needed to explicitly note that in the manuals.

[Bruceov2]

I wish Battlefront would say something about the bog rate i.e does going slow help

[Praetori]

I can see both sides of this issue, but I understand where you are coming from, Erwin. A player likes to feel his decisions affect something. That is why a scenario where you just sat under a massive artillery barrage the entire time, where nothing you did could help you, would not be fun.

In CMBN, particularly since many of the scenarios are so much longer than CM1 scenarios, high AFV bogging, even when you are trying to keep your AFVs on dry ground, blunts the fun. Yes, things happen in war. But if the result is to make events essentially random, then why even play?

If the bog rate is realistic, then so be it. It is yet another "CMBN has elements different than every other simulation in its genre". But if realism is not fun, that is a problem--most simulators would provide some assumptions to blunt that--even if one needed to explicitly note that in the manuals.

Well bogging is one thing. Immobilization a different matter.

Having been mechanized myself I'm not surprised at all by the figures. Heavy vehicles going off-road results in bogging all the time. That the bogging results in immobilization is pretty rare with modern AFVs and MBTs though it happens.

Going SLOW I feel could also be an abstraction. Momentum is good BUT it prevents the driver and commander from navigating the terrain properly. Tree-stubs, rocks and other obstacles are best avoided no matter what vehicle you're in. Every obstacle no matter how easy to just roll over can bog you. A decently sized stone can de-rail the tracks of a MBT if it gets between the track-guards.

What it all comes down to is that IF the figures for ww2 vehicles are correct (and I have no reason to suspect they're not) it's still a game. Had we been given the opportunity to tow/recover bogged/immobilized vehicles with other tanks or say the SdKfz.9 for the Germans that would be a different matter. Throw in some ability to re-arm the tanks as well and at least I'd be a happy bogger.

[Sgt Schultz]

I would love to be able to push vehicles like we used to.

Hard coded prime movers with a TOW command would be even better.

[Paul AU]

I have become a firm believer that the bogging/imob percentages are set way too high. Playing the Letzte Hofnung, 75% of my vehicle losses were to bogging/imob, not enemy action.

I am playing "A Strange Awakening" and I just had a PSW 223 bog/imob after moving 5m on the road. The conditions are warm and dry and his damage screen shows engine and wheels are both a green square, no damage. ?

Many immobilisations are especially annoying because they’re completely UNavoidable, and not due to your mistake or enemy action. I expect trouble if I drive through a ford, but not on a road or dry firm land.

A solution would be for BCF to add an “immobilisation slider” in Preferences, so the player could influence the probability of bogging or immobilisation. (Two sliders, then).

I’ve suggested this before, but BFC’s reply (paraphrased) was “Nah, we prefer realism. Part of that realism is getting unlucky sometimes.”

My main complaint was that small games are frequently won or lost on who is immobilised first. You could effectively lose 100% of your armour because you dared to drive down the road. 5 metres in the above example. It’s a game-breaker.

And while losing a game (and wasting all the set-up time) may be realistic (and it’s obvious that many here think that BFC’s immobilisation regime is not realistic), it’s not fun. It’s no fun to have a game screwed by a risk you CANNOT avoid taking – eg, moving down a road.

I can’t see what harm giving players some control over immobilisation probability would do. I don’t think it’s a big job to implement.

I suppose I have unrealistic, expectations.

[akd]

As an example in a large and long battle in dry conditions does it seem reasonable to have such a large number of tanks become immobilized?

No reasonable conclusions to that question can be drawn from your tests since you included mud and water. There is no dry mud or dry water in CMBN, so this is not really a test of the effect of dry conditions.

The speed results are interesting, although I'm not sure definite conclusions can be drawn from this particular setup.

[A Canadian Cat]

No reasonable conclusions to that question can be drawn from your tests since you included mud and water. There is no dry mud or dry water in CMBN.

Yes, those are the high risk areas - as they should be. It is interesting that the Sherman bogged in other places in dry conditions more than the other tanks.

Sounds like you are suggesting I should consider retooling the course to remove the high risk terrain and see what happens then.

That might be reasonable. The other thing I am seeing is people reporting bogging on the edge of roads. So, perhaps my test course should be tweaked to remove the wet stuff add roads and drive on and off roads and see what happens.

I'll think about that - while I am pressing the big red button for the wheeled vehicles' tests:-)

[akd]

My main complaint was that small games are frequently won or lost on who is immobilised first. You could effectively lose 100% of your armour because you dared to drive down the road. 5 metres in the above example. It’s a game-breaker.

If it is happening in a particular circumstance where it should not be, it is probably a bug and will be addressed if reproducible. But that has nothing to do with your overall point.

(and it’s obvious that many here think that BFC’s immobilisation regime is not realistic), it’s not fun. It’s no fun to have a game screwed by a risk you CANNOT avoid taking – eg, moving down a road.

I think it is fun.

[akd]

Yes, those are the high risk areas - as they should be. It is interesting that the Sherman bogged in other places in dry conditions more than the other tanks.

Well, Sherman has higher ground pressure than the other tanks.

Sounds like you are suggesting I should consider retooling the course to remove the high risk terrain and see what happens then.

That might be reasonable.

Depends on what you are trying to accomplish.

The other thing I am seeing is people reporting bogging on the edge of roads. So, perhaps my test course should be tweaked to remove the wet stuff add roads and drive on and off roads and see what happens.

I'll think about that - while I am pressing the big red button for the wheeled vehicles' tests:-)

If you can carefully control the factors in the test and isolate down to a reproducible set of factors, then go for it. I haven't seen enough to conclude there is a problem worth testing.

p.s. I just glanced at your test course. Each tank was run through 1.4 km of mud and river. Having on average a third of your vehicles not requiring recovery is really not that bad.

[Erwin]

There is still the basic point of why people play wargames in general and the CM series specifically. Clearly there are differing motivations amongst us.

However, I do not want to play CM: LOGISTICS COMMANDER, or CM: MAINTENANCE CREW cos it's not as much fun running around imagining myself as a terrific platoon/Co/Bn/KG commander and blowing things up.

However, I know it's all BS and not a lot to do with the RL job of those positions... and being good at CM does not mean one would be worth spit in the RL job.

A game needs to focus on the fun aspects - and that doesn't include having 20%-30% of your tanks immobilized in every scenario of a campaign.

[akd]

doesn't include having 20%-30% of your tanks immobilized in every scenario of a campaign.

Making up or exaggerating numbers to support your "point" (which is nothing but a subjective standard of "fun") is not a good way to go about having a discussion around these parts.

[winkelried]

Started to do some testing: map 4x1km 55 M4A3 75(W) mid Sherman tanks (since they seem to perform so badly):

drive per test 16 km with 55 tanks = cumulated 880 km

Ground: Very dry grass (as reference test)

Fast approx 34 km/h 8 bogged 2 immobile

Quick approx 30 km/h 7 bogged 2 immobile

Move approx 16 km/h 1 bogged 1 immobile

bogging between 10 and 70 seconds.

will now continue with wetter ground.

[A Canadian Cat]

<snip>

If you can carefully control the factors in the test and isolate down to a reproducible set of factors, then go for it. I haven't seen enough to conclude there is a problem worth testing.

p.s. I just glanced at your test course. Each tank was run through 1.4 km of mud and river. Having on average a third of your vehicles not requiring recovery is really not that bad.

I started this testing because based on my own experience that Shermans seemed to become immobilized in safe areas often. I have played several scenarios where I have lost 1/3 or a 1/2 of my tanks well away from enemy action and it has effected the outcome of the game.

Then in Huzzar my main attack force was severely hampered and cut in half by trouble in a ford.

So, far my testing has convinced me that Fords and Mud are not a safe place to go. I did not expect them to be that bad but it seems they are. It is still not clear if that is realistic or not. I fear it is not but I have no evidence. All I can offer is some test on how the game operates.

Again I am interested in how the vehicles behave in the game. If showing that combined with some external evidence that I don't have indicates there is a problem then it will get fixed. If there is no problem then we all know what to be careful of.

My plan now is to get ride of the high risk areas on the course and focus on normal terrain and roads. My own experience plus some other anecdotal evidence suggests that looking at roads would be worth while. My plan is to check how roads compare to off road and how transitioning from road to off road factors in.

My text test course will include space for 10 tanks to run cross country, 10 to run on dirt roads, 10 to run on gravel roads, 10 to drive on a mix of dirt road and off road, 10 to run on a mix of gravel road and off road.

I am interested in seeing if there are issues with the transition between road and off road and if being on a road makes a difference or not (the roads will go over the same terrain as the cross country tanks).