Bocage and cover/concealment: Part 2

[SteveP]

In another thread, I noted that concealment for defenders in a bocage was good but not excellent -- some significant portion would give away their positions before anyone even fired a shot. Cover was also good, but not great, and defenders there were particularly vulnerable to small mortar fire (which was generally too impractical or dangerous for use IRL) that could be dropped on them as soon as they revealed themselves.

There is a way to solve the problem of getting very strong cover/concealment in a bocage defense line, but it can only be done in scenarios and has some quirky impact on graphics.

While it is not possible to place a trench under bocage, it is possible to place bocage on top of a trench. The same with foxholes.

With a line of trenches underneath the bocage, the defenders have excellent, perhaps even complete concealment. Cover from mortar fire is also very good, and certainly good enough if they aren't getting spotted in the first place.

With a spread of foxholes under the bocage, the defender gets better concealment -- almost as good as with the trenches. Cover may be better as well, but not much better for mortar fire. Still, if they aren't getting spotted, they have a much better chance of doing some damage before getting mortared.

Unfortunately, there are some artifacts in the graphics that people may find objectionable -- particularly the foxhole option. Also the graphics tend to give away the location of trenches and foxholes, so you would need more of them than required by the number of units in order not to give away positions.

In any event, I think either of these options would make it possible to create a bocage defense that was truly scary.

I plan to experiment a bit further with this, to see if there are other issues, but I thought others might want to experiment as well, so that's the reason for this post.

[Michael Emrys]

While it is not possible to place a trench under bocage, it is possible to place bocage on top of a trench. The same with foxholes.

Interesting.

Michael

[SteveP]

Nope, didn't work after all. I tried to tailor a bocage scenario to use this idea and to model the RL effectiveness of a bocage defense. I could not do it. It may not be possible. Concealment has to be much stronger, and mortar accuracy weaker. The trenches don't really help. I think this is because they aren't very good for concealment or cover themselves, and bocage plus trenches isn't additive. Even snipers give themselves away, without firing a shot, which is pretty unbelievable.

Oh, well ...

[RockinHarry]

Wondered if this sort of placement allowed reoccupation of FHs/trenches, once they were abandoned.

The "best" bocage defense I applied so far, was having an outpost line (2-3 men teams, snipers) just at the bocage, with main forces either 1-2 action spots or whole bocage field behind in FHs or trenches. Staying away from trees helped vs. artillery. Registered mortar fire does the main work on attacking infantry.

Creating "strongpoints" around hamlets in connected trench lines, with just having OP in upper stories (if present) also makes a tougher opposition.

HMGs are best placed with "long" fields of fire from flanking positions, which in bocage terrain means, along roads that need to be crossed by enemy infantry sooner or later. Field of fire s/b 300-400m minimum. Otherwise, small LMG teams are way better suited at close ranges. HMG teams also must be covered frontally by terrain and friendlies.

All that worked quite well in Busting the Bocage vs. US AIP, but a human US opponent would be similarly challenged I guess.

Edit: Off course this particular setup "cheats" on the US AI plans for this scenario, but generally serves quite well for the demonstration purpose.

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[SteveP]

“The military features of the Bocage are obvious. The hedgerows divide the country into tiny compartments. The hedgerows in each field provide excellent cover and concealment to the defender and present a formidable obstacle to the attacker.

Unable to use normal techniques of fire and maneuver, American commanders were also powerless to influence the battle with increased firepower. Heavy vegetation and the close proximity of the German defenders made it impossible to bring forward and set up heavy machine guns. Company commanders used their organic 60-mm mortars in an attempt to knock out German machine-gun positions. However, the hedgerows and the close combat conditions made the observation and adjustment of mortar and artillery fire almost impossible. American and German units often fought one another at ranges of less than 300 yards. Short distances made calling for artillery fire risky, since unadjusted rounds could easily land on friendly troops. Many engagements were fought at such close range that even if friendly rounds landed on German positions, the effects of shrapnel and concussion would endanger American lives. Unable to observe the enemy and to call fire on him from a safe distance, infantrymen were deprived of field artillery and mortar support.

American commanders quickly discovered that four or five German defensive positions could pin down an entire infantry battalion and hold up an attack for long periods.

General Collins of VII Corps was equally surprised by the nature of the hedgerow terrain and told General Bradley on 9 June that the Bocage was as bad as anything he had encountered on Guadalcanal.”

What I was trying to do is create a bocage defense for the AI that would impose this sort of problem for the player, as described in these quotes – for example, the ability to hold a single bocage field with a couple of HMGs, a couple of LMGs and a sniper or two, with perhaps a rifle squad. In CMBN, a vanilla US rifle company can destroy this defense in 30 minutes or less. I have not been able to figure out a way around that. Certainly not to create something comparable to Guadalcanal.

Of course, if that problem could be solved, then it would be possible to build a somewhat larger scenario which demonstrated the strength of interlocking defenses across 2-3 lines of bocage fields.

[RockinHarry]

We´ll see, if the 1.01 patch will improve on cover/concealment matters enough, to get sorts of a historical german bocage defense setup working at last. At least some of the artillery vulnerability vs. infantry in FHs/trenches is beeing dealt with (bug).

http://www.battlefront.com/community/showthread.php?t=97855&page=3

Wished there would be a modifier (abstracted), that gives defending units, if they do not leave their initial positions, sorts of a concealment bonus, if the battle is of the "assault" type and defending units can be assumed to be well prepared/concealed.

Or like in CMX1, that HQs/leader traits give a camouflage bonus to subordinates.

Do "Ambush 75" and "Hide" AI zones help the defender in any way?

[SteveP]

Do "Ambush 75" and "Hide" AI zones help the defender in any way?

Not really. The defensive units are giving away their positions without even firing a shot -- including snipers, which is really wrong. So an Ambush order doesn't do much.

Hide would help, but then you have to give a script order for the AI to unhide at some point (which has to be at a certain time in the game) or else they just stay there until the US infantry gets into grenade range. I've thought about trying that out (with say a 3 minute Hide), and just haven't yet. Where I think that might work really well is in a situation where the US player doesn't know in advance what bocage line on the map is going to be defended. In that case, he might well be caught in the open when the AI unHides (if you get the timing right in the script). A bit of a kludge, but a combination of techniques like that might produce something that looks like a real bocage assault battle.

Also, one of the common problems with the bocage scenarios I've seen is too few, or no, TRPs. IRL, the bocage fields were full of registered targets. An overwhelming % of US infantry casualties in Normandy were from mortars, most of them in these fields. I think the AI can figure out how and when to do this OK, if the US infantry can be enticed into the fields before their own mortars (and MG fire) do major damage to the defenders. What is really unrealistic are the firefights that go on across the field, from one bocage to the other. IRL that couldn't have happened and/or would have been a waste of ammo.

I agree that if units in the bocage got anything like the kind of concealment they did IRL, the resulting battles probably would look much like they did IRL.

[Childress]

Have you tried inserting a layer of Light Forest tiles under the bocage?

[RockinHarry]

Have you tried inserting a layer of Light Forest tiles under the bocage?

Interesting! I was just trying the same in the editor, placing "heavy forest", "Tall grass" and "brush" beneath the bocage/hedge variants, although I could do no tests in the demoes editor.

"heavy forest" should also make the "tall bocage" layer unbreachable, or at least "impassable" to vehicles if it can be breached.

Another point of interest would be the predominant type of terrain in the fields between the bocage. I wouldn´t necessarily assume the fields would be all low grass, dirt or plowed field, in order to have full view across the whole field up to the opposing bocage line. If terrain obstructions would be present (fields in June/July 1944), it was more of a common defenders practice to "cut" fields of fire, instead of removing all of them. A map maker can do the same, by proper placement of ground types (variations of dirt, low grass, brush and crops).

[RockinHarry]

Not really. The defensive units are giving away their positions without even firing a shot -- including snipers, which is really wrong. So an Ambush order doesn't do much.

I can confirm from my playing of Busting the Bocage, although I have no idea of the AI plans for this scenario. Would like to know if AI plans have any effects on units, if particular scenario side is human played.

Also, one of the common problems with the bocage scenarios I've seen is too few, or no, TRPs. IRL, the bocage fields were full of registered targets. An overwhelming % of US infantry casualties in Normandy were from mortars, most of them in these fields. I think the AI can figure out how and when to do this OK, if the US infantry can be enticed into the fields before their own mortars (and MG fire) do major damage to the defenders. What is really unrealistic are the firefights that go on across the field, from one bocage to the other. IRL that couldn't have happened and/or would have been a waste of ammo.

How does the AIP make (good) use of TRPs? Do "hidden" units unhide earlier to engage enemy units, if they enter TRP zones?

I could think of trying to beef up bocage with additional "concealment" layers (light/heavy forest, ect.), restrict lines of fire within the fields between bocage lines, proper placement of half squads / LMG teams in accordance with the map edited fire lanes and use of a reasonable number of TRPs for the defender. If still none of the AI plans can get to work with this sort of "bocage defense", then I think BFC needs to think about some tweaking.

[SteveP]

Have you tried inserting a layer of Light Forest tiles under the bocage?

Yes. AFAICT, there is no "additive" factor you can use. I assume the game engine calculates based on whatever is the strongest feature in the Action Spot.

It would be possible to put a visual obstruction on the US side of the bocage field (low bocage, say). That would force the US player to move forces into a more vulnerable position in order to spot the defenders. I was trying to avoid doing anything that looked terribly contrived (I could justify the trenches, because the Germans did in fact cut slit trenches into the bocage).

Still, I can't say that I've tried every option by any means, and even though I am doubtful, I may try some other ideas before giving up completely.

[RockinHarry]

Found this to be quite useful to determine predominant types of terrain in normandy (campagne, bocage):

http://translate.google.com/translate?js=n&prev=_t&hl=de&ie=ISO-8859-1&layout=2&eotf=1&sl=de&tl=en&u=http%3A%2F%2Fwww.normandie-netz.de%2F165%2FLandschaft-und-Umwelt.html

So it mostly depends upon a specific area (of normandy), whether fields are predominantly meadows & apple trees, or crops.

[RockinHarry]

So something get to work is this:

By rknharry at 2011-06-02

100m bocage sectors are defended by roughly 1-2 infantry squads, with 2-3 LMG (I doubt, there were many true tripod HMGs incorporated, if LOF is just 100-200m.)

Infantry and LMG teams occupied 2-3 men rifle pits with adjoining small dugouts at the hedgerows.

Germans mostly occupied the fields containing trees & orchards for overhead concealment.

The "enemy" fields are mostly of the meadow type, or have scattered trees. I´d also assume germans cut down many of the apple trees to improve field of fire and for use as foxhole cover.

Lateral movements are provided by small gaps in adjoining hedgerows and well concealed by the many trees and frontal hedgerows, thus there was no true necessity to build trenches between positions.

One can also assume germans to have each field "registered" for artillery, as well as suspected enemy assembly zones.

Single buildings/hamlets were mostly spared, since they attract enemy artillery.

I just can do guessings about use of obstacles and minefieds, but I´d assume that "roadblocks" at least would be "booby trapped" and weakly held sections would be strengthened with AP mines.

AT guns would cover usable roads and crossroads.

[SteveP]

100m bocage sectors are defended by roughly 1-2 infantry squads, with 2-3 LMG (I doubt, there were many true tripod HMGs incorporated, if LOF is just 100-200m.)

Something I have not come across is anything that describes exactly what the Germans did, except as the US surmised from several days of fighting in the bocage for the first time. Certainly, the US believed that they were always facing at least one, if not two, HMGs in each field. It's possible that the Germans figured out the likely direction of attack, and moved reserve units including HMG teams into those areas. The US view was that the LMGs were there primarily to provide grazing fire to keep the US troops in the middle of the bocage field, while the HMGs kept them pinned down. The mortars did the real damage.

One can also assume germans to have each field "registered" for artillery, as well as suspected enemy assembly zones.

It doesn't appear that the Germans used artillery against rear or assembly areas as effectively as the Allies. For one thing, the US had spotter planes that could adjust fire, while the Germans were fairly blind. But every bocage field was registered (as one would expect in any planned defense).

I just can do guessings about use of obstacles and minefieds, but I´d assume that "roadblocks" at least would be "booby trapped" and weakly held sections would be strengthened with AP mines. AT guns would cover usable roads and crossroads.

AP mines definitely. All AT weapons and devices were focused on the road network, including the narrow roads running through the bocage country itself, until the US figured out how to get tanks working effectively in the bocage itself.

What I was hoping to do is create a small (company or two company) map that could be used for 3 different scenarios: one set in mid-June, the 2nd in late June, the 3rd in mid-July, providing an opportunity to explore how the US adapted to the bocage, and what the Germans did to counter those adaptations. But making that work in a realistic way means that the bocage has to be a very nasty (and bloody) problem for the US infantry in that first scenario. Until I figure out how to do that, the whole scheme looks like a field training exercise (with live ammo ).

[RockinHarry]

The original german positions map from the St-Lo book, is even more enlightening. Good stuff for in depth analysis:

http://www.history.army.mil/books/wwii/100-13/mp16.jpg

[RockinHarry]

Diagonal placement of hedgerows makes the sub mesh geometry appear rougher and adding 1m to placement spot, pronounces the effect. Would be interested, if this altered geometry has any effect on cover/concealment with infantry positioned there.

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[SteveP]

I finally got around to running real tests on a map I created. The focus of these tests was entirely about concealment. I had both sides set with short cover arcs, so there was no shooting. And I ran the tests for 3 minutes each time, to see how many enemy units popped into view before any shots were fired.

The good news is that there is a solution for concealment that is within acceptable limits for a realistic bocage battle. I had been running tests using an existing scenario (by an excellent mapmaker). It turns out that the distances, though quite realistic for bocage country, were too short for CMBN.

Concealment effectiveness varies somewhat depending on the experience level of the spotter(s) and perhaps also of the defenders, plus number of spotters, number of binocs, etc. So getting precise numbers for all the variables is impractical. However, what I have found is that concealment starts to become realistic at a distance of 160m and there is no practical need for a distance greater than 200m. We can certainly make realistic looking bocage maps within those parameters.

The big disappointment is snipers. They reveal their positions as soon as they start shooting at anything. I am sure this is a general problem, not just bocage, and seems to be about the same as it was in CM1. Back then, BFC said these guys weren't really snipers, just sharpshooters who would otherwise be part of rifle squads. So I have to assume that is what they would say here.

Unfortunately, snipers were a valuable part of a bocage defense, as they could pick off small scouting teams before they could gather any useful info -- plus demoralize and pin green squads. OTOH, given the distances we are talking about here, snipers may be able to survive most the fire that gets sent their way, which would force the US to use mortars on them. It's food for thought at this point, nothing more.

I will probably be doing some similar testing on cover shortly.