"Smoke is too benign" ... discuss

[GreenAsJade]

In a galaxy far far away , Prof Oz commented:

My father commanded a platoon of 81-mm mortars in Normandy (H Co, 2/117th, 30th Infantry Dvision). I asked him about the use of smoke. He confirmed that they used white phosphorus in great abundance, more for its ability to cause penetrating burns than for screening advances or even setting brush on fire. Tree bursts were particularly favored for spraying an enemy position with white-hot particles as well as splinters.

So, our ability in CM to move troops through smoke screens and even continue to put additional smoke rounds into an area containing friendly troops is an oversight of the designers.

... comments?

[Wicky]

This was Steve's statement in 2000 on WP in CM:

http://www.battlefront.com/discuss/ultimatebb.php?ubb=get_topic;f=13;t=003021#000022

Unless we can figure out WHY then WP stays out of the game because to introduce it would open the door to unrealisticly high use of WP, therefore reducing the historical accuracy of the game. So the irony here is that NOT including WP might make CM more realistic than if we included it.

Steve

[simovitch]

ala ASL..

Make the use of WP scenario specific by allowing the designer the option of checking a box in the "parameters" screen. Same for POZIT.

[YankeeDog]

FWIW, I agree that leaving WP out of CM was a mistake. From what I've read, it's use actually was pretty damn common, epecially at the lower caliber levels.

But this issue has been hashed and re-hashed ad nauseam, and the game designers have made their opinions clear. I think the best to hope for at this point is that CMX2's artillery system will allow a more in-depth modeling of artillery in general, inclding types of ammunition available. BFC has already made noise that there are going to be some pretty fundamental changes to the way artillery works in CMX2.

Cheers,

YD

[Wartgamer]

This is Charles comment..1999

At the moment we're leaning away from modeling white phosphorous (WP) separate from "regular" smoke. The reason is mostly that we want to keep the user interface from getting too complicated.

I don't think that US artillery fired WP in the indirect fire mode (what in CM would be "off map" artillery). But someone please correct me on that if I'm wrong.

My understanding is that WP was fired most often by tanks in direct-fire mode. I'd rather not have separate orders and separate ammo tracking for smoke and WP rounds, so we might give slightly different behaviors to smoke rounds fired from American tanks (like a chance to cause fires).

Charles

I'm not sure I'd want to bother including WP as an off-map mortar (or artillery) round because I think such use was infrequent (though I could be wrong about that so let me know if you come across differing evidence). The case you cite was 4.2" mortars, which were intended as "chemical mortars" and therefore more likely to use WP than anyone else, but 4.2" mortars were pretty rare. Also, the attack you described seems quite similar in effect to a conventional high-explosive attack in terms of the damage caused. In fact it's entirely likely that the 4.2" mortars used WP because, being "chemical mortars", they had no little or no high-explosive on hand.

I'm also familiar with a few cases of Shermans firing WP at heavy tanks and tricking them into bailing out. But this isn't the kind of thing that can reasonably simulated in a game like CM, because it was a very rare occurrence. It's not as if Panther crews were bailing out of tanks all over the Western front due to WP hits, so I don't want to encourage "one in a million" tactics which are unrepresentative of typical combat.

However, it appears the use of WP from direct-fire ordnance, especially tanks, against enemy infantry was fairly common. So I'm struggling with a way to include WP without overburdening the ammo supply/display/user-interface in the game.

I'm wondering what everyone thinks. Would it be reasonable to implement Combat Mission so that American tanks (and maybe tank destroyers) always use WP instead of conventional smoke? It would be easy to include WP "for real" if I don't have to worry about units carrying both WP and conventional smoke at the same time. If it's one or the other, I can put it into the game. But is this acceptably realistic?

Charles

[Wartgamer]

http://www.battlefront.com/discuss/Forum1/HTML/000420.html

This thread discusses the reasons.

[MikeyD]

I can well imagine the howls of pain if WP was used in the game.

"My troops refused to walk through my own smoke screen!"

"My men keep getting supressed/panicked by smoke!"

"After the artillery smoke bombardment half the map became 'off limits' for the rest of the game!"

"My covering smokescreen set the whole town on fire!"

"My expensive über-Tiger had its crew bail after being hit by a lousy smoke shell!"

[Lars]

I want phosgene.

[Wartgamer]

WP does not burn for as long as a scenario. So you are imagining too much. Friendlies can enter the smoke screen within minutes.

Non-WP smoke will make a tank crew bail out. It is sucked into the crew compartment (by fans) and makes operating the vehicle impossible. A field expedient is to take two smoke grenades and tie them together. This is then thrown over the vehicle.

WP burning particles can be sucked into the engine compartment by the powerful fans and destroy wires/hoses/radiators/fuel/etc.

[Guest Mike]

I'd just like to see 2" mortars able to produce the hundred yard long screens they aparently could do in real life with their 10 rounds!!

[flamingknives]

Ditto

[Pzman]

That only works if you get all the 2" mortars in company working together silly.

[Wartgamer]

Did 2 inch mortars have some uber smoke fillings? They probably had the same fillings as many non-WP smoke shells. Except less.

[Guest Mike]

Nope - I read somewhere on one of these boards an extract from a manual claiming that the standard 2" mortar load could maintain a 450m (or yard??) smoke screen for 5 minutes - it was a training manual or an operational manual?

I presume that other smoke in CM* is similarly nerfed.

[Michael Emrys]

Originally posted by Mike:

I presume that other smoke in CM* is similarly nerfed.

I've always made that assumption. Maybe BFC just factored in dispersion due to wind and rain without telling us, but I have always thought that visibility on the CM battlefield was better (at least in daylight) than in the real world. There have been threads on this before.

Michael

[GreenAsJade]

So, back off for a moment to the basics .... you're saying that there's "regular" smoke and then there's "WP" smoke?

What is this 'regular' smoke? Doesn't it too make you cough and choke?

This particular thread started from the innocent question "how come I can waltz through my smoke screen?". The answer was "actually, that's a mistake, you shouldn't be able to 'cause your smoke screen was made with WP, which is nasty". Now I'm hearing "you smoke screen is just regular smoke, not WP". So - what is "regular smoke" and how come it does't choke me when I rain it on myself?

GaJ

[Grach]

2" mortars were initially issued with a pyrotechnic candle style smoke round. By 1942 a WP smoke/incendiary round had been added to the inventory as well and was in common use.

Most other British smoke was base eject 'cold chemical' (TCE/TiTC) types.

Interestingly enough there is an important caveat to this (as far as CMAK is concerned.)

The smoke rounds for the 3.7" close-support mortars on the A9, A10 and A13 Mk II CS tanks were WP types being designs from the late '20's.

IIRC there was also a (not very efficient) HE shell issued for this weapon too. According to Jentz's book "Tank Combat in North Africa" the ammo stowage of the A9 and A10 CS tanks was 36 rounds of (WP) smoke and 4 of HE. The 15-lb. HE/T, travelled at 620 fps. The WP smoke round was 15-lb, 5-oz and attained the same velocity.

If modelled it'd make these vehicles handle a little differently.

(Only other British use of WP smoke was in mortars (as noted above) and mountain howitzers. Plus whatever US lend-lease gear had it.)

AFAIK the later 3" and 95mm close support howitzers adopted BE smoke.

Cheers!

[GreenAsJade]

So - to summarise - after 1942 at least, there's a darn good chance that the smoke you're using is WP, so BTS's original argument "we don't know whether WP was deliberately used offensively" is moot. The fact is the smoke is likely coming from something nasty, so the way we wander our troops through it (and happily fire out of trenches and buildings covered in it) is undermodelled.

Right?

GaJ

[Grach]

What I meant was, from 1942 the Commonwealth 2" mortar had a WP round available for it in addition to the usual screening and signalling smoke shells.

The British seemed rather reluctant to use WP/RP as, for the purposes of screening, BE 'cold chemical' smokes (the name is a little misleading, most of these mixtures did burn) produced a much more effective cloud.

Incendiary smoke tends to pillar and rise into the air due to the heat of combustion. 'Cold chemical' smoke hugs the ground and spreads there, lingering longer.

Indeed, most nations seemed to be of the opinion that a good HE/Frag round was far better at upsetting people than the undeniably nasty effects of WP/RP.

I'd almost be tempted to say the US predeliction for phosphorous may be due to the virtues of their huge manufacturing capacity. When you can churn out that much gear you can afford a bit of variety!

Nevertheless I think it would be nice if the CMx engine were able to replicate the effects of WP/RP and BE smoke. After all some BE smoke mixtures were moderately toxic and many had at least some value as an irritant/lachrimator. Not the sort of thing one wanders around in without effect. WP/RP smoke even less so.

Cheers

[flamingknives]

Originally posted by Mike:

Nope - I read somewhere on one of these boards an extract from a manual claiming that the standard 2" mortar load could maintain a 450m (or yard??) smoke screen for 5 minutes - it was a training manual or an operational manual?

I presume that other smoke in CM* is similarly nerfed.

Probably myself or John Salt quoting from "Salt's Snippets", a summary of innumerable War Office documents, compiled by John Salt and posted at http://salts.britwar.co.uk/

The section on 2" mortars is in the weapon effectiveness one.

</font><blockquote>code:</font><hr /><pre style="font-size:x-small; font-family: monospace;">WO 32/10577 Tactical employment of smoke

This table gives "No. to produce 500 yards screen in 10 m.p.h. wind on a cloudy day. On a bright sunny

day or with low or high winds, expenditure of ammunition may have to be appreciably increased."

25 pdr BES 3 candles, burn for 1½ mins 2 rds/min

4.2" mortar 25 lbs WP, 3,000 yds 6 bombs/min (theoretical)

3" mortar WP 1,600 yds 10 bombs/min

2" mortar 2 mins emission 500 yds 9 bombs/min

3" AFV howitzer 1500 yds 3 rds/min

2" bomb thrower 2lb smoke mixture 150 yds being replaced by WP

4" smoke discharger 3½ lbs smoke mixture 90 yds lighter AFVs only

The "pillaring" tendency of WP rounds is noted.

"It should be appreciated that what may be intended as a line of smoke... may in fact become an area of

smoke drifting downwind, possibly for some thousands of yards. It will be impossible to forecast the

exact travel in distance or direction beforehand."</pre>

[Wartgamer]

It says 2 minutes emission. Not 5 minutes. Further bombs would have to be fired to maintain it to 5 minutes. Unless in a defensive position, this would rapidly use up a foot units smoke bombs.

2 inch mortar:

9 bombs times 2 pounds is 18 pounds times 30% filling is 5.4 pounds filling.

25 pdr:

2 rounds is 50 pounds times 7% filling is 3.5 pounds filling

Rough math but there is nothing special about 2 inch mortar smoke.

[flamingknives]

Who said it was?

Nonetheless, it's still better than the CM version. Plus the platoon carries more than 9 smoke bombs and 500 yards is pretty significant.

[Wartgamer]

WO 32/10577 Tactical employment of smokeThis table gives "No. to produce 500 yards screen in 10 m.p.h. wind on a cloudy day. On a bright sunnyday or with low or high winds, expenditure of ammunition may have to be appreciably increased."

Again, we are talking ideal conditions.

The general thought is that non-WP smoke is modeled wrong. For some reason, 2 inch mortars are the oft quoted proof.

[flamingknives]

3" mortars would be an equally good example, as would 25 pdrs.

[edit]

Ideal conditions are quoted. Can these performances be reproduced under ideal conditions in CM? No.

[Wartgamer]

3 inch mortar is using WP. I compared 25 pdr. to 2 inch because they are both non-WP type smoke.

3 inch mortar WP is clearly inferior (just compare weight of bombs and assume similar % filling) to 2 inch mortar smoke.

I would say both types of smoke are under modeled to one degree or another.

In addition, the amount of dust/'smoke' generated by larger HE shells is under modeled. TNT generates a large cloud of black 'smoke' in addition to dust.

[ May 30, 2005, 01:52 PM: Message edited by: Wartgamer ]