"How attritional is a successful attack?" Topic

If two companies of infantry assault one company of infantry along a 600m front, assuming the defenders are prepared and both sides have appropriate support, and all else being equal (even though it never is) what chance do the attackers have? How many men can they expect to lose if the attack succeeds? How much does this impact their ability to continue fighting that day?

Same thing, but three to one instead?

It's a broad and contrived question I realize and impossible to generalize across multiple theaters of war, but I'd love to hear some opinions. Throw in as many qualifiers as you like. I'm working on a set of division level rules and toying with different models for the attack.

Anthropicus,

Sounds like fun, I'll take a shot. With what you wrote, and assuming things went well for the attacker, but not too bad for the defender, and the attacker's objective was geography, not destruction of the enemy force, I'd say the attacker takes 10-15% casualties. The defender takes probably 10% casualties, realizes he needs to get off the attacker's objective, then takes another 5-10% casualties while withdrawing.

That's best cases scenario for an attacker against a defender that's worried about force preservation, which is usually not a concern in war games but almost always a concern in real life.

There's my opinion.

V/R,
Jack

It really really depends on what you mean by appropriate support for the defender – if that includes properly sited defensive arty then the attackers may never take the position with two to one, three to one would be iffy.

Somewhat of a tangent, but a number of accounts I have read (mostly Western Front, 1944-5) describe either the attackers or the defenders being defeated by the support weapons. The impression I get is of infantry being the troops that marked the front line, with the mortars, artillery and in some cases aircraft being the things that determined how that line moved, or did not.

In a tabletop game: 50% if it was an easy win, 80% if it was a close run thing :-)

In real life, 10-15% seems a fair enough stab as Jack suggests.

There is operations research which covers this stuff. The success or otherwise of the attack mainly depend on the degree of entrenchment of the defender, the amount of preparation by the attacker and overall force ratio taking account if support weapons. Casualties are principally a function of whether the attack succeeds or not, and in some environments, can be very heavy indeed for the loser. It should be noted that casualty levels are also a logarithmic function of numbers, so more attackers equals more dead attackers, although not a linear relationship. Wargames rules which do not take account of target density model this very poorly.

I would recommend both Murray's "Brains and Bullets" and Rowlands "The Stress of Battle", both include exhaustive analysis of tactical outcomes, and Murray examines the effects of casualty rates on overall unit effectiveness.

Useful sources for battalion sized outcomes are the combat outcome charts in the 1956 British Army War game, which also includes indicative loss rates.

I'm on the wrong device to post links and stuff I'm afraid. In a different environment, I'll have a go at actually answering the question!

Great answers! The points about artillery have got the gears in my head turning, defensive bombardment should certainly be factored in there.

Martin, that's exactly what I'm looking for, I'll try to check out those references.

I'd like to specify that I was looking at a three to one ratio for our successful attack, and that the casualties to each side were probably almost exclusively from supporting fires, with the defenders withdrawing prior to the two sides' infantry even really coming to grips, though a small percentage of each sides' casualties is probably due to organic mortars and machine guns.

I would also like to point out that my understanding of unsuccessful assaults is usually due to the defender's supporting fires breaking up the attack at or just past the line of departure, or even in the attacker's assembly area! I've read of numerous accounts of that by the Allies in Italy and the Brits in Normandy. Don't recall reading that about the Societs, though I have read German accounts of being tactically surprised by them on several occasions, with the Germans specifically mentioning the ability of Soviet infantry seeming to just 'pop up' (similar to US experiences in Korea and Vietnam).

Martin always has great references, I hope my guesstimates above aren't wildly off!

V/R,
Jack

Still away from many references I'm afraid, however I do carry a handy chart with me showing the probabilities of success for various force ratios. I'm a bit odd like that.

Anyway, you may be gratified to know that according to US Army operational norms, a three to one attack has the following chances of success.

Meeting engagement, in excess of 85%
Hasty attack vs hasty defence, around 60%
Hasty attack vs prepared defence, 30%
Hasty vs fortified defence, 20%, if that
Prepared attack vs hasty, 70%
Prepared vs prepared defence, 50%
Prepared attack vs fortified defence, 30%

No loss rates in my travel folder I'm afraid, but I do recall Dupuys average divisional daily loss rates in offensive operations, 3.5% for the attacker and 2.5% for the defender (with various mods). Note that these are rates not levels, so if you have 30000 men engaged with 10000, the attacker is losing 950 men per day, whereas the defenders are only losing 250 per day… these rates are highly variable depending on force size and force ratios adjusted for posture and terrain, see Numbers, Predictions and War for more detail, but it may be at way too high a level for battalion sized engagements.

OK, finally got some books out. The trouble with extrapolating from the various models and analyses to the specific question is that the originals have specific contexts and purposes which aren't easy to encompass on a forum post.

Rowlands is principally interesting in measuring combat degradation, while Murray is interested in quantifying tactical factors in real combat.

A couple of things which may be useful, Rowlands analyses a series of 3:1 attacks with varying levels of armour support. Infantry weapons are calculated as MG equivalents, 9 rifles = 1 MG, 1 81mm mortar = 3 MG (or 27 riflemen), artillery effects are based on density of HE delivered and duration of bombardment.

A pure infantry assault with no prep bombardment at 3:1 against a prepared defence yields attacker losses of around 30%. Mix in a troop of tanks per company and losses drop to 10% (or add in equivalent fire support- artillery or mortar battery), mix in a squadron of tanks per company (or equivalent) and losses become negligible, 1-2%.

In the 1956 Operational rules (based on WW2 and Korean experience), loss rates are given in Appendix C for battalion sized units, with a spread of values.

Infantry defence:

success, between 5% and 35% losses, the mode is approx 15%
failure, 15% to 70% (ouch), mode is 35%

Infantry attack:

success, 0% to 25%, mode is around 10%
failure, 5% to 35%, mode is 15%

Armour losses tend to be higher

success, 15%
failure, 40% (which Murray estimates for later conflicts to be more like 65%).

Unit effectiveness ((battalions)

0-20% losses, no significant effect
20-40% losses, significant effect, halves combat effect
40% to 75% losses, unit is combat ineffective and requires reorganisation. If attacked and unable to retire will be overrun and completely destroyed.
75% unit wiped out.

This is in the context of a week long Corps level operation.

Murray notes that for more modern units, if a (battalion) suffers 10% losses in a single day, particularly if from artillery fire, its combat effectivness is seriously reduced if not rendered completely ineffective, until it reorgs. On average, in general, subject to some variation etc.

So basically Jacks estimates are spot on, assuming a moderate amount of fire support for the attack. Hardly surprising:)

Super helpful.
Thanks for sharing Martin.

Well, as I said, approach extracts from individual sources without context with caution, bear in mind that 15% losses fir a battalion can translate into 150 dead or wounded riflemen, which is five platoons worth…

yeah, when we zoom into a microcosm, the scales get more and more difficult to apply.

I wonder if typically, for a battalion, those losses would be relatively evenly distributed or if a few companies would bear the brunt of them.

Usually one or two companies lead the attack and I imagine they'd be disproportionately represented in the casualty lists.

The concept of attrition is an often ignored factor of a war game attack. It I'd clearly a factor and can be seen at the lower level where men are lost on both sides during an engagement. At a higher mass combat level, several rules ignores the factor. It is also a common avoided issue in board games as well. Only in a step reduction system will any attrition aspects.

Your frontages vs. forces ratio are a bit off in term of attacking.

Yes, a German company might be expected to cover that 600m frontage on defence, but it'll be attacked by a much larger force than two companies. On that frontage it should expect a British battalion (3-4 companies plus heavy support) attacking, often in a broad wedge formation.

Martin offers the right stats for losses in his post.

In a full up defence you would expect about a platoon on a 500m frontage. D-day landings were againast more like a platoon per mile but with lots of defences.

The whole issue is about co-ordination and if you have it. The manuals describe arilleries job as to suppress and fix in place. Part of an attackers artillery barrage is to prevent the enemy leaving by suppressing an area behind their positions so that the attcake can prevent them running off.

The defenders aim is well as preventing the attacker moving up ont suppressed defences. To some extent he who runs out of Artillery first loses. Part oif the late war issue was to have APC's that would allow attakers to move through the enemy barrages with minimal losses.

Thus losses ar a function of how well both sides do. The big losses come if and when it becomes a close in battle as fo example in an urban area where the other arms are less able to support. Near 100% losses for defenders that cannot escape when prisoners are included.

Against prepaired defences including pill boxes you may need a lot more than two companies to take out a company. At that density the defender will be perhaps 1 to 2 km in depth with mines, ATG support and Prepared Artilletry it may take more than 1 day. D-day only got 1 to 2 km off most beaches.

Michael Doubler in his Closing with the Enemy Argus 2 to 3 percent per day average casualties for US Army in NW Europe
David Glantz in Barbarous Derailed has similar numbers for the Germans in the summer 1941
However, individual battles can vary, but the long term loss rate, is low. The first wave at Omaha had much higher lossrs, but averaged in with the succeeding waves, altogether 5 percent
Also it depends on terrain, such as the huge Soviet losses at Best Litovsk or Sevastopol, or the Germans at Stalingrad, it's the situation, the siege, or in the running away. Remember that combat loss statistics for many lengthy battles/mini campaigns do not separate out days of intense combat from days of comparative inactivity. At the appendix to David Chandlers Military Campaigns of Napoleon is a list of many battles with losses presented as ratios, but these were mostly one day events, and in a different combat setting than WW2 so the casualties are higher as the battle was resolved in one day using weapons and tactics that called for heavier losses in the short term. Compare Antietam with Omaha in percent of losses of immediate forces engaged, Antietam is much higher despite the abundance of automatic weapons and heavy artillery at Omaha.
And as each battle is different, a comparison of say Soviet tank losses at Brody to Kursk.while seemingly similar has to include the poor Soviet tank maintenance at Brody as a factor in their losses to the Soviet losses at Kursk due to factors other than breakdowns. As too many battles have very different reasons for casulties, a quick scan of losses and percents obscures the real reasons for light losses here and heavy losses there.

One of the interesting things is losses to Artillery. It is an oft quoted truism that Artillery caused many more losses than any other weapon. This leads many wargamers to belive that this by definition makes it the Queen of the battlefield. It is not the main killer on the battlefield. It is the biggest killer in a war as it kills a few every day due to shelling of rear areas where the troops are out and about. This mounts up. Attacks happend infequently so the average loss is not high and defenders are offten relatively well protected from the worst effects of artillery. so other weapons are what carries the day. Again this makes estimating actual attack losses very difficult.