Actual U.S. Army Employment of Tank Destroyers in WWII

[Keith]

I just read a Combat Studies Institute document titled "Seek Strike and Destroy: U.S. Army Tank Destroyer Doctrine in WWII". One suprising fact is that TDs were often used in an indirect artillery fire role. In fact, in Normandy 87% of ammunition expended by TDs in VII Corps was fired in indirect missions! Typically the TDs used the same fire support communications network as the regular artillery battalions. In the indirect fire mission the M36 could throw a shell 19,000 yards! The M10 could reach out 14,000 yards.

The second intersting fact is that the TDs were used as the primary weapon to reduce enemy pillboxes with direct fire, firing at the embrasures. During the Sept. 44 assault of the Gothic line in Italy one TD battalion supported the advance by placing rounds through gun embrasures of pill boxes at a range of 1,500 yards.

[109 Gustav]

What a waste of good M36s. Weren't they also brought in against inf holed up in blockhouses?

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Charon doesn't make change.

[Guest machineman]

What they really needed for that was something like the Soviet ISU-152, which had a nickname something like 'Conquering Beast'. The projectile weighed almost 100 lbs. CM2, oh yeah!

[Guest Offwhite]

<BLOCKQUOTE>quote:</font><HR>Originally posted by machineman:

What they really needed for that was something like the Soviet ISU-152, which had a nickname something like 'Conquering Beast'. The projectile weighed almost 100 lbs. CM2, oh yeah!<HR></BLOCKQUOTE>

I believe it's Doubler who gives a couple examples of self-propelled 155's being used in the direct fire role against fortifications. Granted, they weren't designed to be used this way like the Russian SP's were, but I doubt it made any difference to the Germans on the receiving end.

[ScoutPL]

THose are all good examples of why the TD program was scrapped at the end of the war. Very few battlefield commanders understood the role of the TD unit in US Army doctrine. Just another factor of having a citizen-soldier army. Designed to stop enemy armor penetrations, the TD units were very rarely placed in reserve for this role, particularly in Normandy where the terrain was very restrictive to armored thrusts and parrys. the need for armor at the front required their commitment as infantry support units both in a direct and indirect role.

[Guest Germanboy]

The 155mm was used in Aachen in a DF role. The German city commander complained that it was 'unfair' or against the laws of warfare or somefink after the 155 persuaded him to leave his HQ and surrender. An AAR can be found on the US Army's MOUT (Military Operations in Urban Terrain) study website. Try a search on the board for this, I don't have the URL handy.

The reason TDs were used a lot in the infantry support role was IIRC that they were organic assets to the Infantry Division, so it made life for the divisional CO a lot easier than having to negotiate with some pompous AD CO about his assets. I think they had also been training a lot together.

Regarding indirect fire - I would be quite interested in teh actual effectiveness of that. Since the tankers presumably lacked any training, were they actually used for the same tasks as ordinary arty or just for preliminary bombardments where often precision would not matter as much. The ratio of ammo expended on indirect vs. DF is not very surprising, I find. If you are in a indirect fire role you presumably just fire at highest possible ROF, no need to acquire targets.

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Andreas

Der Kessel Home of „Die Sturmgruppe“; Scenario Design Group for Combat Mission.

[This message has been edited by Germanboy (edited 10-27-2000).]

[ScoutPL]

I would be interested in hearing your source for your statement about TO&E. I always thought that the TD battalions were independant just like most of the tank battalions supporting the infantry divisions were. I thought all of the internal AT assets in the infantry divisions were towed.

[Guest Germanboy]

<BLOCKQUOTE>quote:</font><HR>Originally posted by ScoutPL:

I would be interested in hearing your source for your statement about TO&E. I always thought that the TD battalions were independant just like most of the tank battalions supporting the infantry divisions were. I thought all of the internal AT assets in the infantry divisions were towed.<HR></BLOCKQUOTE>

Please not the disclaimer in my statement. I thought that came from Dobler 'Closing with the enemy', but I can well be wrong. I am much better on UK TO&E. It has been about 8 months since I read him, and the books is in storage far away now.

Having said that - I know that some of the independent Tank batallions were sort of permanently assigned to IDs and developed quite good procedures of working with them. If the TD BNs were nominally independent too, maybe they ended up being assigned more or less permanently?

Damn I have to get my books out of storage.

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Andreas

Der Kessel Home of „Die Sturmgruppe“; Scenario Design Group for Combat Mission.

[This message has been edited by Germanboy (edited 10-27-2000).]

[Keith]

ScoutPL, you are correct on the contradiction between how TD battalions were initially envisioned to be used vs. how they were actually used. According to the document the TD battalion was designed to be kept independent to quickly counter concentrated armored thrust by german panzers. The TO&E of TD battalions reflected this in the sense that they had no organic infantry or artillery. But the reality was that the Germans used combined arms tactics, never sending their tanks into combat without support. Thus the whole philosphy behind the TDs were flawed from the start. Nearly all of the American armor commanders (including Patton) thought that TD production should be scrapped in favor of up-gunning the main battle tanks.

With regard to the TDs secondary roles as infantry and artillery support, this was something that was clearly not envisioned by creators of the TD units. TDs were successful in this role and typically a TD battalion would be attached to an infantry division. The TDs would then be parceled out with one platoon per an infantry battalion. As far as indirect artillery is concerned the TDs were used in this role for interdiction purposes and were quite accurate and in fact out ranged the 105mm howitzers. During one major river crossing the TDs first provided direct fire support against the far side of the river. Once the infantry crossed and pushed beyond the range of direct fire support the TDs switched to indirect fire support with the help of TD indirect fire spotters attached with the infantry.

[Jeff Duquette]

Scouts right from what I have read. Although US Army Infantry and Armored divisions in ETO had organic towed anti-tank assets (mostly 57mm’s), SPTD’s and many towed TD’s (mostly the towed 3 inch or towed 76mm) were formed into independent battalions. In many cases, for reasons of cohesion and inter unit corporation (i.e. corporation between divisional maneuver battalions and independent TD and Tank battalions) independent SPTD, TD, and tank battalions became kind of pseudo-organic in that they tended to be attached and remain with the same division for long periods of time.

As far as the indirect artillery employment of SPTD’s I recall from “Seek, Strike, and Destroy” that M10's were relatively effective in this role in North Africa. After there battlefield success apparently the Tank Destroyer School set-up formal indirect artillery fire training as part of advanced individual training for TD crews. The problem with the indirect fire role of M10's was apparently the excessive barrel ware resultant from firing in an indirect mode. This may account for some of the less than stellar Armour penetration characteristics of M10’s in ETO. Seems to me I read something regarding barrel ware and reduction in muzzle velocity.

[PeterNZer]

I believe there was a sight that could be attached to the tank gun for its indirect fire role. I guess a compass and a pendulum arangement

PeterNZ

[Blindicide]

"During 1940-41 German armoured employment in Europe forced the (US)army to adopt strong antitank countermeasures which eventually led to a separate tank destroyer force.Provisional AT battalions employing artillery usable against tanks (which was withdrawn from organic assignment to armies corps and divisions) were activated commencing 24 June 1941.On 3 Dec 1941 all antitank battalions were redesignated tank destroyer battalions to reflect their "offensive spirit",the old infantry AT battalions were additionally renumbered,and all traditional association with their branch of origination (field art,etc.) was removed.

In 1942 the army anticipated massed concentration of TD battalions against enemy armour which called for a tank destroyer brigade for each field army.Combat experience in 1943 negated these expectations.Even the group HQ's were scarcely used overseas,as TD battalions were commonly attached directly to divisions beginning in the African and Italian campaigns and operated independantly in the Pacific.Only two brigades were authorized,one inactivated in early 1944,the other saw limited employment in France.

Initially three types of TD battalions existed:Light Towed,Light Self Propelled and Heavy Self Propelled.It rapidly became obvious the 37mm AT gun was too weak for its intended role and the army converted all of its TD battalions during 1942 to one type-Hvy-SP with 24 75mm guns mounted on half tracks.The high silhouette of this vehicular arrangement and unsatisfactory performance in N.Africa prompted the army to return to the towed gun which could be dug in with only its muzzle protruding.During 1943 the SP battalions in the US were gradually converted to towed but none were used in combat that year.In Nov 1943 the army decide that half the battalions would be self propelled,equipped with M10's with a 3-inch gun and half would be towed with the M5 3-inch towed gun.In Jan 1944 the War Department alerted theatre that a more mobile carriage,the M18 with a 76mm gun was in production and that an M36 model with a 90mm gun would be available as soon as production schedules permitted.Since all the SP battalions were already equipped with the M10,it was decided by theatre to refuse the M18 to simplify maintenance and supply and await the arrival of the heavier M36.

Soon after the operations began in France,it was evident that the M10 was inadequate against certain German armour,and that the advantages of a self-propelled weapon greatly exceeded those of a towed weapon both on offense and defense.Action was initiated to speed up procurement of the 90mm M36 carriages,and early shipment of M18's was requested to Europe.The War Department was further requested to equip all M10 battalion scheduled for later arrival to Europe with M36's preferably,or M18's prior to embarkation.In Aug 1944 the first increments of M36's and M18's arrived in France and the SP battalions began to re-equip with M36's and M18's accordingly,and as many towed battalions as possible were converted to SP by being issued the replaced M10's.By the cessation of hostilities in Europe the 12th Army Group,for instance,had 45 TD battalions of which 27 contained M36's,13 had M18's,6 were equipped with M10's,and only 4 were towed.The ratio of 50% towed at the start of the campaign had changed to 9% towed,91% now being self-propelled.Because TD battalions were in general phased in faster than divisions,the ratio of TD battalions to divisions was usually better than one to one.

TD battalions,especially on the mountainous Italian front which precluded massed armour,increasingly operated as reinforcing artillery.The decline of German armour during certain periods of the fighting in France and Germay also caused this role to prevail at intervals."From Shelby L.Stanton's Order of Battle US Army WWII.

Apologies for the long post but I think that just about answers everyting above.

[Keith]

Incidentally the main reason that TD battalions were broken up and parceled in direct support of the infantry was the fact that the infantry battalions lacked an AT gun capable of knocking out most German tanks. The 57mm AT gun was inferior and no infantry commander was willing to have his troops be overrun by armor while the TDs waited in the rear on the reverse slopes of hills for the armor to come to them.