2009/12/18

Field fortifications: Angle bastion, Parfox and the MG4(2)

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The German infantry squad of the 30's and WW2 was built around a multi-role machine gun (medium machine gun, MMG); the MG34 or MG42 or another machine gun if the unit was poorly equipped with an old or captured machine gun. The other guns were mostly bolt action rifles, K98 - with a practical rate of fire of about 15 rpm under training conditions. Submachine guns were quite rare until mid-war and didn't influence the infantry doctrine very much. The result was that the machine gun made up about 80% of the squad's firepower. Squad fire tactics had to ensure a maximum exploitation of its potential.

Now think of the combination one 80% firepower weapon plus almost a dozen 2% firepower weapons. It was obviously necessary to site the machine gun for the best possible field of fire to avoid fatal quasi-dead angles.

This consequence of a specific squad TO&E defined infantry tactics, especially tactics in regard to field fortifications. It became imperative that the machine gun had a great angle of fire. A restricted field of fire (like only 90%) was only tolerable in the context of a platoon position, not in the context of a lone squad position.

The introduction of the G3 battle rifle (7.62x51mm, 20 cartridges magazine, about 30 rpm practical rate of fire with single shots) didn't change the German practice very much because the MG3 (a modified MG42) was still the centerpiece of the squad. Many of the Wehrmacht's quite proven infantry tactics were re-introduced during the late 50's.

The Bundeswehr adopted the maxim "Wirkung vor Deckung!" (effect over cover; effect of fires is supposed to be more important than cover) and placed a strong emphasis on a great field of view and fire. That was in regard to the infantry - again in part a consequence of having only one machine gun in the squad (despite its reduced share of the squad's firepower).

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The U.S.Army developed the parapet fire position for infantry during the Vietnam War and had pretty much proved its potential superiority in 70's experiments (summary here).


A frontal parapet provided frontal cover, reduced the suppressive fire effect on the defender and in net effect reduced defender casualties greatly ("Parfox" position). The effect was further increased as thermal sights became common main battle tank equipment during the 1980's and all-round defensive positions were easily identifiable due to their lack of cover and concealment against frontal observation. The parapet/flanking fire design also turned around the theory behind ambush reaction drills, but that's another story.

This parapet defence uses a centuries-old principle that was especially visible in the late 15th century Italian invention of the angle bastion (Renaissance age).


This fortress design protected the defensive guns from direct fire by setting them up for flanking fire only. One tower's (or bastion's) guns were defending the neighbouring tower/bastion with flank fire. The guns were meanwhile protected against frontal fire by strong walls.

The disadvantage of such a (pure) parapet defence is that positions depend on each other. That's obviously a very risky affair if you've got only one machine gun. The Americans introduced the M249 SAW light machine gun and were able to field two per squad - a necessity for the effective use of parapet defences on the squad level.

The German army (Heer) doesn't place nearly as much emphasis on flanking fires with frontal parapet (although both elements are in some use) because it sticked in theory to "Wirkung vor Deckung!".

It has finally and belatedly moved from a single MG3 per squad to the 80's concept of two 5.56mm MG4s per squad.
The development of a 7.62mm MG4 version and recent small own and allied wars experiences may change that again, though.


Variations of the Parfox position are often preferable and this is one of many reasons why the Bundeswehr's maxim "Wirkung vor Deckung" needs to be ditched in favour of a less simplistic understanding of infantry survivability, suppression and firepower.

It's probably even too late for a simple update with Parfox - we have likely missed an entire generation of field fortification tactics and are likely in serious need for a large step ahead in order to compensate for the increased performance of sensors and accuracy of support fires, but that's a blog post for another day*.

Sven Ortmann

*: I broke the field fortifications stuff into manageable pieces because there's really too much to write about for a single post.
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1 comment:

  1. The Bundeswehr has too much US Army influence and its military skill is nowhere near that of the Heer in 1941.
    Mickmame: Assymetrico

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