Panzergrenadiere (mechanised infantry, somewhat more rooted in German WW2 experiences than other mech infantry) are a 'kind of' infantry branch of the German army and meant to provide the infantry element to our heavy brigades (armour and mech infantry brigades; 2 Panzerbrigaden, 2 Panzergrenadierbrigaden and one Panzerlehrbrigade; -en is plural, -e is singular).
Both Panzergrenadierbrigaden and one Panzerbrigade (being a Panzerbrigade only in name) have the same structure:
2 Mech Inf Battalion
Armoured Engineer Battalion
The other Panzerbrigade has an Armoured Artillery Battalion instead of the 2nd Mech Inf Bn. The fifth heavy Bde is the Panzerlehrbrigade with a unique structure (it has additional training, show and experimentation missions).
Well, that's the planned army structure, a structure of almost historical interest because there's near-permanent change.
Historically there were many more heavy brigades and the heavy brigades were larger as well. Up till if I remember correctly the 70's there was a third Mech Inf Bn in the Panzergrenadierbrigaden, for example.
The typical design for the mech infantry battalions is 2 AFV in the HQ and three companies with 14 AFV each. These units would be mixed down to company level in wartime. The 'pure' battalions of the official structure are - as elsewhere - meant for an easier, more efficient training.
Panzergrenadiere / mechanised infantry are meant to be the infantry component of combined arms warfare (Gefecht der verbundenen Waffen). That's the theory.
Now let's freak out a bit about the actually irresponsible structure that laughs at the nice theory.
(a) Neither the mech infantry battalions nor any other unit in the Bde has any organic mortars. That's outrageous and cannot be explained with our official doctrine.
(b) The Panzergrenadierbrigaden and the one identically structured Panzerbrigade have no artillery battalion, not even a company/battery. The two brigades of the 1. Panzerdivision have an artillery component, but not the other 75% of our combat brigades (2 mech inf bdes, 1 identical armour bde, 2paratrooper bdes the mountain infantry bde). The airmobile (helicopter) brigade with its light infantry regiment has no artillery either.
The combination of (a) and (b) means that the most powerful indirect high angle fire support weapon of an entire German Panzergrenadierbrigade is a 40mm GMW (automatic grenade launcher) of less than 3 km range and it's not meant for non-line of sight use.
(a) and (b) in conjunction laugh in the face of Gefecht der verbundenen Waffen.
Actually, I think it's a good enough justification to fire everyone who bears partial or full responsbility for this.
Combined arms warfare is more than just armour and artillery or mortars; it requires today infantry, armour, artillery/mortars (I claim it requires also electronic warfare if we look at brigades like this, but that's not even close to consensus). It's necessary to have these assets organic in the formation because combined arms warfare requires much training of leaders and staffs, not just supporting attachments in the event of crisis.
Now let's have a look at the infantry component.
(c) Two battalions of each 2+14+14+14=44 IFV/SPz (infantry fighting vehicle /Schützenpanzer) Puma will have a total dismount seat strength of 2 bns x 44 IFVs x 6 infantrymen = 528. That's about as much as a single infantry battalion has.
Maybe I'm very old-fashioned, but I do somehow have the idea that a Panzergrenadierbrigade should have more infantry. In other words; the combined arms qualities of these brigades are in my opinion compromised by their weak infantry arm as well.
This opinion is based on facts:
528 infantrymen (or Panzergrenadiere) is mere theory. Units are rarely at full manning (if ever). It would come close to a miracle if they could be sent off to a crisis with more than 450 men (without cannibalizing external infantry units). The situation could improve within a few months by the addition of reservists, but keep in mind that the predecessors of the Panzergrenadiere had some of the most outrageous casualty rates of WW2. Being sent to one such unit basically meant that the soldiers had on average only a few weeks or months left before they became disabled, prisoners of war, wounded in action or killed in action.
528 seats is pure theory as well. A readiness rate may approach 90% for the first operation in a conflict if the brigade had time for repairs after the deployment march. It's not likely that more than 70-80% of the theoretical 88 IFVs would be available for a second operation considering the losses and technical failures to be expected during the first operation.
I think it's safe to assume at most 70% availability (70% of 88 ~ 62) with a dismount strength of 372 for a third operation.
That's about the point at which even a total concentration of both mech inf battalions of the brigade would likely be unable to remove a qualitatively comparable fresh infantry company from a blocking position in infantry terrain (such as a bottleneck road through woodland) in a useful time frame.
The lack of organic mortars and organic artillery would likely be compensated for by non-organic units, but their ammunition supply is still in question during mobile operations. The artillery can thus not be counted on to decide every fight in closed terrain favourably. A mech infantry bde should be able to solve the problem of a single blocking infantry company without a huge expenditure of artillery ammunitions any way. This is meant to be a major part of the difference between mech infantry and armour brigades, after all.
The assumption of a total infantry concentration is in itself already overly optimistic, of course. Some IFVs would be kept away for security, reconnaisance or other duties. It's therefore reasonable to expect even less infantry at the brigade's Schwerpunkt.
My conclusion is that there's simply not enough infantry, which in turn is in great part a consequence of the high procurement and operating costs of AFVs. The record priced Puma IFV (405 IFV for € 3.1 billion = € 7.65 million /unit) fortifies this problem. Another reason is the high cost of personnel, but as long as you cannot win in ground wars without many human close combat fighters you'll need to pay their price in your deterrence and defence preparation effort.
I think we've moved to a point far below the limit for substitution of infantry with something else (btw, substituted for by what exactly? We don't have that much of anything in our force structure!?)
What's the consequence of a weak infantry component?
Panzergrenadierbrigaden are meant to be heavy formations for independent combined arms combat in pursuit of operational level missions. Their best-suited terrain is meant to be the mixed tank-friendly and infantry-friendly terrain such as in Northern Germany and in the Northeast NATO members. An armour brigade (Panzerbrigade) is meant to be more optimised for almost exclusively open (tank-friendly) terrains and infantry brigades are meant for closed (infantry-friendly) terrains.
A mechanised infantry bde / Panzergrenadierbrigade should be the ideal compromise for actions that require a quick switch between infantry- and tank-centric combat. Tanks would lead the way in open terrain and infantry would lead the way through terrains like settlements and woods before the AFVs take the lead again.
Such infantry actions would typically look like dismounted infantry clearing a road/route through a wood or settlement for safe passage of the vehicles. An alternative would be that the infantry clears hilltops to the left and right, a classic light forces task as described by Xenophon more than 2,000 years ago.
The support by AFVs would typically be limited to one or two vehicles at bottlenecks because of the restrictions imposed by the terrain.
The infantry coponent of such a brigade would therefore be expected to repeatedly and quickly defeat an infantry force of company to battalion size over the course of one operation.
The only alternative to such a demanding requirement for infantry power in the brigade structure is to avoid defended bottlenecks.
Well, amoured recce would hardly be able to sense the difference between one platoon blocking a road through woodland and one battalion, so an infantry-weak brigade could be barred from using such bottlenecks by a flimsy platoon defence. It's actually quite optimistic to expect the armoured recce to perform such risky forms of route recce at all, especially as the old scouting concept is apparently becoming extinct in favour of a stealthy ground surveillance approach once we've lost our last Luchs recce AFVs in a few years.
What does this mean? A heavy, infantry-weak brigade (which has on top of that no organic indirect fire support to speak of) would both be mostly incapable of combined arms warfare without reinforcements AND it would be restricted to open terrain (and thus be very limited and dangerously predictable in its options) without strong infantry reinforcements.
In other words: It's a crappy formation design based on several very mislead trends.
The capability of the two heavy brigades under 1. Panzerdivision command (Panzerlehrbrigade 9 and Panzerbrigade 21, both of which have only about half the infantry strength) to function in mixed terrain regions is even more in doubt.
Let's compare this assessment of the formation suitability for combined arms warfare with the official brigade mission (quote from the website of the German ministry of defence, BMVg):
Kernauftrag der Brigade ist dabei die Befähigung zur Führung des Gefechts verbundener Waffen, zur Führung der eigenen Verbände sowie unterstellter nationaler und multinationaler Verbände und Einheiten im Einsatz.(Core mission of the brigade is the ability to execute combined arms warfare, to lead the own formations as well as subordinated national and multinational formations and units in action.)
Core mission: FAILURE BY DESIGN
I used the Bundeswehr's formation designs as examples and punching bags. The remarks in this blog post are quite easily applicable to many other NATO armies as well, though!
The German Panzergrenadierbrigaden are woefully short of infantry and devoid of indirect fire support - and are thus incapable of combined arms warfare (Gefecht der verbundenen Waffen) with their organic assets alone. Whoever bears responsibility for their structure failed in the principal purpose of setting up a brigade; to create a powerful combined arms formation for independent missions on the operational level of war.
There's a huge gap between the PR spin and reality. I wonder how many of our legislators know about this issue.
P.S.: There are still some people who pretend that Panzergrenadiere should fight mounted and are thus no infantry. That view is detached from reality and a late perversion of WW2 lessons that were meant to solve very specific problems which have long since drastically changed their shape.