I made a similar case when I wrote about (against) IFVs, but I'd like to focus on one particular issue this time:
The first armoured personnel carriers served to transport infantrymen or combat engineers to where they were needed (or very close nearby) quickly, and more importantly, with protection against bullets. Hence their open top wasn't a prohibitive problem on flat terrains.
Requirements for protection were increased by much since; protection against large calibre machineguns, protection against single or double-stacked pressure-fused anti-tank mines, protection against 155 mm HE shells exploding at a certain distance, even protection against DPICM bomblets.
Requirements for armament were increased as well, though the rise was from a mere shielded normal calibre machinegun typically to a remotely controlled weapon station with normal or large calibre machinegun or an automatic grenade launcher. The desire to keep the transport vehicle at the drop-off point to give suppressive fires is strong, as is the tendency to think of an APC as a combat vehicle. A combat vehicle that would defend itself on a road march even, with its own armament instead of by deploying the infantry for the fight.
The result was an increase of APC weight from less than eight metric tons to about 30 metric tons, for the same quantity of infantrymen dismounting.
|GTK Boxer prototype|
This led to horrible costs and - since almost all new APCs are wheeled - to horribly high mean maximum and nominal ground pressures, even despite CTIS. Tracked APCs would create headaches regarding long administrative (road) marches, would cost even more and require a greater driver training effort. On top of this the tendency to think of tracked APC as a vehicle that can be upgraded into an IFV is strong.
So the well-protected and somewhat seriously armed APCs are not that mobile offroad, especially not in a reliable way. They may navigate an obstacle course and most will likely not get stuck or roll over on an offroad mission, but the odds that at least one gets stuck or rolls over and requires a troublesome and possibly risky recovery effort are much worse than with tracked vehicles. Many leaders will be tempted to let the infantry dismount or be picked up at different places than with tracked vehicles; the vehicle design tendencies counteract the original intent and purpose.
There's a different purpose, of course. This is also very visible with the non-APC versions of the same basic vehicle type. That purpose is to protect personnel on the march, and even when stationary, and primarily so against artillery and mortar threats. Forward command posts and recovery & repair vehicles, for example. Those would rarely be sent into range of hostile machinegunners intentionally.
Granted, some of such versions are protecting critical or very expensive equipment or are prone to draw fires (mortar carrier, radio jammer), but the overall picture is that nowadays we build armoured vehicles to protect troops in general - regardless of their job description. The MRAP trend showed this in extreme; everybody outside of fortified camps was meant to be protected against even very challenging threats.
This is where an illogic, a lack of consistency, appears:
We cannot protect everyone or even only 90% of the deployed army personnel in conventional warfare. There are more than 1,000 motor vehicles in a brigade of about 4,000 men, the ratio is roughly (slightly worse than) 1:4 among different brigade designs. That would be about € 5 billion per brigade for motorisation alone, plus the mission equipment. To equip six brigades this way would cost twice as much as equipping the Luftwaffe with Typhoon aircraft. This is before we add the expensive true combat vehicles.
Obviously, this degree of protection for everyone is not affordable. Which begs the question why afford it for a fraction only instead? The obvious argument is that for example infantry needs this.
Needs for what? Even the heaviest-armoured APCs cannot withstand modern man-portable anti-tank munitions. Protection against indirect fires is at best moderate, protection against mines is not very important in mobile warfare, and a mine hit will still be a mission killing hit for the squad. The wheeled APCs restrict the choices of drop-off and pick-up points and are rather rarely used for breaking through weak obstacles.
Infantry that accompanies main battle tanks makes the point more obvious: The adequate protection level is the protection level that MBTs enjoy against all portable and indirect fire threats. Neither the heaviest APCs nor any IFVs meet this; only the so called Heavy APCs, HAPCs strive for it at least conceptually.
Meanwhile, why should infantry ride in greater safety than support troops when not in combat? Wouldn't it be most likely to expect that infantry dismounts when a convoy is under attack, compared to mechanics or electronic warfare troops?
This creates a case for giving the infantry no better protection on the move outside of combat than others, and about equal protection to MBT side protection when in combat.
The conclusion ought to be HAPCs for the battle taxi role, and really cheap APCs (essentially medium lorries with cab protection and a bullet- and fragments-proof container on the back) for all non-combat personnel and infantry on administrative marches.
The infantry would leave their lorry-based cheap (less than a million € per copy) vehicle, enter the HAPC, drive by a few kilometres and dismount as close to the objective as bearable.
One company worth of HAPCs would serve three light APC-mobile infantry companies. This battle taxi company would move the infantry (and combat engineers) to the hottest zones, get it out of them and would do so also with wounded personnel (which then gets transferred to a helicopter or cheap APC for transport to a field hospital).
What we have instead is an approach in which only select personnel enjoyed protected vehicles, and then we entered a protection inflation in the 1990's that made their vehicles quite unaffordable. The same protection couldn't be offered to everyone else for reasons of costs, of course - so we unable to offer a consistent approach to protected mobility for the event of conventional warfare. We can do so for occupation warfare, but only because we accepted de facto road-bound protected vehicles for the majority of troops that is not at fortified bases at any one time.
The worst of all; the protection for some of the hottest of missions - such as moving infantry to or into a defended village under fire - is still inadequate, despite the sick prices.
I think this is largely a story about path dependency and inside the box thinking. People were used to see only certain troops in protected vehicles, they got used to the peacetime propaganda/indoctrination about IFVs, they lost conventional warfare out of sight and stared at occupation warfare and its customised recipes.
If we shed all this old garbage and devised a protected mobility strategy from a blank sheet of paper we sure wouldn't end up with the jack-of-all-trades-master-of-none IFVs, or with super-expensive APCs that cannot be combat vehicles but have been partially gold-plated for combat.