The changing battlefield air defence (II)

Part I of this series showed how technological progress led to radical changes and how important the effective ceiling difference between light and heavy AAA or (V)ShoRAD and area air defences were.

This time I'll argue that it's become more complicated. The rise of missiles with much more autonomous seekers especially since the 90's (examples AIM-120, MICA, Aster, R-77 - the earlier AIM-54 did not trigger much) brought lock-on after launch (LOAL) into the air war repertoire.

This is hugely important in many ways, but one is of special interest: Nowadays the missile launcher unit does not need a line of sight  to the target or even only the point of intercept any more. It suffices if it gets targeting data that was generated based on distant sensors (networked warfare). The USN demonstrated this (quite late - it should have been possible two decades earlier) with a SM-6 missile that was launched based on aircraft (E-2D or F-35) targeting data only, not using any of the launching ship's sensors.

This unhinges the old two-layered air defence just as much as the advance in airborne ground targeting sensors (imaging infrared, imaging radar) in the 1980's: (V)ShoRAD simply doesn't protect much any more. Well-equipped hostile air power could engage ground targets effectively with impunity. Meanwhile, area air defences with LOAL capability combined with airborne (or land-based forward and thus line-of sight) targeting sensors could defend not only against those ShoRAD-immune threats, but also engage non-line of sight targets (such as aircraft and especially helicopters at very low altitude) that were previously the prey of (V)ShoRAD only.

This leads to two divergent paths for battlefield air defences:

(1) Missile launcher forward, airborne targeting sensor

An AEW aircraft of fighter provides the targeting info, and a mere missile launch container or rack on a vehicle platform with manoeuvre land forces (such as a mechanised battalion battlegroup) provides the LOAL missile with enough chemical energy for area air defence and a high effective ceiling.
The weakness of this approach is in the questionable air support; AEW aircraft could be destroyed or pushed too far back, and fighters would hardly be on station and facing the right direction (few have more than 180° radar field of view) much of the time. Land forces with inadequate air power support - that is, exactly the ones in need of battlefield air defences against manned combat aviation - would find such means of targeting to be unreliable.
The hostile air power on the other hand would still face great risks engaging such land forces, as the network of airborne radar and forward missile launcher would be intact at times and unpredictably so.

(2) Sensor forward, missile launcher more or less "behind"

This is a relevant scenario when you look at a smaller scale. The previous path was interesting with a network of hundreds of kilometres expanse. This second path is rather about the difference between forces rather close to the launcher. A battalion battlegroup or even entire brigade from a country with a poor military budget (such as Romanian land forces, for example) could fight alongside a much better-funded brigade. The low budget force could then use highly survivable sensors (say, Rheinmetall FIRST, RAFAEL Helispot or SAAB Giraffe 1X with on-the-move activity) to provide targeting data and the neighbouring force could use its stocks of expensive LOAL area air defence missiles to protect its brothers-in-arms. Armoured recce and irregulars that operate around a well-budgeted brigade could also benefit from such an air defence umbrella if only they have what it takes to provide good-enough and trusted targeting data.

the old-school (once rather gold-plated) Gepard SPAAG
Germany got rid of its Gepard SPAAG and its Roland battlefield point defence missile systems years ago, and the renewed attention on the actual constitutional mission of defence has led to a renewed interest in battlefield air defence. There are even some bureaucratic requirements; as least some forces need at least a fig leaf of battlefield air defences, and the leftovers of 1980's Stinger stocks are not taken seriously any more (that is, if they exist in Germany at all any more).

There are enough nostalgic people who think of reintroducing Gepard or introducing something similar to Tunguska. There's (justifiably) very little love for the puny LeFlaSys Ozelot which depends on mere ManPADS even though it has a better effective range and ceiling than a 35 mm gun.

I think these thoughts of reviving the 1970's and 1980's concept of battlefield air defences are nonsense. To do such a thing would be wasteful, and if we did it we should at the very least use a less easily-countered guidance principle; laser beam riding (RBS 70 NG with Bolide missile). But such (V)ShoRAD systems have tiny niches nowadays; mostly short exposure targets of opportunity (mostly battlefield helicopters) and keeping low quality air threats at a safe distance. They could also be used by armoured recce to besiege hostile forward air bases (harassing hostile aircraft on their landing approach). These niches are why I mentioned them as a ShoRAD solution for budget brigades.

Radar-equipped LOAL missiles tend to be expensive, and seem to keep becoming more expensive. I wouldn't be surprised if the AMRAAM-ER costs USD 1.5 million per copy even if Germany ordered 1,500 such missiles. (That would be still acceptable if it achieves a mere 10% kill probability against combat aircraft in wartime conditions!) Infrared sensor LOAL missiles such as IRIS-T SL offer much less range (thus also much less ceiling) and are much more questionable for look-down engagements (against very low altitude targets, for example), so their somewhat lower price makes them attractive as complements (also in order to achieve redundancy of guidance principles), but they cannot protect nearly as much as a well-functioning and (hopefully) not-yet countered AMRAAM-ER could protect.
Anyway; all LOAL missiles are awfully expensive and in my opinion too expensive for poorly funded land forces. Countries such as Bulgaria, Croatia, Hungary, Romania, Greece, Portugal, Belgium, Czech Republic and Slovakia should prioritise other equipment and should be able to expect some support from their allies in this regard.

I think the way to go for a rather well-funded European army such as the Heer is to have a multi-role brigade radar, but to not depend on it for battlefield air defence. Other (infrared, infrasound) sensors should complement it and the brigade should have rocket launchers with area air defence LOAL missiles (AMRAAM-ER would fit the bill) to project a sizeable battlefield air defence umbrella that can even protect less well-funded brothers in arms nearby. This was all about manned air threats and comparably expensive air targets, of course. There's more to air defences.



edit: For clarification I'd like to add that I do not mean missiles such as Patriot, ESSM Blk I or SM-2 as "LOAL" missiles. Such missiles lock on their target sometimes long after launch, but they have no ability to lock on targets that are not in line of sight to an illuminator radar - that's a huge problem with their SARH guidance.


  1. I guess you could complicate the picture even further by deploying up to 500 km range ballistic or cruise missiles against enemy airfields. The missiles themselves are definitely not cheap, but I'm sure their cost would be outweighed by their potential to disrupt your opponent. Destroying infrastructure would surely degrade your opponents capability to conduct air operations more significantly than trying to deter individual air vehicles. It is not like you could easily relocate your base of air operations. It would be a very significant logistical nightmare.
    I assume that is the reason why USA is putting more emphasis on missile defence (and air refueling). Being able to keep your air operations going while inhibiting your opponents capability to conduct his operations would surely be the winning ticket.

    1. I wrote about Iskander et al a lot, and so did I about the issue of AEW & tanker aircraft getting pushed back by hundreds of km. This time I focused on a small area and strived for clarity there. I had mentioned the basic thought (consequences if you can separate launcher and sensor, and how area air defence may replace point air defence) before. This post was meant to explain how I arrived at such two-liner remarks.

      Besides; I don't think that BMD can do much against saturation attacks with evasive manoeuvres-flying SRBMs. The intercept missiles are too expensive anyway.The one saving grace is that the Iskander system isn't using contianerised 'wooden rounds', but uses old fashioned dedicated loader and launcher vehicles which makes huge saturation salvoes unlikely.

    2. Well, a salvo of those is 4(HE) or 2(cluster) as recommended for taking on arty positions, at least for Tochka missiles and reloading them doesn't take long. The question is how many rounds there is available.