Reconciling Active Protection Systems with the SDSR

Active protection systems (APS) are electronic and radar-based devices that interfere with the flight of anti-tank missiles and rockets. APS can be grouped into two main categories; soft-kill and hard-kill.

These types have differing capabilities; however, some systems offer a combination of both. Soft-kill systems can disrupt guided weapons using various methods, including chaff, opaque smoke or interference with the laser or IR guidance system of the missile itself.

These measures aim to alter the missile’s trajectory so it either misses entirely, or strikes the vehicle in such a way as to mitigate its destructive potential.

Hard-Kill systems, such as the Israeli Trophy and Russian Drozd, can destroy an incoming missile (guided or unguided) in-flight with short-range explosive munitions or canister blasts.

All APS rely to some extent on radar or direction-finding technology to track and classify incoming threats, as well as provide direction information to the crew of the vehicle on which it is mounted.

The current APS which QinetiQ is contracted to test is the Multifunctional Self-protection System (MUSS), a soft kill system developed by German defence manufacturers. Although currently under testing while fitted to Challenger 2 main battle tanks, QinetiQ hopes to demonstrate the viability of attaching the MUSS to other British armoured vehicles.

British armoured protection has, for the most part, proven satisfactory in recent conflicts. It performed well in Iraq and Afghanistan, particularly against attacks by shoulder-launched munitions.

The latest-generation Chobham (Dorchester) armour fitted to the Challenger 2 has proven almost impenetrable over the past two decades, surviving in some engagements a prolonged attack by both RPGs and anti-tank guided missiles (ATGMs).

Similarly, the Warrior infantry fighting vehicle has resisted RPG strikes well enough, particularly after the application of various up-armouring kits in theatre. By all accounts, the primary danger to British armour in recent years has been improvised explosive devices and landmines.

However, with the 2015 Strategic Defence and Security Review (SDSR) placing the Warrior and Challengers at the core of its armoured brigade concept, it is not unreasonable to wonder if the excellent performance of British armour will continue into the 2020s.

A Challenger 2 was notably penetrated by a tandem shaped charge RPG-29 strike in 2005. With the proliferation of this type of advanced RPG increasing, it is questionable if traditional armour and a soft-kill APS would be adequate to defend against the full spectrum of future threats.

The prospective conflicts outlined in the SDSR may involve a significantly more advanced, and sustained, anti-armour threat than the opponents faced by the British Army in recent years.

The hybrid or state-based threats the UK might face can be assumed to have significant access to modern variants of the RPG family, and modern anti-tank guided missiles (ATGMs) such as Russia’s 9M133 Kornet. Potential combatants may offer stubborn resistance in unforgiving terrain, necessitating the deployment of British armour for extended mounted operations.

In such operations the adequate protection of armoured platforms is a prerequisite to success. While Britain has deployed armour to hybrid and urban combat in Iraq, these operations have been rare since the mid-2000s. However, the experience of other nations against committed hybrid combatants can be used to provide experiential lessons.

As demonstrated by the Russian and Israeli experiences of hybrid warfare, a semi-organised opponent armed with late-model RPG variants and ATGMs can prove a stubborn anti-armour combatant.

During their first advance into Grozny in 1995, Russia lost 105 out of the 120 Armoured Fighting Vehicles (AFV) it deployed to enter the city. High-angle attack by RPGs proved a significant threat, striking the thinner top armour of the Russian AFVs.

Russia was unable to engage at sufficient range due to the retreat of the Chechen fighters into Grozny’s urban interior. Russia countered the proliferation of anti-armour missiles with indiscriminate and sustained air bombardment, as well as the use of flamethrowers and grenade launchers, hoping to destroy the Chechen fighters without putting their tanks at risk.

To compound this issue, Russian infantry losses were very high as they were forced to shoulder a disproportionate amount of the clearance workload.

While this enabled more successful penetrations by Russian armour, such wanton destruction in an urban environment is highly unlikely to be politically acceptable to British decision-makers.

Today’s British Army enjoys significantly greater technical and professional capabilities than the military of the Russian Federation in 1995. However, the nature of the threat in Chechnya is not dissimilar to what British troops might face in the future. An entrenched opponent whose anti-armour weaponry was sufficient to penetrate the passive armour of the mounted combatant.

The Israeli Defence Force is perhaps a more apt comparison, with its structure and platforms being similar to those of the British Army. During recent operations, Israeli armour has been called on to provide support in urban combat against a hybrid opponent, and in several cases came under sustained attack by advanced ATGMs and RPGs.

The 2006 war in Lebanon saw IDF Merkava tanks destroyed or seriously damaged by Hezbollah missiles on about 20% of hits. In the eyes of the IDF, the 2006 conflict restated the case for heavy armour in urban warfare, with the Israelis renewing production of Merkava and Namer heavy armoured vehicles in the following months.

The introduction of the Trophy hard-kill APS followed shortly thereafter, with its first successful interception of an ATGM occurring in 2011. The ability of armoured vehicles to counter hybrid opponents, particularly in urban warfare, appears to rely extensively on effective protection against shoulder-launched and man-portable munitions.

 Along with this, in both Grozny and Lebanon the experience of hybrid warfare restated to the armoured combatant the importance of heavy armour in modern operations. Thus, it is clear that effective protection of armoured vehicles is an indispensable feature of modern mounted combat.

While the MUSS APS currently undergoing testing with QinetiQ offers protection against guided missiles, it cannot defend against unguided weapons such as RPGs. Even the most advanced passive armour on British vehicles has proven potentially vulnerable to such weapons.

To compound this issue, RPGs and other unguided munitions continue to develop in terms of their ability to penetrate armour. Along with this the Warrior and Ajax vehicles that will form a great deal of the Army’s future strength have significantly less protection than the Challenger 2.

Presuming that British armour will achieve an acceptable level of protection with purely passive measures would be unwise, given the potential for a more advanced missile threat in coming years.

As noted in Andrew Hardie’s article Offensive Defence: The Limitations of Armour, increasing the thickness of vehicle armour or attaching applique is not always tenable, as the problems associated with increased weight begin to tell.

A hard-kill APS offers an alternative method of increasing armoured protection with less weight, against both guided and unguided munitions, particularly for more lightly armoured British platforms.

Along with these technical abilities, APS offers potential morale enhancing effects, in ensuring a sufficient level of protection to foster confidence in individual soldiers even in the face of well-equipped opponents.

Although a hard-kill system does pose some risk to dismounts through its use of explosive munitions, this could also be said of the Explosive Reactive Armour (ERA) that was mounted on the Bulldog, a British armoured personnel carrier deployed to Iraq in 2007 and Challenger 2 side-skirts.

Furthermore, the risk to dismounted personnel in a rocket attack is already significant, and any danger from an APS could probably be offset by the gains in safety amongst vehicle crews. Given that the SDSR envisions a diverse range of threats, it is important to ensure that British armour is capable of offering the protection necessary to counter them.

An APS fitted to British medium armour could go a long way towards fulfilling this requirement, improving the survivability of mid-life platforms in the face of modernised anti-armour missiles.

Recent experience shows the clear dangers for armour operating against hybrid opponents, and their survivability could be improved enormously by serious attempts to counter the modern missile threat.

James Shinnie is an Intern in Military Sciences at RUSI.

Banner image: An Israeli Merkava Mk 4M main battle tank with Trophy Active Protection System (Windbreaker) during the 2014 Protective Edge Operation in Gaza. The APS system was introduced after the massive hit Israeli armour took in Lebanon in 2006. Courtesy of IDF Spokesperson Unit/Wikimedia.