Which ground-based air defence (GBAD) solution is best?
Radar-guided? Laser-guided? Long-range? Short-range? There are a range of options when choosing a missile-based GBAD solution. So, which system is the most effective?
Ground-based air defence (GBAD) is one of the most powerful strategies available for armed forces defending territory and combatting aerial threats. Having the ability to engage and destroy aircraft, drones and missiles using munitions fired from the ground can stop the enemy from achieving aerial dominance – and turn the course of battles and wars.
And so, it would be extremely convenient to be able to nominate one type of GBAD system as superior to all others. To say that a particular missile system or a certain operating range was optimal and that all other systems were redundant.
However, reality – like combat situations – is complex. The truth is that no single GBAD solution has all the attributes needed to be considered ‘the best’. It’s only when a range of ground-based systems, each with individual advantages and disadvantages, are used together that armed forces are able to fully tame the aerial threat.
So, what are the different types of GBAD systems available? What attributes does each bring to the table? And how can they be used together to erode air dominance?
While the term ‘ground-based air defence’ broadly includes things like barrage balloons, camouflage and jammers, most ‘active’ GBAD systems aim to destroy aerial targets through the use of either missiles or shells.
A useful way to understand the different solutions available is to consider how they lock onto targets. In general terms, the systems used to ensure the missile or projectile connects with its target can be divided in four categories: non-guided; radar guided; infrared guided; and laser guided.
Non-guided systems are the perhaps the simplest option. These typically involve rapid-fire guns that are used to fire conventional shells – such as armour piercing rounds – at aerial target. With a barrel larger than a machine gun but smaller than a field gun, they can be used to bring down aerial threats such as helicopters and drones. A human operator aims at the target with the help of electro-optic tracking. The shortfalls of such systems include limited range (usually below 3,000 metres, limited accuracy and poor tolerance for managing targets that swerve or manoeuvre off course.
Next come radar-guided missile systems. These rely on the use of radio waves to establish a clear radar picture of exactly where their intended target is located. With ‘active radar homing’, the missile itself is fitted with a radar system which helps it track the target and make adjustments to its own flight path to increase the chance of an impact. With ‘semi-active homing’ systems, the missile use a passive detector to pick up a radar signal that have been reflected by the target. This signal is generated by an external source, normally a tracking radar deployed at the same place as the missiles launch system Both approaches can be extremely effective in destroying targets at ranges of many tens of kilometres, regardless of weather conditions. However, radar-guided systems are susceptible to radar jammers fitted to aircraft. Such jammers interfere with the radar signal, making the missile lose sight of the target, rendering it useless.
Next come infrared-guided missiles which rely on a so-called ‘passive homing’ approach. Such missiles make use of the fact that aircraft engines typically produce a great deal of heat, creating a distinctive thermal signature. Infrared sensors fitted to the missile itself help it to identify and lock on to the target, adjusting its flight path whenever the target charges course. As with active radar systems, infrared-guided missile are suitable for “fire and forget” use and will keep pursuing the target independently once fired. However, like radar systems, they can be fooled by countermeasures. Flares dropped by aircraft will create new heat signatures that confuse such missiles and put them off course.
Command Line Of Sight
The final approach is laser guidance. Far less common than radar and infrared systems, laser-guided systems rely on a ‘laser guidance beam’ emitted from the point of fire. This laser pointer remains firmly locked in the target as it moves through the sky and a laser detector fitted on the missile enables it to follow the beam. An onboard processor makes adjustments to the missile’s flight path using control fins to ensure a successful impact.
The leading example of a laser-guided GBAD solution is the Saab RBS 70 system. Man portable (MANPAD), it can be assembled and ready for use in just 45 seconds and is highly effective at ranges of up to nine kilometres. Importantly, unlike radar guided and infrared guided missile systems, RBS 70 missiles can’t be fooled by radar jammers or flares. As long as the laser beam remains on the target, the missile is likely to do its job.
However, even outstanding weapons have some limitations. While radar and infrared systems can be fire and forget, the RBS 70 NG cannot be refired until the previous missile has found its target.
The power of diversity
While each GBAD guidance system has its strengths and shortcomings, combining them can produce truly outstanding results. In situations where multiple missiles are likely to be required in quick succession it can be useful to have fire-and-forget solutions at hand. At the same time, in the likely scenario that jet fighters will form part of the aerial threat, a solution that is effectively unjammable, such as the RBS 70 NG, brings huge advantages not available to missiles with conventional guidance systems. Meanwhile, gun systems may have a role to play in defeating simple aerial threats like drones and helicopters.
The same rule – that a diverse range of solutions brings the best results – also applies when one considers range.
Different ranges – and strengths
Ground-based air defence is commonly divided into three main ranges: short range for systems capable of bringing down targets between zero and 10 kilometres away; medium range for solutions effective up to 50 kilometres from the target; and long range for systems capable of covering more than 50 kilometres.
Long-range systems – one example is the Patriot system from the United States – are formidable weapons. They have large coverage areas and a proven ability to destroy a variety of aerial threats, including jet fighters. But long-range systems also have a number of weaknesses. The relatively high cost of both the launcher and missile make long-range systems a poor choice of weapon for destroying small, disposable drones – an increasingly common weapon choice among the West’s enemies. Their reliance on radar guidance creates other issues. For one, the curved nature of the earth’s surface creates radar shadow zones when radar systems are used to scan locations many kilometres away. This means that if an aerial threat remains close to the ground, say, less than 1000 metres, it can potentially avoid detection by a distant long-range GBAD system. Meanwhile, modern fighter aircraft very often carry sophisticated countermeasures to manage the threat from radar-guided missiles. Long-range systems are also very slow to deploy due to the large sized of both the launcher and missile.
Medium range GBAD systems share many of the strengths – and also many of the failings – of long-range systems. A medium range solution, as exemplified by the Russian BUK M2 system, might have an extended range of 45 to 50 kilometres and be highly effective against a wide range of aerial threats. But again, the expense of such systems tends to be high. Again, the curvature of the earth and radar shadow are problems when acquiring targets over long distances. And, once again, radar jamming of missiles and relatively slow deployment times are issues.
Short range GBAD systems have limitations, too. They don’t have the long reach of bigger systems, with some capped at just 3,000 metres. Many use infrared missile guidance systems which can be fooled by the countermeasures on military aircraft. But they bring benefits in terms of agility and fast deployment and don’t suffer as much from the radar shadow effect as long-range systems. A number of short-range systems are man-portable meaning they can go where no long-range system could ever go – off road, into wilderness areas, and onto roof tops in highly built-up urban areas. The smaller size of short-range GBAD systems means they are less likely to be sighted during satellite reconnaissance, providing an element of surprise that can prove lethal to enemy aerial threats.
Additionally, the RBS 70 NG system brings a number of benefits other short-range systems don’t. It is effective to an impressive nine kilometres, creating a deadly threat to any aircraft that dares drop within range. As previously mentioned, it also uses laser guidance, making in impervious to jamming.
Layered air defence
The secret to achieving truly effective air defence is to use these different systems in concert and with other technologies to create layered aerial defence.
Long-range systems can be used to provide a solid defence backbone, helping to monitor and secure large geographic areas, with a particular focus on high-value assets, particularly in peer-to-peer conflicts. These long-range GBAD systems can, in turn, be supported by medium range solutions, which bring increased mobility and coverage into play. Through the use of quality short-range solutions, armed forces can provide high levels of coverage to assets on the move and overcome issues such as radar shadow.
Our RBS 70 NG solution brings together a range of features to enable high-quality short-range air defence. Missiles fired by the system are capable of achieving Mach 2 and the solution is effective at altitudes of up to 5000 metres. Reloading time once a missile has destroyed its target is less than five seconds.
The RBS 70 NG comes with a range of features aimed at enhancing the operator experience. Integrated, high-resolution thermal imaging allow for night and day capabilities, while advanced cueing allows for improved reaction times and target acquisition. An auto-tracker assists the operator during engagement and increases hit probability. Meanwhile, built-in video recording allows after-action review.
The overall lesson is clear. The secret to effective air defence today lies in combining the strengths of a number of systems. Armed forces looking for the best results should combine long, medium, and short range GBAD systems, include a wide diversity of guidance technologies, and make sure the RBS 70 NG is part of the mix.
Our GBAD solutions
With 24/7 all-target capability, RBS 70 NG is highly accurate, reliable, flexible and ready for any combat challenge.
Air threats are ever-evolving. Our MSHORAD Solution provides a highly mobile and formidable anti-air capability to effectively identify,deter, or neutralize airborne threats.