The littoral operational environments envisaged by Australia are some of the most complex in the world. These tropical waters are laced with islands and reefs which make it difficult for vessels to navigate freely and conduct operations. The highly cluttered environment provides cover to friendly units and enemy vessels alike, necessitating the use of systems that are robust, nimble and intelligent. With its naval roots in the equally complex shallow waters of the Baltic archipelago, Saab is positioned as a world leader in products and solutions for the littoral environment.
As the nature of conflicts change, this and similar environments have become of greater strategic importance and brought Saab’s products into the forefront. Saab’s latest anti-ship missile, the RBS15 Mk3, is uniquely adapted to the challenging environment of the littorals; able to engage targets with precision, over long distances and in a cluttered battlespace.
A key capability of the RBS15 is the ability to be launched from a range of air, sea and land platforms which makes it an ideal solution to Australia’s requirements for a deployable land based anti-ship missile capability.
The Littoral – the toughest environment there is
The RBS15 Mk3 was designed for operation in the cluttered littoral environments of the Swedish archipelago. One of the many important features of the RBS15 is its ability to fly at sea-skimming altitude. The onboard altimeter continuously monitors the height above the waves and minimizes the missile’s flight altitude. Flying at a minimum altitude along the entire trajectory allows the missile to approach the target undetected, remaining below the radar horizon until the very last minute. Especially in a cluttered environment, where other potentially undetected enemy vessels may be hiding along the flight path, it becomes important to minimize the probability of detection by having a sea-skimming approach from launch to impact.
By reducing the visibility of the missile in the electromagnetic spectrum, the missile can get even closer to the target before detection. Though as naval ships employ radars with ever increasing fidelity and resolution, massive investments in reduced RCS and stealth features will fail to pay dividends. We’re already seeing this shift in the air theatre and the naval scenario is no different. Instead, managing the detection by avoiding hard-kill and soft-kill measures will become increasingly important. The RBS15 Mk3 penetrates enemy defenses by maintaining a sea-skimming profile and employing evasive maneuvers and advanced electronic counter-countermeasures (ECCM).
With today’s technology we can control many aspects of the battlefield. Unfortunately, the weather is still not one of them. Since a battle might take place at any time, in any weather and in any condition, missile systems cannot be dependent on fair weather. Over long distances, the weather may vary greatly so a missile designed for use in the littoral environment, like the RBS15 Mk3, needs to be insensitive to changing weather conditions. The missile’s target seeker needs to be capable enough to find its target even in adverse weather. For this reason, an active radar target seeker is necessary, as it is not negatively affected by the atmosphere or the water in it, like infra-red target seekers.
The need for autonomous weapons
The ability to deny the availability of GPS and data links within a conflict area is becoming easier and easier to obtain. Today, relatively unsophisticated adversaries can obtain and operate basic Electronic Warfare (EW) equipment that presents an operational threat to units relying on GPS and data-links. Some countries have already launched programs aimed at finding technologies that can supplement GPS for that very reason. Against a sophisticated adversary, weapons will need to be able to operate autonomously and be insensitive to powerful EW that disables or disrupts communication channels. Another reason to use an active radar target seeker is the size of the target seeker area. Since the radar is not dampened by atmospheric water, its range is much greater than for example, an IR sensor. This allows for detection and acquisition of targets moving at high speed at long ranges, without requiring target position updates via a data link or relying on GPS positioning.
Approaching and finding a target is just the first step, penetrating its defenses is where things get difficult. Thankfully, the RBS15 Mk3 is well equipped with measures to counter both soft-kill and hard-kill defensive systems that may be employed by the target.
The missile’s active radar target seeker features a high power monopulse with frequency agility and a jittered Pulse-Repetition Frequency (PRF). These and other features allow it to counter all existing forms of active and passive electronic countermeasures. In the unlikely event that the target seeker becomes jammed, RBS15 Mk3 has a Home-On-Jam feature that effectively turns it into an anti-radiation missile. This places the adversary in a difficult position; forced to either stop jamming and see the missile find its target, or continue jamming and become the target.
The target seeker also has a unique target discrimination capability thanks to the high resolution in both bearing and range which also contributes to insensitivity to chaff, decoys and jammers. Additionally, the target seeker’s behavior is software controlled. This allows the RBS15 to easily adapt to new threats as they emerge and for new features to be added through software updates.
The RBS15 Mk3 penetrates the final layers of defense by making itself difficult to detect and difficult to shoot down. A reduced signature together with a silent approach from below the target’s radar horizon delays detection until the very last moment. Flying low also reduces the effectiveness of the tracking sensors and the proximity sensors of the munitions fired against the incoming missile. Even if the target’s defenses are capable and effective, they can be saturated by firing multiple missiles preprogrammed with a simultaneous time on target. The RBS15 Mk3’s superb navigational systems allow multiple missiles to arrive at the target at the same time, even when fired from multiple platforms and with different trajectories and approach angles.
Multiple 3D waypoints for utilisation of the missile´s potential
To be a reliable and effective weapon in a littoral environment a missile like the RBS15 Mk3 must be very maneuverable. Thankfully the RBS15 Mk3 is designed to operate in these waters and features great maneuverability and a flexible trajectory with multiple 3D waypoints that allows the operator to utilize the missile’s full potential. From over 200 km away the missile can quickly and easily be programmed to fly above or around the many islands in the littoral waters and to approach the target from any direction.
The next generation is coming
Saab has already been contracted by the Swedish government to develop the next generation of the RBS15. The updated missile system will have an improved combat range, an upgraded target seeker, and a lower mass compared to the earlier system. It will also have the ability to combat a wider spectrum of naval and land-based targets, an enhanced all-weather capability and a new modular design enabling future growth potential.
In the cramped and cluttered waters of the littoral, the threat of attack from the world-leading RBS15 presents a clear and present danger to any would-be aggressor both now and into the future.
Mandy Barlow, communications manager at Pacific 2017
+61 (0) 430 775 004
Saab serves the global market with world-leading products, services and solutions within military defence and civil security. Saab has operations and employees on all continents around the world. Through innovative, collaborative and pragmatic thinking, Saab develops, adopts and improves new technology to meet customers’ changing needs. Saab Australia develops advanced defence, security and civil aviation systems for domestic and international markets. Saab Australia is Australia's leading capability integrator now celebrating thirty years’ experience across a wide range of defence and civil projects