Close-In Weapons Systems are effectively the ‘last line of defence’ for naval vessels. CIWS have evolved in recent years as the immediate threats to ships have grown more complex, with new avenues of development in the area for companies and navies alike.
These weapons are perhaps best known for providing protection against Anti-Ship Missiles (AShMs) and are usually based on a gun in the 20mm to 35mm range. However, there is considerable variety among CIWS, both in terms of the systems themselves and the threats they counter, and the line between them and some other gun systems can easily become blurred. For the US and its NATO (North Atlantic Treaty Organisation) allies, one of the best-known CIWS systems is Raytheon’s Phalanx family. The Phalanx design has been in service since the 1980s, and is based around a 20mm radar-guided Gatling gun; with the latest iteration of the system known as the Phalanx Block-1B Baseline-2. The US Navy is currently upgrading all its Phalanx systems to this new baseline, with the project set for completion at some point in 2019, said Rick McDonnell, director of close-in defence solutions at Raytheon’s missile systems subsidiary. The major change in the latest upgrade has been a series of performance enhancements to the gun’s radar system, he said. This has worked on a number of levels, including upgrades to the radar signal processing architecture, Mr. McDonnell explained, though he could not go into further detail.
The focus for the US Navy over the past decade, aside from major upgrades such as improvements to the radar, has been on boosting the reliability of the system, Mr. McDonnell added, with a variety of subsystems being improved to meet this goal. In addition, there have been changes to the way in which Phalanx systems are upgraded or maintained, he said, with efforts to “improve or enhance the way in which systems are maintained or the way they are repaired,” either at pier side or in a land-based facility. The Phalanx design also forms the basis for other weapon systems, which have come into greater demand as the AShM threat has evolved. For example, Raytheon has also been working on installing its RIM-116 Rolling Airframe Missile family passive radar homing and infrared guided surface-to-air missiles on a range of US ships, said Matt Button, Raytheon’s programme director for the system. The SeaRAM is a version of the Phalanx design in which an eleven-round RIM-116 missile launcher replaces the gun. It has been installed on US Navy ‘Arleigh Burke’ class destroyers, including the USS Donald Cook, USS Porter, USS Carney and USS Ross, where it now operates in tandem with one Phalanx system: “Effectively you’ve added another layer of defence to those ships because they did not previously have the RAM missile,” Mr. Button said: “That gives you a little bit more time to deal with some of these challenging threats.” SeaRAM is also integrated on the Us Navy’s ‘Independence’ class Littoral Combat Ships (LCSs) and will soon be integrated upon the ‘Freedom’ class LCS variant.
The RAM missile offers more range than the Phalanx and has “a very good amount of manoeuvrability to deal with challenging threats that have a high amount of manoeuvrability and a high degree of speed,” Mr. Button observed. Moreover, the SeaRAM’s range provides a ‘fire-and-forget’, Mr. Button added, to deal with one or more incoming threats. Regarding the conventional Phalanx gun-based system, “you have to stay on that threat until you can confirm that you have destroyed it,” he said: “The SeaRAM gives you the opportunity to use that fire and forget capability.”
Another well-known CIWS in the Western world is Thales’ Goalkeeper; a 30mm system originally developed by Signaal. While it is most associated with the Koninklijke Marine (Royal Netherlands Navy), Goalkeeper has a range of international users, such as Portugal and the Republic of Korea (ROK). The last Goalkeeper for the Netherlands rolled off the production line in the 1990s, while the most recent delivery was made to the ROK Navy in 2006. Thales has a “running contract” to upgrade the system for the Dutch and Belgian navies, said René de Jongh, Thales’ strategy and marketing director. It also offers the same upgrade package to its international customers through the Goalkeeper Service Life Extension Programme, and the ROK Navy is likely to sign a deal to this effect in the near future, according to Mr. De Jongh.
The range of threats against ships has expanded in recent years. The attack on the USS Cole ‘Arleigh Burke’ class destroyer by Al Qaeda insurgents in the port of Aden in October 2000, which killed 17 crew and injured 39, highlighted a need to defend ships against surface threats. For example, the Phalanx was upgraded to address these concerns as well as threats from slow-moving aerial targets. These kinds of dangers have only increased in recent years, observed Mr. De Jongh: “I think that for the majority of customers, a real close-in weapon system was not their highest priority until recently … But I think people have become more aware that these kinds of threats are there.” This has become more pronounced due to the increased threat posed by non-state actors, Mr. De Jongh added: “A state actor attacking a ship is very visible, but it is very difficult to do something against a non-state actor,’ he said. “The only option is to defend yourself.” Mr. McDonnell, meanwhile, pointed to attacks on ships in the port of Aden, where rebels have used relatively unsophisticated weapons against surface combatants: “There’s a proliferation of unsophisticated systems that non-nation states are willing to use against capital ships, which the ships have to defend themselves against,” he said adding that because these types of weapons are relatively cheap and unsophisticated, adversaries could potentially use them in great volume, though such an attack has not yet occurred: “The existing systems are able to deal with this … but it is something to keep an eye on. We need to ask whether there are things we can do that can make our systems even more effective?”
While there is a natural concern over the threats from non-state actors, Mr. McDonnell pointed out that the more traditional threats from nation states are also developing rapidly, with AShMs becoming faster and more manoeuvrable. Eric Wertheim, a naval expert and author of the US Naval Institute’s Combat Fleets of the World, echoed this point, saying that missiles are becoming much faster, stealthier and more manoeuvrable. The aim for missile developers is “to fly past the operational capabilities of the CIWS,” he noted: “It’s constantly a game of catch-up by each side: as the defensive side gets better, the offensive side has to adapt, and once the offensive side adapts it is up to the defensive side to be able to answer that threat,” he said.
The threat from Unmanned Aerial Vehicles (UAVs) has also grown more pronounced, with the systems posing significant challenges for vessels: “UAVs are becoming more ubiquitous, and they’re a threat in a lot of different aspects,” remarked Charlie McCullough, director of maritime business development at BAE Systems: ‘They can carry munitions, and most can be guided to the exact spot on a ship that the operator wants them to go.” While BAE Systems does not produce a classic CIWS system in the sense of targeting AShMs, the company makes a range of weapons that defend ships against such growing challenges as surface vessels and UAVs, notably the firm’s Mk.38 Mod.3 naval gun, Mr. McCullough added. In addition, the company is leading the development of the US Navy’s Office of Naval Research (ONR) electromagnetic (EM) rail gun; a technology that uses high-power electromagnetic energy instead of explosive chemical propellants to launch projectiles faster and further than other systems: Such technology could have significant applications in the CIWS space, Mr. McCullough observed: “I would see an electromagnetic launched system being something that would be relevant to the CIWS threat set, but also (longer-range threats) as well,” he said.
Directed energy systems are another emerging area with potential uses in CIWS, perhaps most notably through the US Navy’s AN/SEQ-3 Laser Weapon System (LAWS), which has been tested on the USS Ponce ‘Austin’ class amphibious support ship, using the Phalanx’s radar and fire control systems. Rheinmetall, producer of the 35mm Rheinmetall/Oerlikon Millennium Gun, is also looking into the potential of such technology. Rheinmetall has conducted trials in which the Millennium Gun’s cannon is replaced with lasers, and has worked with the German Navy on developing a High-Energy Laser (HEL) effector. Mr. Wertheim said directed energy systems are the ‘Holy Grail’ of the CIWS domain: “That technology is by far the biggest game changer, because you do not need to be concerned about magazine capacity,” he explained: “When you’re talking about CIWS, very often they have limited magazine capacity, and it’s very expensive to launch defensive missiles. Directed energy alleviates a lot of that.” One of the major advantages of directed energy is the possibility of a theoretically almost unlimited magazine depth, he said. “Right now potential adversaries can build offensive missiles cheaper than we build defensive missiles, so in theory it’s only a matter of time before you get overwhelmed, and you have to leave the battle to re-arm,” Mr. Wertheim noted. “Once you get to directed energy, once you get to something that’s more affordable, then you even the equation out.”
BAE Systems has installed a directed-energy weapon as an adjunct to the Mk 38, Mr. McCullough said. He emphasised the benefits of using both a laser and a more traditional gun: “You still have the optics and the situational awareness that the gun brings to the ship, but now you have the laser piece; that really helps with the saturation problem, because when you fire a laser you still have the same amount of ammunition in your magazine. That’s the beauty of lasers.” Such systems could in theory eventually replace Phalanx, Goalkeeper and similar guns, Mr. Wertheim said, but this would be a long process, while smaller ships are likely to continue to use guns as they would not have the power generation capacity to support directed energy weapons: “The larger systems might eventually transition to directed energy,” he said, “but guns still have a very important place, especially on smaller vessels that are not able to handle the power for directed energy.”
It will take time to work out how laser systems will ultimately be built into the surface fleet, argued Mr. McDonnell. He pointed to a new US Navy effort, the High Energy Laser With Integrated Optical-Dazzler and Surveillance (HELIOS) project. The navy is currently soliciting proposals for HELIOS, with Raytheon as one of the bidders. “This programme will be the proof in the pudding for directed energy,” Mr. McDonnell said. “this is intended to be something that’s much more representative of what you might actually have in operation.’
However, Phalanx is set to remain in operation for decades to come, Mr. McDonnell said, with any laser system likely to work alongside it, rather than replacing it. Looking forward, Raytheon and the US Navy has been laying the groundwork for a technology refresh of Phalanx, including modernisation of the Gatling gun, replacing the pneumatic drive systems with electronic equivalents. This would boost the reliability of the system, he said: “We did some demonstration work last year and are now working with the US Navy on requirements for an electric gun, which replaces all the drive systems for that Gatling gun with an electronic motor and electronic controls.” Mr. McDonnell added. The overall goal is to ready the system for the challenges of an ever-evolving threat: “We want to give the user flexibility to adapt the way the gun is being used to whatever particular situation they find themselves in.”