Naval Analyses: Roussen class fast attack craft of the Hellenic Navy

Written by D-Mitch

FACM of Roussen class in service with Hellenic Navy.
Photo: Hellenic Navy

The purchase agreement of the first three fast attack craft (FACs) of the Roussen class (Ρουσσέν) was signed in January 2000, and the construction took place at Eleusis Shipyards, while the Vosper Thornycroft (now BAE Systems Maritime) provided the necessary planning, logistics and equipment for the vessels. In August 2003 a contract was awarded for further two ships, Grigoropoulos and Ritsos, to be built by Elefsis. Ritsos was launched in October 2006 while the vessel was commissioned recently in 2015. A contract from the Hellenic Navy (Πολεμικό Ναυτικό) for an additional two vessels, to bring the total to seven, was placed in September 2008. The design is based on the smaller class of vessels of the Vita type serving in the Navy of Qatar and that’s why the class is named also Super Vita. The hull is made of steel while the superstructure is made of aluminum while the whole design has incorporated features for reduction of radar cross section. The first ship of the class was launched in November 2002 while three more vessels were launched the next three years. The sixth boat of the class has been reported to be named Karathanasis and it is expected to be delivered in 2017-18 while the seventh boat, Vlahakos, approximately that period as well. The class is named after its lead ship in honor of Second Mate Nikolaos Roussen, a distinguished World War II submarine officer. Roussen fought bravely during the war but he found death in April 1944 after being mortally wounded during a naval mutiny while he was leading a naval detachment to recapture corvette Apostolis.

Modified photo of a Roussen class FACM with MM40 Exocet bl.II. For a high resolution image click here.

The vessels of this class have impressive firepower and active defense for their small size and they are the newest vessels entering in service in Hellenic Navy (HN) incorporating many technological innovations that allow increased capabilities compared to the older classes. The design incorporates stealth technology to minimize radar, infrared, acoustic and magnetic signatures to reduce the chance of detection. The Roussens are the largest and heaviest FACs of HN having a length of about 62 meters and a maximum displacement of 720 tonnes. The top speed exceeds the 34 knots while the vessel has a maximum range of 2,250 nautical miles at 18 knots. The crew consists of 45 people. Each boat carries also one Rigid-Hulled Inflatable Boat (RHIB).

The Fast Attack Craft's design incorporates advanced stealth technology to minimise infra-red, radar, magnetic and noise signatures to reduce the chances of detection and enhance operational effectiveness of the ship. - See more at: http://www.baesystems.com/product/BAES_020356#sthash.tVauwVBS.dpuf

OTO Melara 30mm guns. Photo: D-Mitch

OTO Melara 76mm of Krystallidis

The Roussen class boats have a fully automatic OTO Melara Super Rapido main gun of 76mm/62cal on the bow deck. The gun is capable to intercept air and surface targets at a distance of 4 km (at 85 degrees) and 16 km (effective 8 km) respectively unleashing 120 rounds per minute weighting greater than 6 kg each. In comparison with the basic Compatto of the same manufacturer which is the main gun of the rest of the main surface combattants of Hellenic Navy, Super Rapido has an increased rate of 35 rounds per minute. The Roussens have also two OTO Melara Single naval mountings having a stabilized single 30mm Mauser Mod F Mk30 dual-feed cannon, with160 rounds of ammunition being carried for ready use.

OTO Melara 30mm gun (starboard)
Photo: D-Mitch

The cannons are manufactured locally by EAS (Hellenic Defense Systems). These naval mountings are automatic, with local or remote control but they require an operator in a cabin to start their engines, for safety reasons etc. The system is gyro-stabilized and joystick controlled (the operator always retain priority on target engagement) using the data from the sensors on board of the ship. The guns have a high cyclic rate of fire of 800 rounds per minute and can engage air and surface targets at up to 3.000m.

Modified photo of a Roussen class FACM with MM40 Exocet bl.IIΙ. For a high resolution image click here.

MM40 Exocet Block II of Daniolos.
Photo: D-Mitch

MM40 Exocet Block III of Ritsos.
Photo: D-Mitch

However, the most significant armament of the class is eight (8) MBDA MM-40 Exocet Block II/III guided anti-ship missiles with a range of 72 km for Block II and more than 180 km (!) for block III. The Exocet missiles have a warhead of 164 kg. Block III Exocet is lighter than the previous block but has an increased range due to the use of a turbojet engine and the four air intakes that provide a continuous airflow to the power plant during high-G manoeuvers. Block II equips only the first three vessels while the rest of the vessels are equipped with the Block III. The missiles of the 3rd vessel will be replaced as well with the newer block in the near future. The guided missiles of the newest block are the long arm of HN as they exceed in range and kinematic performance all the other missile systems in the service of HN vessels including Harpoon missiles that exceed slightly the 120 km range. The Block III accepts also GPS guidance system waypoint commands which allow it to attack naval targets under different angles and to strike land targets giving a clear advantage to the naval user in the Aegean. The missile guidance is inertial in mid-flight until turns on active radar late in its flight (active guidance) to the corresponding trigger point for the detection and locking of its target. In order to minimize the recognition from rival radar and infrared seekers and the subsequent attack of the projectile from the air defense around the target, the system maintains a very low altitude during ingress, staying 1–2 m above the sea surface (sea-skimming) while the speed is high approaching 0.9 Mach. Due to the effect of the radar horizon, this means that the target may not detect an incoming attack until the missile is only 6,000m from impact and thus it leaves little time for reaction of the target’s CIWS. We should add also that the missile has low signature and it has enhanced target discrimination and ECCM making it very difficult to be intercepted.

According to latest news (May 24, 2016), the MM40 Block II Exocet missiles will be removed from the first three Roussens in order to equip the four upgraded Laskos class FACM (currently carry the old MM38 SSM), while the three Roussens will be equipped with the latest Block III missiles similarly to their younger sisters, Grigoropoulos and Ritsos.

RHIB of Roussen. Photo: D-Mitch

RHIB of Daniolos. Photo: D-Mitch

RAM Mk 31 GMWS. Photo: D-Mitch

RAM Mk 31 GMWS.
Photo: D-Mitch

For specialized antiaircraft and antimissile defense (CIWS) other than the guns, the vessels have the Mk49 Guided Missile Launching System (GMLS) with 21 missiles ready to launch RIM-116 Rolling Airframe Missile (RAM) (Block 1A). Together, missiles and launching system comprise the RAM Mk 31 Guided Missile Weapon System (GMWS). RAM is a class-leading weapon system providing a full perimeter protection to the vessel operator. It allows naval vessels to effectively engage high-performance, supersonic and subsonic threats, including sea-skimming, anti-ship missiles, high-speed incoming vessels, rotary and fixed-wing aircraft, helicopters and other surface targets. The Block 1A missile has infrared guidance system that enables it to intercept missiles that are not emitting any radar signals while the Block 0 passive radar homing capabilities have been retained. The range exceeds the 9 km and the speed surpasses the 2 Mach. All the launchers on the Roussens, have been upgraded το Μod 3 in order to launch the newest RAM Block2, an upgraded version of the RAM Block 1 missile aimed at more effectively countering more maneuverable anti-ship missiles. A larger, more powerful rocket motor and advanced control section make the missile two and a half times more maneuverable with one and a half times the effective intercept range. An enhanced RF receiver allows detection of anti-ship missiles that employ low probability of intercept receivers.

MG3 of Roussen class FACM

TDS, MG3 and SRBOC

The armament completes two light machine guns Rheinmetall MG3 of 7,62mm. The rate of fire is 1,000-1,300 rounds per minute and the effective firing range is close to 1km.

View of Ritsos. Photo: D-Mitch

Mainmast of Daniolos. Photo: D-Mitch

Stern of Ritsos. Photo: D-Mitch

Thales MW08 radar of Ritsos.

Roussens are equipped with cutting edge electronic systems with the majority of them manufactured by Thales Group. You can have an overview of the systems here. The following information is based on the documents that are provided online by the manufacturer company. The vessels have the MW08 of Thales (formerly Signaal), an all-weather G-band (C-band) 3-D short to medium-range surveillance and target acquisition radar. The multi-beam concept of the MW08 provides a near-hemispherical coverage in one scan without the need for search patterns in the elevation domain. It enables very rapid target acquisition and tracking by weapon control systems, by providing target range, elevation, bearing and velocity data for each threat on every radar scan. All system functions, including target detection, air track initiation, target tracking and built-in test equipment, are automatic. Surface track initiation can be performed automatically or manually. Multistripline antennas, with digital Fast Fourier Transform (FFT) beamformer, Doppler FFT processing and tracking, minimise the effects of clutter and jamming. The MW08 is capable of tracking up to 160 air targets and 40 surface targets simultaneously. Track data, and (optional) IFF data, is transferred to the command and control system and, to the weapon deployment console for direct surface-to-target engagement. The system detects targets up to Mach 4 and maximum free-space, single-scan detection range, at 80% probability of detection 0.1 m2 in 17 km (source). The radar is designed to counter threats from aircraft and low flying antiship missiles. It can also deal with the high level missile threat.

Daniolos, Roussen class FACM at Bosporus. Photo: Alper Böler

Two Roussen class FACM lead a large flotilla of FACM and patrol boats.
Photo: Hellenic Navy

From left to right: MIRADOR, DR3000, MW08, SCOUT, STING
Photo: D-Mitch

Roussens have also the SCOUT Mk2 Thales Naval Nederland, a Low Probability of Intercept (LPI) short-to-medium range surface surveillance and tactical navigation radar. Scout can be operated as a stand-alone mobile system for flexible responsiveness. Additionally, the system can be operated remotely (radio or line connection). It is an all-weather fully solid-state system of high reliability operating in X-band radar feauturing Frequency Modulation Continuous Wave (FMCW) and therefore has an extremely low output power which makes the system ideal for cover operations in hostile environments where radar silence is required and thus its transmissions cannot be detected by ESM systems or radar warning receivers. SCOUT Mk2 outstandingly detects targets in adverse sea clutter conditions, thanks to its very small range cell size. The system is also very suitable for coastal surveillance. The range of the radar exceeds the 44km. In the same antenna is is integrated also a BridgeMaster E navigation radar of Decca.

The mainmast of Daniolos. Photo: D-Mitch

Thales STING-EO Mk2. Photo: D-Mitch

Roussens are equipped also with the STING-EO Mk2 of Thales, a highly capable, medium range, lightweight, dual band (I and K) weapon control system, primarily for gun control. The system offers support functions such as sector search (with automatic target detection), missile launch detection, projectile position measuring during gun fire and kill assessment support, it supports gun fire control, it performs kill assessment and makes a valuable contribution to classification and identification of threats. In addition, the system can be used as a surveillance sensor, even under radar silence conditions. STING-EO Mk2 combines a 1.2 m radar director with a full set of electro-optic equipment (TV/IR/laser), including optronic tracking and an automatic ‘best sensor’ selection process. The three data sources (I, K and EO) provide high redundancy, high performance and ECCM resistance. A shell-measuring feature is incorporated to support facilities such as Pre-Action Calibration (PAC) and Miss Distance Indication (MDI). The fully solid state STING-EO Mk2 provides the best weapon control for medium-sized vessels.

Hard-kill and soft-kill weapon systems of a Roussen class fast attack missile craft. High resolution image here.

Thales MIRADOR

DR3000 ESM and MIRADOR

Another weapon control system that the class features it is the MIRADOR, a compact, fully optronic observation and weapon control system. The one-piece stealthy sensor head houses a mix of electro- optical sensors for TV surveillance, TV tracking, IR tracking and laser range finding. Its lightweight design enables ultra-quick responses. An ergonomically designed state-of-the-art Human Machine Interface completes the system in a stand-alone configuration. MIRADOR acts as a secondary passive fire control and observation channel on the class. As all the main vessels of Hellenic Navy, Roussens are equipped with the Electronic Support Measures (ESM) system DR3000SLW. The vessels also feature a datalink Link 11, integrated together with the other weapons, guns, radars, sensors, EW system, chaff launchers and communications in the TACTICOS Combat Management System of the vessels (more information here).

P71 Ritsos, the latest boat in the Roussen class. Photo: D-Mitch

SRBOC decoy launcher behind a TDS

Mk137 SRBOC launcher

To deceive enemy missiles except ESM countermeasures, the class is also equipped with an ALEX Automated Launch of Expendables System by Lockheed Martin Sippican's Passive Decoy Systems Group which is linked to the ESM wind and navigation sensors. ALEX continuously provides all the necessary information to the operator, automatically (or semi-automatically) selects the best tactic for optimum decoy deployment and, if desired, automatically (or semi-automatically) implements the tactic. ALEX may be operated in an automatic or a semi- automatic mode. Manual override is available at all times, regardless of the operating mode selected. The system on Roussen class consists of a pair of deck mounted 130mm SRBOC decoy launchers. The ALEX System provides shipboard management of expendable decoy cartridges via a computer controlled countermeasure system used with deck-mounted launchers.

TDS. Photo: D-Mitch

Target Designation Sight (TDS)
on Daniolos. Photo: D-Mitch

TDS. Photo: D-Mitch

INMARSAT FLEET 77 of Roussen.
Photo: D-Mitch

SAILOR SATCOM

Each vessel is equipped with two Target Designation Sights (TDS) that provides means for optical investigation, target designation and weapon firing. The TDS is equipped with binoculars and the latest version includes a Laser Range Finder. Bearing and elevation data are fed into the CMS system but the TDS can also be used for emergency control of a gun or CIWS system. The importance of the function of the TDS is re-emphasised against asymmetric tactics such as piracy and insurgency. Notice also that Roussen and Krystallidis have a second radome behind RAM Mk31 system, an INMARSAT FLEET 77, due to the role they have these two vessels as leaders of FAC flotillas. For more photos of the class click here.

Roussen, leader of FAC flotilla. Notice the SATCOM (INMARSAT FLEET 77)
radome behind the RAM launcher. Photo: Andreas Michopoulos

Bibliography:

Naval Analyses

Wednesday, 11 June 2014

Roussen class fast attack craft of the Hellenic Navy

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