Tuesday, 1 July 2014

Aquitaine class (FREMM) frigates of the French Navy, Royal Moroccan Navy and Egyptian Navy

Written by D-Mitch

Frigate Aquitaine, FREMM. Photo: DCNS
Aquitaine class is the French variant of the FRigate European Multi-Mission (FREMM) class, a class of frigates designed by the French DCNS and the Italian Ficantieri in a joint program to replace the existing destroyers and frigates within the French and Italian navies. The frigates between the two navies share some general characteristics, weapons and systems but also have several differences in the equipment related to propulsion system, electronic equipment and weapons following the different requirements of both navies. Thus, the Italian Navy is building two variants, one for ASW (Anti-Submarine Warfare) role and one for GP (General Purpose) role. However the differences between these Italian variants are focused basically only in some of the main weapon systems and specifically in the guns and missiles. The GP versions are equipped with a 5in (127mm) gun on the bow deck while the ASW versions retain the 3in (76mm) gun and they are equipped also with four MILAS ASW missiles. Both the two Italian variants will be analyzed in another article. In contrast, the French Navy is acquiring only a multi-mission variant (for the moment) with advanced ASW capabilities as the vessels are equipped with towed sonar array and the capability for land attacks.

Modified photo of Aquitaine class frigate of the French Navy. Photo: DCNS. High resolution image here.

The initial plan of French Navy was to replace the seven (7) destroyers (not such classification in Marine Nationale) of  Georges Leygues class, the two (2) remaining destroyers of the Tourville class and the nine (9) corvettes of the D'Estienne d'Orves-class; 17 vessels in total. However, the number of the FREMMs under construction have been reduced dramatically due to the economic crisis. The plan was revised down to just 11 frigates in 2008 and thus replacing the fleet of destroyers but recently in 2013 the number of FREMM frigates to enter service with the French Navy was reduced to  just eight. In that way, French Navy either will decrease the fleet or they will need to increase the budget in order more FREMMs or another type of vessels to be built. A decision on whether or not to build the remaining 3 FREMM will be made in 2016. The D'Estienne d'Orves-class will possibly be replaced by a different type and not the expensive and high-tech FREMM. The first of the Aquitaine class entered in service in August of 2012. To date one export has been an ASW variant for the Royal Moroccan Navy which purchased its Mohammed VI frigate in 2014, a similar to the Aquitaine class without the VLS for the SCALP Naval cruise missiles and without jammers and Narwhal gun systems. Another very recent export, (June 23, 2015) has been (also) an ASW variant for the Egyptian Navy, the FREMM Tahya Misr (former D651 Normandie). Similarly with the Moroccan frigate, the Egyptian one is without the VLS for the SCALP Naval cruise missiles ,SATCOM and the Nettuno jammers however the ship is equipped with the two Narwhal gun systems.

Aquitaine class
Aquitaine class
Aquitaine class
NH90 NFH for ASW

The Aquitaine class is a class of stealth frigates capable for any kind of mission with the exception of the AAW task that requires the replacement of the Vertical Launch System (VLS). The general characteristics of the class is displacement of 6,000tons, length of 142m, beam of 20m, maximum speed of 28knots and range of 6,000n.m. with a cruising speed of 15knots. The ship has a crew of 108 persons while it can accommodate up to maximum 180. Each vessel can accommodate an NH90 ASW helicopter (Kaman SH-2G on Egyptian vessels) or an equivalent type while it carries two RHIBs for commando operations. As a typical configuration in any kind of vessels the frigate has one main gun on the bow deck which is the fully automatic OTO Melara Super Rapido gun of 76mm/62cal. The gun is capable to intercept air and surface targets at a distance of 16 km unleashing 120 rounds per minute weighting greater than 6kg each. The gun has excellent performance in any kind of role, such as air defence, anti surface, anti-missile and shore bombardment role.

Click to enlarge: modified photo of Aquitaine class frigate. Photo: DCNS. In high resolution here.
The VLS behind of the main naval mount consists of 32 cells in total (only on French vessels) and particularly 16 cells of Sylver A43 VLS for MBDA Aster 15 anti-aircraft/missile missiles for local and area defence (medium range) and 16 cells of Sylver A70 VLS for SCALP Naval cruise missiles (see the video for Sylver VLS). The Aster 15 is vertically launched and autonomously guided with a maximum range of greater than 30km and a speed of higher than Mach 3. The missile provides protection to the vessel against a full spectrum of air threats such as anti-shipping missile including sea-skimming and high diver missiles, supersonic and subsonic missiles, anti-radiation missiles UAV and aircrafts (watch video) with a very high single shot probability . ASTER’s terminal dart is a lightweight, highly manoeuvring and agile missile equipped with a high-performance active RF seeker with capability against stealthy targets. Thanks to the unique combination of aerodynamic control and direct thrust vector control called “PIF-PAF, the missile is capable of high g manoeuvres. Together, these features give ASTER an unmatched hit-to-kill capability. The system has an extremely quick reaction time with high rate of fire and it provides full coverage under any kind of weather. There are propositions for a FREMM frigate with increased anti-aircraft capabilities with the replacement of the Sylver A43 and A70 VLS with the A50 that contains the larger Aster 30 missiles that provide long range interception capability for area defence. Both Aster 15 and 30 missiles featuring the same terminal dart. The Aster 30 has a two-stage propulsion system achieving the incredible speed of Mach 4.5 and the range of 100-120km.

From the left to right: Aster 15, Aster 30 and SCALP Naval.
Aquitaine's VLS
Tahya Misr's VLS
As it was mentioned in the previous paragraph the armament includes 16 cells in two silos of Sylver A70 VLS for MBDA SCALP Naval cruise missiles (not the Moroccan and Egyptian vessels). The fire and forget missile is vertically launched and it provides an operational capability with long range metric precision strike against politically / military sensitive targets performing high survivability and it is deployable day/night under all environmental conditions. This stealthy missile carries a 500kg warhead and has a range greater than 1,000km in a speed of approximately Mach 0.8 (see video). The missile is guided by GPS and it flights very low following a path based on the terrain where the target is located in order to avoid to be intercepted or spotted. When the missile has approached the target, it climbs and then bunts into a dive and thus achieving better identification of the target and maximum penetration. D650 Aquitaine fired a cruise missile on May 19.This was the first time that a European surface ship fired a European cruise missile.

Loading a SCALP Naval on Aquitaine.Photo: DCNS
D650 Aquitaine firing a cruise missile on May 19. Photo:  MBDA
D650 Aquitaine firing a cruise missile on May 19. Photo:  MBDA

MM40 Exocet Block III SSM
Exocet launchers without the canisters
The rest of the armament consists of eight (8) MBDA MM-40 Exocet Block III guided anti-ship missiles with a range of more than 180 km carrying a warhead of 164 kg. The missile accepts also GPS guidance system waypoint commands which allow it to attack naval targets under different angles and to strike land targets as well. 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. The missile has low signature and it has enhanced target discrimination and ECCM making it very difficult to be intercepted.

Modified photo of Tahya Misr frigate of the Egyptian Navy. High resolution image here.

Nexter Narwhal 20mm RWS
Close-up photo of a Narwhal RWS
In the armament are included two Nexter Narwhal remotely-controlled weapon stations (RWS) with 20mm guns (not the Moroccan vessel) installed at the top of the helicopter hangar, on the port and starboard sides, for close-in defence against all kinds of asymmetric threats, including suicide fast boats, divers, aircrafts and UAVs. The gun's firing rate is up to 800rds/min.

Modified photo of Mohammed VI class frigate. Photo: Michel Floch. In high resolution here.

MU90 torpedoes and Calzoni AHS
Torpedo launchers of FREMM.
For ASW the vessels have two twin Eurotorp B515/3 launchers for torpedo MU90/Impact torpedoes with Calzoni AHS (Automatic Handling System). The ships carry in total 19 torpedoes. MU90 is a lightweight torpedo with a warhead of 32.7kg, a speed from 29 to maximum 50 knots (!), around 10km with maximum speed and 23km with minimum speed. The torpedo, is of fire-and-forget type and it has been designed to counter any type of nuclear or conventional submarine, acoustically coated, deep and fast-evasive, deploying active or passive anti-torpedo effectors while it has an extreme agility and maneuverability. In the main counter-counter measures are included stationary target detection capability, decoy classification and anti-jammer tactics. The torpedo equips also the NH90 helicopter for ASW operations.

In the following video, Xavier Vavasseur  (on behalf of is aboard the frigate Normandie, while the ship is conducting sea trials off Toulon naval base in Mediterranean sea. In this video you can see the majority of the equipment is described in this article and to enjoy the state of the art technology!

The ship uses electric and diesel propulsion (CODLOG - COmbined DieseL Or Gas). According to DCNS, the electric propulsion of the ship guarantees a reduced acoustic signature for anti-submarine operations as the electric motors are silent. The diesel generators are for the high speeds and rapid acceleration from cruising speed. The exhaust gases of the diesel generators are reduced while openings on the ship are masked achieving in that way a more reduced signature. The mission endurance for the ship is 45 days.

Frigate Aquitaine (D650), lead ship of the class.

SETIS combat management system.
Photo: Thales
The bridge of a FREMM
The combat system of the ships is the DCNS SETIS (Ship Enhanced Tactical information System), an integrated combat system for networked multi-mission operations. SETIS features advanced algorithms to detect, identify and react immediately to threats with the most appropriate weapon system. SETIS combines a large range of equipment, sensors and long-range weapons for detection, identification and engagements in extreme conditions such as multiple attacks. The Thales SIC21 is a Command and Control Information System. According to Thales, SIC21 is a mission management capability to support all types of naval operations. It increases interoperability & information security within operational Command & control in National, Joint & multinational environments. Sea and Land continuum with deployment on all naval platforms, whether equipped with a Combat Management System or not, and land-based command sites.

Artemis IRST. Photo: Thales
Artemis IRST on the mast.
Thales Artemis IRST (Infra Red Search and Track) system is based on a full stare sensor suite and advanced real time algorithms for automatic detection and tracking. Artemis is designed to provide full tactical situation awareness for simultaneous surface and air surveillance. Directly connected to the Combat Management System, the IRST is able to provide confirmed tracks at long range on threats such as anti-ship sea skimming missile, fighter or small craft, and to deliver images to the crew to improve situation awareness. Artemis uses three sensor units fixed on a mast or topside structure to achieve 360°surveillance coverage in azimuth, with each connected to a central processing unit by a fibre-optic link.

Frigate Aquitaine. Photo: Michel Floch
Herakles 3D multifunction radar
Photo: Thales
Thales Herakles is a rotating 3D multifunction radar (phased array) in the E/F-band (S-band) combining surveillance and fire control radar and thus performing all functions involved in the establishment of air and surface pictures. Herakles performs target detection and tracking, target classification, weapon assignment and deployment and missile uplink guidance. Herakles is optimized to detect and track multiple SSM, ARM, diving missiles, fighters and helicopters in littoral environments. Each ship is equipped with two Terma SCANTER 2001 navigation radars. One of the radar systems is utilized primarily for navigation and surveillance, whereas the other guides helicopters when landing on the frigates. The navigation equipment includes also the Sagem SIGMA 40, an inertial navigation system based on ring-laser-gyro technology. The system provides all the data crucial for navigation: heading, roll and pitch, angular velocities, position and heave, horizontal/vertical velocities and accelerations, etc.

Tahya Misr (former D651 Normandie). Photo:Michel Floch
FREMM Tahya Misr
FREMM Tahya Misr
Tahya Misr (former D651 Normandie). Photo:Michel Floch
FREMM Tahya Misr

Sagem VIGY MM electro-optical
fire control system. Photo: Sagem
The Sagem VIGY MM is an electro-optical fire control system equipped with an integrated ballistic computer, a gun fire control interface and a high-performance gyrostabilized platform that allows long- or short-range, high-precision shooting by day or night, including in very rough sea conditions with poor visibility. Thanks also to its passive equipment it can operate in radar silence. Used against sea or air targets during all types of self-defense operations, Vigy MM can engage any symmetric/asymmetric threat, including terrorist threats, with identification capability. Whether integrated in a Combat Management System or operated in standalone mode, it enables manual or automatic sector surveillance, automatic 2D/3D target tracking, aid to identification and processing of 3D target designation information.

Tahya Misr FREMM.
Photo: Hellenic Navy
Frigate Mohammed VI. Photo: Michel Floch
Tahya Misr FREMM

The elegant silhouette of frigate Mohammed VI

CAPTAS 4 / UMS 4249 Variable Depth Sonar
Image: Thales.
CAPTAS VDS in action
The ships are equipped with a Thales UMS 4110 CL low frequency active and passive Bow Mounted Sonar and a variable depth towed sonar. The hull mounted sonar covers a very large area providing ASW all-round surveillance as it can detect any kind of threat or object from a long range in any environmental condition. Similarly with the towed sonar has an excellent target positioning allowing to prosecute and engage distant submarines with organic weapons or airborne assets. It is manned by a single operator. The towed sonar array is the low frequency active and passive variable depth sonar CAPTAS 4 / UMS 4249. The sonar according to Thales is capable of very large detection (even very quiet submarines in deep and littoral waters) in every environmental condition and it is very accurate and reliable in target positioning allowing to prosecute and engage distant submarines with organic weapons or airborne assets, The sonar is deployed and recovered automatically (manned by a single operator!).

The RHIB of frigate Normandie in its hangar
Antenna of ALTESSE C-ESM
UHF antenna.
The communications include a variety of equipment. Thales ALTESSE is a high performance wideband for Communication ESM providing early warning and tactical situation awareness capabilities based on interception and direction finding of the radio communication signals in HF and V/UHF band, that can be easily integrated with Combat Management System. The TMR6200 are receiver-exciters that use digital signal processing technology to offer cost-effective and highly flexible radios for HF naval communications systems. They can be operated independently as a standalone radio via the control panel or within an integrated naval communications system offering voice, data, messaging and e-mail services. The Thales TUUM-6 Digital Under Water Communication System offering Long range Low Probably Intercept (LPI) data transmission, high data rate transmission and communication with divers. Other equipment includes Link 11, Link 16, satellite and commercial communications with Syracuse antennas (SURFSAT-L terminal),  the Thales TRN 4000 Fixed Frequency UHF Transceiver and the Thales PARTNER Communication Management System to cope with crew reduction and a friendly use of the communications.

Cutaway of FREMM frigate by DCNS
CONTRALTO torpedo decoy launcher, via
The countermeasures include the DCNS CONTRALTO-V Torpedo Countermeasures system for surface vessels. CONTRALTO®-V is composed of several subsystems for an optimized defense against torpedoes: the reaction system, which calculates & suggests optimized evasive manoeuvres and sets off the countermeasures, the deployment system (launcher) fitted to several types of launchers (mortar, pneumatic, rocket) and the CANTO®-V countermeasure. CANTO®-V is a broadband active acoustic countermeasure. It is designed to saturate the torpedo data processing system by emitting specific and smart acoustic signals covering the whole torpedo frequency band in both active and passive mode. Its mission consists in exhausting the threat by creating and constantly renewing hundreds of false targets on a 360-degree coverage area (5 sec deployment). This concept, called dilution/confusion, is the only one capable of defeating advanced torpedoes while consuming less munitions and it is efficient whatever the number of torpedoes or their types and doesn’t need to be deployed far from the threatened ship. Watch the following video to understand how the system operates.

Sagem NGDS multiple decoy launcher
Photo: Sagem
Each of the vessels is equipped with two Sagem NGDS (New-Generation Dagaie System) multiple decoy launchers to counter a variety of threats such as anti-ship missiles and torpedoes. NGDS is integrated in the ship's combat system's detection and warning system and can react automatically to current or emerging threats, in extremely short times. Each system is equipped with a single dual launcher including decoys (infrared, radar or acoustic) adapted to the threat to be neutralized. The NGDS system adapts to all types of munitions: electromagnetic or IR decoys, Active Offboard Decoy (AOD), Anti-Torpedo Decoy and/or laser jammer, deployed at short, medium or long range. The launchers are linked to a computer that selects the decoying best-suited technique. The Electronic Warfare Coordination Center provides the commanding officer with the ship’s tactical situation and coordinates the various Electronic Warfare (EW) tactics: threat evaluation, tactics optimization, coordination of decoys, radar jammer and more generally, electronic countermeasures Electronic Support Measures (ESM).

Frigate Provence with modifications, for stealth and interference purposes.
All the frigates of the class in French service will receive these modifications.
Original photo by Franois Guiganton

Electronica NETTUNO 4100 electronic jammer
Photo: Electtronica
The ECM equipment of the Aquitaine class is very advanced offering a range of high fidelity jamming techniques designed to counter long range search radars, target acquisition radars and missile radars operating in both their search and locked-on modes. It includes a Thales VIGILE ESM/ELINT system, a Thales TSB 3520 ATC & IFF Combined Interrogator Transponder and two SIGEN EW systems combining Thales ESM sensors and Electronica NETTUNO 4100 electronic jammers for active electronic defence. The NETTUNO-4100 can exploit a wide range of ECM techniques against surface search and tracking radars in support of anti- surface engagements. Some of the characteristics of these jammers (according to the company) include a very high performance, smart ECM modes, both noise and deception, exploiting DRFM-generated jamming signals, multi-threat jamming capability, electronic beam steering (electronically stabilized against ship movements), high level of readiness (no warm-up), full solid-state design ensuring high ERP and graceful degradation in case of failure and high reliability and maintainability. The frigate of Royal Moroccan Navy lacks these jammers.
Frigate Lanquedoc of the French Navy. Photo: Ewan Fotografik

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