Translate in your language!

Friday 7 November 2014

Karel Doorman (M) class frigates of the Portuguese Navy, Chilean Navy, Royal Netherlands Navy and Belgian Navy

Written by D-Mitch

Modernized frigate Van Spejik
Photo: Willem Harlaar
Frigate Bartolomeu_Dias
Photo: Jimmy C. Pan, US Navy
The Karel Doorman class is a class of eight (8) frigates built by Damen Schelde Naval Shipbuilding, the former Royal Schelde Dockyard, for the Royal Netherlands Navy (Koninklijke Marine) and they were commissioned in the period 1991-1995.  International interest in the M-frigates as well as changes in the Royal Netherlands Navy prompted the sale of two frigates each to Chile, Belgium and Portugal. Therefore, in 2004, Tjerk Hiddes and Abraham van der Hulst were sold to Chilean Navy (Armada de Chile) and renamed Almirante Riveros and Blanco Encalada respectively. In 2005, Karel Doorman and Willem van der Zaan were sold to Belgian Navy - Belgian Naval Component (Dutch: Marinecomponent, French: Composante marine, German: Marinekomponente) and renamed Leopold I and Louise-Marie respectively. The next year, Portuguese Navy (Marinha Portuguesa) purchased two vessels of the class, Van Nes and Van Galen which renamed Bartolomeu Dias and Francisco de Almeida respectively. The Dutch together with the Belgians decided to upgrade their frigates by rebuilding both hangar and helicopter deck to accommodate the NH-90 helicopter as well as to replace the forward mast for fitting a new phased array surface search radar and an electro-optical surveillance system. The Dutch and Belgian frigates followed also an extensive overhaul and Service Life Extension Programs (SLEP) to their equipment. These will be referred as the Karel Doorman Mod. (modernized) frigates to be distinguished from the non-modernized ones. Note that in 2018 the Portuguese Navy decided to modernize its two Karel Doorman class frigates (Mid-life update), the first frigate started modernization in 2018 and being completed by 2020, the second frigate will start modernizing in 2020 and will be completed by 2022.

Modified photo of a Chilean Karel Doorman (M) class frigate. For high resolution image click here.

Dutch frigate Van Speijk (F828)
The general characteristics of the class is a displacement of 3,320tons, speed of 29-30 knots, length of 122,3m and a range of 5,000n.m. with the speed of 18 knots. The complement is 160-170 people. Each ships carries two Rigid Hull Inflatable Boats (RHIB) at each side of the funnel. The Chilean frigates carry a Eurocopter AS532 Cougar helicopter and the Portuguese a Westland Super Lynx. As it is has been already mentioned in the introduction, the Dutch and the Belgian frigates, after their modernization, carry an NH90 helicopter. According to the shipbuilder, the design of these frigates  reduces the radar, under water noise, infra-red and magnetic signatures. The hull design is based on extensive research into seakeeping and propulsion, giving high sustained speed in seaway and a wide weather window for helicopter operation. Due to the highly automation in machinery control and C³I systems the class has a characteristically low manning level.

Modified photo of a Portuguese Karel Doorman (M) class frigate. For high resolution image click here.
Machine guns on Van Amstel.
Photo: D-Mitch
The 3in gun of Van Amstel.
Photo: D-Mitch
As a typical configuration of the majority of European major surface combatants, the ships are armed with the standard OTO Melara Compatto 3in (76.2mm) fully automatic gun installed forward of the bridge. This gun can hit air and surface targets at a distance of 4 km (at 85 degrees) and 16 km (effective 8 km) respectively with a rate of fire 85 rounds per minute and weight of shell greater than 6 kg. Except the main naval gun, the ships are equipped with a combination of heavy machine guns (M2HB of 12.7mm) or light machine guns (FN MAG of 7.62mm). The M2HB (Heavy Barrel) has a maximum (effective) range of around 1,830m and a cyclical rate of fire of about 500-600 rounds per minute. The FN MAG has a maximum (effective) range of about 1,800m and a cyclical rate of fire of approximately 750-950 rounds per minute.

Modified photo of a Belgian modernized Karel Doorman (M) class frigate. For high resolution image click here.

Harpoon launchers on board frigate
Van Amstel. Photo: D-Mitch
The usual load of surface-to-surface missiles (SSMs) of the ships is four (4) to eight (8) Boeing RGM-84C Harpoon anti-ship missiles in two Mk141 quad launchers amidships. These missiles have a range greater than 120km, a sub-sonic of speed of 860km/h (Mach 0.9) while they carry a warhead of 221kg. Harpoon missile has a low-level, sea-skimming cruise trajectory, active radar guidance and it is capable to perform pop-up manoeuver which it is a rapid climb of the missile to about 1,800m before diving on the locked target.

Modified photo of a Dutch modernized Karel Doorman (M) class frigate. For high resolution image click here.
The Mk48 VLS is clear at the port
side next to helicopter hangar on
 the Chilean frigate Almirante Blanco
Encalada. Photo: Katsuhiko Tokunaga
NSSM launch from Mk48 VLS
The anti-aircraft protection (and secondary the anti-missile) of the ships is based on a Raytheon 16 cell Mk48 Mod 1 Guided Missile Vertical Launching System (GMVLS) for RIM-7P NATO Sea Sparrow Surface to Air Missiles (SAMs) known as NSSM (NATO Sea Sparrow Missile). Originally developed as an air-to-air missile by Sperry and the U.S. Navy, the later versions were developed and produced by Raytheon and General Dynamics. Sea Sparrow is a short/medium-range, all-weather, all-aspect, semi-active guided missile designed primarily for the ship self defense role. The guidance system of the -M- variant allows mid-course upgrades and the ability to accept delayed lock-on. Sea Sparrow, is used for shipboard point defense on more than 150 ships of various classes for the U.S. and numerous other countries. The RIM-7P is the most recent model of the Sparrow family of missile systems, which began initial deployment in 1956 and has become the standard upon which many worldwide systems are based. The 7P model features performance improvements executing a variety of maneuvers in heavy clutter environments and much lower altitude air and surface target capability. Additionally, it is more time immune to the ever challenging countermeasures threat. The speed is close to Mach 4 and the range greater than 25km.

Frigate Francisco de Almeida of Portuguese Navy

Goalkeeper CIWS.
Photo: D-Mitch
There is provision for a second CIWS
forward of the bridge

The anti-missile protection is provided by a Close In Weapons System (CIWS), the Thales Goalkeeper. According to Thales, Goalkeeper is an autonomous and completely automatic weapon system for short-range defence of ships against highly manoeuvrable missiles, aircraft and fast manoeuvring surface vessels. The system automatically performs the entire process from surveillance and detection to destruction, including selection of the next priority target. However, manual override is possible at any stage in the sequence. Goalkeeper incorporates the 30 mm, 7-barrel GAU-8/A Gatling gun with special missile-piercing discarding-sabot (MPDS) ammunition, operating on the kinetic energy principle. The combination of MPDS ammunition and a firing rate of 4200 rds/min (!) gives the system the power necessary to destroy missile warheads. A high detection probability for small targets is ensured in all weather conditions by the use of a high-power, I-band search radar. Pin-point target tracking is achieved by the dual frequency I/K-band track radar. Continuous search with track-while-scan ensures rapid engagement of the next priority target in multi-target scenarios.
There is provision for a second Goalkeeper forward of the bridge. Watch some nice videos of the system's performance here and here.

System overview of Goalkeeper CIWS. Image: Thales
Mk46 Mod 5A torpedo
Photo: Daniel Barker, US Navy
Mk32 Mod 9 torpedo launcher.
Photo: D-Mitch
For Anti-Submarine Warfare (ASW) the ships are equipped with two twin Mk32 Mod 9 324mm torpedo launchers in fixed positions for Honeywell Mk46 Mod 5 active or passive/active acoustic homing lightweight torpedoes. These torpedoes have a range of about 8,500-11,000m at 45 knots (maximum speed) and they carry a very powerful warhead of 44.5kg for this category of lightweight torpedoes. They are designed to attack fast submarines and to engage them even over 400m below sea level as well as surface targets (latest variants such as Mod 5)

Mk32 Mod 9 torpedo launcher. Image:

LW08 radar. Photo: D-Mitch
The LW08 is a 2D radar system for long-range surveillance in D-band (L-band), providing target indication to weapon control systems. LW08 presents a clear picture of the environment; it does so, reliably, under any circumstances. LW08 performs with great frequency agility over a wide band, due to its synthesizer-driven TWT transmitter. Excellent performance under various clutter conditions is ensured by the wide dynamic range receiver with application of digital video processing, supported by circular polarization. The LW08 antenna has a low side-lobe level, which assists the system in operating under ECM conditions. The radar can detect a small missile from 100km or a fighter aircraft from 230km flying with Mach 4 while the tracking capacity is 400. Minimum range is 2km. The system on the Dutch and Belgian frigates has been upgraded to the latest level.

Frigate Van Amstel prior modernization. Photo: D-Mitch
SMART-S on the top of the main mast of Van
Amstel (prior modernization). Photo: D-Mitch
Thales SMART-S is the E/F-band (S-band) medium-to-long range 3D multi-beam acquisition radar for targeting of the ships. Smart-S is capable of automatic detection of targets (multi-target tracking capacity), followed by automatic track initiation and accurate tracking of these targets. It simultaneously deals with high-priority targets such as very small and fast low-flying or high-incoming antiship missiles and all other types of air and surface targets. Smart-S makes use of modern radar and signal processing techniques, such as a multiple-stripline receiving antenna, digital FFT beam forming, and FFT doppler processing, which drastically reduces susceptibility to clutter and jamming. Smart-S' 3-D capabilities are therefore virtually invulnerable to degradation from both natural environmental effects and intentional jamming. This provides an essential contribution to the threat evaluation process, especially in multiple-attack scenarios. It results in an accurate and timely target information exchange with the weapon control systems, enabling them to perform the fastest possible lock-on. The antenna system is bi-axially stabilized, using a lightweight hydraulically controlled platform, to enable a high mast position. Finally, the entire system has extensive automatic built-in test facilities and is easy to install and maintain. The system can detect a 0.1m2 target at 45km while for 2m2 target the range is increased to 90km and with speeds as high as Mach 3. The tracking capacity is 40 tracks for surface targets and 160 for air targets. The systems on the Dutch and Belgian frigates has been upgraded to the latest level.

Modified photo of a Dutch modernized Karel Doorman (M) class frigate. For high resolution image click here.

Launching RIM-7 SAM
Karel Doorman frigates have multi-weapon control systems for controlling both Sea Sparrow missiles and the 3in naval gun. Each vessel is equipped with two Thales STIR medium-to-long range tracking and illumination radars. Its design is optimized for stealth target detection in demanding littoral and ECM environments. The radar is a 1.8m Cassegrain monopulse tracker with an instrumental range of more than 60km. It comprises two STIR 1.8 and a central control panel with two STIR control consoles in CIC. EO sensors available are TV and IR for target observation and identification. The modernized ships in Belgian and Dutch service have received also an OIP MicroORBIS electro-optical sensor that provides excellent long-range day and night surveillance, reconnaissance and target acquisition capability with superior picture stabilisation in a full digital open architecture.

Almirante Blanco Encalada (FF-15) of the Chilean Navy
The main mast of Van Speijk
after her modernization.
Photo: Michael Nitz
Thales Sea Watcher component
The Dutch and Belgian frigates have been upgraded with the installation of a new integrated mast that includes alongside with the sensors described above, two new systems, the Thales Sea Watcher and the Gatekeeper. The Thales Sea Watcher 100 is a non-rotating active phased array I-band (or X-band) surface surveillance radar for asymmetric threat operations in the littoral, open-ocean and harbour environments with a typical operational range of up to 40 km. Sea Watcher 100 is a 2-D radar sensor designed to detect and track even the most difficult of surface targets, such as boats, periscopes, floating mines and swimmers which have a very small radar cross section, that are moving close to the speed of the waves and as such a near-zero Doppler value and that are down at the surface level, sometimes being hidden from view behind wave tops. Typical challenges that Sea Watcher 100 is designed to meet, include multi-path, surface duct propagation and shadowing effects, as well as backscatter and clutter from the sea surface. The non-rotating, staring nature of its antenna arrays allows it to spend more time looking at each possible target, which helps the processing to discriminate real targets from the clutter. Sea Watcher 100 operates using a single-mode concept, which frees the operator from having to select the best possible mode. The system automatically selects the optimum combination of waveforms to provide short-, medium- and long-range coverage, depending on the characteristics of the sea surface as seen from a certain distance. Sea Watcher 100's solid-state active phased array architecture with advanced beam steering and burst scheduling algorithms, ensures both high Doppler resolution and a high update rate, needed to discern small targets that are hidden in clutter. Short- and medium-range search is performed at two-second update rates, while for long-range search an update is provided every five seconds. The radar displays all ranges simultaneously so that the operator does not notice the mode changes and always has a total picture including all close-in, medium-range and long-range targets.

Thales Gatekeeper
The Thales Gatekeeper offers surround vision for close-in situational awareness up to a distance of 5-8 km, to as close as 15m from the ship, for safe navigation and against asymmetric tactics such as piracy, insurgency and swarm engagements. Gatekeeper is a 360°electro-optical surveillance suite comprising, non-cooled IR cameras and ultra high definition TV cameras (4 sensor units, each comprising non-cooled IR and three TV cameras with a combined view of 120° in azimuth) mounted in the mast, to provide a continuous un-blocked situational awareness for multiple operating positions. Its main role is to provide security through classification and identification of approaching objects, and target indication to remote controlled small arms. In addition, the system will provide recording of events in order to have legal evidence. It provides 24-hour, day/night surveillance allowing the crew to be deployed more efficiently with personnel being able to stay inside a protected, air-conditioned environment rather than having to stand watch on deck. Gatekeeper also allows the ship to have a relaxed alert state and still be able to respond quickly in case of an emerging threat, Gatekeeper excels in harbours and confined waterways where radar use is restricted and radar performance is limited. The 360°surveillance image is available for multiple operator stations, where each operator has his own 'software controlled window' for amplification of track data and zoom-in without disturbing the 360° view for other users at the bridge, operations room or watch stand. The panoramic view can also be displayed on large screen('s) in the combat information centre.

Belgian frigate Leopold I after the upgrade. Photo: Mike

SCOUT Mk2 LPI radar.
Photo: Thales
The SCOUT Mk2 is the integrated LPI radar, a short-to-medium range surface surveillance and tactical navigation radar. 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 featuring 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. A 1m2 can be detected at 5n.m., a 100m2 at 15.5n.m. The ships are also equipped with another X-band navigation radar, the Kelvin Hughes 1007, an auto-tracking radar with maximum instrumented range about 95n.m.

NH90 helicopter on a Dutch vessel. Photo: D-Mitch

Cougar helicopter on Chilean frigate. Photo: Danile Woods

Thales PHS36 sonar.
Photo: Thales
Thales Anaconda towed array
Photo: Thales
The frigates are equipped with a low frequency active and passive bow mounted sonar as well as they carry a variable depth towed sonar (VDS). The bow mounted sonar is the Thales PHS36 which forms an essential part in detecting submarine threats. Operated by one person, the PHS-36 sonar system is capable of operation in deep as well as in shallow waters, and can detect slow- as well as fast moving targets (automatic tracking of up to 12 targets, 360° coverage), be they in a surface duct or in deep water. The system performs very well under reverberation-limited and noise limited conditions and provides the operator with a comprehensive, noise free picture. The three modes of operation, which are the active continuous wave (CW) mode, the active frequency modulation (FM) mode and the passive mode, ensure a high detection probability and a low false-alarm rate. Two modes can be used simultaneously. The combination of pulse type and processing effectively suppresses reverberation, noise, and side-lobe effects. PHS-36 features various support functions, such as frequency analysis of demodulated noise (DEMON) in a preformed beam, as well as range prediction parameter extraction (RPPE).  Thales Anaconda  (TSM2970) is the VDS sonar that equipped the Dutch and Belgian vessels initially, a VLF passive tactical towed array system with a range of over the 150Km. The array is towed at a critical angle from a 3,000m cable, operating at a depth of 1000m. This system configures a digital wet-end, in service with the French Navy (DSBV-61A), with an advanced technology sonar receiver built around the Mangouste Mk 2 processor. This latter equipment was developed by Thales (former Thomson Sintra) to increase the performance of all sonars, particularly in automatic detection, narrowband analysis, automatic tracking, adaptive beam forming and self-noise cancellation.
LFAPS during trials on the Dutch frigate Van Amstel
The Thales Anaconda has been replaced in 2016-17 by the Low Frequency Active Passive Sonar (LFAPS) manufactured by Ultra Electronics Maritime Systems, one of the most advanced multi-static active/passive towed array sonar systems in the world today.

Frigate Van Amstel of the royal Netherlands Navy prior her modernization
Vigile APX. Photo: Thales
APECS EW antenna. Photo:
The Electronic Support Measures (ESM)  and Electronic Warfare (EW) are provided by different systems on the two variants (standard M class and modernized M class). The non-modernized ships, i.e. the Chilean and Portuguese frigates, are equipped with the Edo Corp. APECS-II/AR-700 active and passive ECM and ESM system while the modernized ships, i.e. the Dutch and Belgian frigates, use the new Thales Vigile APX, the latest generation Radar Electronic Support Measures (RESM) system from Thales. The APX system utilises the latest receiver and processing algorithms and delivers outstanding performance in today’s complex RF environments. All the vessels carry Raytheon AN/SLQ-25 Nixie towed torpedo decoys that consists of a towed decoy device (TB-14A) and a shipboard signal generator. The decoy emits signals to draw a torpedo away from its intended target.

SRBOC launchers on board frigate Van Amstel. Photo: D-Mitch

TDS. Photo: Thales
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. The decoy launchers are the BAE Systems Mk 36 Super Rapid Bloom Offboard Countermeasures (SRBOC) Chaff and Decoy Launching System. It is a shipboard, deck-mounted, 6-barreled 130mm mortar-type array that launches type-specific countermeasures against a variety of threats. Following launch and dispersion, Mk36 SRBOC chaff and infrared countermeasures are designed to lure hostile missiles away from ships under attack by creating false target sets. The Mk36 SRBOC launching system is controlled from the ship’s combat management system (see last paragraph), and it is dependent on information provided by the ship’s detection and threat analysis equipment. The Mk36 SRBOC consists of the Mk137 launcher, firing stations at the bridge and CIC, the Mk160 power supply, Mk5 Mod2 or Mod4 Ready Service Lockers (RSLs), and a selection of munitions. Each vessel carries four Mk137 launchers.

Frigate Van Speijk in the Gulf of Aden. Photo: Maersk Line Social
The combat management system (CMS) is the Thales Nederland SEWACO Mk.VII (Spider) while the ships feature a variety of communication systems such as Link 11, SATCOM, INMARSAT, TUUM-6 Under-Water Communication Equipment and others.

Nice photo of frigate Van Speijk before the modernization program. Photo: Thales


No comments:

Post a Comment