AFCON Corvette The Aegis Smallest Combatant Vessel

Transcription

1 AFCON Corvette The Aegis Smallest Combatant Vessel Author Names: Mr. Francisco Vilchez Programme Manager Combatant Vessels IZAR Construcciones Navales, S.A. Member of the Spanish Association of Naval Architects Mr. Michael J. Curry Director Spanish Project Bath Iron Works Member of the American Society of Naval Engineers Member of the US Navy League Mr. Michael A. Yerkes Director, Advanced International Naval Programs Lockheed Martin ABSTRACT Three worldwide industry leaders joined forces to create AFCON (Advanced Frigate Consortium), a trans-atlantic shipbuilding team. The team combines the expertise of IZAR, the Spanish Navy s prominent shipyard with large experience in design and construction of surface combatant vessels, Bath Iron Works (BIW), a General Dynamics Company and the United States Navy s preeminent surface combatant shipyard, and Lockheed Martin, a world leader in the design and integration of advanced combat systems. AFCON is committed to providing international customers with affordable Aegis Surface Combatant Solutions using state-of-theart technology and designs. One of the new products developed on the basis of the huge experience of the three companies is the AFCON Corvette, the smallest of the AFCON combatant ships family. The AFCON Corvette is an affordable, high performance surface combatant solution tailored to meet the littoral needs of navies operating around the world and represents a cutting edge technology design which integrates the very powerful and well-proven Aegis AAW system in the minimum sized platform. The aim of this report is to reflect the design drivers, main characteristics and ship capabilities that make the AFCON Corvette the best vessel of her class. 1

2 NOMENCLATURE LAM - Land Attack Missile LAW - Land Attack Warfare The following abbreviations have been used in this LC - Load Centre paper: LCAW - Low Cost Antisubmarine Weapon LCC - Life Cycle Cost AAW - Anti Air Warfare LCE - Life Cycle Engineering ABT - Automatic Bus Transfer LCS - Life Cycle Support AEW - Air Early Warning LM - Lockheed Martin AFCON - Advanced Frigate Consortium LRU - Line Replaceable Unit AIC - Air Intercept Controller MAMS - Maintenance Assistance Modules ANEP - Allied Naval Engineering Publication MBT - Manual Bus Transfer ARM - Availability, Reliability and MFC - Multi Function Console Maintainability NATO - North Atlantic Treaty Organization ASM - Anti Ship Missile NBC - Nuclear, Biological, and Chemical ASuW - Anti Surface Warfare NBCD - Nuclear, Biological, and Chemical ASW - Anti Submarine Warfare Defense BIT/FIT - Build In Test / Fault Isolation Test OTHT - Over The Horizon Targeting BITE - Build In Test Equipment PO - Petty Officer BIW - Bath Iron Works PTAS - Passive Towed Array Sonar CBM - Condition Based Maintenance RAS - Replenishment At Sea CCS - Centralised Control Station RCS - Radar Cross Section CCTV - Closed Circuit Television RIB - Rigid Inflatable Boat CIC - Combat Information Centre S&TE - Support & Tests Equipment CO - Commanding Officer SCC - Ship s Control Center CODAD - Combined Diesel and Diesel SHF - Super High Frequency COTS - Commercial off-the-shelf SM - Standard Missile CPO - Chief Petty Officer SSM - Surface to Surface Missile CPP - Controllable Pitch Propeller TIS - Target Illumination System CS - Combat System TTY - Teletypewriter DC - Damage Control TWT - Travelling Wave Tube DCS - Damage Control Station UAV - Unmanned Air Vehicle DDS - Design Data Sheet UHF - Ultra High Frequency DECON - Decontamination UMS - Unattended Machinery Space DTS - Data Transmission System VERTREP - Vertical Replenishment ECM - Electronic Countermeasures VHF - Very High Frequency EHF - Extra High Frequency - Vertical Launching System EMC - Electro Magnetic Compatibility VOA - VERTREP Operating Area EME - Electro Magnetic Environment XO - Executive Officer EMI - Electro Magnetic Interference EO - Electro Optical ESM - Electronic Support Measure INTRODUCTION ESSM - Evolved Sea Sparrow Missile FD/FI - Fault Detection / Fault Isolation The AFCON Corvette, the smallest of the AFCON GFCS - Gun Fire Control System combatant ships family, is a 102 m long monohull GMDSS - Global Maritime Distress & Safety System multi-mission ship, with a displacement of around 2,600 t, a maximum speed of 27 knots, steel hull and GPS - Global Positioning System superstructure, a CODAD propulsion plant, and an GRP - Glass Reinforced Plastic electric plant working in parallel or split mode. It is HIFR - Helicopter In Flight Refueling designed to provide helicopter and medical facilities, HMS - Hull Mounted Sonar excellent seakeeping characteristics and enhanced HVAC - Heating, Ventilation, and Air Conditioning survivability features, with special emphasis on minimising the radar, infrared, hydroacoustic and IBS - Integrated Bridge System magnetic signatures to obtain the most stealthy ICAS - Integrated Condition Assessment System corvette feasible. Special emphasis has been paid in the design on ship automation, human factors, ship IFF - Identification Friend or Foe supportability, life cycle cost and the use of IPMS - Integrated Platform Management System commercial off the shelf equipment, which have been considered as major factors in the design process. IR - Infra-red The vessel is a multi-mission small combatant IRSS - Infra-red Signature Suppression designed from the keel up to operate in the complex 2

3 79 waters of the littoral; either alone or as a part of a naval task force in conjunction with joint, allied and coalition forces. The AFCON Corvette represents a cutting edge technology design, which integrates a very powerful and well-proven AEGIS AAW system in a minimum sized platform. The ship includes growth margin to allow for a range of mission system upgrades. carrying an AEGIS system based on a SPY-1K phased array radar; the AFCON Corvette. The main goal of the integration effort is to install a full AEGIS-based Integrated Weapon System onboard a moderate displacement combatant ship. AFCON has successfully addressed this goal and the result is a range of ships designed around the AEGIS weapon system as shows the Figure 1 below. ADVANCED FRIGATE CONSORTIUM (AFCON) Three worldwide industry leaders have joined forces to create the Advanced Frigate Consortium, or AFCON. This alliance designs and manufactures affordable, state-of-the-art surface combatant ships for the Third Millennium. IZAR, the Spanish Navy s prominent shipyard, and Bath Iron Works (BIW) - a General Dynamics Company and the United States Navy s premier surface combatant shipyard, have joined Lockheed Martin (LM) Naval Electronics and Surveillance Systems, a world leader in the design and manufacture of advanced combat systems and modern shipboard phased array radars, to form AFCON. This alliance builds upon the impressive expertise of its three-team members. IZAR and BIW, with over 450 years of combined experience, have designed and manufactured the full spectrum of naval vessels, including aircraft carriers, destroyers, frigates and corvettes. Lockheed Martin has been designing and manufacturing advanced combat systems for more than four decades, including the AEGIS Weapon System and associated SPY-1D and SPY-1F phased array radars. AFCON offers AEGIS platforms that can easily integrate indigenously designed and manufactured weapons, sensors and hull, mechanical and electrical systems. AFCON designs its surface combatants with open or common architecture to easily accommodate future upgrades. The AFCON Team has extensive experience working with a host country s shipbuilding and electronics industries and has designed and successfully completed numerous technology transfer programs around the world. AFCON has designed AEGIS frigates and destroyers that range in size from the Spanish Navy s 6000-ton F-100 frigate and the U. S. Navy s 9500-ton DDG 51 destroyer, both with the SPY-1D phased array radar, to the 5000-ton Norwegian frigate, with the smaller SPY-1F phased array radar. Each of these ships has been designed with strict adherence to military standards. AFCON success leverages years of experience gained during numerous Spanish Navy shipbuilding programs, as well as from the U.S. Navy s AEGIS Ticonderoga cruisers and the Arleigh Burke destroyers. At present, the three AFCON members have joined forces to design the smallest ship capable of DDG DDG DESTROYER DESTROYER ARLEIGH ARLEIGH BURKE BURKE CLASS CLASS DISPLACEMENT DISPLACEMENT t t F-100 F-100 FRIGATE FRIGATE ALVARO ALVARO DE DE BAZAN BAZAN CLASS CLASS DISPLACEMENT DISPLACEMENT t t SPY-1D RADAR TOMAHAWK, SM-2 SM-2 & ESSM ESSM F-310 F-310 FRIGATE FRIGATE FRIDTJOF FRIDTJOF NANSEN NANSEN CLASS CLASS DISPLACEMENT DISPLACEMENT t t SPY-1D RADAR ESSM & SM-2 SM-2 AFCON AFCON CORVETTE CORVETTE DISPLACEMENT DISPLACEMENT tt SPY-1F RADAR Figure 1. Main Combat System components of the AFCON products. ESSM ESSM SPY-1K RADAR ESSM ESSM & SM-2 SM-2 The most salient characteristics of AFCON products as compared with other ships of similar displacement is cost-effectiveness. One of the major contributors to effectiveness is the inclusion of the AEGIS AAW system, normally installed in bigger and more expensive ships. AFCON CORVETTE MAIN CHARACTERISTICS Length Overall m Length on the Waterline m Maximum Beam m Beam on the waterline m Depth to main deck m Design Draft m Contractual Full Load Displacement t Future Growth Margin (5% Full Load) t Full Load Displacement including Future Growth Margin t Maximum Speed (Trials) kn Cruising Speed kn Range at Cruising Speed... 4,000 nm Total accommodation capacity MISSIONS The AFCON Corvette has been designed with the following operational capabilities as initial requirements: Conduct surface, underwater and air surveillance 3

4 Engage surface ships, submarines, aircraft, missiles, and land targets with own ship weapons Provide Command and Control for own ship Defend own ship with hard-kill and soft-kill weapons Respond to National Command Authority Interoperable with members of a Multi- National Battle Group DESIGN DRIVERS The Figure 2 shows the main drivers that have led the design process of the AFCON Corvette Concept. AEGIS CAPABILITY FLEXIBILITY SURVIVABILITY AUTOMATION growth margins have been incorporated from the start of the design process. The AFCON Corvette is designed with the objective of achieving a high degree of survivability by minimising the ship s signatures and its vulnerability and presents a high degree of automation for reduced manning. Several automation systems are employed including the Integrated Bridge System (IBS), and the Integrated Platform Management System (IPMS). Automation within the Combat System also contributes to reductions in the required manning. Several innovative measures are incorporated into the design in the areas of new materials, automation, signature control and equipment. A design-to-cost policy has been followed by combining rigid cost targets with the fulfilment of the critical and more relevant general performance requirements, with special emphasis on those related to survivability features, ship automation, human factors and ship supportability which have been considered also as leading factors in the design process. Finally, a Life Cycle Cost Reduction goal for the AFCON Corvette of 25% has been adopted. This represents the potential Life Cycle Cost savings to be obtained by a typical customer if they were to replace a similar ship currently in use in their Navy with the Corvette. This goal is based on reducing manning and fuel consumption, the two greatest contributors to Life Cycle Cost. Design criteria have been established for incorporating the most fuel efficient propulsion system components and configuration that will be capable of meeting all operational requirements. The result of all the design drivers mentioned above, is a cost effective solution specifically tailored to fulfil the performance requirements. INNOVATION DESIGN TO COST LOW RISK LIFE CYCLE COST SURVIVABILITY Figure 2. AFCON Corvette design drivers The Anti-Air Warfare System of the AFCON Corvette is an AEGIS system, based on the air surveillance and missile fire control capabilities provided by the SPY-1K multipurpose phased array radar. While smaller than the SPY-1D, it supports all the functionality of the AEGIS Weapon System. The AAW System also includes a four single-cell, tactical length Vertical Launcher System, capable of launching ESSM missiles in quad pack canisters and SM-2 or Sea Sparrow missiles in individual canisters, two slaved Target Illuminator Radars, and the AEGIS Missile Fire Control System. The ship incorporates a high degree of flexibility that allows the addition of both, enhanced Combat System configurations or alternative Platform System solutions. For this purpose prudent design and future Survivability is the capability of a weapon system to continue to carry out its designated mission in a combat threat environment. Survivability is a function of both susceptibility and vulnerability. Susceptibility is the combination of factors that determine the probability of hit by a given threat and is associated with the ship stealthiness and with its own self-defence capability. Vulnerability is the extent of degradation of a system after having been subjected to combat threat, that is, the degree of mission impairment as a result of sustaining levels of damage caused by weapon hits and is associated with hardening, system separation, redundancy, damage prevention and damage control management. Figure 3 gives an overview of the presented concepts and how they have been incorporated in the AFCON Corvette. 4

5 REDUCED UNDERWATER SIGNATURE MINIMISED RADAR CROSS SECTION SMALL IR SIGNATURE LOW MAGNETIC SIGNATURE SUSCEPTIBILITY STEALTHINESS SURVIVABILITY SELF DEFENCE POWERFUL COMBAT SYSTEM Figure 3. Survivability concept Susceptibility Reduction Measures The AFCON Corvette design incorporates measures to reduce the ship susceptibility by minimising: Radar Cross section signature. Underwater acoustic signature. Infrared signature. Magnetic signature. VULNERABILITY Maximum effort has been focussed on minimising the RCS signature of the ship. To decrease this signature, the superstructure sides are aligned with the hull sides and uncovered deck equipment is kept to a minimum. The foredeck and afterdeck are covered, and boat recesses are also covered by reflective meshes as shown in the Figure 4. Figure 4. AFCON Corvette general layout SHOCK RESISTANCE BALLISTIC PROTECTION NBC DEFENCE DAMAGE TOLERANCE DAMAGE CONTROL The above water hull knuckle has been arranged close to the waterline. This layout provides a minimum sea oriented hull area below the knuckle, improving the ship s RCS by reducing the possibility of seawater reflections. Special emphasis has been applied in the design of propellers and hull appendages for reducing the underwater noise signature. Stem and sonar dome areas are optimised for a minimum self-noise contribution and noisy equipment is installed on resilient mounts for attenuating the structure borne noise. The reduction gear is designed and built according to low noise naval practices. For reducing the Infrared signature, the exhaust gas system of each diesel engine is provided with an Infrared Signature Suppression System of the eductordiffuser type. A prewetting system is also used for cooling the hull and superstructure to minimise their contribution to the overall IR signature. An automatic degaussing system consisting of M, L and A coils is provided for reducing the magnetic signature, and an automatic impressed current cathodic protection system is fitted onboard to achieve a low underwater electric potential signature and to protect the ship from galvanic corrosion. Vulnerability Reduction Measures The design features exhaustive measures to reduce vulnerability, including system separation and redundancy, adequate watertight subdivision, appropriate Damage Control Zone subdivision, NBC protection for crew, features to control fire and flooding, shock protection and ballistic protection for critical spaces. The ship has an over pressurised citadel providing continuous protection against NBC warfare agents. This citadel is divided into three independent NBCD zones. The machinery compartments and bridge have been considered as sub-citadels. The AFCON Corvette has been designed for fulfilling the very demanding DDS Stability and Buoyancy of U.S. Naval Surface Ships standard for both intact and damage conditions. The hull has been subdivided in eleven main watertight compartments by ten main watertight transverse bulkheads, ensuring that a 15% length damage will limit flooding to a maximum of three main watertight compartments and providing a high degree of stability and reserve buoyancy. To minimise the vulnerability of the ship the sea water main and chilled water distribution systems are configured as loop systems. To achieve a high survivability, ballistic protection has been provided for the CIC, Ship Control Centre, Bridge, Magazines, Weapon electronic spaces and communication rooms. The incorporation of many features to minimise susceptibility and vulnerability provide the AFCON Corvette with an excellent survivability performance more commonly associated with frigate size ships. TOP DECK DESIGN DRIVING FACTORS The following main design drivers have governed the definition of the AFCON Corvette Top Deck Design: One superstructure block: The superstructure will have a continuous 01 Level deck and one superstructure block of relatively short length above this deck. This structural arrangement provides a superior global stress path under ship bending loads, reduces ship flexure vertical deflections, and permits lighter scantlings to be used. 5

6 Helo integration on ship platform: The AFCON Corvette is designed to handle (landing, securing, fuelling and starting) a medium helicopter (NH-90 or similar). The Helo Deck occupies the astern area. Minimise RCS: To reduce the ship Radar Cross Section shaping techniques have been thoroughly applied in the design. The superstructure and solid mast sides have been sloped inwards and the main surfaces are oriented to the main azimuth directions, i.e. either longitudinally or transversely. Those superstructure surfaces not oriented in the main azimuth direction are parallel to the surfaces that support the SPY-1K arrays to limit the RCS contributions to a minimum number of azimuth and elevation angles. Minimise IR signature: A single funnel configuration has been selected for minimising the potential impingement of exhaust plumes in the superstructure. The funnel has been arranged taking into account the following main considerations: - Vertical intake and exhaust ducts for main diesel engines. - Minimise impingement on weapons, sensors and ship s structure. - Minimise smoke over the flight deck. - Dimensioned for installing IRSS devices. The adopted solution combines the casings for both main engine rooms in a single funnel above the 02 Level, in the amidships area. Minimise mast vibration through appropriate structural continuity: In general, structural transverse bulkheads in the superstructure will be in the same plane at all levels and will line up with the supporting transverse bulkheads in the hull. Wherever practicable, structural longitudinal bulkheads in the superstructure will be aligned with stiffening in the deck below. Location of weapons and sensors derived from coverage arcs and EME considerations: The selected positions of the weapons and sensors provide the maximum coverage arcs in combination with the maximum achievable safety of personnel. Provide the required clearance for missile launch dispersion envelope: The longitudinal position of the launcher provides the required clearance for the missile launch dispersion envelope. Provide the required distances between weapons and ship structure to minimise blast effects: The weapon locations take into account the blast effects produced by own weapon firing. Provide adequate distances between sensors and main exhaust: Antennas are separated from the exhaust gases outlet to avoid high temperatures. The separation also takes into account transmission and reception requirements as well as EMC/EMI. Provide the required area for seamanship operations (liferafts, RAS, transport routes): The required areas for liferaft stowage, RAS operations and transport routes have been reserved in the weather decks. These decks are flat and without any unnecessary obstacles to improve the seamanship operations and the radar signature of the ship. TAS DECOY LAUNCHERS TORPEDO TUBES (P&S) TARGET ILLUMINATOR 20 MM GUNS SHF SATCOM (P&S) SSM LAUNCHERS (P&S) ESM IFF HMS SPY-1K RADAR TARGET ILLUMINATOR LCAW Figure 5. AFCON Corvette topside arrangement PLATFORM DESCRIPTION ESSM & SM-2 76 mm GUN The AFCON Corvette is a four-deck ship with one superstructure block above the 01 level and has been designed with the objective of achieving the highest performance characteristics as reflected in the following sections. Hull Form Characteristics The ship lines are based in the hull form systematic variation series named Bazán-82. This systematic series was developed from a model parent optimised from the resistance and seakeeping point of view. Eighteen models were tested with and without appendages in order to quantify the effect on ship resistance of hull form systematic variations. The final lines have been further corrected in order to incorporate some details enhancing the performance in smooth water by adapting a stern wedge as well as in rough water by increasing the waterline area. Forward flare is designed for minimizing the occurrence of deck wetness. In order to optimise the seakeeping performance, the ship is fitted with relatively high aspect ratio bilge keels, as well as with a pair of active stabilising fins. Both the bilge keels and the stabilising fins will reduce the roll motion and the related lateral acceleration significantly when compared to a ship without any damping device. Hull Structure Concept Both ship s hull and superstructure are made of welded steel. A continuous 01 Level strength deck extended from the aft limit of the superstructure to the bow has been arranged. This strength deck provides a 6

7 sounder global strength path and a high ship s survivability after weapon hit. Hull plating and internal reinforcements will be of High Tensile Steel (355 N/mm 2 ). Extra High Strength Steel (460 N/mm 2 ) grade DH or EH, will be used in special areas, to act as crack arrestors or ballistic protection. The after part of the Main Deck is designed in accordance with DDS Scantlings permit parking, landing and take-off operations in Moderate sea conditions for a medium sized helicopter. Figure 6 below shows the MAESTRO finite element model developed for the AFCON Corvette hull structure design. Figure 6. AFCON Corvette MAESTRO finite element model Propulsion Plant Concept The ship propulsion system is a combined Diesel and Diesel (CODAD) type driving two Controllable Pitch Propellers (CPP). Each propeller is driven by two propulsion diesel engines (6320kW each), one gearbox and the associated equipment. The ship has two Main Engine Rooms where the prime movers of both shaft lines are arranged. Additionally, two Diesel Generator Sets Rooms are located astern and forward of the Main Engine Rooms. Figure 7 below shows the main propulsion machinery layout. Figure 7. AFCON Corvette main propulsion machinery layout The possible operating modes of the propulsion plant will be: Two diesels each to its corresponding shaft. Single diesel to its shaft. A central area is used as the casing for both Main Engine Rooms allowing the conveyance of the combustion air (directly ducted from the weather) and the exhaust gases of main and auxiliary engines. Exhaust ducts are provided with adequate silencers and Infra-Red Suppression Systems for reducing the mass flow average temperature of the mix of the cooling air and exhaust gases. The Engine Rooms are unmanned. One ship control centre (SCC) and two damage control stations (DCS) are provided. Normal operation takes place from the SCC that incorporates the main Damage Control Centre as well. In case of technical failures or partial damage to the platform systems, the systems that remain in operation can be controlled and monitored from the SCC or the local control panels with a minimum increase in human resources. Electric Plant Concept The electrical plant is composed of four diesel generator sets of 550 kw, 440 V, 60 Hz, three phases, two mounted in the Forward Diesel Generator Sets Room and two mounted in the Aft Diesel Generator Sets Room. These rooms are separated by two watertight compartments and one damage control zone ensuring that at least half of the electric power generation will be available with three compartments flooded. The switchboard rooms are interconnected and located in the same main watertight compartment as the generator sets. The electrical plant is able to supply the maximum load with three generators running at 90% of the rated power in order to allow for distribution system unbalance during parallel operation. The power distribution system (440 V, 60 Hz) is a radial distribution system combined with a zone distribution system. In this distribution system the main switchboards are the starting points for assigning feeders supplying load centres and individual loads. The load centres are distributed along the ship taking into account the zone distribution in such a manner that each zone contains one or more load centres for supplying power panels and individual loads within the zone. Some other loads, such as the steering gear or some of the fire pumps, can be supplied directly from the main switchboards. The vital systems for survivability are supplied from both main switchboards through ABT (Automatic Bus Transfer) switches and the vital systems for the mission through MBT (Manual Bus Transfer) switches via load centres or directly from the switchboards. The normal and sheddable loads are supplied from only one main switchboard. The plant incorporates facilities for automatic starting and synchronisation and parallel connection of the main generators. The plant can work in parallel or split modes. Figure 8 shows the electrical distribution of the AFCON Corvette. 7

8 G3 550 kw 440V, 60 Hz 550 kw 440V, 60 Hz MAIN SWITCHBOARD N2 440V, 60 Hz SHORE BOX G4 AFT D. GEN. SETS ROOM L. C.: 1 ABT VITAL LOADS MBT VITAL LOADS SHEDDABLE LOADS L. C.: 6 ABT VITAL LOADS MBT VITAL LOADS SHEDDABLE LOADS INTERCONNECTION TWO WATERTIGHT COMPARTMENTS MAIN SWITCHBOARD N1 440V, 60 Hz SHORE BOX FWD D. GEN. SETS ROOM G1 550 kw 440V, 60 Hz G2 550 kw 440V, 60 Hz Figure 8. AFCON Corvette electrical distribution scheme Two static converters are arranged to maintain the helicopter and for the navigation and combat system. Each one is connected to one main switchboard and is dimensioned for supplying the total load. Auxiliary Systems Concept The integrated Heating, Ventilation, Air Conditioning (HVAC) and Nuclear, Biological and Chemical (NBC) systems control the ship internal ambient conditions and provide continuous protection against NBC warfare agents over a period of 30 days. The HVAC and NBC systems have three separate zones with their own NBC filtered air supply. Outside air passes through the NBC Air Filtration Unit into an over-pressurised Citadel. A duct distribution system supplies filtered air to the living and working spaces from NBC filter stations or from air treatment units located in the same NBC zone. The main engine and diesel generator sets rooms are designed for continuous protection against NBC warfare agents. Each main engine room and diesel generator sets room has an independent ventilation system for the control of temperature, air purity and air movement. The machinery spaces ventilation system consists of seawater cooling air coils, fans, filters and distribution ducting for each main engine room and diesel generator sets room. Two chilled water plants and one chilled water distribution system is provided to cool down the heat load from the air conditioning system and direct water cooled equipment. Each chilled water plant is capable of providing 60% of the total load. The Chilled Water System consists of a pressure chilled water supply ring main and a return ring main. The Firemain System is arranged as a vertical loop system. It is possible to separate the system into three independent sections, each one fed from one or more pumps. The firemain pumps are positioned in separate watertight compartments. Each Damage Control Zone has its own electrical firemain pump. Sprinkler Systems are provided to protect ammunition, other hazardous storage areas and missile vertical launching system (). A Washdown System for cleaning the weather deck, superstructure, and other exposed spaces is provided. The system may be divided into three zones by remotely operated valves and is fed from the firemain system. Two Cleansing (DECON) Stations are arranged aft and forward in the ship, prior to entering the citadel. The Drainage System provides the means for removal of flood water from the compartments below the damage control deck and is capable of controlling flooding generated by firefighting. A Ballast system is provided to maintain and correct the ship s draft and trim and for providing the necessary stability for all operating conditions by transferring sea water in and out of the selected water ballast tanks. The potable water is generated by two reverse osmosis plants, each capable of meeting the total ship demand. An Aviation Fuel System is provided for the filling, storage and treatment of aviation fuel. The aviation fuel system provides the means for refuelling and defuelling the helicopters and for undertaking Helicopter In-Flight Refuelling (HIFR) operations above the after portion of the flight deck. The AFCON Corvette is provided with two identical steering gear units electronically synchronised which are capable of moving the rudders at the specified speed and conditions. A pair of recesses, one at each side, is provided into the superstructure block for boat stowage and handling equipment. The recesses are covered for minimising their contribution to the RCS. The ship has the necessary facilities to land, secure fuel and start a medium helicopter (less than 10 tons). As an option the ship can be provided with hangar and helicopter handling system for hosting a small helicopter (Lynx type). Two portable light solids RAS positions aft (one on each side of the flight deck), capable of receiving stores, ammunition and personnel and two liquids RAS positions amidships capable of receiving fuel oil, aviation fuel and potable water simultaneously have been arranged. On the flight deck one VERTREP area is provided. For handling stores and equipment, one 500 kg capacity elevator is extended between the Main deck level and the Tank Top level in the forward stores area. In the aft part of the superstructure, facilities to support two divers are incorporated. All environment pollution control systems are designed to comply with MARPOL requirements. 8

9 Interior & Equipment Concept An impressed current cathodic protection system minimise the corrosion of the underwater hull. The ship has been designed to accommodate a crew of 80 persons, including the helicopter aircrew and a board and crew margin of 10 persons. The following accommodation standard has been applied: Commanding Officer (CO): Sleeping cabin and day cabin. Executive Officer (XO): Sleeping cabin. Officers: Double cabins. CPO's: Quadruple cabins. PO's and ratings: Quadruple cabins. Standard sanitary units are integrated in the CO, XO, Officers and CPO s cabins. The PO s and Ratings accommodation areas are provided with shower/washbasins spaces (bathrooms). Commissary spaces include galley, CO pantry, Officers pantry and scullery. Figure 9 displays the specific accommodation areas per ranks and reflects the high habitability standard provided as compared with the mean values recommended by NATO standard. system. Leveraging this investment, the team can offer a high performance product at a lower price and far less risk than other ships providing comparable performance. The remaining warfare areas are well balanced, providing excellent multi-mission capability. The SPY-1K radar and associated automation and integration provide a superior degree of situational awareness unmatched by any other system, and essential when operating in any area of potential hazard or value to any nation. This is particularly useful in missions which require coastal surveillance or protection of borders. As appropriate for a Corvette, this radar is a scaled version of the U.S. Navy s SPY- 1D, and is about ¼ of its size and weight. Its instantaneous beam steering minimizes reaction time and provides concurrent volume and horizon search and tracking of targets, and simultaneous fire control tracking of targets while also providing uplink and downlink communications with midcourse guided missiles. Figure 10 shows the integration in the AFCON Corvette of the SPY-1K main equipment. AFCON CORVETTE.- SPECIFIC AREA DISTRIBUTION PER RANKS AFCON CORVETTE.- SPECIFIC AREA DISTRIBUTION PER RANKS Specific Area (m2/pers) Specific Area (m2/pers) 35,00 35,00 30,00 30,00 25,00 25,00 20,00 20,00 15,00 15,00 10,00 10,00 5,00 5,00 0,00 0,00 COMMANDING EXECUTIVE OFFICER OFFICERS C.P.O RATING COMMANDING OFFICER EXECUTIVE OFFICER OFFICERS C.P.O RATING OFFICER RANK RANK Total Area Total Area Rest & Recreation Rest & Recreation Dining Dining Sanitary & Access Sanitary & Access ANEP ANEP24: 24: Min. Min m 2 /p 2 /p Very Very high high specific accommodation area: area: m 2 2 per per person Figure 9. AFCON Corvette specific accommodation area The ship has a sickbay for providing facilities for activities such as medical examination, treatment and maintenance of medical records and medicine storage area. The ship is provided with two Damage Control Stations, one forward and one aft, above the Damage Control Deck. In the Ship Control Centre, a damage control console is installed for control/monitoring during normal navigation periods. Two personnel cleansing stations (decontamination centres) are provided. COMBAT SYSTEM DESCRIPTION The AFCON Corvette has been designed around a variant of the U.S. Navy s AEGIS Weapon System. The U.S. Navy has invested over $10B in the development and continued evolution of this ultra rapid reaction time, high firepower Anti-Air Warfare Figure 10. Integration onboard of the SPY-1K main equipment Anti-submarine warfare, electronic warfare, and anti-surface warfare are fully supported by modern sensors and weapons, and integration of the data within the Combat Management System. Particular attention has been paid to torpedo and mine detection and avoidance. The Combat Management System has also been designed so that operations can be conducted in all warfare areas simultaneously. The AFCON Corvette incorporates full Aegis functionality with capacities commensurate with its size and mission. This functionality allows the system to defeat the stressing AAW threats and ensure survival of the ship to complete its missions. It also provides the flexibility and growth capability to evolve to counter the threats which will present themselves over the year lifetime of the ship. In addition to the baseline system, extensions have been examined to provide enhanced capabilities in one or more warfare areas. These will be described below, and are presented by warfare area. The ship has been 9

10 designed with these enhancements in mind, and will still provide the necessary ship service and future growth margins necessary. This affords the clients the opportunity to increase the capabilities in the desired warfare area or areas while retaining the favorable total tonnage, cost, and crew size. Combat System Baseline The Anti-Air Warfare System for the baseline and all the enhancements is a variant of an AEGIS system, as described above. The AAW capabilities include a four single-cell, tactical length Vertical Launching System, capable of launching both ESSM missiles in quad pack canisters and Sea Sparrow missiles in individual canisters, two slaved Target Illuminator Radars, and the AEGIS Missile Fire Control System. The Anti-Submarine Warfare main sensor is a Hull Mounted Medium Frequency Fire Control Sonar with small object avoidance capability, complemented by a towed torpedo defense system. The main ASW weapon is a lightweight torpedo (MK-46, Stingray, MU-90 or similar) launched from one of two triple trainable torpedo launchers. The ASW suite is controlled by an Anti-Submarine Control System. The Anti Surface Warfare suite is composed of the Electro Optical Gun Fire Control System, the stealth version of the 76 mm Super Rapid Gun and two 20 mm machine guns. The Electronic Warfare system is composed of a Radar ESM system and four decoy launchers able to launch chaff, flares and torpedo decoys. The above systems are controlled and managed using the Combat Management System, several Multipurpose Processing Cabinets and Multifunction Consoles. The ship is fitted also with an integrated communications system covering the UHF, VHF, EHF and SHF bands and capable of transmitting and receiving secure and plain voice, TTY and Link 11 tactical data. Figure 11 below shows the Baseline Combat System configuration. Integrated Navigation System Electronic Warfare Sensors Identify Friend or Foe Phased Array Radar Electro Optic Sensor Hull Mounted Sonar Towed Torpedo Towed Array Alertment Array ASW/ASuW Coordinator Acoustic Operator TIC/RC/MHS Command Console AAW/MFCS Coordinator GFCS/EO Helicopter Communications Electronic AAW Countermeasures ESSM Target Illuminators ESSM Launcher Torpedo Countermeasures Main Gun Torpedo Launcher Figure 11. AFCON Corvette baseline Combat System configuration Combat System Variants In addition to the baseline capabilities, it is feasible to include additional or upgraded systems to improve performance in a specific warfare area. For the AFCON Corvette, four enhanced combat system variants have been studied and shown to be feasible. These variants include the Enhanced AAW Variant, Enhanced ASW Variant, Enhanced ASuW Variant, and Enhanced LAW Variant. Finally, an Enhanced Multi-Mission Variant is also considered to evaluate the effect of simultaneously improving performance in all warfare areas. This Variant includes some additions from all of the warfare area variants. Figure 12 summarizes the contemplated Combat System Variants. LCAW UAV ASW VARIANT HANGAR HANGAR PTAS 2 x 4 LAM PREPARE SHIP FOR ASW HELO NIXIE LAND ATTACK VARIANT EO + RADAR GFCS 127 mm GUN 4 CELLS TACTICAL HMS - MF FC TORPEDO DEFENSE 2 x 3 TORP. TUBES BASELINE IFF DECOY LAUNCH. COMBATSS LINK-11 ES M EO GFCS 2 x TIS SPY-1K 2 x 20 mm MACH. GUN 76 mm GUN AAW VARIANT INCREASE CELLS EO + RADAR GFCS ASuW VARIANT EO + RADAR GFCS 127 mm GUN PREPARE HELO FOR AEW PREPARE C.S. FOR S M-2 RADAR ECM HELO OTHT INCREASE SPY TRANSMITTER POWER 2 x 4 SSM HELO AS M MFC FOR AIC Figure 12. AFCON Corvette Combat System Variants Enhanced AAW Variant The Enhanced AAW Variant provides even greater self-defense and area air defense capabilities. This is accomplished through the addition of 2 transmitter TWT tubes to the SPY-1K transmitter group and an increase in capacity to a maximum of 16 tactical length cells. This combination enables the use of SM2 missiles for area defense, and additional ESSM missiles for improved self-defense. The Enhanced AAW Variant may also include an extra console for an Air Intercept Controller, a DORNA fire control radar, and a Radar Active ECM system. Enhanced ASW Variant The Enhanced ASW Variant improves the Corvette s ASW detection, engagement, and evasion capabilities through the addition of a Nixie towed decoy, an active towed sonar array, and a Low Cost Anti-Submarine Weapon. In addition, this variant includes a hangar and helo handling system for an organic light helicopter, and provides stowage space for extra torpedoes and sonobuoys. Enhanced ASuW and Land-Attack Variants The Enhanced ASuW and LAW Variants are considered together in this section due to their similarities. In the Enhanced ASuW and LAW variants, the 76 mm Gun is replaced with a 127 mm gun, and 8 Surface to Surface or Land Attack missiles HANGAR 10

11 are added. In addition, an organic helicopter or UAV is used to provide over-the-horizon targeting and spotting. Enhanced Multi-Mission Variant The Enhanced Multi-Mission Variant provides a marked performance increase in all major warfare areas. The increased power for the SPY-1K coupled with additional cells and the SM2 provide Area Air Defense and improved self-defense capability. The addition of the active towed array, NIXIE decoy, a helicopter, and additional ASW ordnance improves detection, evasion, and engagement capabilities against submarines. Eight SSM or LAM launchers provide strike capability not present in the baseline configuration. The Enhanced Multi-Mission Variant is highly capable in all major warfare areas, and provides capabilities greater than most frigates. MANNING AND AUTOMATION The AFCON Corvette incorporates a high degree of automation for reduced manning. In addition to the Combat System, the key automated shipboard systems are the Integrated Bridge System (IBS), and the Integrated Platform Management System (IPMS). The IBS is a collection of Navigational equipment such as GPS, Meteorological, electronic charts and mapping capabilities, dual band ARPA Radars, GMDSS System and many other elements. These elements are combined into a data exchange network, which is also common with the IPMS data network. This network is the DTS or the Data Transmission System. The IPMS is the platform management system and affords the AFCON Crew the ability for unmanned engine spaces by allowing automation and control functions of the main propulsion, auxiliary, and electrical plant systems. Data from equipment sensors are passed through to the IPMS control consoles via local substations, and processed in any one of the IPMS consoles. Therefore, a single operator may maintain the entire platform from his/her workstation located in the Ship Control Center (SCC). The DTS is the heart of the control system and is broadband technology allowing for the simultaneous transmissions of data, video, and other signals if required (see Figure 13 below). This redundant data distribution system affords the vessel with a high degree of bandwidth for future expansion, and minimises the need for multiple data systems to support multiple data types. LSS Shore Connection SCC Consoles Fieldbus LSS Fieldbus Bridge Console ATM 2 ATM 1 ATM 3 DC Consoles Remote Locations (Laptops) LSS Fieldbus Figure 13. AFCON Corvette DTS block diagram Other systems to assist in the reduction of manning are the CCTV system. This system minimises the need for a large security detail when in port and can assist the crew in looking in on typically unmanned spaces. Advanced technology using wireless computers embedded in fire fighting gear affords the AFCON crew with up-to-the-second data when performing damage control evolutions. Data includes items such as where the damage is progressing and compartment check off lists for isolating spaces. Increased communications and information distribution is key for a reduced crew in damage control evolutions. The sources of information used in the AFCON manning allocation were largely drawn from the USCG manning concepts, Experienced Spanish Submarine Navy sources, US and Foreign Commercial Shipping Manning Philosophies and high level reduced manning concepts from the United Kingdom, Australia, Canada and the U.S. Navies. The results of the manning analysis are summarised below in Table 1. Although the total available accommodation provided clearly exceeds the results obtained in the manning study, it is important to highlight that the presented results do not include either the Helicopter detachment or additional personnel required for enhanced Combat System Configurations. Military Rank Manning Results Total available accommodation Commanding Officer 1 1 Officers Chief Petty Officers PO & Ratings TOTAL Table 1. Results of AFCON Corvette manning analysis 11

12 LOGISTICS The primary goal of the AFCON Corvette in the logistic area is to produce a baseline multi-mission capable ship that exhibits an Inherent Availability greater than 92% while achieving a 25 % reduction in Life Cycle Cost. The platform and combat system design will provide for flexibility to meet individual customer needs. Differences in fleet size, operating practices, support infrastructures, maintenance concepts, geographic location, size of operating areas, and training levels represent a partial list of the challenges requiring the Corvette to be designed for supportability. AFCON s approach to Life Cycle Engineering (LCE) and Life Cycle Support (LCS) activities associated with the development, production, delivery, and post delivery support ensures that the Corvette will meet or exceed all Operational and Supportability requirements at a lower Total Ownership Cost. Through an integrated approach to the development of LCE and LCS requirements the AFCON Corvette project will benefit from reduced costs and improved operational availability. Life Cycle Engineering (LCE) consists of defining the System Operating Requirements and Maintenance Concept, and performing Availability, Reliability, and Maintainability (ARM), Provisioning, and Life Cycle Cost analyses. These analyses are integrated into the design process to ensure that the baseline ship, and any combination of options and extensions, is maintainable, supportable, and capable of achieving its Manning reduction will be accomplished through automation and reduced onboard maintenance. Methods of reducing Life Cycle Cost include: Prognostics and Equipment Health Monitoring Redundancy and Graceful Degradation Conditioned Based Maintenance (CBM) No, or Minimal, On-Board Maintenance Equipment Not Requiring Preventive Maintenance BITE, BIT/FIT, FD/FI, Faults Isolated to a Single LRU Automatic Switch-Over/Re-Configuration No, or Minimal, S&TE Deferred Maintenance (To Pierside) Six Month Preventive Maintenance Intervals Remove & Replace On-Board, Repair On- Shore On-Line Help Tutorials Integrated Condition Assessment System (ICAS) No, or Minimal, Alignments No, or Minimal, Spares and MAMS Maintenance and Support Concept Maintenance and Support concepts identify and drive the range and depth of all Lifetime Support Program requirements. These concepts specify the level, repair philosophy, and logistic support requirements that will be incorporated into the Maintenance Plan for the Corvette. Provisioning, spares, supply replenishment times, support equipment overall mission. requirements, manpower utilization, and many other Life Cycle Support (LCS) consists of the logistics functions are dependent upon the processes that support the requirements identified in maintenance concept employed. the Life Cycle Engineering analyses. It includes The goals established for the Corvette development of the Maintenance, Training, Supply Maintenance Concept are to maximize availability of Support, and Configuration Management Plans. They the ship and her systems, reduce the crew workload, define the processes that ensure that the Supportability and reduce life cycle cost. requirements identified in the Life Cycle Engineering The following guidelines have been used to analyses are properly implemented throughout the support these goals: lifecycle of the ship. High effectiveness of equipment with minimal on board maintenance Life Cycle Cost On board maintenance performed during The Life Cycle Cost Reduction factor goal for the availability work periods to the greatest AFCON Corvette is 25%. This represents the Life degree possible Cycle Cost savings potential realized by a typical Maximum use of BIT/BITE and self customer if they were to replace a similar ship diagnostic technology currently in use in their Navy with the Corvette. Maintainer/Operator concept to be used This goal is based on reducing manning and fuel consumption, the two greatest contributors to Life Cycle Cost. It was derived from comparisons between the Corvette and target customers ships that have similar physical, performance, and mission capability characteristics. Design criteria have been established for incorporating the most fuel efficient propulsion system components and configuration that will be capable of meeting all operational requirements. where possible Maximize standardized equipment (i.e. COTS) Use of Condition Based Maintenance 12

13 ADVANCED TECHNOLOGIES AND INNOVATIONS Several innovative measures and advanced technologies are incorporated in the design in the fields of new materials, automation, signature control and new equipment. The following paragraphs summarise some of them. New Materials The use of composite materials in the superstructure or specific superstructure areas can be incorporated in the AFCON Corvette. Specific applications such us GRP bulwarks, ladders or false floors can be also implemented in order to reduce the ship weight. Automation Techniques The AFCON Corvette presents a high degree of automation for reduced manning. Several automation systems are employed including the Combat System, the Integrated Bridge System (IBS) and the Integrated Platform Management System (IPMS). Condition Based Maintenance and Predictive/Preventive measures will be integrated with the IPMS via the use of vibration sensors, which can be either portable analyser, hardwired or wireless type. This reduces the maintenance workload of the crew. CCTV systems are also employed for minimising the crew workload and provide an even higher level of situational awareness for damage control teams. Wireless computers embedded into the bunker gear uniforms can be used for providing critical compartment information to the DC teams such as compartment data, check off lists and communications. Access to the IPMS information can be obtained through a secure wireless link to that system. Wireless telephone systems can be installed to allow the crew to be in contact with each other at all times for supplementing the internal communication system. A Spectra Phone System or other suitable system can be installed. Signature Control Measures In addition to the measures introduced for minimising the ship s IR, electric and magnetic signatures, considerable effort was focussed on minimising the RCS. The application of tridimensional grids for covering the air intakes of the funnel and the use of fine reflective meshes or special doors for covering the RIBs and torpedo magazine recesses are examples of new or recent technologies incorporated in the design in the area of the signature control. The construction of a GRP mast above the 06 level and the totally enclosed arrangement of the SSM launchers are also examples of additional and innovative measures for controlling the RCS signature. With respect to the acoustic signature, Vibration Monitoring for specific equipment will be incorporated and will allow for the selection of the low noise plant configuration during ASW operations. New Equipment The AFCON Corvette design incorporates retractable or portable type mooring equipment to be used in the aft area for minimising the equipment on the weather deck that can impair the RCS signature. The ship also incorporates COTS equipment to the maximum extent. The reason for this is the fact that specification of such components invariably results in savings in LCC in comparison to unique Governmentspecified designs. Care will be taken in the specification of COTS to insure that early obsolescence of the material does not increase operating and repair costs. Examples of COTS equipment introduced in the AFCON Corvette are the IPMS PC based consoles integrated into rugged enclosures suitable for marine/military applications and the internal cameras of the CCTV system. Perhaps the greatest innovation in the AFCON Corvette is its combat system. This 2600 ton platform incorporates all the functionality of the U.S. Navy s powerful AEGIS system, giving it extremely rapid reaction time, high firepower, and the ability to sail in harm s way. The ship was designed around this fully integrated combat system, resulting in a compact, highly capable corvette - the most capable of its class. CONCLUSIONS The AFCON Corvette is designed with the objective of achieving a high degree of survivability by minimising the ship s signatures and its vulnerability. The incorporation of many features to minimise susceptibility and vulnerability provide the ship with excellent survivability performance more commonly associated with frigates and larger size vessels. The ship incorporates a high flexibility that allows the addition of both enhanced Combat System configurations or alternative Platform System solutions. For this purpose prudent design and future growth margins have been incorporated from the start of the design. The vessel incorporates a high degree of automation for reduced manning. Several automation systems are employed including the Combat System, the Integrated Bridge System (IBS) and the Integrated Platform Management System (IPMS). A base crew of 60 persons (without including the helicopter detachment) has been determined via a manning analysis. The ship has a high habitability standard when compared to a modern Naval Ship. Human factors were also carefully taken into account in the design. The baseline Combat System of the AFCON Corvette is a well balanced system in all the warfare areas with enough growth margin to receive some 13