Design
The frigates were built to a modern stealth design to avoid enemy radar and infrared detection. In addition to these features, the Meko A-200SAN class is distinctive with a very new propulsion system which is composed by a water-jet drive, in addition to two propellers. Its CODAG-WARP system (COmbined Diesel And Gas turbine-WAter jet and Refined Propellers) consist of a steerable propeller and a water jet. The power is provided by a combination of diesel engines and gas turbines. The propulsion plant can be operated in four modes:
- I – Economical mode: One diesel engine driving both shafts, maximum propeller speed: 150 rpm.
- II – Maneuvering mode: Both diesel enginess driving both shafts, maximum propeller speed: 200 rpm.
- III. CODAG-WARP: Both diesel engines and the gas turbines turned on, maximum propeller speed: 215 rpm.
- IV – Gas turbine only: Gas turbines powering water jet only.
These frigates are expected to spend about 80% of their at-sea time in modes I and II.
The ship's steering gear consists of a steering unit and twin semi-balanced underhung rudders. There is an emergency steering station in the superstructure in the event of damage to the bridge and they can also be operated by hand from the steering gear compartment. To improve the ship's performance in a seaway, they are fitted with a B+V Simplex Compact stabiliser system.
This class of warship has seven independent Noske Kaeser air-conditioning plants allowing the ship to operate at a preset temperature and moisture level in ocean water ranging between 4 °C and 30 °C, and the air temperature between −4 °C and 32 °C. This also keeps the air pressure in the citadel five millibars higher than on the outside to prevent the drawing in of RBC (radioactive, biological, or chemical) contamination. These ships are also fitted with Sulzer und Weise seawater fire-fighting pumps and sprinkler systems. These are also ready to wet down the warship's ammunition magazines. In addition, a CO2 fire-extinguishing system protects the gas turbine and diesel engineering areas. The galleys are fitted with an ANSUL system and the flight deck and hangar with a Noske Kaeser Hy FEx foam fire extinguishing system. Two Pall Rochem reverse-osmosis plants generate 15 cubic meters of fresh water each every 24 hours. This water is provided to the galleys, messes, and drinking water supplies, and it is also used for cooling the guns, the air-conditioners, and the engine room, in addition for washing the helicopters. Water pumped to the guns, sensors, and air-conditioners is chilled by two Noske Kaeser refrigerators. An oil-fired hot-water boiler, made by the same company, provides the ship's heating, whereas the hot water for the galley and messes comes from a 600 liter, 45 kilowatt electric geyser.
This class of warship is conspicuous for a lack of any funnels. To add to their stealth characteristics, the exhaust fumes from the Meko A200's gas turbines and diesel engines are cooled by spraying water into the exhaust duct and then expelled just above the ship's waterline, making the frigate almost invisible to most infrared detectors. In 2004, the project officer Rear Admiral (J.G.) Johnny Kamerman explained that the ships’ design features incorporated stealth characteristics that gave the Valour-class very low radar, acoustic, and magnetic signatures. "It is the first major warship in the world with a horizontal exhaust and water jet propulsion, and has an X-form outer hull," he said. Its manufacturers added that the design has the radar cross-section of a missile patrol boat, a 75% lower infrared signature than previous designs, as well as a 20% lower life-cycle cost, 25% less displacement and 30% fewer crewmen. The lack of funnels also frees up desirable room amidships for armaments, crew quarters, and store rooms.
This class's combat-management system (CMS), which apparently accounts for about 40 percent of each warship's cost, was purchased from the Thales Detexis company. The Tavitac system is also fitted to the French Navy's La Fayette-class frigates, and updated versions are aboard the Saudi Arabian F3000-class air-defence frigates, and the French nuclear-powered aircraft carrier Charles de Gaulle. Kamerman said that he was very proud of the ships' combat system and the South African ingenuity that went into their design. "Seventy-five percent of the combat suite is home-grown. It's the largest local-content percentage of all the defence packages. The local content makes testing and integration so much easier. The foreign stuff must be done in a tight time-frame and flying their experts here is expensive. The guys who built our radars are just 40 km away in Stellenbosch," Kamerman said of Reutech Radar Systems, one of the contractors. Local content also speeded up repair and maintenance. "It is local support in-country, not a local capacity created artificially or a bunch of foreigners flown in."
The acquisition contract also included a comprehensive logistics package, accounting for 7.5 percent of the order volume. The package includes adequate and prompt spare parts supply, documentation and training. Also included was a computer-based "Naval Logistic Management System" that controls the on-board maintenance planning and execution by automatically generating weekly check-lists and repair schedules.
Replenishment at sea can take place over the bow, over the stern, or amidship. Liquid and dry goods as well as passengers weighing up to 250 kilograms can be transferred this way. Vertical replenishment via helicopters can take place over the helideck and/or the foredeck.
Kamerman said that these ships were designed to "take punishment" and that they were designed for inherent growth. They have spaces with all the necessary fittings for rapid fitting of additional equipment without needing modifications. This means that the frigates could increase their surface-to-air missile capabilities from 16 launch cells up to 32 launch cells in a relatively few hours. It is expected that this class of frigates will be substantially upgraded over the warships’ 30 to 40 year operational lifetimes. Kamerman has said that the ships had plenty of space to accommodate new equipment and new weapons, and that they were designed to allow for easy removal of outdated equipment through readily-accessible hatches.
Read more about this topic: Valour Class Frigate
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