Guided-Missile Frigate

Overview

A guided-missile frigate is the workhorse surface combatant of most navies: around 7,000 tonnes and 150 m, sized to escort task groups, hunt submarines and defend itself against aircraft and missiles. Naval shipbuilders put a modern frigate at roughly one million individual parts, erected from about 60 pre-outfitted hull blocks. The count behaves the way it does on every large welded structure: a handful of big machines sit on top of vast populations of small hardware. Each Hull Block alone carries about 7,400 Weld Stud & Joint Fasteners and joint fasteners plus 1,800 Structural Brackets, so the hull contributes well over half the total before a single weapon is fitted.

Hull and construction

The Hull Structure is all-welded shipbuilding steel, AH36 Hull Steel Plate from 5 to 25 mm over bulb-flat Hull Stiffeners, with topsides angled for radar signature reduction. Blocks of 80 to 300 tonnes are outfitted in the shop with Pipe Hangers, cable runs and Insulation Panels before erection, then welded together on the slipway or in dock; build time from first steel cut to delivery runs four to six years. The hull subdivides behind some 250 Watertight Doors, designed to survive flooding of any two adjacent compartments. Twin Rudders and active Fin Stabilizers keep the ship steady enough for helicopter operations, and a GRP Sonar Dome at the bow fairs the hull-mounted sonar.

Propulsion

The CODAG Propulsion Plant plant is a CODAG arrangement, combined diesel and gas. Two Cruise Diesel Engines of about 6 MW each drive the ship at economical cruise; for sprint speeds above 26 knots the ~30 MW Boost Gas Turbine clutches in through the cross-connect Main Gearbox. The turbine is an aeroderivative machine of roughly 2,500 rotating aerofoils, 1,500 Turbine Blades in the hot section running near 1,300 °C and 1,000 Compressor Blades ahead of them, held together by a ~9,000-piece Engine Fastener set. The diesels are resilient-mounted 20-cylinder machines, each with a forged Crankshaft, twenty Diesel Pistons and common-rail Fuel Injectors working at ~1,800 bar. Both shafts end in five-blade Controllable-Pitch Propellers whose hub servos vary blade pitch, so fixed-speed engines can drive any ship speed and even reverse without a reversing gear. Underwater radiated noise drives much of the machinery design: the diesels sit on double-stage resilient mounts, the gearbox meshes are precision-ground, and six Coolant Pumps and their pipework are decoupled from the hull to keep the ship quiet enough to hunt submarines with its own sonar.

Sensors and combat system

The Integrated Radar Mast concentrates the topside sensors in one enclosed structure clad in frequency-selective panels. Its four fixed AESA Radar Array faces each carry about 4,000 gallium-nitride Radar T/R Modules, giving uninterrupted 360° air and surface search with no rotating antenna; thirty ESM Antennas and forty Comms Antennas share the mast, all tied down by a ~16,000-piece Mast Fastener population. A rotating Surface-Search Radar above the bridge handles surface contacts and navigation, while the Sonar Suite hunts submarines with a bow Hull-Mounted Sonar Array of 800 piezoceramic Sonar Transducer Staves and a stern-streamed Towed-Array Sonar carrying 256 Hydrophones clear of the wake. Below decks, the Combat Management System system fuses every sensor into one tactical picture across eighteen CMS Consoles backed by six shock-mounted Combat System Server Cabinets, and controls the weapons: the 76 mm Naval Gun (76 mm, up to 120 rounds/min) with its auto-frettaged Gun Barrel and revolving Ammunition Feed, a radar-directed Close-In Weapon System whose Rotary Cannon is the last-ditch defence against sea-skimmers, twin triple Torpedo Tube Set sets that air-eject lightweight torpedoes, and four Decoy Launchers.

Vertical launching system

The Vertical Launching System forward of the bridge holds 32 missiles in below-deck cells arranged as 8-cell modules. Each VLS Cell contains a sealed VLS Canister holding one Guided Missile (a solid Rocket Motor, a terminal Missile Seeker, a Guidance Section and a Warhead), an armoured Cell Hatch, and a gas-management path venting the rocket efflux up through a shared plenum, a hot-launch design that needs no ejection charge. A Thrust-Vector Unit unit tips each missile over toward its target in the first moments after vertical launch. The mechanical detail is easy to underestimate: canister guide rails, hatch mechanisms and module bolting add up to roughly 2,000 VLS Cell Fasteners per cell, about 64,000 pieces for the battery.

Aviation

The Helicopter Facility aft operates one 10-tonne maritime helicopter. A Traversing System captures the aircraft on deck, hauls it down against the probe and traverses it into the hangar behind a roller-shutter Hangar Door, the equipment that makes recovery possible at sea state 5 and above. Six hundred flush Tie-Down Sockets and 8,000 deck-track Weld Stud & Joint Fasteners populate the flight deck plating.

Electrical plant and habitability

The Electrical System runs about 400 km of cable in 8,000 Cable Runs, supported every 60 cm by some 180,000 Cable Hangers and terminated in 55,000 Connectors, after hull fasteners, the biggest hardware population aboard. Four Diesel Generator Sets, each a high-speed Generator Diesel Engine direct-coupled to a brushless Marine Alternator, feed eight zonal Switchboards built from Circuit Breakers and copper Busbars, with two dozen Distribution Transformers stepping down to lighting and electronics supplies, so that battle damage to one zone leaves the rest powered. The Crew Accommodation outfit supports about 120 core crew and up to 180 with flight and mission detachments: 220 Berthing Module modules in small cabins, 90 Head Fixtures, and 700 HVAC Terminals fed through citadel filtration for operations in contaminated environments.