NationStates | Dispatch | MK 60 Series Vortice Multi-Role Torpedo

Dispatch → Account → Military

by The Unitary Technocracy of Etoile Arcture. 1 year 305 days ago. 57 reads.

MK 60 Series Vortice Multi-Role Torpedo

This page is a work in progress by its author and should not be considered final.

MK 61 Mod 0 Vortice Heavyweight Torpedo


Type	Heavyweight torpedo
Place of origin	Etoile Arcture

Service history
In service	2015 - present
Used by	See Operators

Production history
Designer(s)	Sequoia Dynamics
Designed	2003-2014
Manufacturer(s)	Sequoia Dynamics Armament and Technical Products
Unit cost	US$2.5 million
Number built	classified
Variants	See below

Specifications
Mass	1,360 kg (2,998 lb)
Length	6.4 m (21 ft
Diameter	533 mm (21 in)
Warhead	tandem high explosive and shaped-charge
Warhead weight	295.5 kg (651 lb)
Detonation mechanism	proximity or impact

Engine	pump jet propulsor direct-drive brushless motor
Propellant	aluminium silver-oxide battery
Speed	29 kn (54 km/h) to 80 kn (148 km/h)
Operational range	>50 km (max speed) >100 km (min speed)
Maximum depth	>15,500 m
Guidance system	inertial, command wire, active-passive acoustic /wake homing
Launch platform(s)	Submarine

MK 61 Mod 0 Vortice Heavyweight Torpedo measuring 21"/21'

Contents

MK 62 Mod 0 Vortice Lightweight Torpedo


Type	Lightweight torpedo
Place of origin	Etoile Arcture

Service history
In service	2015 - present
Used by	See Operators

Production history
Designer(s)	Sequoia Dynamics
Designed	2003-2014
Manufacturer(s)	Sequoia Dynamics Armament and Technical Products
Unit cost	US$2 million
Number built	classified
Variants	See below

Specifications
Mass	317.5 kg (700 lb)
Length	3 m (9 ft 10⅛ in)
Diameter	324 mm (12¾ in)
Warhead	shaped-charge
Warhead weight	45.36 kg (100 lb)
Detonation mechanism	proximity or impact

Engine	pump jet propulsor direct-drive brushless motor
Propellant	aluminium silver-oxide battery
Speed	18 kn (33 km/h) to 55 kn (101 km/h)
Operational range	>29 km (max speed) >90 km (min speed)
Maximum depth	800-1,100 m
Guidance system	inertial, active-passive acoustic/wake homing
Launch platform(s)	Ship, submarine, aircraft

The MK 60 Series Vortice Multi-Role Torpedo (export designation: Mehrzweck-Torpedo Wirbel or Torpille multi-rôle Vortex) comprises a series of modern fifth-generation fire-and-forget or wire-guided all-up-round (AUR) multi-purpose anti-surface-ship, anti-submarine and anti-torpedo torpedoes of various calibres that share the following design features: a hydrodynamic shape optimised for low drag, high manoeuvrability and long endurance; digital solid-state electronics to enable high tracking and aimpoint accuracy; quiet and efficient electric propulsion plant of low detectability and long-range; and shaped-charge or tandem combined effects (high blast and shaped-charge) warhead with double-hull penetration capability. It comprises a two-model family of the 533 mm (21") calibre MK 61 Mod 0 Vortice Heavyweight Torpedo (HWT) launched from torpedo tubes by swim out or water impulse method, and is also the basis for an unmanned underwater vehicle (UUV); and the 324 mm (12.75") calibre MK 62 Mod 0 Vortice Lightweight Torpedo (LWT) that can be launched from rotary- and fixed-wing aircraft, over-the-side (OTS) from triple-tube launchers on surface ships, fitted with a high altitude wing kit (HAWK) for increased stand-off range, integrated into an anti-submarine rocket (ASROC) system, and encapsulated torpedo (CAPTOR) moored influence mine to deny ship and submarine traffic at choke points.
Both models are equipped with a multimode, multibeam active-passive acoustic homing seeker adaptable towards numerous threats and environments, including countering high-performance surface ships operating in open ocean, littoral or coastal areas; fast, deep-diving, anechoically-coated submarines deploying countermeasures and effectors; and slow, quiet, deep, shallow-water or bottomed-out submarines and mini-submarines. Vortice torpedoes can operate with mixed-mode guidance depending on the tactics chosen, either using wire command guidance from the launch submarine (heavyweight torpedoes only), and on termination of the guidance wire or when launched free-running autonomously execute programmed target search, acquisition and attack procedures. It is capable of searching for a target with a preset series of programmable search patterns (snake (sinuous), spiral or helical) and of performing tactical manoeuvres (sprint and drift, off-axis approach), and navigating along programmed waypoints to a preset acoustic enabling distance where it will search for and home on a target by active and passive acoustic homing or active wake homing.

General description

The hull of a Vortice torpedo has a length/diameter (L/D) ratio between 1:12 (heavyweight torpedo) and 1:9.25 (lightweight torpedo) that maximises internal volume for greater efficiency of the propulsion plant, propellant, warhead and sensor array. It has a large wetted surface area for increased hydrodynamic performance and manoeuvrability with a NACA lamina flow forebody shape, long cylinder constant diameter mid-section, roll stabilisation fins, and teardrop-shaped tapered afterbody section and pumpjet shroud. The hull is constructed from lightweight 7085 aluminium alloy forgings and castings with a smooth sand-blasted exterior surface that reduces flow resistance for minimisation of cavitation noise and drag for enhanced propulsive efficiency. A heat-curable fusion-bonded epoxy powder (FBE) thermoset polymer coating protects the exterior from salt spray and seawater corrosion. The dome-shaped torpedo bow is separately constructed from bandpass resonate carbon fibre reinforced plastic (CFRP) that provides a sonar transparent window for the seeker. The torpedo is divided into five compartments:

The homing section with active/passive acoustic seeker based on multi-frequency conformal hydrophone arrays;
The warhead section consisting a shaped-charge on the lightweight torpedo and tandem combined effects warhead on the heavyweight torpedo (exchanged for an inert ballasted dummy warhead on exercise torpedoes);
The guidance and control (G&C) section with solid-state digital mission computers, signal processors and communication and navigation electronics;
The battery section with seawater-activated aluminium silver-oxide electrochemical stack primary battery system;
The propulsion section with very low noise footprint integrated motor propulsor (IMP) built into a shroud at the end of a tapered afterbody.

Design details

Homing section

The active/passive acoustic seeker can search, detect, track, classify, localize, target, home, and prosecute threat targets. It contains an array of wideband piezo composite electro-acoustic transducers that outwardly resemble tiny rods or pegs, with 256 on the heavyweight torpedo and 128 on the lightweight torpedo. The arrays are geometrically arranged in a three-dimensional antenna pattern along the curved contour of the paraboloid-shaped bow combining transmission transducers in a narrow flat vertical zone, reception transducers in a wide round horizontal zone and dual-function transducers in a spiral arrangement, allowing for wide sensor gaze angles to acquire and track manoeuvring targets. The backend sonar system consists of a transmitter, digital transmit beam-former, sonar controller, waveform generator, digital filter, and receive beam-former. These produce multiple multi-frequency, independently-steerable, preformed narrow transmit and receive beams with combined narrowband (CW) and broadband (FM) transmission pulses of different durations in six frequency bands with a bandwidth of >10 kHz. Passive medium frequency beams are used for long-range target acquisition, upward-pointing active high-frequency beams to detect motion in the water (wake homing) and downward-pointing echo-sounding for navigation, and high gain performance with simultaneous multi-frequency active and passive beams to detect low-Doppler, low silhouette and silenced (anechoically coated) targets, discriminate spatially between target noise, acoustic countermeasures and reverberations, and for tracking multiple targets. The maximum unambiguous angular search range is a ±120° horizontal by ±70° vertical panoramic field-of-view with a maximum active target acquisition range of 1.1 to 2.5 km depending on local sea conditions.

Warhead section

The lightweight torpedo is equipped with a 45.36 kg (100 lb) directed energy (shaped-charge) warhead while the heavyweight torpedo employs a larger 295.5 kg (651 lb) high energy/high blast combined effects tandem warhead with a forward focused high-explosive blast and rear annular linear shaped-charge as the two stages. Both warheads contain a low sensitivity PAX-42 cast aluminised insensitive high explosive filler, with the kill mechanism in both cases the directed energy from a focused jet of molten metal to penetrate submarine pressure hulls, surface ship double-hulls, and breach intercompartmental bulkheads. Target destruction is by a single direct hit either by detonating under the keel to break the back of a surface ship or through hull penetration. The high-explosive precursor in the tandem warhead has a very high metal pushing/acceleration (Gurney energy) that generates isotropic blast effects that compromise structural integrity to aid hull perforation. A solid-state all-electronic fuze with impact/graze and multi-frequency acoustic proximity exploder allowing stand-off detonation for an under-the-keel explosion, with the trigger mechanism a low energy exploding foil initiator (LEEFI) or slapper detonator insensitive to shock, vibration, temperature and electromagnetic interference.

Guidance and control section

the mission computer has basic control of position, speed, heading, pitch and depth, and selects the tactics used when free-running. Guidance inputs include active acoustic homing (echo-location ranging) and acoustic wake following (cavitation of ship/submarine propeller) using multi-frequency FM and CW pulses, multiple pre-formed beams for passive acoustic bearing estimation, a strap-down dual-axis inertial navigation system with solid-state sensors (dual accelerometers and a single axis rate gyroscope), and fibre-optic cable (wire-guided) command guidance. Guidance and control (G&C), autopilot, weapon control, power control, data collection and signal processing functions are performed by modular upgradeable open architecture ruggedized commercial-off-the-shelf (RCOTS) semiconductor components. These use complementary metal-oxide-semiconductor (CMOS) integrated circuits hardened against ionising radiation, de-rated for reliable operation in extreme thermal conditions between -40°C to +85°C (deep ocean temperatures range from 0°C to +3°C), and provide vibration and shock resistance to survive accelerations/decelerations up to 100 g (980 m/s²). Search, classification and homing is performed by RCOTS high throughput parallel processing broadband signal processor and guidance and control using inertial reference data and proportional navigation rules by redundant primary and backup tactical data processors.
To fit within the restricted volume of the torpedo casing the mission computer is based on compact PC/104+ form-factor (90 x 96 mm) ruggedized low-profile self-stacking PCI card electronics modules that are drop-in replaceable for future expandability and upgradability. The modules are stacked with ISA pin-and-socket bus connectors that are positively locked by four-corner mounting holes inside a rugged aluminium alloy enclosure. The stacked configuration consists of a command and control processor module and a tactical processor module that controls the autopilot, each powered by a 450 MHz (de-rated to 300 MHz) PowerPC 405A embedded dual-core 32-bit superscalar processor; four floating-point digital signal processor (DSP) modules each with quad ADSP-21060/62 Super Harvard Architecture Computer (SHARC) 32-bit processors capable of 120 MFLOPS peak and 80 MFLOPS sustained compute performance at 40 MHz, cross-connected to low-pass filtered 16-channel 16-bit analogue-to-digital (A/D) converters.
The heavyweight torpedo adds a RS-422/485 multi-interface communication module with bi-directional high-speed serial and fibre-optic interconnects. It functions with a fibre-optic wire guidance system consisting of a guidance wire reel on both the torpedo and launch platform that payout simultaneously to minimise stress on the wire, and a 25,000-metre spool of 0.75 mm diameter Kevlar-reinforced polyamide cable with a monomodal inner 300µm optical glass fibre. The large bore of the multimode optical cable allows for multiple pathways and wavelengths of light to maximise throughput with a bi-directional full-duplex performance of 10 megabits per second that carries up to sixteen 16-bit sonar channels, operating data including torpedo health and four command data channels. It enables the torpedo to receive mid-course guidance updates including manual course and speed corrections and depth changes using ownship and/or torpedo active or passive acoustic homing data for guidance. Tight turns and high speeds by the torpedo or an emergency guillotine on the firing submarine can sever the guidance cable, with a free-running torpedo programmed to continue in autonomous self-guiding mode, including conduct multiple re-attacks if missing the target and circling around to re-acquire if losing contact.

Battery section

The stored energy system is a lightweight, quiet, high volume efficient, high energy density, seawater-activated, single-use electrochemical stack primary battery. The voltaic pile is built from aluminium silver-oxide (AgO-Al) reserve primary cells that consist of an aluminium alloyed anode (negative plate) and silver-oxide alloyed cathode (positive plate) secured inside an impact- and shock-resistant polypropylene casing. The batteries generate high voltage electricity from the reaction of non-toxic chemicals as they are dissolved by an alkaline electrolyte (i.e., seawater) introduced post-launch by a water scoop. The current is converted by a solid-state power regulator to match the load to the onboard electronics, seeker, and variable speed integrated motor propulsor (IMP) that propels the weapon. The battery operates at a 105°C peak temperature inside a closed-loop electrolyte cooling recirculation system comprised of an electrolyte mixer, heat exchanger, recirculation pump and gas separator. This system produces highly efficient performance by ionic exchange between cathode and anode fully independent of depth, temperature, salinity or other environmental factors, operating nearly silently and at a very high specific energy. A carefully controlled flow of seawater through the battery removes heat sludge and hydrogen gas, while electrolyte recirculation offsets the effects of cold water or lack of salinity. It has double the performance of other seawater-activated batteries and produces a 100% power output for 180 minutes that reduces to 80% after about 160 minutes. The heavyweight torpedo utilises four expendable battery modules and the lightweight torpedo a single module which can be replaced after use to allow reliable and cost-effective reuse of inert exercise torpedos.

Propulsion section

The integrated motor propulsor (IMP) is directly integrated into the fixed ducted shroud of the pumpjet propulsor for high volume and weight efficiency. It consists of an external radial-field, rim-driven, axial-flow high-frequency permanent magnet (PM) brushless DC motor operating at 97.5% efficiency, coupled by low-friction bearings to twin contra-rotating 13-blade (strator) and 10-blade (rotor) carbon-fibre skewed propellers. The unit produces high thrust by the wakeless pumpjet effect without cavitation and with extremely low levels of self-generated radiated noise. Directional control is provided by dynamically altering the angle-of-attack (AoA) of the stator blades within the propeller inflow to produce vectored thrust at ±15° pitch angles, enabling the torpedo to rotate ±90° on its axis to acquire, track and attack targets. The IMP is capable of variable runout speeds in 1-knot increments across the speed envelope and can throttle from minimum to maximum power in under 3 seconds. The torpedo is capable of an initial slow, quiet, stealth approach that minimises the alert distance of submarine detection systems, performs rapid course and speed changes (sprint and drift) to track manoeuvring targets while retaining sufficient speed and range performance to overhaul an escaping target in the end game. operating power differs between models with 163.155 PS (120 kW) generated on the lightweight torpedo and 407.88 PS (300 kW) generated on the heavyweight torpedo.

Weapon conversion kits

The MK 62 Mod 0 Vortice Lightweight Torpedo can be modified for aerial delivery from a 300 m (~1,000 ft) aircraft release altitude using a ballute decleration and stabilisation system inflated by a gas generator attached to the rear of the weapon; or by attaching a High Altitude Wing Kit (HAWK) for stand-off release from a 500-9,200 m (~1,640-30,000 ft) altitude to a range of 10-15 km (5.4-8.1 nmi). The weapon will glide in a controlled descent to a precise water impact point near the predicted position of the target enabling an aircraft to engage hostile submarines outisde the envelope of defensive submarine-launched anti-aircraft missiles. The HAWK includes folding wings, control surfaces, digital flight control computer, battery and strapdown inertial (GPS/INS) guidance and navigation system. It can be carried as a bomb bay or wing pylon store by the P-21A Coriolis maritime patrol aircraft. For increased attack and kill probability a dipping sonar or pre-laid sonobuoy field can localise the target for easier acquisition and tracking by the torpedo acoustic seeker.

Operators

Etoile Arcture