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Mar 20 15 3:19 PM
BSmittyVA wrote:Matt, 1) MCL Stabilization:a) I worry that "successful ATACMS launch" and "operational capability" are two different things. Presumably the test launch was in favorable seas. I imagine a modest degree of stabilization wouldn't be that difficult. The Israelis built a stabilized version of their LAR-160 launcher for a naval project a while back.2) You can gain volume by aggregating ships. There are far more US shipyards capable of building FSVs or OSVs than aluminum wave-piercing cats. If you can buy two or three FSVs vs one 84m Cat, you can have as many or more MCLs on station. Damen has larger Sea Axe designs in their Yacht Support Vessel line. Here's a 67m Sea Axe with a helo pad. Note the deck is raised a level. http://www.yacht-support.nl/fileadmin/files/Content/Yacht-Support/Range/6711-dive/6711-dive.pdfYou could either stow reloads below, or have additional accommodations, or both. On speed, I really don't see the need for much more than 25kts. IMHO, it needs to be able to keep up with an amphibious task force. The UAE contracted with Damen to produce two rather heavily armed OPVs based on the 6711 design. http://www.janes.com/article/36192/details-of-new-uae-coast-guard-vessels-emerge CICPA has specified a comprehensive weapon, sensor and command suite, for which Thales Nederland is taking major responsibility. As well as supplying its TACTICOS combat management system, SMART-S Mk 2 E/F-band surveillance radar, Mirador electro-optical (EO) system, STIR 1.2 EO Mk 2 radar/EO fire control director, Vigile radar-band electronic support measures (ESM) and Altesse communications ESM, Thales is also taking overall responsibility for combat system integration. The Arialah ships will each be armed with an OTO Melara 76/62 gun forward, two OTO Melara MARLIN 30mm gun mountings on either beam, and a single Raytheon Mk 49 Mod 2 11-cell Rolling Airframe Missile launcher amidships. Rheinmetall MASS decoy launchers will be fitted for soft-kill protection. CICPA's Arialah vessels will be fitted with a helicopter flight deck aft.
CICPA has specified a comprehensive weapon, sensor and command suite, for which Thales Nederland is taking major responsibility. As well as supplying its TACTICOS combat management system, SMART-S Mk 2 E/F-band surveillance radar, Mirador electro-optical (EO) system, STIR 1.2 EO Mk 2 radar/EO fire control director, Vigile radar-band electronic support measures (ESM) and Altesse communications ESM, Thales is also taking overall responsibility for combat system integration. The Arialah ships will each be armed with an OTO Melara 76/62 gun forward, two OTO Melara MARLIN 30mm gun mountings on either beam, and a single Raytheon Mk 49 Mod 2 11-cell Rolling Airframe Missile launcher amidships. Rheinmetall MASS decoy launchers will be fitted for soft-kill protection. CICPA's Arialah vessels will be fitted with a helicopter flight deck aft.
The US Navy also tested one such round at White Sands, followed by an at-sea launch from the amphibious assault ship USS Mount Vernon in February 1995. The vessel, steaming at 10kt, fired the missile from a standard M270 tracked launcher chained to its helicopter deck (emphasis added)... An operational variant of Navy TACMS could use either the Mk41 Vertical Launch System (for which United Defense has designed a suitable canister) or fixed deck launchers. The round's six-channel GPS receiver provided 13 position updates, using a total of eight Navstar satellites, during its 75nmi flight to the target area on San Clemente Island off the coast of California. The missile then dispensed some 800 inert grenades, achieving an accuracy of 71% of the weapon's nominal circular error probable (emphasis added).
12 February 95 : The final NATACMS Block IA prototype missile test was an "at sea" firing from an M270 launcher on the deck of the USS Mount Vernon positioned off the coast of San Diego, California. The shot flew 75 nautical miles for a direct hit on the target (emphasis added).
Mar 20 15 4:05 PM
Mar 20 15 4:57 PM
BSmittyVA wrote:1) Presumably they concluded stabilization was not needed for ATACMS, which probably can compensate a fair bit, but that doesn't necessarily apply to GMLRS, with its tiny, movable fins. Also, as you said, firing from an LSD and firing from one of these small platforms are two different things. 2) Ideally an ASOTC could fire both GMLRS and ATACMS in moderate sea states. One of the selling points of NSFS is that it is "all weather". 3) Even further, it would be nice if ASOTC could fire smaller guided rockets like ACCULAR or the old LockMart P44.http://defense-update.com/products/p/P44.htm
Mar 20 15 5:09 PM
BSmittyVA wrote:Edit 1: Adapting the technology developed for Active Heave Compensated Cranes for MCL stabilization should be relatively straight forward. http://gcaptain.com/watch-macgregors-3-axis-motion-compensated-crane-aboard-siem-moxie/Edit 2: I provide the rough costs for a 6711-based Yacht Support Vessel earlier (~$32 million). Presumably an OSV would be cheaper because it doesn't need to have the "luxury" appointments. However at this point, perhaps cost is a moot point. The systems added for the ASTOC will dominate the price of the vessel. So other factors would determine the selection, such as required speed, seakeeping, range, payload, accommodations, damage tolerance, etc.
Mar 20 15 5:24 PM
Mar 20 15 7:45 PM
Mar 20 15 8:38 PM
BSmittyVA wrote:Here's a list of recent PSV and crewboat purchases with prices. http://www.palgrave-journals.com/mel/journal/v15/n2/fig_tab/mel20134t7.htmlBuyerVessel typeLength (ft)NumberTotal gross tonnage (GT)Total cost (million$)Cost per vessel (million$)Cost per gross ton ($/GT)Contract yearInflated cost per gross ton ($/GT)HornbeckPSV240–2901632 66044527.813 625200615 217TidewaterPSV250243666532.514 888200716 019TidewaterPSV2503654952.517.5801620059280TidewaterPSV2202262626.813.510 206200511 816GulfmarkPSV2453614276.525.512 455200713 401Harvey GulfPSV240–280611 6532003317 163200619 169Harvey GulfPSV292621 26020033940720109407RigdonPSV1901016 03212012748520068360TricoPSV210234163517.510 246200611 443L&M Bo TrucPSV23023502502514 278200814 926SeacorPSV217112431010804520039999AVERAGE—————24.411 776—12 640TidewaterCrew17514946.86.813 765200515 936TidewaterCrew17514947.27.214 574200616 278TidewaterCrew1754197625.56.412 904200117 133GulfmarkCrew180299618.49.218 473200819 313SeacorCrewa170149814.714.729 518200930 021AVERAGE—————8.414 929—17 165Most are fairly cheap. The 210ft Trico PSV is close in size to the 6711, though it's only a 15kt vessel. It was $17.5 million and built at Bender Shipbuilding in Mobile, Alabama. The 217 foot Seacor Pride was built in 2003 at VT Halter for $10 million.
Mar 20 15 8:45 PM
BSmittyVA wrote:I wonder if the Sea Axe bow would preclude adding a MOAS or small ASW sonar like Thales BlueWatcher?
Thales Underwater Systems Signs Contract for Mine and Obstacle Avoidance Sonar(Source: Thales Underwater Systems; issued Dec. 3, 2003)RYDALMERE, Australia --- Sydney-based Thales Underwater Systems Pty Limited has signed a A$21M contract with Tenix Defence Pty Limited on behalf of the ANZAC Ship Alliance, to supply eight Petrel mine and obstacle avoidance sonar systems for the Royal Australian Navy’s ANZAC Class frigates.The Petrel mine and obstacle avoidance sonars will further enhance the self-protection capability for Australia’s new fleet of ANZAC frigates.The Petrel mine and obstacle avoidance sonars detect mines and navigational hazards in sufficient time for ships to avoid them. Senator Robert Hill, Minister for Defence, when announcing the approval of the project in the Federal Government’s 2003 May Budget, said “This is an important capability in operations where there is a mine threat, such as in the waterways around Iraq, as well as in the shallow, poorly charted waters that are prevalent throughout our own region.”The Petrel mine and obstacle avoidance sonar has been developed by Thales Underwater Systems in Australia for the Department of Defence and is the first of its type of sonar system in the world. This unique sonar provides a 3-dimensional picture of the ocean ahead of a ship including the sea floor and obstacles in the water column such as mines and other threats to safe navigation. The system can also be used while ships are at berth to detect divers thereby providing a self-defence capability against terrorist threats.Petrel mine and obstacle avoidance sonars are also currently being supplied to the Royal Australian Navy’s FFG Upgrade Project as part of Thales Underwater Systems underwater warfare system.
Mar 20 15 9:11 PM
Mar 21 15 8:03 PM
Mar 25 15 12:17 AM
Apr 20 15 11:26 PM
rdfox wrote:Speed capability is *way* overkill for a ship intended for NSFS. It would almost certainly be kept tied to an ARG, meaning it should travel at the same sort of speeds as the existing 'phibs--24 knots or so.
Apr 27 15 1:48 AM
Apr 27 15 11:21 PM
Apr 28 15 4:50 PM
Apr 29 15 8:11 PM
Scott Brim wrote:If the ship is continuously on patrol waiting to fire its missiles -- some day, for some reason, in some kind of future conflict -- what other kinds of missions and roles does it handle, if any? In other words, are these ships always present somewhere doing something; and if so where, doing what?
May 1 15 10:57 PM
BSmittyVA wrote:Yes, BlueWatcher is overkill for an ASOTC, but in the back of my head I'm considering a small, inexpensive, multi-mission vessel that can accept different modules (e.g. ASOTC, ASW module, ASuW, MIW, MIO). BlueWatcher might be handy for the base seaframe. Of course this line of thinking can send one down the feature creep path. (e.g. electric drive and other sound reduction features) For a dedicated ASOTC, an M&OAS sounds more appropriate.
May 2 15 6:31 PM
BSmittyVA wrote:However having munition variety would help in cases where 25+nm isn't required. Suppressing near shore artillery/mortar/ATGM positions during an amphibious landing, is one use. A rocket based "Five Inch Friday" is another.[...]ACCULAR has effects closer to that of a 155mm round, which could be valuable for area fires. 13 ACCULAR can fit in a pod the size of a standard 6-rnd MLRS pod. In theory, ACCULAR could be cheaper than GMLRS, but hard to know for sure.The combination of stabilization and the IMI Trajectory Correction System could allow the ASOTC to fire cheap, unguided rockets with near guided precision. TCS-controlled LAR-160 rockets with HE warheads sound good for area fires, considering the desire to move away from ICM.
IAI Presents Strikes – 122mm Precision RocketJune 14, 2010Haifa, Israel: Israel Aerospace Industries (IAI) will unveil a series of effective and affordable weapon systems at this year's Eurosatory Symposium and Exhibition in Paris.These systems share the common vision of affordability and precision, transforming "statistical" artillery into precision weapons.IAI's vision of future weapon systems stresses the ability to create highly precise systems that enable the support fire elements to do their jobs faster, more accurately and with much less collateral damage.IAI is presenting the "Strikes", a 122 mm Precision Rocket which can hit targets with a very high rate of precision. Strikes is composed of a 122 mm rocket and a guidance kit, which is installed between the head of the rocket and the motor.Once the rocket has been fired, the motor is disconnected, and the rocket head with the guidance kit continue towards the target, utilizing a GPS which operates the four steering fins.Zvi Top, head of the Precision Strike Systems Directorate in the MLM Division of IAI's Systems, Missiles, and Space Group, said: "From the beginning, 122 mm rockets were used as precision artillery. Strikes has a much greater precision capability than the regular 122 rocket, which helps avoid potential damage of the surrounding area. The inexpensive price of this upgrade provides IAI with a new, promising business line."
STRIKESSTRIKES - Guided 122 mm Rocket. STRIKES- Affordable Precision:* STRIKES upgrades existing 122 mm rockets for optimal accuracy* STRIKES is based upon an add-on guidance kitSTRIKES - A Breakthrough in Cost-Effectiveness:* STRIKES preserves the original range of the 122 mm rocket up to 40 km* STRIKES breaks the linkage between range and accuracy. Accuracy is now better than 10 m CEP at any rage* STRIKES minimizes collateral damage* STRIKES fits known 122 mm launchers with minimal changes to the launcher* Fewer rockets per fire mission* Shorter logistic tail
3) In such specific environments, some reasons for choosing IAI's STRIKES rather than IMI's ACCULAR would be :* STRIKES with its 40-45lb warhead (about 10lb HE-FRAG unitary payload) should be good enough for suppressing near shore artillery/mortar/ATGM positions;* STRIKES offers the same range as ACCULAR (about 40 km);* STRIKES should be less expensive than ACCULAR (given the number of sources producing 122mm rockets);* STRIKES has 20 rockets per pod, i.e. almost twice as many as ACCULAR (11 rockets per pod); each ASOTC would therefore carry up to 480 x 122mm guided rockets.
May 2 15 8:36 PM
On the ASOTC, the Seahawk SIGMA would be armed with Mistral missiles, thereby eliminating the need for the dedicated VSHORAD missile launchers initially envisioned.The most appropriate spots for the Seahawk SIGMA would seem to be on the edge of the bridge wings, which would offer firing arcs in excess of 180° for each mount, thereby providing an overall 360° gun & missile coverage.This substitution would offer the following benefits :* more efficient use of available deck space* more ready-to-use VSHORAD missiles for improved AA self-defense* increased firepower (the 30mm x 173 ammunition used by the Mk44 Bushmaster is more powerful than 30mm x 113 ammunition used by the M230LF)* better commonality with the rest of the fleet (the Mk44 Bushmaster already in service on San Antonio and LCS classes) and wider choice of ammunitionsThis substitution is not anticipated to have a significant impact on the ASOTC in terms of affordability and might even result in savings in terms of acquisition & lifecycle costs.NB : the Mark-60 Griffin Missile Systems initially envisioned would be retained in the new configuration, with (a least) two launchers (P/S) with 4 missiles each.2) Sensors (see this post)The Thales NS100 radar (see here and here) would replace the SAAB Sea Giraffe 1X and Kelvin Hughes SahrpEye radars initially envisioned for the ASOTC.The Thales NS100 is a multi-sensor solution integrating :* an S-band AESA 3D radar with dual-axis multi-beam processing;* an IFF interrogator & transponder;* an X-band Scout Mk3 FMCW antenna;* an IR camera* AIS & ADS-B antennas & receiverPositioning all sensors on one platform at the best topside position is expected to :* facilitate a higher level of integration;* optimize the overall field of view;* minimize footprint & interference issuesThe S-band AESA 3D radar also offers improved operational performance over the X-band AESA 3D radar initially envisioned (200km instumented range for the former vs 100km instrumented range for the latter).With a unit cost of about EUR 6.5 million (i.e. USD 5.8 million based on current exchange rates), this substitution is not anticipated to have a significant impact on the ASOTC in terms of affordability.NB : the Targeting System envisioned for the ASOTC remains the FLIR BRITE Star II, which is currently being installed on the US Navy Cyclone-class PCs to provide laser designation for the Griffin missiles.
May 2 15 11:17 PM
As stated earlier, the Arsenal Ship On The Cheap (ASOTC) is NOT intended to morph into the Littoral Combat Ship On The Cheap (LCSOTC). As a result, any kind of small ASW hull-mounted sonar (e.g.Thales Bluewatcher) is a NO-GO for the ASOTC. Some kind of Mine & Obstacle Avoidance Sonar (M&OAS) might nevertheless prove useful, but it's not clear how much redesign traditional (retractable) M&OAS would imply and how interference with the retractable azimuth thruster could be avoided. The following document presents a brief background to the technical issues associated with high-speed vessel strikes on cetaceans :Active Sonar For Marine Mammal Risk Mitigation With High Speed Vessel OperationsFor instance, for a vessel that might operate at speeds as high as 40 knots, system deployment and the mechanical forces imparted to the array by the induced drag seem to exclude traditional retractable M&OAS as a convenient solution.NB : The paper makes it clear that the radiated noise from a high-speed vessel is predominantly generated at the rear of said vessel and that a high degree of noise rejection might be achieved by exploiting the directionality of the beampattern. IOW, on the contrary to some of the fallacies propagated by some milblogs (ID for instance), self-noise is NOT the reason why the M&OAS was dropped from both LCS designs.
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