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  • Originally posted by DeV View Post
    I agree but it isn't what the WP says
    The WP isn't gospel. It isn't written in stone, it is merely a baseline.

    Comment


    • The two existing Coastal Patrol Vessels, the LÉ Ciara and LÉ Orla, are due for replacement in the coming years. These ships will be replaced with similar vessels with countermine and counter-IED capabilities. This will provide an enhanced capability for the Naval Service in meeting a broad range of ongoing requirements and contingencies, including the protection of Ireland’s vital sea lanes of communication.
      OK, an observation from someone with practically no knowledge of nautical matters -

      This appears to be an aspirational, with the DF gaining a new/new level of capability against mines. Which is excellent.

      But bear with me *dons dunces hat*

      Vessels tasked with mine clearance/hunting seem to be smaller - the German Frankenthals, RN Sandowns are all circa 55M in length.

      I understand the need for larger vessels, but are we going against conventional wisdom by tasking a 80-90M vessel with counter-mine capability?

      If the oft repeated "steel is cheap" argument is correct, why do other nations persist with compact counter-mine vessels, when they could stretch them and double their usefulness on the cheap?

      Not playing devils advocate or anything, just genuinely curious about this and hope to learn more. Thanks!

      Comment


      • Originally posted by pym View Post
        OK, an observation from someone with practically no knowledge of nautical matters -

        This appears to be an aspirational, with the DF gaining a new/new level of capability against mines. Which is excellent.

        But bear with me *dons dunces hat*

        Vessels tasked with mine clearance/hunting seem to be smaller - the German Frankenthals, RN Sandowns are all circa 55M in length.

        I understand the need for larger vessels, but are we going against conventional wisdom by tasking a 80-90M vessel with counter-mine capability?

        If the oft repeated "steel is cheap" argument is correct, why do other nations persist with compact counter-mine vessels, when they could stretch them and double their usefulness on the cheap?

        Not playing devils advocate or anything, just genuinely curious about this and hope to learn more. Thanks!
        *points at dunces cap*...they don't usually build counter-mine vessels out of steel.

        Comment


        • Originally posted by pym View Post
          OK, an observation from someone with practically no knowledge of nautical matters -

          This appears to be an aspirational, with the DF gaining a new/new level of capability against mines. Which is excellent.

          But bear with me *dons dunces hat*

          Vessels tasked with mine clearance/hunting seem to be smaller - the German Frankenthals, RN Sandowns are all circa 55M in length.

          I understand the need for larger vessels, but are we going against conventional wisdom by tasking a 80-90M vessel with counter-mine capability?

          If the oft repeated "steel is cheap" argument is correct, why do other nations persist with compact counter-mine vessels, when they could stretch them and double their usefulness on the cheap?

          Not playing devils advocate or anything, just genuinely curious about this and hope to learn more. Thanks!
          I think the USN had larger ones, the one that ran aground in the Pacific was 1000 tons and just under 70m same for the Japanese hulls, and if the replacements are to be aboutthe same size as the CPV's then that's about it.

          Comment


          • Originally posted by Marius View Post
            *points at dunces cap*...they don't usually build counter-mine vessels out of steel.
            Well the LCS's are meant to be Counter-Mine ships using unmanned and helicopter based systems, think the new Japanese ships are steel as well. Think all the future ones are going with the idea of using stand off systems to do the clearance.

            Comment


            • Originally posted by na grohmití View Post
              The WP isn't gospel. It isn't written in stone, it is merely a baseline.
              The WP is the medium term (10 year) policy framework, it underpins engagement with international organisations, ensures roles relate to requirements, "guide and underpin decisions relating to" the DF and underpin development of capabilities.

              It will guide every DF plans that will be issued in the next 10 years. This one will have a review of the implementation (and any required revisions) every 3 years.

              That may not be the way you see it but it is seen by the DF basically as an order!

              Comment


              • Originally posted by ropebag View Post
                i'd be interested to know, in practice, where a CPV can go that an OPV with its sensors and weapons, including UAV and RIB's, can't.

                i imagine that the list is rather short, and very easily surpassed by the list of things than an OPV can do - and that the has NS needed vessels to do this year - that a CPV can't...
                This is it, The NS will be best served by units which have greatest utility. Same might also apply to IAC .

                Comment


                • Originally posted by Sparky42 View Post
                  Well the LCS's are meant to be Counter-Mine ships using unmanned and helicopter based systems, think the new Japanese ships are steel as well. Think all the future ones are going with the idea of using stand off systems to do the clearance.
                  The aforementioned Frankenthals are steel too - with antimagnetic treatment like subs get.

                  But I take the point, if you can use stand off systems I guess the structure/size of the vessel will be far less important.

                  Comment


                  • CPV Replacements

                    Originally posted by DeV View Post
                    I agree but it isn't what the WP says
                    Looking at the various posts since 15th December. I would comment as follows. The WP is a creature of Government and is subject to a drip and dole financial regime. They are very often used to cap development and reduce expansion of spending by inbuilt restrictions such as Two Brigades and 8 ships.

                    The reason CM ships were built as they were from non-magnetic materials post WW11, was too allow them sweep magnetic mines with some degree of safety. As mines developed into unmoored influenced types, often air droppable, a change was made in mine countermeasures with the introduction of a Clearance Diving approach involving a stand off mothership with detection equipment, a rubber boat with clearance divers on board who were directed to the object. The diver would place a charge near the suspect mine, return to his boat, and detonate the charge remotely. The Sandown type vessels are no longer meeting the perceived needs for quickly dealing with mined areas. The preference now is shifting to unmanned , remotely controlled, unmanned underwater vessels eg UUV types. Such equipments can be launched from most platforms including those built of approved metals designed for Mine Countermeasures. It seems in any event the Sandown type vessel will be replaced by remote technology and should not be on our list. We are in a way too small to diversify into stand alone units, and must stay with a multirole capability. The exception proving the rule is the Diving unit, essential to any Navy but costly to run (Ninth Ship) but could provide a MCM capability from our vessels fitted with the necessary bits and bobs.

                    Comment


                    • Originally posted by ancientmariner View Post
                      Looking at the various posts since 15th December. I would comment as follows. The WP is a creature of Government and is subject to a drip and dole financial regime. They are very often used to cap development and reduce expansion of spending by inbuilt restrictions such as Two Brigades and 8 ships.
                      A lot of those comments are by people who have no idea of level a Defence WP directly impact all DF plans.

                      This WP (IMHO) is trying to be all things to all people which isn't necessarily a bad thing.

                      It also commits to increase defence spending and a minimum of 2 brigades and 8 ships

                      The reason CM ships were built as they were from non-magnetic materials post WW11, was too allow them sweep magnetic mines with some degree of safety. As mines developed into unmoored influenced types, often air droppable, a change was made in mine countermeasures with the introduction of a Clearance Diving approach involving a stand off mothership with detection equipment, a rubber boat with clearance divers on board who were directed to the object. The diver would place a charge near the suspect mine, return to his boat, and detonate the charge remotely. The Sandown type vessels are no longer meeting the perceived needs for quickly dealing with mined areas. The preference now is shifting to unmanned , remotely controlled, unmanned underwater vessels eg UUV types. Such equipments can be launched from most platforms including those built of approved metals designed for Mine Countermeasures. It seems in any event the Sandown type vessel will be replaced by remote technology and should not be on our list. We are in a way too small to diversify into stand alone units, and must stay with a multirole capability. The exception proving the rule is the Diving unit, essential to any Navy but costly to run (Ninth Ship) but could provide a MCM capability from our vessels fitted with the necessary bits and bobs.
                      The NS is to get 2 replacement CPVs with a counter-mine/IED capability. I would agree that the last thing the NS should want is something like a 2nd hand MCMV (eg Sandown class). While they are excellent MCMVs (with the CD and unmanned underwater vehicles as you mention), they are too small to be able to complete the CPV role.

                      So IMHO seeing that the NS is getting direct replacements for the current CPVs (with an additional capability), what they should be looking at is:
                      700-1000 tonne displacement (bigger with improved sea keeping capability)
                      Draught <3 metres
                      Capability to carry 2-3 TEUs (for the additional capability plus a crane for handling ROVs, wet room, additional accommodation etc)
                      Min 2 RHIB on davits
                      Accommodation to a similar standard of the rest of the fleet (which will make it bigger and/or require a smaller crew)
                      Armament 76mm, 20mm's, HMGs, GPMGs
                      14-21 day endurance
                      Max Speed approx 23 kts

                      Options:
                      Constructed with low magnetic signature
                      A larger RHIB for supporting diving ops
                      Specialist counter mine hull mounted/towed sonar
                      Max speed of 25-30 kts


                      Potentially it is a CPV/dive tender or a CPV/MCMV.

                      Realistically most existing designs of MCMVs/CPVs are 600 tonnes or less and would be less capable sea keeping wise than the Peacocks. So the only option may be a bespoken design.
                      Last edited by DeV; 29 December 2015, 20:46.

                      Comment


                      • The solution is already out there, just paint it grey.
                        It's called, surprisingly, a Dive Support ship.
                        http://www.vroon.nl/Files/VesselPart...1210033459.pdf

                        The offshore industry is offloading them by the hundred at present, with the slump in the price of oil. In the short term, you could charter one, see if it works. You have a hull in the water, with equipment long sought but never before available to the NS. If it doesn't work at the end of the charter you hand it back, and go back to the drawing board. but in the meantime you have had that hull in the water.

                        Comment


                        • Originally posted by na grohmití View Post
                          The solution is already out there, just paint it grey.
                          It's called, surprisingly, a Dive Support ship.
                          http://www.vroon.nl/Files/VesselPart...1210033459.pdf

                          The offshore industry is offloading them by the hundred at present, with the slump in the price of oil. In the short term, you could charter one, see if it works. You have a hull in the water, with equipment long sought but never before available to the NS. If it doesn't work at the end of the charter you hand it back, and go back to the drawing board. but in the meantime you have had that hull in the water.
                          As a CPV replacement?

                          As I said (repeatedly) the WP says the CPVs will be replaced by "similar" vessels with "counter-mine / C-IED" capability. That capability could be in 1 of 2 forms (a) a MCMV (b) a CPV with space for a few TEUs etc

                          This could be a 9th vessel but:
                          It has the displacement of an OPV
                          A deeper draught than any vessel in the fleet
                          Cruising speed of 12kts (so potentionally the slowest vessel in the fleet
                          Would have the weakest armament in the fleet


                          But why would the NS charter/purchase a dive tender/OPV when (assuming the counter mine capability on the new CPVs comes in the form of NSDS equipment) - and the redundancy will be there as there will be 2 of them?

                          Comment


                          • But why would the NS charter/purchase a dive tender/OPV
                            Given how suitable the NS diving unit found the ILV Grainualie for diving ops, something of that configuration would be ideal.

                            This baby, HMS Sentinel worked quite well for the UKRN and had been leased in, she worked as Falklands guard ship at one point, I've seen here at sea back in 1987 and looked very capable
                            Covid 19 is not over ....it's still very real..Hand Hygiene, Social Distancing and Masks.. keep safe

                            Comment


                            • On a utility basis ex oil industry units would be unbeatable.

                              Comment


                              • Again it depends what the DoD mean by "counter-mine & c-IED" for the new CPVs

                                If it is CD type ops that means 2-3 TEUs with all the NSDS equipment (including DCCC, ROV, SSS, etc). If it was, then these would be bespoken NS design. These would be CPVs with capability to act a dive tenders designed in. The P61 class already has this capability. So that would be 5 out of the 8 vessels. Not good VFM to buy a bespoken dive tender as well (an ETV maybe).

                                If it is a MCMV, then possibly could be a good idea.
                                Last edited by DeV; 29 December 2015, 20:45.

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