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  • Originally posted by DeV View Post
    The whole point of a RMP (or RAP for that matter) is that it integrates data from multiple sources. If it didn't all you'd have to is give each vessel a PC with internet access.

    A quick Google will tell you the NS one includes shore based radar and CCTV inputs. As well as Lirguard / VMS (not sure if this is fully integrated into the RMP or standalone.

    It could now (or in the future) include data from:
    Naval charts and/or GIS
    NS vessel radar input & imagery (and from other vessels if equipped (eg CIL)
    CASA radar input & imagery
    Various databases

    https://artes-apps.esa.int/projects/ng-rmp
    DeV, you replied to my post about using a SOSUS like setup to detect vessels and said:
    Or use a satellite
    Now I explicitly mentioned in the post you replied to:
    no AIS detected on Sat pass
    Your NG RMP uses satellites which repeat oceanic AIS packets that they detect, back down to the ground - if AIS is disabled, those satellites wont be any the wiser that a vessel is there. That was the whole point of my post!

    You put up that link to NG RMP as if it was a rebuttal to ropebags quip about the cost of operating satellites. The reality is commercial satellites are already up there repeating AIS frames captured mid ocean - we can see that information on marine traffic, so I think it's safe to assume the NS also utilises that data - but if the vessel is not transmitting, we don't know it's there unless:

    1) An OPV can detect it (it will need to have a LOS, so very limited detection range or you'll have to hope the crew are playing on LF/MF/HF and you happen to be listening at the right time)
    2) CASA detects it - much more likely, provided it's up there and the radar is working.
    3) A tip off from a friendly neighbour

    So again, a satellite AIS repeater is as much use as a Secondary Surveillance Radar - it requires a co-operative target. If you want to get in to active detection with satellites e.g. with radar, be prepared to spend hundreds of millions.

    Shore based CCTV and VHF/UHF radar is severely limited in range.

    Comment


    • Lad's we do have a thread for the subs, can't we move this stuff to there?


      Mod, all submarine stuff has dived to down here:http://forum.irishmilitaryonline.com...anks-was-taken
      Last edited by Turkey; 4 March 2016, 04:52.

      Comment


      • Originally posted by pym View Post
        DeV, you replied to my post about using a SOSUS like setup to detect vessels and said:


        Now I explicitly mentioned in the post you replied to:


        Your NG RMP uses satellites which repeat oceanic AIS packets that they detect, back down to the ground - if AIS is disabled, those satellites wont be any the wiser that a vessel is there. That was the whole point of my post!

        You put up that link to NG RMP as if it was a rebuttal to ropebags quip about the cost of operating satellites. The reality is commercial satellites are already up there repeating AIS frames captured mid ocean - we can see that information on marine traffic, so I think it's safe to assume the NS also utilises that data - but if the vessel is not transmitting, we don't know it's there unless:

        1) An OPV can detect it (it will need to have a LOS, so very limited detection range or you'll have to hope the crew are playing on LF/MF/HF and you happen to be listening at the right time)
        2) CASA detects it - much more likely, provided it's up there and the radar is working.
        3) A tip off from a friendly neighbour

        So again, a satellite AIS repeater is as much use as a Secondary Surveillance Radar - it requires a co-operative target. If you want to get in to active detection with satellites e.g. with radar, be prepared to spend hundreds of millions.

        Shore based CCTV and VHF/UHF radar is severely limited in range.
        I was actually suggesting satellite imagery - be it radar, IT or something else (as opposed to AIS).

        Yes very expensive as would a SOSUS type system but come to think of it both the EU and NATO have deep interest in what is happening in the North Atlantic for various reasons including defence/military, drugs and other smuggling and SAR. Some nations may already have the capability in use. If we (or the EU) could get access to it, it could also feed radar into the RMP.

        There are at least a couple of CASA flights per week which feeds into it, not sure if it is live but it still builds Int which is used to assess risk.

        There is also the 18 country EDA MARSUR project and EC Common Info Sharing Environment.

        Say there is a vessel without its AIS transponder turned on, if spotted by the CASA on patrol (remember it's a long range radar, it possibly becomes something that resources will be diverted to investigate. This is the as is situation. Is it perfect no?

        It would take years or work and real time observation just to make up a SOSUS sonar library.

        It was then when the RMP came to mind.
        Last edited by DeV; 4 March 2016, 14:37.

        Comment


        • For information. SOSUS or similar are deep set hydrophones designed to give warning of large nuclear submarines. They would not contribute to the Surface RMP which in turn is fed by tracked AIS data as available, reported or detected data from surface and air radars, DF signals, self reported data to shore stations, satellite photo imagery and in some cases HFSWR ( High Frequencey Surface Wave Radar). The Canadians have two such stations, one at Cape Race, it proves to have a reasonable range of 140nm but likes targets to be on a fixed course, without manoeuvre, as at each manoeuvre it reidentifies the target as a new target with a new track number. It also has to battle with limited bandwidth and ionospheric interference. It can make a contribution and papers are available by googling.
          There are about nine classes of ship identifiers on AIS and in most cases are hard wired to prevent SWX OFF. I believe naval vessels can Switch Off.

          Comment


          • Eithne Replacement: This Old Chestnut

            I decided to take a fresh look this weekend at the ship-porn I've been amassing regarding a possible replacement for Eithne.

            International engagement will be high on the list of this ship's tasking.

            This may include, but will not necessarily be limited to; chasing the Canadian Coast Guard out of the Irish EEZ, humanitarian and peace keeping operations, anti-piracy, UN, EU, PfP missions, trade missions and good-will missions. All of this is in addition to the Navy's broad spectrum of day-to-day tasks deriving from the open ocean patrol mission entrusted to it by the citizens and the State.

            It will be the first Naval Service vessel equipped to offer direct support to the Army, Air Corps, and the Gardaí in the fulfillment of their international engagement missions.

            The supposed ideal contenders, at least if the contributors to IMO are to be believed, are the Danish Absalon class support ship and the Dutch designed Damen Crossover, which offers a hybrid solution between a frigate and a traditional naval transport auxiliary.


            Damen Crossover 131 Cutaway

            Damen have not published the vehicle sea-lift capability of the Crossover, a capacity usually measured in units known as lane meters.

            This makes it difficult to assess the vessel's potential support utility to, for instance, an Army overseas peacekeeping mission.

            Once upon a lifetime ago I used to be a pretty decent draughtsman, so I decided to take a trip down memory lane, and 'solve' the lane metre capacity of the Crossover from published illustrations.

            A note of caution: These are only volumetric deductions, I have no expertise in judging the weight implications of any of what follows. Even then for any of the findings to have any value whatsoever we have to assume that the public source diagrams are derived from an accurate engineering study. If they were drawled out by a bored art student intern during his or her lunchtime then none of the following means anything at all.



            Deductions and Observations

            Long Story Short: Ro-ro capacity of the two vessels illustrated above, excluding the X Deck (Boat handling deck).

            Crossover 131 Logistic has 493 lane metres of ro-ro capacity, including the flight deck and the aircraft/vehicle hangar.
            Crossover 139 Logistic has 589 lane metres of ro-ro capacity, including the flight deck and the aircraft/vehicle/Rhib hangar. (Illustrated).
            Calculations assume a very generous 3.5m lane width.
            For all you ever wanted to know about lane meters, but then decided you didn't, see the notes towards the bottom of this post.

            Estimated Army foreign mission sea-lift requirements:

            EU ISTAR 530 lane metres + 20 TEUs requiring 1 Crossover 139 Logistic (Heavy Load)
            Coy Group 320 lane metres + 20 TEUs requiring 1 Crossover 139 Logistic (Standard Load)
            Btn Group 725 lane metres + 90 TEUs requiring 2 Crossover 139 Logistic (Intermediate Load)

            24 TEUs Stacked 2 high on flightdeck 6 across (15m) take up 12.2m of deck or 48.8 lane metres (4 lanes at 3.5m wide each)
            96 TEUs Stacked 2 high on flightdeck 6 across (15m) take up 48.8m of deck or 195.2 lane metres (4 lanes at 3.5m wide each)

            If stored on a vehicle deck, 1 TEU loaded on a ro-ro cassette takes up 6.1m of (2.5m wide) lane meter space.

            Lane Metre: A unit of deck area for ro-ro ships: cargo vessels designed so that containers or other cargo can be rolled on and off the decks of the ship. A lane is a strip of deck a minimum of 1.95 metres wide. A 'minimum' lane metre is an area of deck one lane wide and one metre long, that is, 1.95 square metres. Typical car lanes on a ro-ro ship are 2 metres wide, standard truck lanes are typically up to 3 metres wide.

            Anything over 3 metres is generally reserved for oversize loads or private vehicles towing caravans or trailers.

            A Piranha III APC, a vehicle expected to be deployed on UN peacekeeping missions, is 2.7 metres wide. I have assumed a generous 3.5 metre lane width on the vehicle decks due to the poor standard of the sources I am using to estimate internal volumes and to speed the loading process. Remember this is a 20 ton armoured vehicle that may have to be reversed into the vehicle deck. If the actual allowable width of the vehicle lanes is 3.25, or even 3 metres, the capacities calculated above will not be affected. Required loading times may increase however.

            Lane Metre workings: Vehicle Decks + (Hangar + Flightdeck - Interface Hangar/Flightdeck) = Total available deck length / 4 vehicle lanes

            Crossover 131 L 28.75 x 2 + (28.75 + 42.10 - 5.00) = 123.35 x 4 = 493.40 Lane Metres
            Crossover 139 L 36.75 x 2 + (36.75 + 42.10 - 5.00) = 147.35 x 4 = 589.40 Lane Metres

            Comment


            • Originally posted by The Usual Suspect View Post
              I decided to take a fresh look this weekend at the ship-porn I've been amassing regarding a possible replacement for Eithne.

              International engagement will be high on the list of this ship's tasking.

              This may include, but will not necessarily be limited to; chasing the Canadian Coast Guard out of the Irish EEZ, humanitarian and peace keeping operations, anti-piracy, UN, EU, PfP missions, trade missions and good-will missions. All of this is in addition to the Navy's broad spectrum of day-to-day tasks deriving from the open ocean patrol mission entrusted to it by the citizens and the State.

              It will be the first Naval Service vessel equipped to offer direct support to the Army, Air Corps, and the Gardaí in the fulfillment of their international engagement missions.

              The supposed ideal contenders, at least if the contributors to IMO are to be believed, are the Danish Absalon class support ship and the Dutch designed Damen Crossover, which offers a hybrid solution between a frigate and a traditional naval transport auxiliary.


              Damen Crossover 131 Cutaway

              Damen have not published the vehicle sea-lift capability of the Crossover, a capacity usually measured in units known as lane meters.

              This makes it difficult to assess the vessel's potential support utility to, for instance, an Army overseas peacekeeping mission.

              Once upon a lifetime ago I used to be a pretty decent draughtsman, so I decided to take a trip down memory lane, and 'solve' the lane metre capacity of the Crossover from published illustrations.

              A note of caution: These are only volumetric deductions, I have no expertise in judging the weight implications of any of what follows. Even then for any of the findings to have any value whatsoever we have to assume that the public source diagrams are derived from an accurate engineering study. If they were drawled out by a bored art student intern during his or her lunchtime then none of the following means anything at all.



              Deductions and Observations

              Long Story Short: Ro-ro capacity of the two vessels illustrated above, excluding the X Deck (Boat handling deck).

              Crossover 131 Logistic has 493 lane metres of ro-ro capacity, including the flight deck and the aircraft/vehicle hangar.
              Crossover 139 Logistic has 589 lane metres of ro-ro capacity, including the flight deck and the aircraft/vehicle/Rhib hangar. (Illustrated).
              Calculations assume a very generous 3.5m lane width.
              For all you ever wanted to know about lane meters, but then decided you didn't, see the notes towards the bottom of this post.

              Estimated Army foreign mission sea-lift requirements:

              EU ISTAR 530 lane metres + 20 TEUs requiring 1 Crossover 139 Logistic (Heavy Load)
              Coy Group 320 lane metres + 20 TEUs requiring 1 Crossover 139 Logistic (Standard Load)
              Btn Group 725 lane metres + 90 TEUs requiring 2 Crossover 139 Logistic (Intermediate Load)

              24 TEUs Stacked 2 high on flightdeck 6 across (15m) take up 12.2m of deck or 48.8 lane metres (4 lanes at 3.5m wide each)
              96 TEUs Stacked 2 high on flightdeck 6 across (15m) take up 48.8m of deck or 195.2 lane metres (4 lanes at 3.5m wide each)

              If stored on a vehicle deck, 1 TEU loaded on a ro-ro cassette takes up 6.1m of (2.5m wide) lane meter space.

              Lane Metre: A unit of deck area for ro-ro ships: cargo vessels designed so that containers or other cargo can be rolled on and off the decks of the ship. A lane is a strip of deck a minimum of 1.95 metres wide. A 'minimum' lane metre is an area of deck one lane wide and one metre long, that is, 1.95 square metres. Typical car lanes on a ro-ro ship are 2 metres wide, standard truck lanes are typically up to 3 metres wide.

              Anything over 3 metres is generally reserved for oversize loads or private vehicles towing caravans or trailers.

              A Piranha III APC, a vehicle expected to be deployed on UN peacekeeping missions, is 2.7 metres wide. I have assumed a generous 3.5 metre lane width on the vehicle decks due to the poor standard of the sources I am using to estimate internal volumes and to speed the loading process. Remember this is a 20 ton armoured vehicle that may have to be reversed into the vehicle deck. If the actual allowable width of the vehicle lanes is 3.25, or even 3 metres, the capacities calculated above will not be affected. Required loading times may increase however.

              Lane Metre workings: Vehicle Decks + (Hangar + Flightdeck - Interface Hangar/Flightdeck) = Total available deck length / 4 vehicle lanes

              Crossover 131 L 28.75 x 2 + (28.75 + 42.10 - 5.00) = 123.35 x 4 = 493.40 Lane Metres
              Crossover 139 L 36.75 x 2 + (36.75 + 42.10 - 5.00) = 147.35 x 4 = 589.40 Lane Metres
              When we reach a ship length of 131metres, we expect a beam of 20.40 metres. The useable width of Cork dockyard's Graving Dock is 21.3metres. Any ship we select should not exceed 18.5metre beam to allow some manoeuvering space. I would look at ships with a length of 118.75 metres and 18.5 beam capable of meeting logistical loads up to Coy. Gp strengths only, but with a topline defence/ offence suites. The ship needs verstility of being able to meet an operational best draft by use of ballasting system to replace absent cargo.

              Comment


              • Originally posted by ancientmariner View Post
                When we reach a ship length of 131metres, we expect a beam of 20.40 metres. The useable width of Cork dockyard's Graving Dock is 21.3metres. Any ship we select should not exceed 18.5metre beam to allow some manoeuvering space. I would look at ships with a length of 118.75 metres and 18.5 beam capable of meeting logistical loads up to Coy. Gp strengths only, but with a topline defence/ offence suites. The ship needs verstility of being able to meet an operational best draft by use of ballasting system to replace absent cargo.
                Or we build a bigger graving dock.
                "He is an enemy officer taken in battle and entitled to fair treatment."
                "No, sir. He's a sergeant, and they don't deserve no respect at all, sir. I should know. They're cunning and artful, if they're any good. I wouldn't mind if he was an officer, sir. But sergeants are clever."

                Comment


                • Originally posted by morpheus View Post
                  Or we build a bigger graving dock.
                  Indeed - restricting the size/efficacy of overseas deployments till 2055 or so for the want of a load of Hilti drills and a few thousand tons of concrete has got to be the dumbest, most self-defeating idea in the history of human thought.

                  Comment


                  • Originally posted by ancientmariner View Post
                    When we reach a ship length of 131metres, we expect a beam of 20.40 metres. The useable width of Cork dockyard's Graving Dock is 21.3metres. Any ship we select should not exceed 18.5metre beam to allow some manoeuvering space. I would look at ships with a length of 118.75 metres and 18.5 beam capable of meeting logistical loads up to Coy. Gp strengths only, but with a topline defence/ offence suites. The ship needs verstility of being able to meet an operational best draft by use of ballasting system to replace absent cargo.
                    A vessel capable of carrying an EUBG ISTAR TF or Mech Coy Gp (plus say the engineer assets etc to set up camp) - whichever is larger - would get higher utilisation, be cheaper and be better VFM. This "smaller" vessel would also I assume have better seakeeping while empty.

                    Originally posted by morpheus View Post
                    Or we build a bigger graving dock.
                    Originally posted by ropebag View Post
                    Indeed - restricting the size/efficacy of overseas deployments till 2055 or so for the want of a load of Hilti drills and a few thousand tons of concrete has got to be the dumbest, most self-defeating idea in the history of human thought.
                    The size of the dock available only effects maintenance, not operational capabilities. However, there would be implications.

                    Comment


                    • Ancientmariner,

                      Originally posted by ancientmariner View Post
                      When we reach a ship length of 131metres, we expect a beam of 20.40 metres. The useable width of Cork dockyard's Graving Dock is 21.3metres. Any ship we select should not exceed 18.5metre beam to allow some manoeuvering space. I would look at ships with a length of 118.75 metres and 18.5 beam capable of meeting logistical loads up to Coy. Gp strengths only, but with a topline defence/ offence suites. The ship needs verstility of being able to meet an operational best draft by use of ballasting system to replace absent cargo.
                      Although far from being an expert (or not even claiming any real knowledge of naval matters), and certainly not questioning your calculations, I would suggest that the new vessel need not be limited to a beam of 18.5 metres, as when the Naval Service last issued their requirements for an EPV (irrespective of whether the WP proposed MPV is for the same roles), they were willing to accept a beam of 20 metres:

                      Length 130 – 140M
                      Beam 16-20 m
                      Draft 4.0- 5.0 m
                      (according to the Specs thread).

                      Comment


                      • Originally posted by ias View Post
                        Ancientmariner,



                        Although far from being an expert (or not even claiming any real knowledge of naval matters), and certainly not questioning your calculations, I would suggest that the new vessel need not be limited to a beam of 18.5 metres, as when the Naval Service last issued their requirements for an EPV (irrespective of whether the WP proposed MPV is for the same roles), they were willing to accept a beam of 20 metres:

                        Length 130 – 140M
                        Beam 16-20 m
                        Draft 4.0- 5.0 m
                        (according to the Specs thread).
                        Despite the smart remarks from other pundits ships are designed to carry out their planned naval duties keeping in mind seakeeping qualities and the future home porting of the ship(s) including on going maintenance and periodic layups for maintenance. The point for consideration with bigger vessels is berthage and future drydock facilities. Your choices are restricting beam versus length ratio which are the major factors effecting speed, lateral accelerations, and fit into drydocks. Our current ships have a ratio Beam to Length of about 6.42. The question is what is the maximum ship beam and lenght that will fit into your home port Drydock. Cork could manage, with assisting tugs and reasonable weather, a vessel of 20metre beam with 0.65m clearance either side. 18.5 metres is an acceptable average of 16-20m beam but that is the choice of the Naval Planners.
                        Last edited by ancientmariner; 14 April 2016, 11:36.

                        Comment


                        • Originally posted by The Usual Suspect View Post
                          love the laser turrets on the superstructure.

                          better view of one on a different mounting

                          Last edited by X-RayOne; 14 April 2016, 14:18.
                          An army is power. Its entire purpose is to coerce others. This power can not be used carelessly or recklessly. This power can do great harm. We have seen more suffering than any man should ever see, and if there is going to be an end to it, it must be an end that justifies the cost. Joshua Lawrence Chamberlain

                          Comment


                          • Originally posted by X-RayOne View Post
                            love the laser turrets on the superstructure.
                            Laser turrets. Sure.

                            https://en.m.wikipedia.org/wiki/Rhei...Millennium_Gun

                            Rheinmetall are working on one though..

                            http://www.rheinmetall-defence.com/e...hel_live_fire/
                            Last edited by Jetjock; 14 April 2016, 16:30.

                            Comment


                            • Originally posted by ancientmariner View Post
                              Despite the smart remarks from other pundits ships are designed to carry out their planned naval duties keeping in mind seakeeping qualities and the future home porting of the ship(s) including on going maintenance and periodic layups for maintenance. The point for consideration with bigger vessels is berthage and future drydock facilities. Your choices are restricting beam versus length ratio which are the major factors effecting speed, lateral accelerations, and fit into drydocks. Our current ships have a ratio Beam to Length of about 6.42. The question is what is the maximum ship beam and lenght that will fit into your home port Drydock. Cork could manage, with assisting tugs and reasonable weather, a vessel of 20metre beam with 0.65m clearance either side. 18.5 metres is an acceptable average of 16-20m beam but that is the choice of the Naval Planners.
                              I hope you don't think I was making "smart remarks", my comments were genuine, I have no knowledge of ship design except what I read here and other places on the internet. I certainly value your input to the debates on this board, it is very obvious that you are extremely knowledgeable, I was only pointing out that the NS seem to be willing to accept a beam of 20m.

                              Comment


                              • Originally posted by ropebag View Post
                                Indeed - restricting the size/efficacy of overseas deployments till 2055 or so for the want of a load of Hilti drills and a few thousand tons of concrete has got to be the dumbest, most self-defeating idea in the history of human thought.
                                The solution is simpler. Seeing as the owners of the Drydock in Cork Dockyard are reluctant to invest, why not instead purchase/lease a larger floating dock?

                                For now, everything hangs on implementation of the CoDF report.

                                Comment

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