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  • Originally posted by na grohmití View Post
    It's no rumour, it is discussed in the interim accident report. Indeed there is a suggestion that all vessels based on this design may have this design fault.

    https://www.aibn.no/Marine/Investiga...-File&attach=1
    In a normal CPP shafting/control system the blades are controlled either from a push/pull rod system from servo motors at the gear box OR a hydraulic system where the servo motor is in the hub. However in both cases as lines enter the gearbox area they are fitted with non-return devices. I cannot understand flooding internally in the ship, through hollow shafting, unless there was free flooding in an aft compartment AND the shafts were broken to allow water to ingress. Question arises is there a non return system on hollow shafting or does it free flow once broken. This conundrum effects thousands of ships fitted with CPP and is it ONE of the reasons some ships are fitted with Azipods?

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    • The Norwegian Navy have released underwater video of the damage which they took while they were removing all live ordnance from the ship.
      Damage seems to be very extensive, it is amazing they managed to get her beached even if now she has slipped into the deep.

      https://www.youtube.com/watch?v=hAvmkq7gW78

      Comment


      • Originally posted by EUFighter View Post
        The Norwegian Navy have released underwater video of the damage which they took while they were removing all live ordnance from the ship.
        Damage seems to be very extensive, it is amazing they managed to get her beached even if now she has slipped into the deep.

        https://www.youtube.com/watch?v=hAvmkq7gW78
        Any new vessels for the Naval Service must take account of all those construction processes that may cause or contribute to immediate ingress of seawater and its spread beyond planned watertight boundaries. There have been two examples of rapid flooding in ships lately e.g. Helge Ingstad above and the EMMA Maersk.
        The HI incident was caused by collision and a consequent failure of watertight integrity in shafting and boundaries causing flooding to spread.
        In the EM incident, while entering the approaches of the Suez canal, she had a failure in the aft end thruster tunnel which caused seawater to rapidly flood the long shaft tunnel and, despite closing a watertight door, the amount of water pressure caused the watertight integrity of a bulkhead to fail, with the ship losing all power to the flood water. Luckily 5 tugs were at hand and by using them and manually controlled anchors and chain they got her alongside a container berth. It cost about E40m to repair.
        A high proportion of weaknesses in ship construction must be a failure of oversight both within yards, designers , and organisations ordering ships. Ships have to have propulsion, Stabilisers , and thrusters, and they must be designed in with watertight integrity in mind.

        Comment


        • The standard to which the Helge Ingstad was built and what we build out vessels too are different; one is to full MilStd while the other is commercial with a bit of mil added on. But even the high mil specs need to be looked at. A modern naval vessel is highly automated, keeps running costs down etc. But it also means that for damage control many fewer bodies are available and here I see a problem. A vessel the size of the Helge Ingstad in the 1950's/60's would have had a crew of around 360, three times more that today. This meant that there were a lot of people to do damage control. These are now missing so it might be time to update standard to take the new reality into account.

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          • Well it depends of course, the USN runs a much larger crew per ship than Euro designs, however to be honest given the scale of damage that the HI took I don't think any level of damage control would have saved her, I mean she had multiple compartments breached from top to bottom, with reported shaft failures as well, and I'm not sure she even had watertight set. Given the damage some of the Burkes have taken have come close to critical I don't know if one of them could have shrugged off this scale of damage either.

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            • Originally posted by Sparky42 View Post
              Well it depends of course, the USN runs a much larger crew per ship than Euro designs, however to be honest given the scale of damage that the HI took I don't think any level of damage control would have saved her, I mean she had multiple compartments breached from top to bottom, with reported shaft failures as well, and I'm not sure she even had watertight set. Given the damage some of the Burkes have taken have come close to critical I don't know if one of them could have shrugged off this scale of damage either.
              Perhaps some of the critical flooding may have been exacerbated by tug push, causing lipping of high damage , and crunching the exposed lengths of shafting.
              The USCG are commencing to build a new Heritage class cutter 110m x 16m x5.2m. She is quite p31 in basic format, hangar and flight deck forward of transom .She is armed to give basic Defence but fitted to upgrade to a wartime role-57mm fwd BAE MK 38 aft, auto controlled 12.7mm twins and many others manually operated. She also has latest decoy system and 2d sensors with FCS. Her crew is US style as you say at 123 personnel some 75 more than our P60's
              I'm glad she is armed 360, capable of shore support fire, but she looks impeded with firing arcs ahead obscured by bow flare. Lifting the gun a meter or so would help.

              Comment


              • The Heritage class cutters are a development of a VARD design and some of the design feathers can be seen on our P60's and the NZ Protector 85m vessels. They are fitted with the same Saab Sea Giraffe AMB 3d radar as the LCS vessels. Also they are fitted for but not with Phalanx should the need arise.

                Comment


                • Originally posted by na grohmití View Post
                  I heard earlier this week, from a source I consider very reliable, that the proposed Extended Patrol/Multi Role vessel has increased in displacement from just under 4000 tonnes as outlined in the original EPV RFT to a vessel of up to 9000 tonnes displ. A budget of €200m was also mentioned. Double that being considered in 2006. This opens us to many more options. Presumably the NS have given up on the idea of fitting it in the Basin, given that there wil be plenty of available quay space in Cork City by the time the vessel would be in service.
                  This brings us up to the range of the Damen Enforcer LPD9000, for example. Not for a minute suggesting this is where we are going, but it definitely broadens the available designs already in service.


                  Is it possible that a mini JSS is being contemplated, with an emphasis towards matériel sealift and modular mission space, and away from AOR and amphibious infantry accommadation?

                  If so, may I suggest that the hosting of two medivac helos should be considered a possible core requirement?

                  In future peace-keeping and humanitarian roles, the lack of a top-tier medivac capability is going to become increasingly restrictive, not unlike during the Balkan Wars when the lack of modern APCs cutrailed Irish deployability and deployment. To be clear, I'm not suggesting that we develop this capability ourselves, but rather that we develop the capability to host someone else's helos, with all nescessary support, for an extended period of time.

                  Our new best friends in the world, An Sraith Hansa Nua, would have any number of suitable elements that could be deployed and those we cooperate most closely with already, the Finns and the Swedes, won't be acquiring comparable blue-water assets anytime soon.

                  In that context, a mini JSS, scaled between the Dutch LPDs and the Danish Absalon Support Ships is probably approaching the sweet spot, in terms of deployable geo-political utility, as a one ship buy for the Irish Naval Service.

                  Comment


                  • Originally posted by EUFighter View Post
                    The Heritage class cutters are a development of a VARD design and some of the design feathers can be seen on our P60's and the NZ Protector 85m vessels. They are fitted with the same Saab Sea Giraffe AMB 3d radar as the LCS vessels. Also they are fitted for but not with Phalanx should the need arise.
                    I forgot to mention that the USCG cutter will receive suitable armour protection against the type of threat one would expect in pre-conflict hot spots. The idea is to protect vital equipment and crew from small arms fire and shrapnel. We should do the same and retro fit. It might add up to 100 tonnes for a largish vessel-bridge sides, ops areas, accommodation, weapon areas, etc.

                    Comment


                    • Originally posted by ancientmariner View Post
                      I forgot to mention that the USCG cutter will receive suitable armour protection against the type of threat one would expect in pre-conflict hot spots. The idea is to protect vital equipment and crew from small arms fire and shrapnel. We should do the same and retro fit. It might add up to 100 tonnes for a largish vessel-bridge sides, ops areas, accommodation, weapon areas, etc.
                      Although I agree that NS vessels should be equipped so they are protected when they get sent to areas of low/medium level conflict. While adding sensors, armour and defensive aids would be good, a lot of this added weight will be top side and thus have an effect on the stability of the vessels. Hopefully there has been a margin built in to allow for upgrade/updates

                      Comment


                      • Originally posted by EUFighter View Post
                        Although I agree that NS vessels should be equipped so they are protected when they get sent to areas of low/medium level conflict. While adding sensors, armour and defensive aids would be good, a lot of this added weight will be top side and thus have an effect on the stability of the vessels. Hopefully there has been a margin built in to allow for upgrade/updates
                        In the past naval vessels have been designed with a built in redundancy. Sensor antennae are light. Armour mounted on superstructure is low on the c/g. Extra weaponry would have a negligible influence on stability unless you decide to mount your heaviest weapon on the uppermost part of the ship.
                        I remember hearing many years ago that the P20 class were designed to carry 3 times their normal crew, in the event of rescuing survivors etc. The P30, P50 and P60 class demonstrated this capability and more in the med. Rescuees are moving freight, that can impact on your stability, but no ship was hampered in their operation by this considerable extra weight. Eithne carried them on the heliceck and in the hangar. The others carried them all up top ahead of the funnel.

                        Eithne has been designed to carry an extra 5 tonne on her helideck. More recently she has been approved by naval engineers to carry up to 8 TEUs on her helideck, or 4 10 tonne AFVs.

                        Roisin and Niamh are designed to carry one TEU aft.

                        All the Samuel Beckett class are designed to carry 3 TEU aft (with associated electrical services).

                        The redundant space has already been built in.
                        For now, everything hangs on implementation of the CoDF report.

                        Comment


                        • Originally posted by na grohmití View Post
                          In the past naval vessels have been designed with a built in redundancy. Sensor antennae are light. Armour mounted on superstructure is low on the c/g. Extra weaponry would have a negligible influence on stability unless you decide to mount your heaviest weapon on the uppermost part of the ship.
                          I remember hearing many years ago that the P20 class were designed to carry 3 times their normal crew, in the event of rescuing survivors etc. The P30, P50 and P60 class demonstrated this capability and more in the med. Rescuees are moving freight, that can impact on your stability, but no ship was hampered in their operation by this considerable extra weight. Eithne carried them on the heliceck and in the hangar. The others carried them all up top ahead of the funnel.

                          Eithne has been designed to carry an extra 5 tonne on her helideck. More recently she has been approved by naval engineers to carry up to 8 TEUs on her helideck, or 4 10 tonne AFVs.

                          Roisin and Niamh are designed to carry one TEU aft.

                          All the Samuel Beckett class are designed to carry 3 TEU aft (with associated electrical services).

                          The redundant space has already been built in.
                          I just wanted to make the point that there should be margin, even if we expect there too be it seems in some (not all) modern vessels they have limited margin.

                          Comment


                          • Originally posted by The Usual Suspect View Post


                            Is it possible that a mini JSS is being contemplated, with an emphasis towards matériel sealift and modular mission space, and away from AOR and amphibious infantry accommadation?

                            If so, may I suggest that the hosting of two medivac helos should be considered a possible core requirement?

                            In future peace-keeping and humanitarian roles, the lack of a top-tier medivac capability is going to become increasingly restrictive, not unlike during the Balkan Wars when the lack of modern APCs cutrailed Irish deployability and deployment. To be clear, I'm not suggesting that we develop this capability ourselves, but rather that we develop the capability to host someone else's helos, with all nescessary support, for an extended period of time.

                            Our new best friends in the world, An Sraith Hansa Nua, would have any number of suitable elements that could be deployed and those we cooperate most closely with already, the Finns and the Swedes, won't be acquiring comparable blue-water assets anytime soon.

                            In that context, a mini JSS, scaled between the Dutch LPDs and the Danish Absalon Support Ships is probably approaching the sweet spot, in terms of deployable geo-political utility, as a one ship buy for the Irish Naval Service.
                            The idea of the JSS for the Dutch Navy was to combine an AOR with a LPH and this gives a large vessel. Looking at the Enforcer design I would expect that the next iteration could evolve along the lines of the multi-role frigates starting to come on the market. In this I would expect that the hanger becomes more a flexible mission space. Being able to take a minimum of two mid-sized helicopters but with some cross-deck flexible system either for more helicopters, LCVP/CB90 sized boats for containerized mission modules. There will be a need to be able to offer much more flexibility. So even if there is a level 2 medical facility through additional modules in the mission hanger/bay it could be upgraded to a level 3.

                            As for the need for RAS this was a key driver in the Dutch JSS as it was replacing their AORs but it is not a high priority. However removing the dock well and having a longing ramp system means that internally there is no longer a need for the associated ballast tanks. Through re-arranging some of the internals the space could be utilized for fuel which would also be needed even in a HRO.

                            As the cost of a one off design is a high percentage of the cost of the vessel it would be good to see if such a vessel could become a PESCO project. The original Enforcer vessels will all be nearing the end of their lives in 10-15 years and a common EU platform would be good. Even if we order today it is likely the lead time would be 4-5 years so this would fit with being the lead/prototype for the next generation of Enforcer vessels.

                            Comment


                            • Originally posted by The Usual Suspect View Post


                              Is it possible that a mini JSS is being contemplated, with an emphasis towards matériel sealift and modular mission space, and away from AOR and amphibious infantry accommadation?

                              If so, may I suggest that the hosting of two medivac helos should be considered a possible core requirement?

                              In future peace-keeping and humanitarian roles, the lack of a top-tier medivac capability is going to become increasingly restrictive, not unlike during the Balkan Wars when the lack of modern APCs cutrailed Irish deployability and deployment. To be clear, I'm not suggesting that we develop this capability ourselves, but rather that we develop the capability to host someone else's helos, with all nescessary support, for an extended period of time.

                              Our new best friends in the world, An Sraith Hansa Nua, would have any number of suitable elements that could be deployed and those we cooperate most closely with already, the Finns and the Swedes, won't be acquiring comparable blue-water assets anytime soon.

                              In that context, a mini JSS, scaled between the Dutch LPDs and the Danish Absalon Support Ships is probably approaching the sweet spot, in terms of deployable geo-political utility, as a one ship buy for the Irish Naval Service.
                              It is interesting to look at “An Sraith Hansa Nua”, at the moment it is mainly fiscal focused but it could develop further. However for the next decade I do not see much interest coming from these countries in “out of area” operations. They are focusing more and more on home defence due to the big bad neighbour to their east…..hopefully our one stays in line!!

                              That is not to say we should not try and further our co-operation with our traditional friends and develop new ones like with Austria and the Baltic nations. Looking at sea-lift, a vessel is not just for the next decade but beyond that. So taking a long term view might mean we have to take the lead, the lead to propose something like the EU Heavylift Air Wing.

                              The Germans do now share the Dutch JSS and have a sea-lift ship sharing scheme with the Danes so it is not totally new. It could be that we come together with the Swedes/Finn etc and develop the capability together.

                              Comment


                              • Yeah it will be interesting to see how the relationships of the EU evolve post Brexit over the next decade or so, certainly I think some of our "traditional" positions are going to have to change. As I've said before I think we should be looking at what designs might fit for us while bringing something of use to more than just the DF if you know what I mean.

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