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  • HMS Clyde will be on her way to Bahrain.

    https://ukdefencejournal.org.uk/hms-...ld-to-bahrain/

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    • Originally posted by EUFighter View Post
      HMS Clyde will be on her way to Bahrain.

      https://ukdefencejournal.org.uk/hms-...ld-to-bahrain/
      An overseas Dutch Company Damen have built two OPV/Corvettes for the Pakistani navy based on the EITHNE design with twin funnels and flight deck similar in configuration and position to P31. Google them and go to Images for a great selection of photos.

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      • Originally posted by ancientmariner View Post
        An overseas Dutch Company Damen have built two OPV/Corvettes for the Pakistani navy based on the EITHNE design with twin funnels and flight deck similar in configuration and position to P31. Google them and go to Images for a great selection of photos.
        Saw that earlier, a fine looking ship, and you couldn't but help wonder what could have been if we had built more of her class.

        May as well mute this from the outset, unless you are familar with languages of the Indian Sub Continent.
        Last edited by na grohmiti; 13 November 2020, 17:34.

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        • Wasn’t there a USCG Cutter class based on Eithne ?

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          • No, common myth that the Bear class is based on the P31 design, but they were both of a similar time and Bear came first.

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            • Nothing is based on the Eithne design there have been variations of a theme but to prove direct linage back to Eithne is pure conjecture as if it there were a direct link someone would be in breach of copy right as it was never sold om
              Covid 19 is not over ....it's still very real..Hand Hygiene, Social Distancing and Masks.. keep safe

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              • Originally posted by hptmurphy View Post
                Nothing is based on the Eithne design there have been variations of a theme but to prove direct linage back to Eithne is pure conjecture as if it there were a direct link someone would be in breach of copy right as it was never sold om
                There was a big connection with Den Helder and NEVESBU in the design and oufit of P31 as a helicopter capable vessel. Damen's home place was Den Helder. Many plans and arraignments came from the Netherland Vessel Bureau. Obviously it is not exactly the same but the similarity's are interesting such as the split funnels, and the F.Dk not reaching the stern and the high freeboard.

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                • The Eithne was and still is a great design for a medium sized OPV. But it was not the first vessel with such a layout, the USCG Hamilton class had a very similar if larger layout. Today it could be contended that this type of layout can be found on several OPV designs: the Spanish Meteoro class, the NZ Otago class, the Luerssen OPV-85/90 classes and the Damen OPV range.

                  It is popular as it allows for a flight deck and hangar to be installed on relatively small vessels. Moving the funnels outboard frees the valuable centreline space for the hangar without needing to lengthen the vessel too much or having some crazy ducting to get the exhaust from the engines to the funnels. No one seems ever to want to go back to the County class destroyer layout!

                  A testimony to the design of the Eithne is that she can still hold her head up high in comparison to her more modern designs and if all of her systems had be updated and still operational she would be far ahead in many aspects. The exception might be the Luessern OPV/85/90 design due to their CMS. Their is a saying in the aviation community that "the only replacement for a DC-3 is another DC-3", and the same might be true for the Eithne but slightly modified. So a modernized (with lessons learnt) new Eithne would make a great replacement for the original Eithne.

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                  • Longer, broader, larger helideck, Hangar superstructure block to cover full beam. Openings at main deck for Caley davit and Rhib. Space for extra Rhibs when needed. Similar propulsion arrangement as P60s. etc.

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                    • The Arrowhead 120 - the little brother of the T31 - with an OPV weapons outfit would be nice

                      https://www.savetheroyalnavy.org/bab...e-competition/

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                      • Originally posted by Graylion View Post
                        The Arrowhead 120 - the little brother of the T31 - with an OPV weapons outfit would be nice

                        https://www.savetheroyalnavy.org/bab...e-competition/
                        The weakest part of builders proposals is actually putting ship's craft into the sea. Boats are deployed to put boarding groups either ashore or onto other craft . The tricky bit is releasing the boat cleanly with all parties already on board. The loading ledge on the port quarter would not work in an open sea. It would either push a lipped boat underwater or flip it over from underneath during a roll. Recovering craft requires the reverse sequence. Another matter I picked up in comments, is it true that the OTO76 is not designed for NGS?

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                        • Originally posted by Graylion View Post
                          The Arrowhead 120 - the little brother of the T31 - with an OPV weapons outfit would be nice

                          https://www.savetheroyalnavy.org/bab...e-competition/
                          What is the benefit of dumbing down a corvette/frigate design to be an OPV?
                          The Arrowhead 120 was designed to be a full frigate, to take the sensors, systems and weapons of such a vessel. Also it will have been design as a fighting vessel with numerous damage control zones. All of this will have driven the size of the vessel, so where is the advantage of the dumbed down design versus one of the many OPV designs that are available on the market. For example would a dumbed down Arrowhead-120 provide any advantage over a Holland class OPV?

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                          • Originally posted by EUFighter View Post
                            What is the benefit of dumbing down a corvette/frigate design to be an OPV?
                            The Arrowhead 120 was designed to be a full frigate, to take the sensors, systems and weapons of such a vessel. Also it will have been design as a fighting vessel with numerous damage control zones. All of this will have driven the size of the vessel, so where is the advantage of the dumbed down design versus one of the many OPV designs that are available on the market. For example would a dumbed down Arrowhead-120 provide any advantage over a Holland class OPV?
                            Having being involved in two new builds it is clear that mucking about with designs or changing dimensions has a Frankenstein effect. Ships are very influenced by bulkhead spacing and as far as stability, seakeeping and speed is concerned ( HP needed ) her length, breadth, and draft. Best place to get a ship is a draft specification and plenty of drawing office paper, followed by tank testing.

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                            • Originally posted by EUFighter View Post
                              What is the benefit of dumbing down a corvette/frigate design to be an OPV?
                              The Arrowhead 120 was designed to be a full frigate, to take the sensors, systems and weapons of such a vessel. Also it will have been design as a fighting vessel with numerous damage control zones. All of this will have driven the size of the vessel, so where is the advantage of the dumbed down design versus one of the many OPV designs that are available on the market. For example would a dumbed down Arrowhead-120 provide any advantage over a Holland class OPV?
                              Arrowhead 120 was designed for the Type 31 Royal Navy frigate competition. Which is a general purpose frigate (and also to give the UK shipbuilding industry something to do (under the National Shipbuilding Strategy with the hope of winning export orders)). When the competition was relaunched the Arrowhead 140 was selected.

                              If (big if) we were to enter the frigate game, the Type 31 would have to be considered as it will be a in service design in numbers. They plan to have 5 ships delivered by 2028 at UK£ 250M each. Based on Iver Huitfeldt design. With all the neccesary capabilities.
                              https://www.babcockinternational.com...09.10.2020.pdf
                              https://www.arrowhead140.com/

                              Arrowhead 120 would I assume be cheaper and have much of the same capabilities (and the 140 is a modifiication of its design) - afaik there are no orders but that shouldn't necessarily stop us (they will of course also learn a lot from the 140 build). It also has a smaller crew.
                              https://www.babcockinternational.com...EN-DIGITAL.pdf


                              Would the Holland Class's bigger size, helipad, Combat Management System, sensors justifiy it? There is still only so much they can do with the weapons they have? No SAMs, no SSMs, no ASW sonar

                              Arrowhead 120 would have all of those capabilities that are missing from the Holland Class




                              Holland is a OPV with helipad and good sensors plus limited self defence capabilities

                              Arrowhead 120/140 is a frigate with good sensors and good self defence (and offensive) capabailities
                              Last edited by DeV; 15 November 2020, 11:41.

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                              • Originally posted by DeV View Post
                                Would the Holland Class's bigger size, helipad, Combat Management System, sensors justifiy it? There is still only so much they can do with the weapons they have? No SAMs, no SSMs, no ASW sonar

                                Arrowhead 120 would have all of those capabilities that are missing from the Holland Class

                                Holland is a OPV with helipad and good sensors plus limited self defence capabilities

                                Arrowhead 120/140 is a frigate with good sensors and good self defence (and offensive) capabailities
                                The proposal was to dumb down the Arrowhead-120 to be an OPV, not to have a frigate! It was to this proposal that I was answering too.
                                If the proposal is to add AAW, ASW, CIWS etc then that is a corvette or frigate and should be called that and not an OPV.

                                As for the Holland class it would be easy to have a sonar added although adding weapons systems such as AAW, ASW, ASuW would not be easy. The advantage an Holland class would bring is its size for OPV operations. The Dutch call the class OPV's but the O is for Ocean as the class is expected to traverse the North Atlantic all around the year. Also the crewing requirement for the Holland class is around 54 while that for a Arrowhead would be around 120.

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