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  • Naval vs Commercial Standards

    I have seen comments lately that some naval vessels are built to "commercial" instead of "naval" standards. Two examples that I can think of are HMS Ocean and the Danish Absalon-class. What exactly is the difference? Is it strength, redundancy of systems, watertight integrity, what? Inquiring minds want to know.

  • #2
    This should give you what you want
    http://www.thinkdefence.co.uk/2012/1...lding-rules-2/
    It should be noted that AFAIK there are no global ship building standards for naval ships (individual nations having their own) but there are for commercial ones.
    In 2009 the International Maritime Organisation (IMO) approved of improved shipbuilding standards aimed at passenger and cargo ships. The need for these arose out of the loss of the cruise ship Explorer (built 1969) which sank in the Antarctic hours after hitting an iceberg. There were no fatalities. The new standards concentrate on increased survivability in case of an accident.
    In May 2005, the US Defense Department completed a shipbuilding industrial base study, finding that “large technology gaps exist in some U.S. shipyards [compared with global competition], and shipbuilding designs need to be optimized for state-of-the-art military vessels.” Work has since gone on to produce agreed standardss and construction technology between the US Navy, Coast Guard and US shipyards. However this seems to have concentrated on efficiency and cost cutting. Naval shipyards have often been notorious for "Spanish practices" and waste even as far back as Earl St Vincent (John Jervis) and his attempted reforms of British naval shipyards in Nelson's time.
    Human history becomes more and more a race between education and catastrophe (H G Wells)
    Mit der Dummheit kaempfen Goetter selbst vergebens (Friedrich von Schiller)

    Comment


    • #3
      It varies depending on the country involved.

      The actual design of warships is usually predicated on one of two basic ideas around survivability of the ship:

      Three compartment, where the design allows for three major compartments or subdivisions of the ship can flood and the ship will remain afloat.

      The other is a 60% rule. The US uses this one. 60% of the waterline volume of the ship can flood to the second deck and the ship will remain afloat.

      As far as details, commercial designs don't take damage into consideration other than in terms of environmental safety. For example, following the Exxon Valdez and other accidents with tankers almost all are now double hull to prevent spills.

      With naval ships the layout of the electrical system is far more resistant and redundant than on a commercial ship. The system will generally have more capacity too.
      Small warships will have their distribution system split fore and aft port and starboard with a cross connect at some point (think of a Z or S configuration) along the length of the ship to maximize survivability of the some of the system after damage. They will have at least one emergency generator aboard too.
      On large ships a ring bus is used for maximum survivability.

      Firemain and pump systems will generally be more resilient in the same fashion.

      The US uses the second deck as the damage control deck. Below that deck there are no penetrations like hatches going fore or aft. That's done to prevent progressive flooding and slow the spread of fire.
      On a commercial ship it isn't uncommon to find hatches all the way down into the main spaces for convenience of the crew rather than the "up and over" system of a warship.

      It isn't uncommon to find commercial ships being built with an expected service life. That is, x years of use in y conditions and then you scrap it somewhere like Bangladesh or Mauritius where there is no cost of doing so other than run it up the beach and walk away.



      Cruise ships really aren't much better. They aren't double hulled. They almost all have hatches that are below the top watertight deck. They have little pump and firefighting capacity. That's really nothing new either.

      The Costa Concordia is a good example. A large warship would probably have not capsized or sunk with similar damage.



      Flooding was rapid and progressive flooding was aided by open hatches low in the ship. The damage was the equivalent of about two modern torpedo hits.

      Commercial ships may also use lower grades of steel in construction as well as not be built to take shock as well.

      More later...

      Comment


      • #4
        Originally posted by T. A. Gardner View Post
        It varies depending on the country involved.

        The actual design of warships is usually predicated on one of two basic ideas around survivability of the ship:

        Three compartment, where the design allows for three major compartments or subdivisions of the ship can flood and the ship will remain afloat.

        The other is a 60% rule. The US uses this one. 60% of the waterline volume of the ship can flood to the second deck and the ship will remain afloat.

        As far as details, commercial designs don't take damage into consideration other than in terms of environmental safety. For example, following the Exxon Valdez and other accidents with tankers almost all are now double hull to prevent spills.

        With naval ships the layout of the electrical system is far more resistant and redundant than on a commercial ship. The system will generally have more capacity too.
        Small warships will have their distribution system split fore and aft port and starboard with a cross connect at some point (think of a Z or S configuration) along the length of the ship to maximize survivability of the some of the system after damage. They will have at least one emergency generator aboard too.
        On large ships a ring bus is used for maximum survivability.

        Firemain and pump systems will generally be more resilient in the same fashion.

        The US uses the second deck as the damage control deck. Below that deck there are no penetrations like hatches going fore or aft. That's done to prevent progressive flooding and slow the spread of fire.
        On a commercial ship it isn't uncommon to find hatches all the way down into the main spaces for convenience of the crew rather than the "up and over" system of a warship.

        It isn't uncommon to find commercial ships being built with an expected service life. That is, x years of use in y conditions and then you scrap it somewhere like Bangladesh or Mauritius where there is no cost of doing so other than run it up the beach and walk away.



        Cruise ships really aren't much better. They aren't double hulled. They almost all have hatches that are below the top watertight deck. They have little pump and firefighting capacity. That's really nothing new either.

        The Costa Concordia is a good example. A large warship would probably have not capsized or sunk with similar damage.



        Flooding was rapid and progressive flooding was aided by open hatches low in the ship. The damage was the equivalent of about two modern torpedo hits.

        Commercial ships may also use lower grades of steel in construction as well as not be built to take shock as well.

        More later...
        Most cruise ships were built before the 2009 IMO agreement so a lot of the above is now obsolete
        Human history becomes more and more a race between education and catastrophe (H G Wells)
        Mit der Dummheit kaempfen Goetter selbst vergebens (Friedrich von Schiller)

        Comment


        • #5
          Originally posted by MarkV View Post
          Most cruise ships were built before the 2009 IMO agreement so a lot of the above is now obsolete
          It really makes no difference. Building code is the same way. You get what you pay for. If the minimum is what you want you'll get it, you'll also get contractors that short sheet stuff, use substandard materials, hide flaws, and otherwise not meet even the minimum code.

          No difference with ships. Commercial ships are mostly going to be built to the minimum standard simply because they have to be profitable to the maximum degree possible.

          Comment


          • #6
            Originally posted by T. A. Gardner View Post
            It really makes no difference. Building code is the same way. You get what you pay for. If the minimum is what you want you'll get it, you'll also get contractors that short sheet stuff, use substandard materials, hide flaws, and otherwise not meet even the minimum code.

            No difference with ships. Commercial ships are mostly going to be built to the minimum standard simply because they have to be profitable to the maximum degree possible.
            Well possibly in the USA there may be cowboy outfits but generally the IMO is one of the few UN organisations that has some legal teeth and uses them.
            Human history becomes more and more a race between education and catastrophe (H G Wells)
            Mit der Dummheit kaempfen Goetter selbst vergebens (Friedrich von Schiller)

            Comment


            • #7
              Do you really think the UN can do squat about a freighter built in China and flagged in Panama or Liberia that has questionable, but would require a costly detailed inspection to prove, quality built in?

              It's just like the construction industry. If you aren't watching them like a hawk, willing to pay for quality, then they will short sheet you in a nanosecond.

              Comment


              • #8
                A major difference is in crew strength and training. Naval vessels are over-manned to allow for function despite casualties, and to allow the ship to fight while doing damage control and other essential tasks. Additionally, the navy requires many highly specialized personnel not found - or needed - on commercial vessels.

                Comment


                • #9
                  Originally posted by Mountain Man View Post
                  A major difference is in crew strength and training. Naval vessels are over-manned to allow for function despite casualties, and to allow the ship to fight while doing damage control and other essential tasks. Additionally, the navy requires many highly specialized personnel not found - or needed - on commercial vessels.
                  This is something naval ships have been catching up on. Many more systems today are automated than in the past. Crew counts are going down in an effort to reduce costs. Maintenance is being turned over to contractors more and more.

                  That may prove problematic in a shooting war, but that's yet to be seen.

                  I know that at least the USN has been moving to greatly update the detail on damage control charts for ships. In the "old days" these showed compartments and only the most major systems going through them. It was a real bear to do something like ensure all electrical power was shut down in a compartment for a fire and the like. Ventilation was the same way. Fires could and would travel through the ventilation system and it was often hard to isolate these.

                  Comment


                  • #10
                    Originally posted by T. A. Gardner View Post
                    This is something naval ships have been catching up on. Many more systems today are automated than in the past. Crew counts are going down in an effort to reduce costs. Maintenance is being turned over to contractors more and more.

                    That may prove problematic in a shooting war, but that's yet to be seen.

                    I know that at least the USN has been moving to greatly update the detail on damage control charts for ships. In the "old days" these showed compartments and only the most major systems going through them. It was a real bear to do something like ensure all electrical power was shut down in a compartment for a fire and the like. Ventilation was the same way. Fires could and would travel through the ventilation system and it was often hard to isolate these.
                    The major problem with heavily automated systems is that they have to work at all times. They cannot ever fail.

                    In the old days, any severe problems were overcome on warships by simply putting sailors in to do by hand what mechanical systems did before they were knocked out. There are many examples of ammo being passed hand to hand down a long line of sailors from a magazine in the bottom of the ship to the gun positions of deck to keep the guns firing, and communications being handled by lines of men who shouted commands all the way from the bridge to after steering.

                    The Navy is highly redundant for very good reasons.

                    Technology enables one to run an entire battleship from the bridge, but once the firing starts you had better have a lot of highly trained crewman on hand to deal with the inevitable problems and damages.

                    Comment


                    • #11
                      Originally posted by Mountain Man View Post
                      The major problem with heavily automated systems is that they have to work at all times. They cannot ever fail.

                      In the old days, any severe problems were overcome on warships by simply putting sailors in to do by hand what mechanical systems did before they were knocked out. There are many examples of ammo being passed hand to hand down a long line of sailors from a magazine in the bottom of the ship to the gun positions of deck to keep the guns firing, and communications being handled by lines of men who shouted commands all the way from the bridge to after steering.

                      The Navy is highly redundant for very good reasons.

                      Technology enables one to run an entire battleship from the bridge, but once the firing starts you had better have a lot of highly trained crewman on hand to deal with the inevitable problems and damages.
                      You don't have to tell me...

                      Sea story... Went to the George Philip right after 9/11. It was in Continental Marine's yard in San Diego under the Coronado bridge. The Navy was worried someone might try something from the bridge and wanted the ship moved. It had a number of serious electrical issues, hence Mr. expert shows up to fix them...

                      Anyway, one of the lessor problems was the automatic stability control didn't work, particularly the starboard unit. I was told by the Engineer that it was a "CO's interest item" to get it working.
                      So, I drug one of my (in the sense that I was now the senior electrician on board and in charge of that shop for the moment) junior PO's down to the compartment to fix it.
                      Got the manual and then fixed a few broken connections on input sensors. That left the MIMS card box full of crap to go through. I got a "suitcase" full of replacement cards and started trouble shooting the box. I replaced 4 cards and it was working.
                      The PO standing there says "Chief, you can't just replace those cards like that! You have to have the CO's permission!"
                      I looked at him and said "It f..king works now. Let me worry about the CO."
                      Went and found him. "Sir, the stabilizers work now. Had to replace these four cards (tossed on his desk). I was told I needed to inform you."
                      (note: Those cards cost in excess of $1000 total...)

                      The XO was begging me to stay on after I fixed all their FU'd and crap.

                      The one I found jaw dropping was the flight deck lighting system. The intensity of the lamps was set using a series of variac's (variable AC voltage rheostats) run by little DC drive motors. It was the most Rube Goldberg, half @$$ed, designed by some idiot system I've ever seen...

                      Comment


                      • #12
                        Quick note without chiming into the discussion is that some navies take into account different ice states when building ships. For example Finnish Navy Minelayers are the biggest boats we have and they have pretty good ICE-1A classification which means that ship can operate all around the year, but requires some help from ice breakers during hard winters.

                        The thing how I see is that anybody with even littlebit of maritime industry and shipbuilding can make a warship of adequate quality. But it requires quite lot of skill on how to make the ship last long enough the wear and tear. Then we have to take in account all the electronics and weapon systems, we can't just bolt 40mm Bofors on deck and call it a day.
                        From Devastation - Knights Twilight Warhammer 40,000 Quest
                        Rear Admiral Sander Van der Zee, Commander of Dutch Far East Theatre
                        "There is never enough firepower!"

                        Comment


                        • #13
                          Originally posted by T. A. Gardner View Post
                          It varies depending on the country involved.

                          The actual design of warships is usually predicated on one of two basic ideas around survivability of the ship:

                          Three compartment, where the design allows for three major compartments or subdivisions of the ship can flood and the ship will remain afloat.

                          The other is a 60% rule. The US uses this one. 60% of the waterline volume of the ship can flood to the second deck and the ship will remain afloat.

                          As far as details, commercial designs don't take damage into consideration other than in terms of environmental safety. For example, following the Exxon Valdez and other accidents with tankers almost all are now double hull to prevent spills.

                          With naval ships the layout of the electrical system is far more resistant and redundant than on a commercial ship. The system will generally have more capacity too.
                          Small warships will have their distribution system split fore and aft port and starboard with a cross connect at some point (think of a Z or S configuration) along the length of the ship to maximize survivability of the some of the system after damage. They will have at least one emergency generator aboard too.
                          On large ships a ring bus is used for maximum survivability.

                          Firemain and pump systems will generally be more resilient in the same fashion.

                          The US uses the second deck as the damage control deck. Below that deck there are no penetrations like hatches going fore or aft. That's done to prevent progressive flooding and slow the spread of fire.
                          On a commercial ship it isn't uncommon to find hatches all the way down into the main spaces for convenience of the crew rather than the "up and over" system of a warship.

                          It isn't uncommon to find commercial ships being built with an expected service life. That is, x years of use in y conditions and then you scrap it somewhere like Bangladesh or Mauritius where there is no cost of doing so other than run it up the beach and walk away.



                          Cruise ships really aren't much better. They aren't double hulled. They almost all have hatches that are below the top watertight deck. They have little pump and firefighting capacity. That's really nothing new either.

                          The Costa Concordia is a good example. A large warship would probably have not capsized or sunk with similar damage.



                          Flooding was rapid and progressive flooding was aided by open hatches low in the ship. The damage was the equivalent of about two modern torpedo hits.

                          Commercial ships may also use lower grades of steel in construction as well as not be built to take shock as well.

                          More later...

                          HMS Nottingham had a similar navigational oops and suffered some serious damage, and her cover yaws by no means assured, but the ship survived the incident.

                          https://en.m.wikipedia.org/wiki/HMS_Nottingham_(D91)

                          The damage pics are impressive, can't post them on this stupid iPad,
                          One accurate measurement is worth a thousand expert opinions - Admiral Grace Hopper

                          "The eunuch should not take pride in his chastity."
                          Wu Cheng'en Monkey

                          Comment


                          • #14
                            Originally posted by Senorankka View Post
                            Quick note without chiming into the discussion is that some navies take into account different ice states when building ships. For example Finnish Navy Minelayers are the biggest boats we have and they have pretty good ICE-1A classification which means that ship can operate all around the year, but requires some help from ice breakers during hard winters.

                            The thing how I see is that anybody with even littlebit of maritime industry and shipbuilding can make a warship of adequate quality. But it requires quite lot of skill on how to make the ship last long enough the wear and tear. Then we have to take in account all the electronics and weapon systems, we can't just bolt 40mm Bofors on deck and call it a day.
                            The Russians do that too. Their naval ship's hulls have thicker plating. You don't notice the sort of "dishing" you see on US vessels as a result. That's due to their expected use in waters with ice and in rougher weather.

                            Comment


                            • #15
                              Originally posted by MarkV View Post
                              Here's a more recent version of this excellent document:
                              http://139.30.101.246/ISSC2012/image...l2-com-V.5.pdf
                              Battles are dangerous affairs... Wang Hsi

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