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16-in Guns vs Hard Targets : A Reality Check

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  • #91
    Originally posted by Shipwreck View Post
    A mere look at the difference between the *figures* you came up with using your *method* (i.e. 24.9 MJ for ERGM) and the so-called *available energy on target) given in the NRAC chart (i.e. 7 MJ for ERGM) should be sufficient to question the validity of your *method* and the *results* you came up with.

    Well, the NRAC chart is from the rail gun folks. The 24.9 is based on the actual energy content of the explosive used for ERGM which is 92.5% HMX.


    There is MUCH MORE to effectiveness than just kinetic and chemical energy...

    In fact, suggesting that effectiveness is proportional to the sum of kinetic and chemical energies is nothing but MICKEY MOUSE PHYSICS...

    Didn't know old Mickey got his degree in physics. And yes, the "mickey mouse physics" as you call it, comes in to play when folks are designing weapons. Please tell those folks to stop using their mickey mouse physics.



    It is such a BLANKET STATEMENT that you've so far failed to quantify what you meant by *far greater*...

    Well, the above numbers equate to *far greater*.

    Furthermore, I did ask you to submit the empirical evidences that would support your claim and what you've posted so far has nothing to do with empirical evidences...

    I will do that shipwreck, I will try and look around for more info.

    Well, you have many more google links than I. You have, so far, been trying to point out the negative side. How about posting both sides of the story.

    Whenever time permits, I'll be posting such data on KOREA and VIETNAM. And yes, I mean empirical evidences (i.e. based on actual observations).

    Yes, please do. Just include all of it, not just bits and pieces just to support your cause.

    You're kicking in open doors, hence the appropriate emoticon...


    Thanks to zen again.

    Comment


    • #92
      Originally posted by SteaminDemon View Post
      All of them came in handy and helped save lives.
      Where ? When ? Source(s) ?

      A prominent military-centric forum like WAB is no place to recite catechism...

      Comment


      • #93
        Originally posted by SteaminDemon View Post
        Well, the NRAC chart is from the rail gun folks. The 24.9 is based on the actual energy content of the explosive used for ERGM which is 92.5% HMX.
        So you pretend to know better than the people who wrote this report (the slide regarding comparative energy on target is on page 31 of this report) ?

        I think NOT.

        Originally posted by SteaminDemon View Post
        Didn't know old Mickey got his degree in physics.
        The point was precisely that Mickey Mouse knows sh*t about physics, but would nevertheless pedantically invoke its laws to justify his buffonish claims. ;)

        Originally posted by SteaminDemon View Post
        Well, the above numbers equate to *far greater*.
        What is *far greater* ? What does *far greater* mean ?

        Originally posted by SteaminDemon View Post
        Well, you have many more google links than I.
        You may not have noticed, but most of the data posted in this thread come from books and official reports...

        What are your sources ?

        Originally posted by SteaminDemon View Post
        Thanks to zen again.
        I don't quite see how Zen meditation can be of any help in the topic being discussed, but hey, whatever...

        Comment


        • #94
          Shipwreck,

          I am going to go enjoy my fourth of July. Have a Happy fourth of July. I'll be back to respond another time though.

          Happy 4th ALL!
          SteaminDemon:)

          Comment


          • #95
            Originally posted by SteaminDemon View Post
            I'll be back to respond another time though
            Don't feel obliged to respond (especially if you've got nothing interesting to say )...

            Originally posted by SteaminDemon View Post
            I am going to go enjoy my fourth of July. Have a Happy fourth of July.
            Happy 4th to you. :)

            Comment


            • #96
              Vietnam vs Korea : Relative Effectiveness of 16-inch vs 5-inch

              Relative Effectiveness of 16-inch rounds compared to 5-inch (assuming probability of a hit is independent of range) :

              Korea (average, all targets) :
              * 5-inch (38-cal) : 1
              * 16-inch : 1.79

              Vietnam (average, all targets) :
              * 5-inch (38-cal) : 1
              * 16-inch : 3.60

              Relative Effectiveness of 16-inch rounds compared to 5-inch (assuming probability of a hit is inversely proportional to square of range) :

              Korea (average, all targets) :
              * 5-inch (54-cal) : 1
              * 16-inch : 9.80

              Vietnam (average, targets = bunkers + area + interdiction, i.e. 73.5% of total 16" ammunition expanded) :
              * 5-inch (54-cal) : 1
              * 16-inch : 9.84

              Sources : see post #34

              Comment


              • #97
                What's wrong with Mickey Mouse Law of Physics...

                Originally posted by SteaminDemon View Post
                16" Mk-13 HC:

                Available chemical energy 154.8 LB, 3,789 Joules per gram for explosive D = 264,334,584 Joules. At maximum range @ 1552 FPS it gives the projectile 96,452,984 Joules of kinetic energy. Total energy (both chemical and kinetic) at the target is about 361 MJ
                Let's take the data for Korea :

                1. 16" Mark-13 HC

                Kinetic Energy :

                Per OEG Study 506, the average range for 16" missions in Korea for the period considered was 22,700 yards.

                At 22,700 yards, striking velocity for the Mark-13 HC projectile is 1,519 fps, i.e. 463 mps (with IV = 2,690 fps).

                The mass of the Mark-13 HC projectile is 1,900 lbs, i.e. 862 kg.

                Kinetic energy is therefore equal to : 1/2 * 862 * 463^2 = 92 MJ

                Chemical Energy

                Bursting charge for the Mark-13 HC is 154 lbs, explosive D.

                Assuming 3,789 Joules per gram for explosive D, this yields a chemical energy of 264 MJ.

                2. 5" Mark-35 AAC

                Kinetic Energy :

                Per OEG Study 506, the average range for 5" missions in Korea for the period considered was 9,700 yards.

                At 9,700 yards, striking velocity for the Mark-35 AAC projectile is 965 fps, i.e. 294 mps (with IV = 2,500 fps).

                The mass of the Mark-35 AAC projectile is 55.18 lbs, i.e. 25 kg.

                Kinetic energy is therefore equal to : 1/2 * 25 * 294^2 = 1 MJ

                Chemical Energy

                Bursting charge for the Mark-35 AAC with PD fuze is 7.55 lbs, explosive D.

                Assuming 3,789 Joules per gram for explosive D, this yields a chemical energy of 13 MJ.

                3. Mickey Mouse Laws of Physics

                Based on Mickey Mouse Laws of Physics, total energy (both chemical and kinetic) at the target is :

                * 92 + 264 = 356 MJ for the 16" Mark-13 HC
                * 1 + 13 = 14 MJ for the 5" Mark-35 AAC

                Mickey Mouse is therefore tempted to conclude that relative effectiveness of 16-inch rounds compared to 5-inch is ~25:1.

                4. Reality Check

                Per OEG Study 506, relative effectiveness of 16-inch rounds compared to 5-inch is somewhere between ~2:1 (assuming probability of a hit is independent of range) and ~10:1 (assuming probability of a hit is inversely proportional to square of range).

                IOW 2.5 to 12.5 times less than what Mickey Mouse Laws of Physics predict.

                5. Conclusion

                Mickey Mouse Laws of Physics...
                Attached Files
                Last edited by Shipwreck; 04 Jul 08,, 23:42.

                Comment


                • #98
                  Originally posted by Shipwreck View Post
                  Don't feel obliged to respond (especially if you've got nothing interesting to say )...



                  Happy 4th to you. :)
                  Hey Shipwreck. :)) Just a quick reply (until I dig up more things) Thanks for the new info you posted. The 16 Inch will hit harder and do more damage than the smaller projectiles, So, in essence, the 16" projectile will hit harder than any of those projectiles on any day (proven by physics). You can't deny that. Accuracy and other things are a factor, and I am not blind to that.


                  I had more graphs, and other info but lost them between computers (virus on old comp). I am no weapons expert, someone like Mr. Okum is and would be able to explain these things way better than I. However, keep on posting, just not one sided. You have not posted one thing about the lack of effectiveness of the 5" or 8" at all, and there are reports that explain that which I am sure you have;).

                  Comment


                  • #99
                    Bunkers in Vietnam : 16-inch vs 8-inch vs 5-inch

                    Data for Target Type = BUNKERS
                    Basis = Successful Missions

                    Relative Effectiveness of 16-inch rounds compared to 5-inch (assuming probability of a hit is independent of range) :

                    * 5"/54 : 1
                    * 8"/55 : 1.35
                    * 16"/50 : 2.63

                    Relative Effectiveness of 16-inch rounds compared to 5-inch (assuming probability of a hit is inversely proportional to square of range) :

                    * 5"/54 : 1
                    * 8"/55 : 1.61
                    * 16"/50 : 6.08

                    Source : see post #34
                    Last edited by Shipwreck; 09 Jul 08,, 23:30.

                    Comment


                    • Erratum

                      Originally posted by Shipwreck View Post
                      Relative Effectiveness of 16-inch rounds compared to 5-inch (assuming probability of a hit is independent of range) :

                      Korea (average, all targets) :
                      * 5-inch (38-cal) : 1
                      * 16-inch : 1.79

                      Vietnam (average, all targets) :
                      * 5-inch (38-cal) : 1
                      * 16-inch : 3.60

                      Relative Effectiveness of 16-inch rounds compared to 5-inch (assuming probability of a hit is inversely proportional to square of range) :

                      Korea (average, all targets) :
                      * 5-inch (54-cal) : 1
                      * 16-inch : 9.80

                      Vietnam (average, targets = bunkers + area + interdiction, i.e. 73.5% of total 16" ammunition expanded) :
                      * 5-inch (54-cal) : 1
                      * 16-inch : 9.84

                      Sources : see post #34
                      Data for Korea = 5-inch (38-cal)
                      Data for Vietnam = 5-inch (54-cal)

                      Sorry for the typo in original post.

                      Comment


                      • Bombardment of Brest, 24 August 1944

                        Battleship Warspite by V.E. Tarrant :

                        During August 1944, the Americans were investing a powerful force of 40,000 German troops which wa cut off and squeezed up in the tip of the Brest peninsula.

                        The lynch-pin of their defenses was a girdle of old French forts dating from the time of Louis XIV (1774-93) and casemates armed with heavy guns.

                        In the confined space of the peninsula, the Americans could not take these fortifications, which commanded all land approaches, except at a heavy cost in casualties.

                        Warspite, therefore, was called upon to silence them with her 15-inch guns.
                        Attached Files
                        Last edited by Shipwreck; 19 Sep 08,, 23:20.

                        Comment


                        • Bombardment of Brest, 24 August 1944 - Targets

                          Battleship Warspite by V.E. Tarrant :

                          The control station ashore gave five targets to be engaged; fifty rounds to be fired on each in thirty minutes. Firing to be completed in 2.5 hours, before the assault by the attacking troops commenced.

                          Target #1 : Keringar 11-inch gun battery (called Graf Spee by the Germans). Target was found with four ranging salvoes. Spotting aircraft reported near misses on all gun turrets. Fifty-seven rounds expended.

                          Target #2 : Les Rospects 6-inch gun battery in casemates. Range 29,000 yards. Eight salvoes were fired before firing for effect. All salvoes after the fifth were in the target area. Twenty-two salvoes were fired - 47 rounds expended.

                          Target #3 : Toulbroch Fort, including two batteries running 1,000 yards to the west. Range 32,000 yards. Target was found with two salvoes. Eleven salvoes were fired - 32 rounds expended.

                          Target #4 : Minou Fort. Range 31,000 yards. Target was found in three salvoes. Several salvoes were not seen owing to smoke and dust over target area. Eighteen salvos were fired - 51 rounds expended.

                          Target #5 : Montbarey Fort. Range 32,000 yards. Target was found in four salvoes - 26 rounds expended.

                          Comment


                          • Bombardment of Brest, 24 August 1944 - Keringar

                            Keringar Battery (aka MKB Graf Spee of 5/MAA 262) in Lochrist near Brest was armed with 11-inch SK L/40 naval guns.

                            Originally built for the Braunschweig and Deutschland pre-dreadnoughts, the SK L/40 used as coast defense gun fired a 626-lb projectile to a maximum range of 30,250 yards.

                            Three of the four guns were in open pits, and only one in a large casemate shown in the pics below :
                            Attached Files

                            Comment


                            • Bombardment of Brest, 24 August 1944 - Targets

                              Top to Bottom :

                              1. & 2. : Les Rospects

                              3., 4. & 5. : Toulbroch
                              Attached Files

                              Comment


                              • Bombardment of Brest, 24 August 1944 - Results

                                Battleship Warspite by V.E. Tarrant :

                                It was while Warspite was engaging Montbarey Fort, that the control station ashore made the signal at 17:45 : "Afraid your time is up, cease fire".

                                Simultaneously with the receipt of this signal, came the first reply by enemy. Huge fountains of sea-water rose near Warspite from 11-inch shells falling short, fired by the Keringar battery.

                                Ten salvoes were fired at Warspite, three of which fell so close on the starboard bow and beam, that splinters from the shells hit the funnel, motor-cutter and starboard HA director.

                                (...)

                                In total, Warspite had fired 213 high-explosive and armour-piercing shells. Results were disappointing. Although one of the forts and a few of the batteries were silenced, others survived practically intact, and were able to put up a stiff resistance to the attacking troops.

                                Comment

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