NEW COURSE - Naval Vessel Design

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This is a tentative outline for what SHOULD be in such a course - it is not fully developed into what WILL be in the course. As a result, there is too much content here - too many topics to reasonably cover in one semester.

Also: A large number of these topics were 'harvested' from Professor Al Brown's naval engineering course syllabi from Virginia Tech. Thank you Professor Brown.

Naval Vessel Design

A course that attempts to at least acquaint the 'traditional' naval architect with the particular challenges of naval design. The theme is that the requirements of naval missions are not merely 'cargo' to the ship, but are in fact as stressing to the design as are the requirements of hydrodynamics or structural loads. As a consequence, the hardest part of the design task is to measure the ship's effectiveness: If design is decision-making, then how do you know if you have made the right decisions? A discussion of naval MoEs will form at least 50% of the course content.

In order to understand the missions and MoEs, it is also necessary to understand the peculiarities of naval systems, which includes not merely the shipboard system but hte acquisition and operational systems in which they function. This course will study concepts and methods for the description, analysis and integration of various naval ship systems into the total naval ship design. The course will place particular emphasis on system analyses and phenomena that have applicability across all naval engineering disciplines including ship system arrangements, system reliability, maintenance, modularity, system power, shock and loads, and system survivability.


Setting the Stage

[The following material was provided to me by a source who requests to remain anonymous. I think that it is actually an apt introduction to the complexity of warship design.]

Floki’s Notes

This talk was given by Floki the One-Eyed at the annual meeting of A.S.N.E. (Association of Survivors of Norse Expeditions), held in the Mead-Hall at Vasingsvik, February of 1011. The audience consisted of active duty and retired warriors, a number of the People that Handle the Gold, and artisans of many crafts and traditions.

As everyone knows, in the middle of the talk Floki was dragged out of the hall and thrashed within a hair’s breadth of his miserable life. Those of us who were there have never been able to recall exactly why this was done, because there were so many possible reasons, and because we were all very far gone with strong drink. We do remember the people in the front row who insisted that Floki be soundly beaten, and started in on him with their own hands. Be that as it may, these are, close enough, the words of Floki the One-Eyed before we pounded him.

“It seems to me that we’ve been struggling for many years to turn war into just another business. We’ve not succeeded. Our Wise-Men tell us that it’s not appropriate to treat the conduct of a game in the same way as a decision-theoretic problem, whatever that means. On the other hand, the Wise-Men also tell us that some parts of a fight can be treated ‘elegantly’ using a dynamic-game theoretic approach. But nobody really understands the Wise-Men either way. Also, we’re not sure what a dynamic game is, and what they mean by ‘elegant.’ We do but sit in a circle and listen to them, or at least we pretend to if there’s enough time, because the mere act of pretending to listen makes us appear wiser than we are.

“But since no Wise-Men are here right now, let us be realistic. The making of warrior-stuff is not the province of Wise-Men. They may think it is, but it isn’t. Not when we start spending the gold for it, nor when we start to draw the plans for building it, nor when we start cutting the metal for it. To speak plain, the Wise-Men’s pronouncements are not truly the heart of this matter.

“Why are we having so much trouble making war into just another business? I will tell you. People, even people of low station and miserable means, behave differently from inanimate objects or helpless animals. Have we not seen this, every one of us? The warriors I’ve known, even the fiercest, men who laugh in battle, even they care about life and death. More than a piece of metal cares whether I cut it at an angle or hammer it on the end to put a point on it. But this is what I have to say. Those who have grown out of the fighting business and gotten into the warrior-stuff acquisition business have their own way of showing their preferences about life or death. They write requirements, those of them who know how to write, which isn’t many of them. As for the rest, they just try to tell us in words what they need in order to fight, and we try to give them what they ask for. Can it be that this is so difficult?

“Well, it is. And here is what I see: as it is for fighting, so it is for the things we make for fighting. The way we plan, and build, and buy our swords and spears, our bows and arrows, our shields and helmets and armor, our war horses, our fighting stuff of all kinds – well, our way rarely goes far without a rough stretch. The way we’ve always done a thing stops working. It takes us half the day to notch and glue the fletching on an arrow, when it used to take hardly any time at all. We have accidents we never had before. The gold runs out and they’ve not finished paying us for our work. Things they told us they must have, will have, or our heads should pay for it, they tell us they need no longer.

“Worse still, our stuff doesn’t work as it’s supposed to, as it always did aforetime. Actually, it didn’t always work, but because days that are gone fade into golden haze as we grow older, we think it did always work, and we tell each other so. That doesn’t matter. What matters is that we are humiliated in public. You craftsmen know what I’m talking about Your spear won’t throw straight, your bow keeps breaking arrows instead of shooting them, and your shield won’t turn a blade any better than a piece of rotten canvas. Can it be that you’ve forgot some secret art? Maybe. But maybe it’s because the people who tell you what they want have lost the secret art of telling. That, or maybe they’ve become a-feared to tell you. They are eager to put aside that care, and they want you to tell them.

“And what about you? You have lost the secret art of listening. So listen to me, now, if you can. The more innovative your product is, and the more of a ‘revolution in military affairs’ it might be said to offer, the more this seems to happen and the worse off you are. Deny it if you can, you eaters of vegetables!

“These things have occurred in our civilian and commercial stuff, too. Well do I remember the day I said to Thorberg the Skarfhogg – I said, ‘Thorberg, you ought to think about putting your rudder on the sternpost, with iron hinges like a door, instead of just hanging it over the side on that knotted piece of rope like you’ve always done.’ Why, if looks could kill, the look Thorberg gave me then would have wiped out me, my sons, and all the line of my ancestors back to the beginning.

“Let it be said that Thorberg had his suspicions in this: I’m a smith, after all, and he knows well enough that I happen to make iron hinges, too. But let that go.

“Still, I tell you that warrior-stuff is especially troublesome. To understand better what the warrior needs, or even what he’s saying when he speaks, you craftsmen, and you People that Handle the Gold, too, all of you, you owe it to yourselves to try to understand war better. It is not comfortable to do this, I know, especially for those who aren’t warriors themselves. Even for those who have been warriors, but so long ago they’ve forgotten what it is to be young and strong and berserk. We need to study the language of the warriors because once they study our language too much they become more like us. That can’t be helped, I don’t think, but it is perilous.

“Remember, it is our job, artisans and craftsmen, and you People that Handle the Gold, too, to understand warriors. It is not their job to understand us. They have their own job. Would you wish to trade jobs with them? Some of you, probably. I know which ones you are. But for most of you, not likely. Not in this life.”‘‘

Floki’s Propositions. ‘‘

“What makes warrior-stuff unlike the things we make for every day? The propositions I’m about to give you are without proof, that I know of. So you have to think for yourself whether they’re true or not. But this is the main idea: warrior-stuff, from the planning to the building to the thing itself, is different from other things, different in kind. Why so different? Because what you do with war-stuff is different from what you do with all other things. There, I’ve said it! Deny it if you like, but these propositions are what I believe about war.” ‘‘

The Primacy of Hitting. “War is about fighting, and fighting is about hitting. I’ve learned to use a fancy word for this – I once heard it from a Wise-Man. ‘Floki,’ he said, ‘Attrition is in general what happens when you hit. Attrition means wearing down: wearing down of resources: material, people, houses, boats, strength, presence of mind, or any other necessity in a fight.‘ ‘‘

“Being who we are, we usually take attrition to be physical incapacitation, depletion, or destruction. In our history it has most often been that, and isn’t it the truth, even if it’s Floki as says it? But not all our resources are physical, and so not all attrition has to be physical, either. We can wear down another man’s patience, his information, his political connections, his popular support, or his ‘morale.’ That’s another word I heard from a Wise-Man, and I think it means mostly the willingness to keep fighting instead of quitting or running away, which a man might do at a certain point if he had any sense in his head, before he has it broken for him. ‘‘

“Listen. The ability to cause attrition is the essence of fighting, and therefore it’s the soul of warrior-stuff. Don’t let anybody fool you. It is ‘hitting power’ we are always after. In their zeal to be up to date, and maybe because they’ve been off gallivanting in foreign parts, in the East somewhere, maybe, some of the Wise-Men want to call this same thing, this ability to cause attrition, ‘firepower.’ I’m not sure why they’d ever want to call it that, whether it describes actual fire or not. But it doesn’t matter what word you use for it if you know what it means. ‘‘

“Now ‘hitting power’ isn’t simple; it has in it a whole world of different abilities to wear different things down. But this much is sure: hitting power is properly measured not in the weapon store, or at the shoulder or the hand, or off the bowstring or the end of the throwing stick. It is properly measured on the target. Only on the target, because that is where the attrition you want actually happens. So, to me, hitting power includes the eye that tells the hand how to hit. I know how important that is, none better, because I have only one left. ‘‘

“The target means the one you were actually trying to hit, usually; that’s no more than common sense. But don’t forget that sometimes you can miss that one and hit the man next to him. That’s attrition, too, don’t forget. If it doesn’t do anything else it’ll remind that other fellow not to stand so close, and that can work to advantage, too. Sometimes you have to do a thing piece be piece. But a man harvesting wheat uses a scythe, he doesn’t cut off one stalk at a time. So remember that hitting power can include both the strength of the hit at the exact place of the hit, and also the distance around that exact place where there’s still enough damage happening to be important. ‘‘

“Also, remember that hitting first is a good thing. It can be just what it takes to win. But also keeping on hitting can be a good thing, and that, too can be just what it takes to win. It depends, perhaps, on how many are coming against you, and when they will come. If you had a bow that could shoot a dozen arrows at a time, but only a dozen arrows in your quiver, would you shoot all of them on the first volley? Maybe yes, and maybe no. Meanwhile, a man with a bow like that might also want more arrows. The time it takes to begin causing attrition, the rate at which you can cause attrition, and the total amount of attrition you can cause, given enough time, all of these are important, but which is most valuable depends on the kind of fight you are in. Other things may determine what kind of fight that will be, but more of that in a moment.’‘

“Now I see in the back of the room that we have some seeing-stone and horn makers here, too. You fellows, I know, are working on ways that you can aim an arrow using nothing but what you can see in your stone, or hear in the echoes of the noise from your horn. Good luck and bless you for it. But when you can do that, especially with the way some of you people shoot, I mean to include your ways of ‘seeing’ in the same sense as an eye. ‘‘

“On the other hand, hitting power may not have to be applied for it to have an effect on an opponent’s behavior. On occasion hitting power might accomplish something merely by existing (or being perceived), as a scare. But without hitting power of some kind, fighting isn’t fighting. ‘‘

“Hitting power, depending on who we want to hit and how we want to hit, can be made up from every weapon we have in this world, whether it be of the arm, the mouth, or the mind. But here is a lesson in it. Once it’s decided and spoken what kind of a thing we want, if it takes too long to plan it and build it and pay for it, and get it ready, then time and the enemy may well take away the thing you’d decided to hit, and put something else in its place that you hadn’t thought much about. ‘‘

“So, you warriors, be a little bit careful about asking us in the crafts for things that are too special. They may not be worth as much as you originally thought for as long as you thought. Worse, by the time you get them they may not even be worth the gold you’ve already spent, and you’re still not finished paying.”‘‘

Mobility. “Only things that can move can achieve the advantages of both place and time. That is, a place and a time where you’re most likely to get a favorable exchange of attrition: preferably, all the attrition on the other fellow, and little or none on you. It’s an easy thing to imagine mobility as speed, mostly, as a man on a horse is able to move faster than a man on foot. An easy thing, but a wrong one. Mobility means more than speed alone, and even speed is a lot more complicated than it sounds. Speed over what distance or for how long, or over what kind of ground or water? ‘‘

“Still, the principle is that mobility can give the initiative, and from the initiative come many other good advantages. The ability to concentrate hitting power at a place and time where it’ll do us the most good: that’s important. Also, to avoid a concentration of the enemy’s hitting power, if we can see it in time. And best of all, to achieve surprise. ‘‘

“Mobility means being able to move fast enough, for far enough, so that we have time to be properly set, in the place where we want to fight, and the enemy doesn’t have time. Then he has to fight, maybe, where he doesn’t want to fight. On the other hand, where an opponent is strong enough to be at a great advantage, maybe it’s also good to be fast enough for long enough to stay away from him. ‘‘

“But can you have too much mobility? That’s a good question. You can ask for too much, if it takes away from something else you want even more. Comes to my mind old Gunnar, the horse-breeder. When Sigurd asked him to breed up a horse with those extra-long legs, just so Sigurd could wade in from his ship out in deeper water. And he could. Very impressive Sigurd was on that horse. But that horse fetched up lame as soon as he came out of the water. Sigurd never made a penny with that horse, and no more did Gunnar. ‘‘

“Here’s another one for you, though. Does mobility include being fast enough to evade the sweep of a sword or the thrust of a spear? Does it mean being able to run or ride faster than an arrow? We will have to think about that. Be patient.”‘‘

Survivability. “Using hitting power when an opponent has no power to hit back is a luxury, apart from any misgivings we might have about doing massacre, and it’s a sad but true thing that many men have no such misgivings. But when hitting power is coming back at us in return, as usually happens in a fight, or we wouldn’t have any enemies worth fighting, why, then, the ability to stand up to it becomes a matter of some concern. I’ll call that ability ‘survivability,’ another word I heard once from a Wise-Man, though I’ve heard it called other things, long ago, by my own father. Of the words of his on this subject that I choose to repeat in polite company, my favorite is “steadfastness.” That just means the ability to ‘hold to one’s place.’ ‘‘

“The principle is that survivability furnishes enough time in which hitting power can be delivered to an opponent, in spite of the hitting power he’s trying to put onto you. So you should be able to see right away that the product of your hitting power and your survivability means something.’‘

“Like hitting power, survivability is made up of a number of different things: reducing the likelihood of being hit, reducing the effects of an enemy’s hitting power, and increasing the ability to restore our own hitting power and mobility (and maybe our survivability, too) even after we’ve been hurt.’‘

“Reducing susceptibility to being hit, ah, that is a lovely gift isn’t it? If I’d had more of that gift I’d still have both of my eyes. Perhaps if I’d drunk less I’d have had the sense to see that blow coming, and maybe I’d have stood back a little bit, or ducked. ‘‘

“It is not easy, but it can be done. For one thing, susceptibility can be reduced by having better awareness of what’s going on all around, as I should have had when I was young. So keeping our wits about us, and our eyes and ears sharp, and our minds awake instead of walking around half asleep, asleep and dreaming. Now those aren’t necessarily things we craftsmen can help with very much, if a warrior can’t stir himself up to pay attention. But there are things we can do. You makers of seeing stones, horns, and drums, take note. I’m told that by putting dried peas on the head of a snare drum on the ground you can hear horses galloping on frozen ground a long way off. That’s a good thing to know. ‘‘

“For another, susceptibility can be reduced by hiding and sneaking, and hitting from behind without a word of warning. I don’t hold with those things much myself, being old-fashioned. A plain road for me, though it lead through a hedge of swords. But in this world, under this sun, war is not about being fair. It is about taking advantage and getting it done. ‘‘

“For a third, susceptibility can be reduced by smoke and bright lights and mirrors and straw dummies of warriors standing on the walls of a stockade (taking arrows that could have been aimed at us) and other such deceptions and trickery.’‘

“Reducing vulnerability to the enemy’s hitting power? This is not so hard to understand. We swordsmiths, and shield-builders, too, this is where a good part of our business is. A sword, be it ever so sharp and well-balanced, will do the hand that wields it little good if it be broken at the first clash. So unless it be for use only on the defenseless, which is an unworthy thing for a swordsmith even to think about, a blade must be strong enough as well as sharp enough and handy enough. ‘‘

“Shields and helmets and armor we know of, but there is this, and meaning no disrespect for those who build such things for their livelihood: if a man’s shield or armor is so heavy that he can’t move, or can’t use his sword rightly, what then? How much weight, then, is to be shield and armor, and how much sword? And how much horse, for that matter? All good questions, and if you think it’s easy to come by the right answer then I have some advice for you: think some more. And while you think remember this well: the blade your opponent carries and intends to use on you is as important as what you’d like to do to him with yours.

“Now, will an archer in padded cloth on a pony beat a full-armored man with a lance on a heavy horse? Maybe, and maybe not. It depends. And on what does it depend, besides good fortune? Why, surely it depends on the armor, and the bow, and the arrow, too, and the range, of course, always the range. And the range depends, often as not, on the lay and shape of the ground where we fight. So. To be able to take most advantage of that ground we have to get there first, and we’re back to mobility again.

“A battle depends on numbers, too, there’s no point denying it. But it isn’t all in numbers. Haven’t we been there, some of us? Numbers sometimes count for less than people might think. Sometimes men can get packed in so tight they can’t even take a decent swing, or get into the fight properly at all. But numbers still can count plenty; just remember what I said about attrition.

“But you know, numbers isn’t usually a question for us craftsmen, except when we come to talk about how much our stuff costs. If it didn’t depend on numbers and the ground, then maybe we’d all of us fight the same way all over the world. And what fun would there be in that? But that’s for another talk.”

[Editor’s note: Floki apparently wanted to hold a seminar on force structure, but the people in the front row fixed it so he never did.]

“There are some subtleties to be found between mobility and survivability. What do you say about being agile enough, fast enough, or high-jumping or deep-diving enough, like, not to get hit? Not that it makes much difference what the words are, but it’s worth thinking about when you compare different kinds of warrior-stuff. It might be convenient to think of agility as a special kind of mobility, rather than throwing it into survivability all lumped up. It doesn’t really matter, except for this: if you’re on foot, the things you jump with are pretty much the same things you run with. But if you ever have to discuss mobility and survivability in the presence of a Wise-Man, he’ll perceive that you have thought about it, and are no one to be trifled with.

“And what about recoverability? Well, we can all agree that it’s important not to bleed to death. But it’s even more important not to bleed to death while you can still hit! It’s a shame if this happens just because you don’t have anything to bind yourself up so you can go back to work. Say a strip of cloth and a leather strap to fix up the mechanics of nature.

“Now that I’m thinking on it, although it is not pleasant to think about, survivability has another use, too. A man who can’t even hit any more can still draw attrition away from others who can. It’s only human nature to go after a sure thing sometimes. And there are a lot of men who’d prefer to face a weaker opponent than a stronger, given the choice, even if it’s not necessarily the best thing to do to win a battle. So being more recoverable might at least let you sell your life for a higher price.”

Other Attributes. “Before I go any further, this is a place to say that there are other important things to the warrior besides hitting power, mobility, and survivability. Among these, the things we most often argue about are reliability, maintainability, and availability. These things the Wise-Men tend to call the ‘ilities,’ which I used to think was just a way to mispronounce “ill at ease.” Sometimes, now, we just call them RM&A.

“RM&A is important, very important. We know that. If a bow only shoots eight times out of ten, and two times out of ten, for no reason at all, it just lets the arrow stay on the string or drop onto the ground, why, you might come to hate that bow like poison. On the other hand, suppose that same bow, when it does decide to shoot, is more deadly at long range than anything else you have on the wall. What then? It may not be obvious, but you have to think about this problem as a matter of exchange of attrition. That bow might be fine for taking long shots. But perhaps you’d be glad to reach for something else when an enemy comes too close. Again, you might be properly suspicious of my motives. I make swords. You might be willing to trade.

“And then there’s safety. It may sound strange to talk about safety when you’re going into a fight, but it still has a meaning. And don’t forget that we practice and train, too, and it’s a shame to get hurt doing that. So suppose you have a stand of arrows that all shoot wonderfully well, straight and far, when they shoot. But every now and then one of them splits right up the shaft and leaves you with feathers and little splinters of wood sticking out of your face. I little doubt how you’d take to those arrows, and what you might say to him that made them.

“But here is the lesson in it. Arguments about RM&A, or about safety, don’t change the fact that the warrior is in the special business of applying hitting power – with mobility and survivability to help him apply it. RM&A is about whether a warrior can count on his stuff to work when it’s needed, and that’s about how things are made and supported. But I could just as well talk about the RM&A of a plough horse as a war horse.”

[Editor’s note: It was at about this point in Floki’s talk that the people in the front row started to grumble.]

“If we’re talking about a piece of warrior-stuff that also happens to be a warrior’s working and living place (I’m thinking of ships, mostly, so my apologies to Thorberg, but also of castles, forts and stockades) then there’s at least one or two more ill at ease to talk about – habitability and sustainability. Keep in mind that all the stuff we provide is just that much more for the enemy to take as a prize if our warrior isn’t in condition to use it. So we have to keep our man at least dry enough, warm enough, and fed enough to be worth a fight. Do I dare to add clean enough? Probably not; few among us have ever cared much about that before. But those are some of the things that habitability might be made up of. As for sustainability, why, I have to admit I’ve never figured out exactly what the Wise-Men mean by that, except maybe whether we can bring our cattle and pigs with us on a campaign, not to speak of our women and children. But if that’s what they mean, they might just say so.

Communication. “We all know about ways to send messages without a messenger. That works in some places. People who have seeing-stones are very fortunate indeed, and I realize that some of you are working on that for all of us, although not much is said about it. But until you work it out, I’m afraid ordinary people will still have to be content with smoke or flags in the day, lights and fires at night, drums in the woods, and horns in the field.

“In the meanwhile, too, we are all of us aware that sending a message over any great distance means sending a messenger, on a horse over roads or across country that isn’t too rough; on foot for closer or rougher ground. Mobility is almost the whole story for a messenger. A man could even leave his shield and armor behind (even his sword if he’ll part with it) just so it makes him get where he’s going sooner. See, if a messenger gets into trouble that he can’t ride or run around, it’ll likely enough be real trouble, and that’s it for him, shield or no, and that’s probably it for the message, too.

“So we take it into our minds to hide it, or cipher it. We don’t write it down or speak it plain if it’s important and could find its way into the enemy’s hands. I do hope, you seeing-stone mongers, that when you get your seeing-stones working properly you will still remember that the enemy may have seeing-stones, too. And you warriors, I hope you will know to keep messages short and secret, just as we do with smoke, lights, or drums. I’m sometimes afraid that new things, being entertaining to use, make us careless.

“It is a very good thing on the field if you can call friends to you at need, in the middle of a fight, or let them know which way to move. The horn makers here are very good at their craft, I doubt not, but the hard part is arranging that horn calls be unambiguous, so our people will know who the call is for, and not too easy for the enemy to figure out. I often wonder if our horn makers can possibly do something about that.

Affordability. “None of us will be comfortable admitting this, but there are other things to delight and entertain us in this world besides fighting. It may be true that we can get many of those other things by fighting and taking them. But at times even we have found that there’s no good way to get them except buying them. Therefore, not having all the gold we’d like, we can’t necessarily spend as much as we’d like on warrior-stuff.

“But beside that, what can be said about deciding how much gold to spend on this kind of war-gear, or that kind of war-gear? Fortunately, speaking as a smith, I am grateful that this is a question that is not asked of us smiths, but generally only of Wise-Men, by the People that Handle the Gold. The Wise-Men, I suppose, then consult with those who know the enemy, and others, make the magic passes that are called for, and eventually return answers to the People that Handle the Gold.

“In turn, the People that Handle the Gold then select from among the Wise-Men’s answers a mix of answers that they feel will be judged most favorably by the King. The King then concurs with the recommendation, or does not. If he does, then the gold flows. If he does not concur, but instead prefers some other answer, never you mind why, then he chooses that, and the gold flows in that direction.

“If, however, the King does not find any of the answers satisfying, then the gold does not flow so much. Probably, some of the People that Handle the Gold have their heads handed to them, and perhaps some of the Wise-Men, too. Usually, though, the People that Handle the Gold, and the Wise-Men, have arranged things so that most of the failure can be blamed on craftsmen, for not being more creative or industrious, so some of them have to suffer as well. In any case the Wise-Men, those that are left with what to be wise with, have to be consulted again.

“Now all this is a mystery, of course, even when the King is the supreme authority over all the People that Handle the Gold. When power over the gold is usurped by a Parliament, as in a constitutional monarchy, or worse, in a republic, it is beyond mystery. More cannot be said here of this matter.

“But even for warriors and craftsmen, questions of the following form can at least be asked, though not so easily answered:

“On the kind of ground where we are planning to fight, can three archers in padded cloth on ponies usually beat one full-armored man on a heavy horse? If not, then, can four? How many times out of hundred? That done, what are the costs in gold of acquiring ponies and archers, plus certain bows and arrows, by comparison with the costs of a heavy horse and accouterments, the lance and the rest, and one man in full armor? And then, the annual costs of keeping the same in readiness, what are they?

“Now, perhaps, you will understand why the Wise-Men and the People that Handle the Gold (not to mention the King) are more to be courted and reverenced than those who are still only warriors, and how much less we craftsmen: swordsmiths, bow-makers, and shield-builders, horn-hollowers and seeing-stone contrivers, difficult though our callings may be, and useful and beautiful the works of our hands.

[Editor’s note: It was at this point that the front row rose in a mass and seized Floki by the scruff, and frog-marched him out of the hall for the beating that he deserved. It can be said that he recovered his senses after some time, but schooled himself to silence at A.S.N.E. meetings thereafter. However, Floki was found to have some additional notes on his person when he was carried from the hall, and in good consideration these are appended hereto.]

Here are the notes that fell out of Floki’s pockets when he was drubbed. No one has yet been able to figure out if they make sense, and Floki himself, who usually has no objection to a good brawl, but does not so much enjoy fighting alone against ten or more, is naturally reticent about offering any explanations.


I do not care much for the word “best” when it comes to warrior-stuff. (The Wise-Men use the word “optimum,” but I expect that’s mostly because they need to speak Latin, having visited Rome.) I have never heard a practical way of posing, still less of solving, the problem of finding the “best” weapon, or the “best” mix of hitting power, mobility, and survivability. I wish I knew how to solve these problems, because if I did I certainly wouldn’t need to make my living down at that hot, dirty, dusty, damned old forge.

How would you address the following, for example?

1. ‘‘Make it most likely that we can convince the population of the neighboring Kingdom (or their King) to behave in a certain way, subject to the gold we have, the men we have, our present understanding of swords, spears, and bows, and our political and moral restraints, such as they are. ‘‘

2. `‘Under the same restraints, make it most likely that we’d prevail in a war against those same people, subjugate their King, take his royal throne, and loot his Kingdom eight ways to Sunday. ‘‘

3. ‘‘I expect that these problems are overly ambitions and underly well-defined, at least for us in the warrior or warrior-stuff businesses. How if we try these instead:’‘

Offense: Maximize the expected attrition to enemy things, for a given cost, by adjusting how much of our gold is put into hitting power, mobility, and survivability. (Let those who know the enemy best, if they will, tell us exactly what the enemy things are.) ‘‘

Defense: Minimize the expected attrition that enemy things can do to our own things, for a given cost, by adjusting how much of our gold is put into hitting power, mobility, and survivability.’‘

Attrition Ratio: Maximize the attrition we perform on the persons and properties of the enemy per unit of attrition he performs on us.’‘

Even posed thus, these problems are obviously unfitted to the likes of me, Floki the One-Eyed, or anyone that I know, including every man in this room, I would say. Whatever choices we make, be assured that our possible enemies are considering the same matters from the opposite side. It is not wise to flatter ourselves that they’re very much less capable than we. ‘‘

I have one other thing to say about gold. Asking how much a thing is going to cost before you’ve tried to make the first one is a fine recipe for getting a wrong answer. The People that Handle the Gold like to use the words “total ownership cost.” To say that they have guessed how much a thing will take of the King’s treasure over its entire “life cycle.” This is an amusing thing to me, because the length of life is in considerable doubt, as we’re about to send that thing, whatever it is, into battle. But never mind that.’‘

The process of dividing up the gold, as I’ve said before, is at the King’s pleasure, or, in places too barbarous to support a decent absolute monarchy, at the vote of a Parliament or Congress. These may be made up of men who have inherited their places in spite of their evident unfitness, or who are elected by the ignorant general public for a term of years, definite or indefinite. The point is that for such men and such governments, saving money in the future in exchange for spending more now is not only risky, but possibly unconstitutional as well. I sometimes think that it’s best to forget about the illusion of total ownership and think hardest about acquisition cost instead. That is more than hard enough. But we do what we’re told and we take what we get.’‘

As for the costs of keeping a thing, there is this: as warrior-stuff becomes more complicated we do need to pay heed to the influence of other things than fighting. Transport, replenishment, maintenance, and training come to my mind. These may seem to be ancillary to the business of fighting and in most respects they are, just as RM&A and the other ill at ease are handmaidens of hitting power, mobility, and survivability. Nevertheless, they may be mentioned in the requirements that the King and high-ranking warriors lay upon us, and they can’t be neglected at our great peril, and have mercy on our souls. ‘‘

But if there is peace for any amount of time, then we may find that we replenish, maintain, and train even more than we fight, much more. Disappointing as that may be, there is even worse of it: we may begin to forget the purposes we built stuff for in the first place: to fight, which is to say, to hit. That is how we fall into the trap of wanting to turn war into just another business in the first place. ‘‘


Why is it so hard to keep our new warrior-stuff on schedule and under budget? I have tried to list what we do when we develop a new thing, and the best I have done I will tell you now. It is tempting to think that my list is something we follow one step at a time, but I confess that I’ve never seen it done that way. Instead, the list is like ingredients swirling around each other and mixing up like soup. I am sure that my list is incomplete, too, but I make no apologies for it.’‘

More important, this list makes it sound like one person may be exercising authority over all the ingredients, like a cook in a kitchen. That, too, is wrong. Not even the King exercises that authority; if he does, he is likely enough to get it wrong, too. But, at the risk of seeming to advise the King on what he should and should not do, Kings are busy with high matters and that’s as it should be. Let the cooks do the cooking, is what I say. ‘‘

Nor, in general, has the King delegated sufficient authority to one man. Warriors, bureaucrats, spies, propagandists, consulting Wise-Men, artists and craftsmen, politicians, and the People that Handle the Gold, all are in this struggle to either gain control, to claim the credit if things are going well, or to avoid the blame if things are going ill. Who is in control? I have begun to think that no one is, not even in an autocracy. It is pulled back and forth perpetually. I have said it before, and I’ll say it again: as it is in a battle, so it is in the things we make for battle. ‘‘

But leave it. Here is my list of some of the things we do. Each of them is a heavy burden, from what I know and from what I’m told. You can believe that.’‘

Intelligence. Those who know the enemy go out and study him, his existing and projected warrior-stuff, and his doctrines. The methods these people use make them very secretive, and that, together with studying the arts of the enemy too closely, makes them subtle and quick to anger. Used to being deceived, they practice deception to a very fine degree. In the end some of them, out of pride or fear, come to practice self-deception as well. Nevertheless, many of them are Wise-Men, too, which does not make them any easier to comprehend. It would be wonderful if the Wise-Men could let us know the enemy’s intentions as well as his capabilities, but this is often a forlorn hope. Capabilities usually take time to come about, but intentions can change overnight, in an hour, in the blink of an eye. Plans are quite likely to change abruptly as soon as it is known, or even suspected, that they have been discovered, anyway, so the very act of discernment may be at least partly self-defeating.’‘

Capabilities. Warrior-craftsmen, with a leavening of Wise-Men, propose a set of alternative abilities that might be possible, and might also help achieve a military objective as a nation, as they perceive it. These capabilities can then be linked with a new piece of warrior-stuff. The seeing-stones come to mind, as they started out this way. Bias can become very pronounced in this. Often the bias can be associated with one or more of the following seven sins: ‘‘

Proprietorship. “I know it’s a good idea – it’s my idea.”‘‘

Seduction. “Look! I will show you a rare and wonderful thing!”‘‘

Novelty for its Own Sake. “We’ve never done any better than blunder about like a bull in a thicket: so anything new must be good.”‘‘

Nostalgia. “I miss the way it was when I was young and carefree.” ‘‘

Inertia. “I don’t care. I don’t have to.” ‘‘

Not-Invented-Here (NIH). “This is Bjorn’s idea and everyone knows it – it won’t do me any good to see it pursued.”‘‘

Vested Interest. “That thing will pull gold away from my thing; if it succeeds, it may delay or even supersede my thing. I can’t have that.”‘‘

There are undoubtedly other sins that I haven’t thought of, but seven should be enough to get started with. ‘‘

Metrics. Warriors, the People that Handle the Gold, and Wise-Men, as required, establish the measures of “effectiveness,” of cost, and of risk, so that different items of warrior-stuff can be compared and judged preferable or not. Risk and cost, however difficult they may be to quantify, can at least be explained. “Effectiveness” for a warrior-thing is usually so complicated, for reasons I’ve tried to lay out as clearly as I can, that it’s often impossible to even say what it is. It is near to meaningless unless we’ve said what the enemy can bring against it, too, and how we both mean to fight. ‘‘

We may presume that “effectiveness” is a very complicated result of hitting power (of various kinds at various ranges), mobility (over various distances and kinds of ground), and survivability (against various weapons). So the hitting power, mobility, and survivability we need to know are not simply ours, but also those of them, our enemy, along with our appreciation of the numbers and of the ground. It is very difficult to measure fighting effectiveness, even in principle, except by observing the results of fighting or at least mock-fighting, but then it would have to be very realistic mock-fighting indeed. I myself would not want to stand too close to such a mock fight, especially if it involved archery. ‘‘

Beware of anything calling itself a “measure of effectiveness” that purports to be derived from the mere performance of our own thing, without reference to the enemy, the numbers, or the ground. It is likely to be little but the residue of bias. In particular, treat with scorn any measure of effectiveness if it is only a weighted sum of aspects of performance. That cannot be effectiveness, nor can it be a sound basis for preference, even in principle, except under two special conditions. One condition is that nobody gives a rat’s hindquarters what we choose, so any order of preference will do. The Wise-Men refer to that as a “trivial case.” The other condition is that the King has decreed it so and we have all agreed that whatever the King says goes. Looking into the seeds of time to see which ones will grow and which will not, I say that somebody will prove this, some day. Like as not, Floki being a swordsmith, the man who does prove it will bear the name of a projectile weapon. ‘‘

Scenarios. Based on history and imagination, warriors and Wise-Men try to think what future engagements, campaigns, and wars will be like. They construct more or less elaborate stories, called scenarios, that form frameworks for war plans and war games. Once again, beware. Bias may easily play a part in constructing scenarios.’‘

Concepts. Wise-Men and warriors, assisted by inventors and craftsmen, generate new ideas for warrior-stuff. They develop them to the extent of saying whether or not they are physically impossible, and perhaps saying what advantages in hitting power, mobility, survivability, RM&A, safety, or affordability might result if we had such stuff. Of course, what is thought to be impossible in one age may well change in the next and become quite possible, inevitable in fact. I’m sure that when craftsmen were making swords out of bronze, they thought that making swords out of iron was impossible. Well, it’s not. ‘‘

But be wary: estimates of the attributes of things that exist only as concepts are much at the mercy of advocates and adversaries. That is the battle before the battle, the battle of bias, if I may call it so. And who is a man to believe? Why, obviously, Him to Whom the Oath is Sworn. ‘‘

Experiences. Warriors participate in a few real wars, hopefully not too big. More safely, they can also play war games. These include variations of our own and the enemy’s warrior-stuff and doctrines. The lesson is this: beware of believing your own bragging, especially if you’ve won a few. In games, be sure to play the enemy now and then. I suppose an argument can be made, strictly in terms of finding out what works and what doesn’t, that even in a real war it might be instructive to switch sides from time to time. But don’t. ‘‘

Transition. Warriors, Wise-Men, and People that Handle the Gold compare and select the preferred kinds of warrior-stuff to develop from concepts into real war-stuff, to be built and bought. This is an intensely mysterious part of the “process,” if it is in truth a process. Do not be shocked, you craftsmen, if the worse sometimes appears the better cause. ‘‘

Requirements. Warriors and Wise-Men define and issue specific requirements and constraints for war-stuff designers and makers to meet. This is often the most difficult and dangerous ingredient in the soup, where the entire mix can start to go sour very quickly. Requirements writers (especially those who think they understand what the warriors are saying, but don’t) can easily make requirements too hard or too easy. Either way can spoil the result. ‘‘

Cost and Schedule Estimates. This is usually an uncomfortable conversation between factions of Wise-Men, craftsmen, and People that Handle the Gold, like a hundred surgeons all looking for the same lump. Nobody believes any of it, but we have to line up on one side or the other, as suits our own interests, provided they are in no wise contrary to those of Him to Whom the Oath is Sworn. ‘‘

Risk Assessment and Mitigation. This is where we all ask ourselves how sure we are of our ground in guessing how our stuff will perform, or our cost estimate, or our schedule. We confess, if we are even middling honest, the extent of our uncertainty, that is, the likelihood and consequences of being wrong about things we’ve had to guess. We prepare plans to reduce risk. That is, we lay our plans for knowing things with more certainty, and reducing the likelihood and lessening the consequences of being caught out. ‘‘

Design, Build, Test. At this point we craftsmen have it. We are assisted by such Wise-Men as we think might be needed (the more of them, unfortunately, as a thing is newer and more untried), and we are watched over by the People that Handle the Gold. We may also be watched over by the King himself, if he is interested. This makes everything a little more of a nerve-strumming. ‘‘

We design, and build a first article, maybe, or a small batch, for test use by real warriors. My swords, for example, go out and get used. And woe to me if they fail on my account. But only so can I refine the estimates of performance, cost, schedule, and thereby validate (perhaps) the estimates of my sword’s “effectiveness,” as it was assumed in games, for example. If I am very lucky, I may see the tests extended into actual war-fighting. That may help me, but I am wary still. People can learn the wrong lessons even from real fights. Winners can be especially likely to fall into that trap, because wishful thinking will turn every conceivable fight into the fight they have just won, at least in their own minds. The enemy, of course, having just lost, will have other ideas, if he still has his head on.’‘

There are many ways to do “design, build, test,” in little bites or big bites. Little bites are safer, in general, but when added up they often appear to add up to more cost. Usually this is an illusion, as it turns out. On their better days the People that Handle the Gold may be willing to spend some money to reduce the risks, and so the bites can be bigger. Be grateful for this when it happens, for it isn’t often. Have I not tried it myself with swords with curved blades instead of straight, and have I not found that they could be made lighter and still not break? They work quite well, but I still have no local market for them. Warriors are often conservative. It is their life wagered on the outcome, now, not mine. Those that like their heavy swords are awfully hard to convince. Were I to cut someone down myself, still would they take more convincing, and besides I’d probably lose as many orders as I gained.’‘

Contracting. There is a certain class of Wise-Man that cannot be condemned harshly enough to receive what they deserve. These are a sub-species of lawyer, men who deal only with agreements between craftsmen, requirements writers, and the People that Handle the Gold. The truth is not in them. Their craft is in making sure that every quibble that could be raised is answered before the need arises, and their delight is in laying snares for honest men. Their words are twisted, their oaths faithless, and their names on a waste of pulp. They are capable only of obstruction and, if it were up to me, that is what I would use them for; I would build every one of them into the fill of a foundation wall. Rot, is what I say.’‘

Production and Service. Now, if we’ve somehow gotten around the lawyers, at last we manufacture and field and support our products. At the same time, though, the Wise-Men, the People that Handle the Gold, and their Masters, take notice of the world as it is, to see if what we have made still makes sense. If it does, we may continue in production and service for some time. If our stuff gets used, then after every fight we owe it to ourselves to look and see whether it’s still doing as well as we’d hoped. But often things are confused, and even the warriors who were there may have difficulty knowing what really happened. It is as easy for them to get it wrong as for anyone else. And in many cases they will not want to speak of it overloud, because the tale may come to the ear of the enemy. Or it may be that they themselves did something not quite right, and find it an embarrassment, in case it comes to the ear of the King.’‘


And, all the while we are stirring this soup our enemies are trying to find ways in which they can make sure that our ingredients are wrong from the beginning. If we start with a recipe that makes sense to begin with, they will try to find a way of undoing and spoiling it as soon as they can. It is their duty to the One to Whom Their Oath is Sworn. ‘‘

Is it any wonder, my friends, given a problem difficult or impossible of solution, no “process” to speak of (though we do speak of it, endlessly, until we grow tired of wagging our tongues), all of us in a battle against ourselves for our King’s favor and for the favor of the People that Handle the Gold, before we ever come to a real battle, then to face an opponent about as able as ourselves, and maybe all the meaner for it if we’ve been successful in the past, planning and building to requirements that come and go like phantoms in the dark, is it any wonder, I say, that warrior-things are not as things of the commercial world? Is it any wonder that warrior-stuff is high-priced and high-strung? Not at all. ‘‘

But thus do we, along with our enemies, may God help us, chase each other’s tails, and make sure that we must cook this same soup over and over again, until the One to Whom the Oath is Sworn release us from it, or death take us, or the world end.’‘


If it be true, as I have argued, that war is not going to be turned into a business, then how can we make our stuff work better? I do not mean to tell each of you how to do your own particular job; we have different jobs and we must all learn for ourselves. But how can we move forward, and at the same time remain grounded in the things we have learned from experience, the bitter along with the sweet? This is what I think, and if I haven’t offended you already, you are probably fast asleep, so I’m quite safe: ‘‘

1. Craftsmen and Wise-Men, study continually what warriors actually do. Even if we once were warriors ourselves, we must always try to remember that the world changes in spite of us. It’s true that we study the old ways; in fact we cannot avoid it. But we must study what is happening now, also. We must all be open to correction; hard though it be we must set time aside to listen to new ideas. We must all try to remember that none of us knows everything. ‘‘

2. Warriors, retain your prerogative and your responsibility to tell craftsmen what problems you face in battle, and so to tell your craftsmen as forthrightly as you can what you think you need to do in battle. You should not tell craftsmen how to be craftsmen, any more than you would like craftsmen to tell you how to be warriors. ‘‘

3. Put aside the illusion that making up a new word is the same as making a new thing happen. Perhaps the Wise-Men will be able to make this illusion come true someday, but that day is not yet come. For myself, I fear that day, for one errant word or thought could then be the ruin of all. The deeper and newer a word sounds on first saying it, or hearing it, and the more good things are promised of it, the more suspicious we must be, not of the word, but of ourselves. Some there are who believe that if we wish for something, no matter what it may be, we have only to organize our effort properly and it will happen. Foolishness. Foolishness.’‘

4. Warriors and craftsmen of different disciplines and traditions, stop fighting against each other for the King’s favor, or the favor of the People that Handle the Gold. It is ruinous. In war all must fight for the common good, not that of their own way alone. If you must strive with one another, compete fairly on the grounds of your results.’‘

5. All of us, we must all realize that the enemy is at work. We must not believe our own boasts. We must not become over-specialized or dependent on one way of war. The enemy is watching for that, and it makes us easier to beat. Wise-Men, and such of you craftsmen who have studied, come forward with your best ideas. Those who are willing to forego somewhat of personal gain, and work together for the common good even if it be to their own cost, their virtue should not go unrewarded; let the People that Handle the Gold look to it.’’

Course Objectives

Having successfully completed this course, the student will be able to:

  • Describe and demonstrate a total-ship systems approach and understanding of naval ships, naval ship missions, combat systems, human systems and automation, ship system survivability, mission effectiveness, and technology development risk.
  • Develop and utilize metrics for assessing naval ship mission effectiveness and technology development risk.
  • Integrate and synthesize a naval ship with combat, power and human systems.
  • Develop naval ship general and system arrangements including machinery, combat systems, distributed systems and topsides considering total system integration, functionality, performance and survivability.
  • Use deactivation diagrams for assessing ship vulnerability and RM&A.
  • Conduct simple ship vulnerability (radar cross section) and survivability analyses.
  • Assess the impact of modularity on ship cost, effectiveness and risk.

{* Conduct simple shock and DDAM analyses.}

{* Perform RM&A}

Naval Missions and Support Activities

What is the difference between a naval vessel and a commercial vessel? According to the CNO's Sailing Directions [[1]] there are three:

Naval vessels must:

  • Operate Forward
  • Be Ready
  • Fight

These three 'roles' all have impact upon the ship design. We will not, unfortunately, have time to delve into each of them in the course. Let's focus instead upon the "Fight" finction.

  • Missions / Warfighting Areas / Required Operational Capabilities (ROCs) of each
  • Ship Types
    • Surface Combatants
    • Aircraft Carriers
    • Amphibious Warfare Ships
    • Combat Logistics Force Ships
    • Mine Warfare Ships
    • High Speed Ships and Craft, Multi-hulls
    • Naval Submarines

The obvious difference between a naval and a civil vessel lies in the naval missions, and arguably also in the range of missions or even the range of requirements contained within a single mission.

This chapter provides an overview of naval missions and support activities, and examines the interaction between missions, activities and specific systems and tasks. The definitions of "mission", "support activity" and "task" are not particularly rigid, but can be demonstrated by example. Consider replenishment at sea (RAS), described later in more detail. The RAS support activity describes a collection of different types of resupply activities which includes ship-to-ship connected replenishment and vertical replenishment using aircraft. The tasks associated with each activity provide a lower-level, functional definition of the steps required to accomplish the activity. This chapter does not provide detailed task analyses, but does attempt to define an appropriate framework for this process.

The naval missions described here are taken largely from NATO Standardization Agreement (STANAG) 4154. These definitions are adapted from past studies: Hills (1991), Smith and Thomas (1989). Walden and Kopp (1985), and Lain et al (1979). STANAG 4154 introduces a new concept called "support activities" to cover cross-mission functions, and the mission speed profile (MSP) is described. The missions and support activities are well suited to describe both peace and wartime scenarios, although the MSP, acceptable performance criteria, and/or relative importance of the various systems and tasks may vary, as discussed later.

The present author has not studied whether this is a sufficient set of mission descriptions to include OOTW and GWOT. This mission set is, however, sufficient to introduce the student to the concept of the naval missions and the influence that these missions have upon design.

Table 3.1 summarizes the naval missions and support activities considered. Note that this list of missions and activities does not cover all possibilities, and so it should be considered as a template for general guidance.

Type Name Description
Naval Mission
TAP Transit and Patrol
ASW Anti-Submarine Warfare
AAW Anti-Air Warfare
SUW Surface Warfare
MCM Mine Countermeasures
NSW Naval Special Warfare
INT Naval Intelligence Gathering
OOTW Operations Other Than War
Support Activities
NAO Naval Air Operations
RAS Replenishment at Sea
WRL Weapon Systems Reload
MAR Maintenance and Repair
Table 3.1: Summary of Naval Missions and Support Activities

The mission names and acronyms defined in Table 3.1 will be used throughout the text.

In addition to providing a top-level description of the ship's general activities, each mission is also generally associated with a mission speed profile (MSP.) The MSP defines the ship's operating tactics, in terms of the relative amount of time spent at various ship speeds. Figure 3.1 illustrates an example transit and patrol MSP for a frigate or destroyer. However, Since the MSP is affected by both the particular nation's operating doctrine and by the specific ship type and systems being used, it is difficult to define appropriate MSPs before a number of details have been considered. For example. a representative MSP for ASW can vary from a single fairly constant speed for "traditional" convoy escort, to a combination of very low and very high speeds for "sprint and drift" operations, where the ship stops and drifts to listen and then sprints at high speed to the next drift position.

Figure 3.1: Example Transit and Patrol Mission Speed Profile [missing]

Naval Missions

The naval missions are the top-level descriptions of the major aspects of naval warfare. The activities, systems and tasks used for these missions must be defined before the designer can select or define criteria for assessing the effects of ship motions and related phenomena on the combat capability of the ship. As noted earlier the level of detail can vary from a broad, overview using generic systems and tasks, to a very detailed description of real systems with a step-by-step task analysis. By considering variations in sea state, geographic location, tactics (e.g. MSP and constraints on ship course), and ship loading condition, the designer can model the wide range of conditions expected to be encountered for the ship or ships being considered. The combat missions are discussed in more detail in the following sections, as the systems and tasks are described.

Transit and Patrol

This mission represents the ship's ability to transit as required across the seas, and to be aware of the presence of other ships, submarines, and aircraft in the patrol area. Thus, TAP models the situation where the ship is moving from one place to another, performing routine shipboard activities, and using a variety of sensors to examine the surrounding environment. The TAP mission is an appropriate place to consider a variety of generalship platform, maintenance activities, and personnel habitability issues, as discussed later in Chapter 6. Also, the TAP mission covers special activities such as Search and Rescue (SAR), offshore patrol for civilian agency support (e.g. fisheries patrol and smuggling interdiction), and military surveillance patrols.

The TAP mission can model particular situations by developing suitable mission speed profiles and selecting appropriate systems. For example, a covert mission to locate and detect subsurface targets could be modeled by selecting a low ship speed, and using only passive sensors (e.g. towed array sonar, and infra red (IR), laser and visual sensors). Similarly, a pursuit scenario where the ship is chasing a fleeing target can be modeled by a sustained high ship speed, or the seakeeping assessment process can be used to determine the maximum sustained speed for a range of sea conditions. Other types of shipboard activities can be considered in TAP by defining appropriate criteria, such as:

  • damage control, firefighting and emergency structural repairs; and,
  • small boat operations (launching and recovery).

Survivability in extreme seas is a special subset of the TAP mission. Two aspects of survivability are of major importance; ultimate stability; and ultimate strength. Failure to satisfy both of these conditions usually results in loss of the ship, either due to capsize or breaking up. There are intermediate levels of problems as well, especially for ship strength, where local damage can be caused by a variety of effects (e.g. hull slamming, green seas loading, whipping. fatigue. etc.). Damage to mission-critical systems can leave the ship vulnerable, ineffective or a liability to missions involving multiple ships.

ASW - Anti-Submarine Warfare


Anti-submarine warfare (ASW) is a branch of naval warfare that uses surface warships, aircraft, or other submarines to find, track and deter, damage or destroy enemy submarines.

Like many forms of warfare, successful anti-submarine warfare depends on a mix of sensor and weapon technology, training, experience and luck. Sophisticated sonar equipment for first detecting, then classifying, locating and tracking the target submarine is a key element of ASW. To destroy submarines both the torpedo and mine are used, launched from air, surface and underwater platforms. Other means of destruction have been used in the past but are now obsolete. ASW also involves protecting friendly ships.

In the immediate postwar period, faced with the prospect of large numbers of Soviet submarines as capable as the Type XVIIs and XXIs, or better, new ASW weapons were essential. This led to the introduction of longer-ranged ATWs, such as Ikara, Weapon Alpha and ASROC. Nuclear submarines, even faster still, posed an even greater threat; in particular, shipborne helicopters (recalling the blimps of World War I)<ref>Price, Alfred. Aircraft versus the Submarine. (London: William Kimber, 1973).</ref> have emerged as essential anti-submarine platforms. A number of torpedo carrying missiles were developed, combining ahead-throwing capability (or longer-range delivery) with torpedo homing.

Since the introduction of submarines capable of carrying ballistic missiles, great efforts have been made to counter the threat they pose; here, maritime patrol aircraft (as in World War II) and helicopters have had a large role. The use of nuclear propulsion and streamlined hulls has resulted in submarines with high speed capability and increased maneuverability, as well as low "indiscretion rates" when a submarine is exposed on the surface. This has required changes both to the sensors and weapons used for ASW. Because nuclear submarines were noisy, there was an emphasis on passive sonar detection. The torpedo became the main weapon (though nuclear depth charges were developed). The mine continued to be an important ASW weapon.

In some areas of the ocean, where land forms natural barriers, long strings of sonobuoys, deployed from surface ships or dropped from aircraft, can monitor maritime passages for extended periods. Bottom mounted hydrophones can also be used, with land based processing. A system like this SOSUS was deployed by the USA in the GIUK gap and other strategically important places.

Airborne ASW forces developed better bombs and depth charges, while for ships and submarines a range of towed sonar devices were developed to overcome the problem of ship-mounting. Helicopters can fly courses offset from the ships and transmit sonar information to their combat information centres. They can also drop sonobuoys and launch homing torpedoes to positions many miles away from the ships actually monitoring the enemy submarine. Submerged submarines are generally blind to the actions of a patrolling aircraft until it uses active sonar or fires a weapon, and the aircraft's speed allows it to maintain a fast search pattern around the suspected contact.

Increasingly anti-submarine submarines, called attack submarines or hunter-killers, became capable of destroying, particularly, ballistic missile submarines. Initially these were very quiet diesel-electric propelled vessels but they are more likely to be nuclear-powered these days. The development of these was strongly influenced by the duel between Venturer and U-864.Template:Citation needed

A significant detection aid that has continued in service is the Magnetic Anomaly Detector (MAD), a passive device. First used in World War II, MAD uses the Earth's magnetosphere as a standard, detecting anomalies caused by large metallic vessels, such as submarines. Modern MAD arrays are usually contained in a long tail boom (fixed-wing aircraft) or an aerodynamic housing carried on a deployable tow line (helicopters). Keeping the sensor away from the plane's engines and avionics helps eliminate interference from the carrying platform.

At one time, reliance was placed on electronic warfare detection devices exploiting the submarine's need to perform radar sweeps and transmit responses to radio messages from home port. As frequency surveillance and direction finding became more sophisticated, these devices enjoyed some success. However, submariners soon learned not to rely on such transmitters in dangerous waters. Home bases can then use extremely low frequency radio signals, able to penetrate the ocean's surface, to reach submarines wherever they might be.

The military submarine is still a threat, so ASW remains a key to obtaining sea control. Neutralizing the SSBN has been a key driver and this still remains. However, non-nuclear powered submarines have become increasingly important. Though the diesel-electric submarine continues to dominate in numbers, several alternative technologies now exist to enhance the endurance of small submarines. Previously the emphasis had been largely on deep water operation but this has now switched to littoral operation where ASW is generally more difficult.

There are a large number of technologies used in modern anti-submarine warfare:

An MH-60R conducts an airborne low frequency sonar (ALFS) operation during testing and evaluation.

In modern times forward looking infrared (FLIR) detectors have been used to track the large plumes of heat that fast nuclear-powered submarines leave while rising to the surface. FLIR devices are also used to see periscopes or snorkels at night whenever a submariner might be incautious enough to probe the surface.

The active sonar used in such operations is often of "mid-frequency", approximately 3.5 kHz. Because of the quietening of submarines, resulting in shorter passive detection ranges, there has been interest in low frequency active for ocean surveillance. However, there have been protests about the use of medium and low frequency high-powered active sonar because of its effects on whales. Others argue the high power level of some LFA (Low Frequency Active) sonars is actually detrimental to sonar performance in that such sonars are reverberation limited.


Satellites have been used to image the sea surface using optical and radar techniques, and it is claimedTemplate:By whom these might be used for indirect detection of submarines, as could thermal imaging.Template:Citation needed Fixed-wing aircraft, such as the P-3 Orion provide both a sensor and weapons platform as do some helicopters like the SH-60 Seahawk, with sonobuoys and/or dipping sonars as well as aerial torpedoes. In other cases the helicopter has been used solely for sensing and rocket delivered torpedoes used as the weapon. Surface ships continue to be a main ASW platform because of their endurance, now having towed array sonars. Submarines are the main ASW platform because of their ability to change depth and their quietness, which aids detection. In the future unmanned vehicles may be used in the ASW role. In early 2010 DARPA began funding the ACTUV programme to develop a semi-autonomous ocean going unmanned naval vessel.

Today some nations have seabed listening devices capable of tracking submarines. It is known to be possible to detect man-made marine noises across the southern Indian Ocean from South Africa to New Zealand.Template:Citation needed Some of the SOSUS arrays have been turned over to civilian use and are now used for marine research.<ref>National Oceanic & Atmospheric Administration VENTS project Website</ref>

AAW - Anti-Air Warfare


NATO defines air defense as "all measures designed to nullify or reduce the effectiveness of hostile air action."<ref name="AAP-6">AAP-6</ref> They include ground and air based weapon systems, associated sensor systems, command and control arrangements and passive measures. It may be used to protect naval, ground and air forces wherever they are. However, for most countries the main effort has tended to be 'homeland defense'. NATO refers to airborne air defense as counter-air and naval air defense as anti-aircraft warfare. Missile defense is an extension of air defense as are initiatives to adapt air defense to the task of intercepting potentially any projectile in flight.

In some countries, such as Britain and Germany during World War II, the Soviet Union and NATO's European Command, ground based air defense and air defense aircraft have been under integrated command and control. However, while overall air defense may be for homeland defense including military facilities, forces in the field, wherever they are, invariably deploy their own air defense capability if there is an air threat. A surface based air defense capability can also be deployed offensively to deny the use of airspace to an opponent.

General description

[[File:Akash SAM.jpg|thumb|India's Akash GBAD surface-to-air missile]]

The essence of air defense is to detect hostile aircraft and destroy them. The critical issue is to hit a target moving in three-dimensional space; an attack must not only match these three coordinates, but must do so at the time the target is at that position. This means that projectiles either have to be guided to hit the target, or aimed at the predicted position of the target at the time the projectile reaches it, taking into account speed and direction of both the target and the projectile.

Throughout the 20th century air defense was one of the fastest-evolving areas of military technology, responding to the evolution of aircraft and exploiting various enabling technologies, particularly radar, guided missiles and computing (initially electromechanical analog computing from the 1930s on, as with equipment described below). Air defense evolution covered the areas of sensors and technical fire control, weapons, and command and control. At the start of the 20th century these were either very primitive or non-existent.

Initially sensors were optical and acoustic devices developed in World War I and continued into the 1930s,<ref>"Huge Ear Locates Planes and Tells Their Speed" Popular Mechanics, December 1930 article on French aircraft sound detector with photo</ref> but were quickly superseded by radar, which in turn was supplemented by optronics in the 1980s.

Command and control remained primitive until the late 1930s, when Britain created an integrated system<ref>Checkland and Holwell pg. 127</ref> for ADGB that linked the ground-based air defense of the army's AA Command, although field-deployed air defense relied on less sophisticated arrangements. NATO later called these arrangements an "air defense ground environment", defined as "the network of ground radar sites and command and control centres within a specific theatre of operations which are used for the tactical control of air defense operations".<ref name="AAP-6"/>

Rules of Engagement are critical to prevent air defenses engaging friendly or neutral aircraft. Their use is assisted but not governed by IFF (identification friend or foe) electronic devices originally introduced in World War II. While these rules originate at the highest authority, different rules can apply to different types of air defense covering the same area at the same time. AAAD usually operates under the tightest rules.

NATO calls these rules Weapon Control Orders (WCO), they are:

  • weapons free: a weapon control order imposing a status whereby weapons systems may be fired at any target not positively recognized as friendly.
  • weapons hold: a weapon control order imposing a status whereby weapons systems may only be fired in self-defense or in response to a formal order.
  • weapons tight: a weapon control order imposing a status whereby weapons systems may be fired only at targets recognized as hostile.<ref name="AAP-6"/>

Until the 1950s guns firing ballistic munitions were the standard weapon; guided missiles then became dominant, except at the very shortest ranges. However, the type of shell or warhead and its fuzing and, with missiles the guidance arrangement, were and are varied. Targets are not always easy to destroy totally, although damaged aircraft may be forced to abort their mission and, even if they manage to return and land in friendly territory, may be out of action for days or permanently. Ignoring small arms and smaller machine-guns, ground-based air defense guns have varied in calibre from 20 mm to at least 149 mm.<ref>Routledge pg. 456</ref>

Ground-based air defense is deployed in several ways:

  • Self-defense by ground forces using their organic weapons, AAAD.
  • Accompanying defense, specialist aid defense elements accompanying armoured or infantry units.
  • Point defense around a key target, such as a bridge, critical government building or ship.
  • Area air defense, typically 'belts' of air defense to provide a barrier, but sometimes an umbrella covering an area. Areas can vary widely in size, belts along a nation's border, e.g. the Cold War MIM-23 Hawk and Nike belts that ran north–south across Germany, a military formation's manoeuvre area, or the area of a city or port. In ground operations air defense areas may be used offensively by rapid redeployment across current aircraft transit routes.

Post-war analysis demonstrated that even with newest anti-aircraft systems employed by both sides, the vast majority of bombers reached their targets successfully, on the order of 90%. This was bad enough during the war, but the introduction of the nuclear bomb upset things considerably. Now even a single bomber reaching the target would be unacceptable.

The developments during World War II continued for a short time into the post-war period as well. In particular the US Army set up a huge air defense network around its larger cities based on radar-guided 90 mm and 120 mm guns. But, given the general lack of success of guns against even propeller bombers, it was clear that any defense was going to have to rely almost entirely on interceptor aircraft. Despite this, US efforts continued into the 1950s with the 75 mm Skysweeper system, an almost fully automated system including the radar, computers, power, and auto-loading gun on a single powered platform. The Skysweeper replaced all smaller guns then in use in the Army, notably the 40 mm Bofors.

Things changed with the introduction of the guided missile. Although Germany had been desperate to introduce them during the war, none of them became operational during the war. With a few years of development, however, these systems started to mature into practical weapons. The US started an upgrade of their defenses using the Nike Ajax missile, and soon the larger anti-aircraft guns disappeared. The same thing occurred in the USSR after the introduction of their SA-2 Guideline systems.

As this process continued, the missile found itself being used for more and more of the roles formerly filled by guns. First to go were the large weapons, replaced by equally large missile systems of much higher performance. Smaller missiles soon followed, eventually becoming small enough to be mounted on armored cars and tank chassis. These started replacing, or at least supplanting, similar gun-based SPAAG systems in the 1960s, and by the 1990s had replaced almost all such systems in modern armies. Man-portable missiles, MANPADs as they are known today, were introduced in the 1960s and have supplanted or even replaced even the smallest guns in most advanced armies.

In the 1982 Falklands War, the Argentine armed forces deployed the newest west European weapons including the Oerlikon GDF-002 35 mm twin cannon and SAM Roland, while the British forces used the brand-new FIM-92 Stinger. Both sides also used the Blowpipe missile.

During the 2008 South Ossetia war air power faced off against powerful SAM systems, like the 1980s Buk-M1.

AA warfare systems

Although the firearms used by the infantry can be used to engage air targets, on occasion with notable success, their effectiveness is generally limited to long-term attrition rather than preventing individual aircraft from completing weapon delivery. Speed and altitude of modern jet aircraft limit target opportunities, and critical systems may be armored in aircraft designed for the ground attack role. Adaptations of the standard autocannon, originally intended for air-to-ground use, and heavier artillery systems were commonly used for most anti-aircraft gunnery, starting with standard pieces on new mountings, and evolving to specially designed guns with much higher performance prior to World War II. The ammunition and shells fired by these weapons are usually fitted with different types of fuses (barometric, time-delay, or proximity) to explode close to the airborne target, releasing a shower of fast metal fragments. For shorter-range work, a lighter weapon with a higher rate of fire is required, to increase a hit probability on a fast airborne target. Weapons between 20 mm and 40 mm caliber have been widely used in this role. Smaller weapons, typically .50 caliber or even 8 mm rifle caliber guns have been used in the smallest mounts.

thumb|left|200px|A Soviet WW II-era armoured train with antiaircraft gunners Unlike the heavier guns, these smaller weapons are in widespread use due to their low cost and ability to quickly follow the target. Classic examples of autocannons and large caliber guns are the 40 mm autocannon and the 8.8 cm FlaK 18, 36 gun, both designed by Bofors of Sweden. Artillery weapons of this sort have for the most part been superseded by the effective surface-to-air missile systems that were introduced in the 1950s, although they were still retained by many nations. The development of surface-to-air missiles began in Nazi Germany during the late World War II with missiles such as the Wasserfall, though no working system was deployed before the war's end, and represented new attempts to increase effectiveness of the anti-aircraft systems faced with growing threat from bombers. Land-based SAMs can be deployed from fixed installations or mobile launchers, either wheeled or tracked. The tracked vehicles are usually armoured vehicles specifically designed to carry SAMs.

Larger SAMs may be deployed in fixed launchers, but can be towed/re-deployed at will. The SAMs launched by individuals are known in the United States as the Man-Portable Air Defence Systems (MANPADS). MANPADS of the former Soviet Union have been exported around the World, and can be found in use by many armed forces. Targets for non-ManPAD SAMs will usually be acquired by air-search radar, then tracked before/while a SAM is "locked-on" and then fired. Potential targets, if they are military aircraft, will be identified as friend or foe before being engaged. The developments in the latest and relatively cheap short-range missiles have begun to replace autocannons in this role.

Image:Anti aircraft Leningrad 1941.JPG
Fire of anti-aircraft guns deployed in the neighborhood of St. Isaac's cathedral during the defense of Leningrad (former Petrograd, now called St. Petersburg, ) in 1941.

The interceptor aircraft (or simply interceptor) is a type of fighter aircraft designed specifically to intercept and destroy enemy aircraft, particularly bombers, usually relying on high speed and altitude capabilities. A number of jet interceptors such as the F-102 Delta Dagger, the F-106 Delta Dart, and the MiG-25 were built in the period starting after the end of World War II and ending in the late 1960s, when they became less important due to the shifting of the strategic bombing role to ICBMs. Invariably the type is differentiated from other fighter aircraft designs by higher speeds and shorter operating ranges, as well as much reduced ordnance payloads.

The radar systems use electromagnetic waves to identify the range, altitude, direction, or speed of aircraft and weather formations to provide tactical and operational warning and direction, primarily during defensive operations. In their functional roles they provide target search, threat, guidance, reconnaissance, navigation, instrumentation, and weather reporting support to combat operations.

Future developments
Royal Navy Type 45 destroyer is a highly advanced anti-air ship

If current trends continue, missiles will replace gun systems completely in "first line" service. Guns are being increasingly pushed into specialist roles, such as the Dutch Goalkeeper CIWS, which uses the GAU-8/A Avenger 30 mm seven-barrel Gatling Gun for last ditch anti-missile and anti-aircraft defense. Even this formerly front-line weapon is currently being replaced by new missile systems, such as the Rolling Airframe Missile, which is smaller, faster, and allows for mid-flight course correction (guidance) to ensure a hit. To bridge the gap between guns and missiles, Russia in particular produces the Kashtan CIWS, which uses both guns and missiles for final defense. Two six-barreled 30 mm Gsh-6-30 gatling guns and 9M311 surface to air missiles provide for its defensive capabilities.

Upsetting this development to all-missile systems is the current move to stealth aircraft. Long range missiles depend on long-range detection to provide significant lead. Stealth designs cut detection ranges so much that the aircraft is often never even seen, and when it is, often too late for an intercept. Systems for detection and tracking of stealthy aircraft are a major problem for anti-aircraft development.

However, as Stealth technology grows, so does anti-stealth technology. Multiple transmitter radars such as those from Bistatic radars and Low-frequency radars are said to have the capabilities to detect stealth aircraft. Advanced forms of Thermographic cameras such as those that incorporate QWIPs would be able to optically see a Stealth aircraft regardless of the aircraft's RCS. In addition, Side looking radars, High-powered Optical Satellites, and sky-scanning, high-Aperature, high sensitivity Radars such as Radio telescopes, would all be able to narrow down the location of a Stealth aircraft under certain parameters.<ref></ref> The newest SAM's have a claimed ability to be able to detect and engage stealth targets, with the most notable being the S-400, which is claimed to be able to detect a target with a 0.05 meter squared RCS from 90 km away.<ref name="aus">Template:Cite journal</ref>

Another potential weapon system for anti-aircraft use is the laser. Although air planners imagined lasers in combat since the late 1960s, only the most modern laser systems are currently reaching what could be considered "experimental usefulness". In particular the Tactical High Energy Laser can be used in the anti-aircraft and anti-missile role. If current developments continue, someTemplate:Who believe it is reasonable to suggest that lasers will play a major role in air defense starting in the next ten years.

The future of projectile based weapons may be found in the railgun, currently tests are underway on developing systems that could create as much damage as a BGM-109 Tomahawk, but at a fraction of the cost. In February 2008 the US Navy tested a magnetic railgun; it fired a shell at Template:Convert per hour using 10 megajoules of energy. Its expected performance is over Template:Convert per hour muzzle velocity, accurate enough to hit a 5 meter target from Template:Convert away while shooting at 10 shots per minute. It is expected to be ready in 2020 to 2025.<ref>Template:Cite web</ref>Template:Verify source These systems while currently designed for static targets would only need the ability to be retargeted to become the next generation of AA system.

Naval AAW

[[File:AK-630 30 mm naval CIWS gun.JPEG|thumb|Soviet AK-630 CIWS (close-in weapon system)]]

Image:BGT IDAS.jpg
Model of the multirole IDAS missile of the German Navy, which can be fired from submerged anti-aircraft weapon systems.
Smaller boats and ships typically have machine-guns or fast cannons, which can often be deadly to low-flying aircraft if linked to a radar-directed fire-control system radar-controlled cannon for point defense. Some vessels like Aegis cruisers are as much a threat to aircraft as any land-based air defense system. In general, naval vessels should be treated with respect by aircraft, however the reverse is equally true. Carrier battle groups are especially well defended, as not only do they typically consist of many vessels with heavy air defense armament but they are also able to launch fighter jets for combat air patrol overhead to intercept incoming airborne threats.

Nations such as Japan use their SAM equipped vessels to create an outer air defense perimeter in the defense of its Home islands, and the United States also uses its Aegis equipped ships as part of its Aegis Ballistic Missile Defense System in the defense of the Continental United States.

Some modern submarines, such as the Type 212 submarines of the German Navy, are equipped with surface-to-air missile systems, since helicopters and anti-submarine warfare aircraft are significant threats. The subsurface launched anti-air missile was first purposed by US Navy Rear Admiral Charles B. Momsen, in a 1953 article.<ref>"Will the New Submarines Rule the Seas?" Popular Mechanics, August 1953, pp. 74-78, see page 78.</ref>

Area air defense

Area air defense, the air defense of a specific area or location, (as opposed to point defense), have historically been operated by both armies (Anti-Aircraft Command in the British Army, for instance) and Air Forces (the United States Air Force's CIM-10 Bomarc). Area defense systems have medium to long range and can be made up of various other systems and networked into an area defense system (in which case it may be made up of several short range systems combined to effectively cover an area). An example of area defense is the defense of Saudi Arabia and Israel by MIM-104 Patriot missile batteries during the first Gulf War, where the objective was to cover populated areas.


[[File:Amd sa15.jpg|thumb|The Russian Tor missile system can engage targets while moving, thus achieving high survivability.]] Most modern air defense systems are fairly mobile. Even the larger systems tend to be mounted on trailers and are designed to be fairly quickly broken down or set up. In the past, this was not always the case. Early missile systems were cumbersome and required much infrastructure; many could not be moved at all. With the diversification of air defense there has been much more emphasis on mobility. Most modern systems are usually either self-propelled (i.e. guns or missiles are mounted on a truck or tracked chassis) or easily towed. Even systems that consist of many components (transporter/erector/launchers, radars, command posts etc.) benefit from being mounted on a fleet of vehicles. In general, a fixed system can be identified, attacked and destroyed whereas a mobile system can show up in places where it is not expected. Soviet systems especially concentrate on mobility, after the lessons learnt in the Vietnam war between the USA and Vietnam. For more information on this part of the conflict, see SA-2 Guideline.

North Korea (officially the DPRK) has inherited a lot of older Soviet equipment. One major reason for the success of the U.N. forces during the Korean War (1950–1953) against the Korea was the air superiority they were able to attain. As tensions still exist on the Korean Peninsula and Korea is so heavily militarised, their air-defense network is amongst the strongest of a non-superpower. A large part of it consists of a number of older, fixed systems like SA-2, SA-3, and SA-5, but DPRK is also in possession of many mobile systems that have proven deadly in the past.

Air defense versus air defense suppression

The U.S. Air Force, in conjunction with the members of NATO, has developed significant tactics for air defense suppression. Dedicated weapons such as anti-radiation missiles and advanced electronics intelligence and electronic countermeasures platforms seek to suppress or negate the effectiveness of an opposing air-defense system. It is an arms race; as better jamming, countermeasures and anti-radiation weapons are developed, so are better SAM systems with ECCM capabilities and the ability to shoot down anti-radiation missiles and other munitions aimed at them or the targets they are defending.

SUW - Surface Warfare

MCM - Mine Countermeasures

NSW - Naval Special Warfare

INT - Naval Intelligence Gathering

OOTW - Operations Other Than War

Support Activities

In addition to specific missions, four "support activities" are defined; naval air operations (NAO). replenishment at sea (RAS). weapon systems reload (WRL) , and maintenance and repair (MAR). These activities are performed either during, or in direct support of, the naval missions. Another feature of these activities is that they generally use specialized equipment (e.g. aircraft, RAS gear. etc.), or they use "standard" equipment in a manner not directly associated with its normal operation (e.g. aiming and firing a CIWS is an AAW mission activity, whereas reloading the CIWS is a WRL support activity).

Naval Air Operations (NAO)

Naval Air Operations (NAO) is usually an important component of ASW and RAS, and it is also often associated with TAP. AAW. SUW, and MCM missions. In terms of seakeeping effects on performance, NAO involves a special and fairly consistent set of systems, tasks and criteria which must always be considered:

  • aircraft take-off and landing;
  • near-ship operations (e.g. VERTREP, and helicopter in-flight refueling (HIFR»; and,
  • on-deck handling (e.g. fuelling, folding wings or rotors, transit into hangar).

The seakeeping assessment of NAO activities is confined to ship motion related effects, but it is important to identify mission and system dependencies to determine how the interaction between ship and aircraft can impact operations. For example, ship motions do not directly affect the detection performance of air-dropped sonobuoys, but this task cannot be accomplished at all if the aircraft cannot take off from the ship. Alternatively, the ASW mission effectiveness can be reduced if the aircraft "turn around" time is increased by difficulties in refueling the aircraft, or loading its weapons and sensors.

Many naval ships do not have aircraft which are based on the ship, but they do have a capability for VERTREP and also possibly for helicopter refueling, resupply and/or emergency recovery. Thus, some aspects of NAO may have to be examined for ships which do not have shipboard aircraft. Similarly, a seakeeping analysis of ships which use remotely piloted vehicles (RPV) must include NAO considerations.

Replenishment at Sea (RAS)

Replenishment at sea (RAS), also known as Underway Replenishment (UNREP), represents a wide variety of resupply activities, including:

  • Connected Replenishment (CONREP). where two (or more) ships are connected by flexible umbilicals and / or constant tension wire rigging to exchange personnel and supplies such as munitions and general stores. Modeling CONREP generally includes clearance for the moving cargo. on-deck material handling, and stowing the cargo within the ship;
  • Fuelling at Sea (FAS), where two (or more) ships are connected by flexible umbilicals to exchange fuel (a special subset of CON REP); and.
  • Vertical Replenishment (VERTREP). where a helicopter is used to lower personnel and/or materials onto the ship.

More details of RAS operations and equipment are provided in Chapter 6 on seakeeping criteria for general applications. Note that VERTREP is a near-ship naval air operation (NAO) activity, as mentioned previously.

Weapon Systems Reload (WRL)

This support activity describes requirements for reloading weapons and other launching systems, such as chaff counter measures and sonobuoys. In most cases. These reloading activities require interaction between personnel and unsecured and/or moving equipment (e.g. removing chaff rounds from a ready-use locker and lifting them to the launcher. or moving a torpedo-loading trolley from the hangar to a waiting helicopter). Limiting factors and criteria for personnel are discussed in Chapter 6; however. The general application of WRL criteria in seakeeping assessment can vary with circumstances. For example, consider CIWS reloading. If an AAW mission scenario is based on a short-term self-defense capability, then it may be reasonable to assume that the CIWS has sufficient ammunition for the task; however, if the same capability must be evaluated for sustained operations, then the relatively more motion-sensitive task of reloading the CIWS must be included in the evaluation.

For automated loading systems, such as guns with automatic-loading magazines, limitations on system reloading will most likely be associated with the replenishment (RAS) activity, as all of the munitions stored aboard the ship are usually located in the automated system. Any ship motion-related operational criteria for the automatic loading system should be used for WRL evaluation, but unless the automated system malfunctions, it is likely that operational criteria will be the more restrictive, Also, as mentioned earlier, reloading vertical launch system (VLS) missiles is a RAS activity.

Maintenance and Repair Activity (MAR)

Maintenance and repair of equipment are support activities which are directly associated with all missions. Most MAR activities are relatively straight forward, and the specific systems and procedures used on any ship will determine how to model the associated tasks and develop or select seakeeping criteria. Chapters 7 and 8 on seakeeping criteria will provide examples of developing MAR criteria.

Systems and Tasks

It is important to appreciate that virtually all naval systems are a combination of equipment and humans. This theme should be kept in the forefront of the seakeeping analyst's mind while performing seakeeping assessments.

The following description of systems and their interaction with the missions and special activities are provided for general guidance. Table 3.2 defines six general types of systems, and provides examples of each type.

System Types Examples
Weapons CIWS. guns. missiles, torpedoes, mines
Aircraft helicopter. fixed wing, RPV, VSTOL
Sensors radar, hull mounted sonar. towed array, VDS. IR sensors
Command and Control decision making. communications, data fusion
Counter Measures chaff. ECM/ESM. torpedo decoys. mine countermeasures
Ship Systems ship hull. propulsion. auxiliary systems, RAS gear
Table 3.2: System Types and Examples

Table 3.3 shows the Mission/System Matrix, which defines the systems that are used in the missions, and also emphasizes the interaction of these systems with the support activities.

Any particular Navy or ship may not have all of the systems listed in Tables 3.2 and 3.3, and so it should be used for general guidance.

fixed wing
surveillance radar
target/guidance radar
navigation radar
hull mounted sonar
towed array sonar
variable depth sonar
dipping sonar
infra red sensors
laser sensors
visual sensors
Command and Control
decision making
data fusion
Counter Measures
chaff launchers
torpedo decoys
mine countermeasures
Ship Systems
ship hull
propulsion systems
auxiliary systems
RAS gear
Table 3.3: Mission I System Matrix

Our Mission

During this course we will develop early stage concepts for a given naval mission. Let's begin by reading the mission requirements for the LCS and the FMS.

All naval vessels respond to more than one mission. The mission requirements are provided by the customer in the form of a requirements document. The designer's job is to translate these requirements into one or more ship concepts, so that the customer can choose the one that best fits his need.

The mission requirements are stated in some combination of a requirements document, a concept of operation, and a set of ROCs and POEs (required operating capabilities and Projected Operational Environment).


  • Memo: 5000 Ser N76/6456l0 dtd 8 July 2002, MEMORANDUM FOR THE PROGRAM EXECUTIVE OFFICER (SURFACE STRIKE)(PEO(S)), Subj: OBJECTIVES FOR FAMILY OF SHIPS CONCEPT STUDIES, Focus Mission Ship (filename N00024-02-R-2306 Att J-4.pdf)
  • Littoral Combat Ship Concept of Operations Navy Warfare Development Command January 2003 V3.1 (filename: 03R2309 Attach J-8.1 LCS CONOPS.doc)
  • Littoral Combat Ship (LCS) CONOPS (filename: 03R2309 Attach J-8.2 LCS CONOPS.ppt)
  • LCS ROCs (page 89++ of filename: Douangaphaivong_thesis.pdf)


  • Read the handouts
  • Make sure you know what ALL the terms mean
  • Make a list of 25 adjectives (or adjectival phrases) that capture the required operating capabilities of the LCS

Acquisition & System Engineering Paradigm

  • Fleet composition and legacy: Naval ships don't work alone
  • Naval Ship and System Design and Acquisition Process with Case Study
  • Naval Standards & Rules
  • System Architecture and Integration
  • Platform vs Payload

Analysis of Alternatives and Measures of Effectiveness

Ready to Design a Naval Ship?

Read Keane / Fireman / Hough, 2008 In class discussion:

  • p.2 / para 1
  • p.2, GAO Quote
  • p.6, first para of section "Integrated Tools"
  • p.7, Lean Design Processes. What is "Lean"? Where did it come from? How does it apply to design?
  • p.8, discuss list in detail

First Pass: Architecture


  • FMS J-5 Modular Architecture (filename: N00024-02-R-2306 Att J-5 reqts.doc )
  • LCS J-5 Mission System Architecture Requirements (filename: 03R2309 Attach J-5.doc )


  • Read the mission package descriptions
  • Read the CONOPS
  • Convert the mission system descriptions into tables of space and weight required
  • See if there is a logical "clump" of two missions, for example where two smaller missions are the same size as one larger mission.

Add manning segue into manning calculations hand them a machinery baseline develop a building block arrangement as homework


  • Design Metrics – Cost/Effectiveness/Risk

  • Measures of Performance (MOPs)
  • Pareto Frontier
    • Draw Pareto Frontier for all ships in resulting dataset

A problem with the Pareto frontier is that any optimum of this sort is likely to severely constrain service life.

  • Analytical Hierarchy Process (AHP) and Multi-Attribute Utility Theory (MAUT)

    • Calculate an AHP weighting from a survey (IN?)
  • Overall Measure of Effectiveness (OMOE)
    • Use SPI & Cost & Risk & No. of Missions
  • Overall Measure of Risk (OMOR)
  • Basic Naval Operations Models
  • Naval Engineering Technologies and Problems
    • Design drivers:
      • Weight driven
      • Volume driven
      • Length Driven - "What is the minimum length ship in which you can fit the following systems..."
  • Naval Ship Synthesis Model and Project
      • Using design synthesis program from 3171, converge a design on weight
        • All 3 missions
        • Any 2 missions
        • Any 1 mission
        • "What is your stack-up length for a the 3-mission ship?"

Design Process: Ship Architecture

  • develop a ship building-block arrangement for LCS

Naval Ship Technologies

SWBS 000

    • Speed
    • Range
    • Speed / Time Profiles
    • Seakeeping
    • Ship Survivability
    • Susceptability
      • Radar Cross Section






ref: A New Iterative Method to Calculate Radar Cross Section of Complex Objects (05997080.pdf)

        • Bounce
        • Trihedrals
        • Principal planes
        • Fuzzballs & spikes

      • Acoustics
        • Basics of noise generation
        • Basics of transmission damping (structure)
        • Basics of ocean propagation
        • Ocean background noise
    • Vulnerability & Recoverability
      • Weapon effects
      • Deactivation diagrams and FMEA
      • Probability
      • Statistical simulations
    • Naval Ship Subdivision and Arrangements
    • Stack gas flow

Key concepts:

        • dB
        • Tonal vs Broadband
        • Role of thermoclines
        • Environmental aspect
        • Fish & Mammals

HW problem: Specify the mass for a double mount.

    • Reliability, Maintainability and Availability (RM&A) Analysis
    • Naval Ship Topside Design and Integration
    • Modularity and Flexible Architecture
    • Ship Production and Producibility
    • Total Ship Integration and Impact of New Technology
    • Naval Combat Operations Models
    • Ship motion effects upon mission effectiveness

Develop motion limits set for mission xxx. Using one hull, deformed, what is the SPI for mission xxx, for your 1-mission, 2-mission, 3-mission ship?

SWBS 100

    • Structural Systems - See excellent ISSC report (2012) at:[2] (file r13.pdf)
    • Underwater Explosion (UNDEX) Analysis
    • Dynamic Design Analysis Method (DDAM) and Shock
    • Structural Fatigue

SWBS 200

    • Naval Ship Power and Propulsion Systems
      • GT
      • Diesel
      • Nuke
      • Steam
      • COGAS
      • COGASE
      • Int. Electric
      • Diesel Electric
      • COGEL
      • CODLAG

SWBS 300

    • Integrated Power - Analysis, Quality of Power, Safety, Reliability, Survivability

SWBS 400

    • Command and Control Systems
    • System Maintenance
    • Automation Systems and Reduced Manning

SWBS 500

SWBS 600

    • Manning, Automation and Human Systems Integration
    • Human Factors

SWBS 700

    • Naval Ship Combat Systems
      • As associated with each mission
      • Impacts of system upon the platform
      • Given a list of missions, assemble a C/S suite
    • Flight decks - clearances etc. per NAVAIR Bulletin 1
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