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A collection of posts by David Weber containing background information for his stories, collected and generously made available Joe Buckley.

Counter-missile pods and two-stage counter-missiles

CM proposal. A proposal for using some sort of advanced CM pods has been bruited about. The idea (as I understand it) is to produce specialized ships, dedicated to carrying the heaviest possible anti-missile defenes and no offensive weaponry. They would be analagous to the Aegis-class cruisers in the sense that they would provide control links to very large numbers of CMs -- apparently equipping said CMs with FTL com links. Moreover, the CMs in question (apparently because of advances Manticore has made in missile propulsion) would have drives which either were (a) 2-stage, with one wedge, with a smaller drive, to get the missile out to engagement range or (b) a single-stage drive which can be reconfigured from a small wedge to a large one. (And, by the way, when you use the term "over-powered wedges" and talk about area of effect and acceleration rate, just how critical to their acceleration rate is the power of the wedge? In other words, is the wedge "over-powered" primarily to make it a better "sweeper," or is that design feature also required to enhance acceleration rates?) The idea for the drive changes suggested above, apparently, is to get greater endurance and to reduce the size of the wedge and thus reduce the "gunsmoke" effect. The idea is that these things would be fired in pods from the specialized ships (or perhaps from any ship in the fleet, I'm not clear on this) and be controlled by said specialized ships. The individual proposing the idea feels that this could be done in something enough smaller than a drone to be launchable in clusters from cannisters in standard "SKM" tubes. Whether he is proposing that they be fired from any SKM-capable tube or only from tubes large enough for all-up MDMs I do not know. I believe that it is in the same thread that there has been some dispute over whether or not these ships would divert from waller construction and, if so, whether or not it would be considered worthwhile by the RMN to build them.

The above summary raises some reasonable questions/speculations, but overall, it's a no-go. First, there's no need in the Honorverse for an Aegis-analogue. When the United States Navy deployed Aegis, it did so by creating specialized units designed to carry the necessary sensors and computer systems to make the entire system work. In effect, they created something analogous to the command datalink ships in Starfire. But the Honorverse doesn't face the same constraints. Essentially, any ships are capable of performing -- and routinely do form -- complex data linkages which weave entire squadrons and task forces, even fleets, into precisely coordinated, multi-platform [tactical] units. There are, of course, limitations. You're talking about exchanging a tremendous amount of information, and communications light-speed lags can also impose serious constraints. That's why it's not uncommon for a particular ship to be assigned particular responsibility within the datanet. The ships so assigned are managing specific functions, specific zones for missile defense, etc. Now, there are some significant differences. Aegis was designed to coordinate the defensive umbrella of an entire task group -- effectively, controlling any missile in the "basket" of the task force's engagement envelope. In the Honorverse, ships do not normally swap off control of their missiles in the sense that one ship "takes over" the control links on a missile or missiles fired by another ship. Instead, in the Honorverse, the coordinating ship assigned responsibility for, say, the outer counter-missile zone, handles targeting priorities, assigns a given target to a given ship, and then monitors the overall situation and performance of the missile defense. Recent innovations in Manticoran point defense have changed this somewhat, however. Current RMN warships are being built with additional control links. Those links are capable of assuming control of counter-missiles "handed over" to them by other ships, which permits a ship which is better placed to see the incoming attack missiles to actually engage them with other ships' counter-missiles. There are still limitations on how effective this is, because of the traditional problems of wedge interference and "gunsmoke," but it is a step towards evolving a more effective counter missile capability in the face of pod- sized salvos. It is, however, unlikely in the extreme that the Manticorans will ever build a dedicated anti-missile ship. There's no need to do so, given the capability already built into their existing vessels and the fact that they have deliberately spread the capability over all of the Navy's hulls. In practice, they have sought the survivability of their anti-missile capability by dispersing it, instead of concentrating it, and nothing in the current technology pipeline is likely to change that. They will undoubtedly continue to look for even more effective ways to integrate cooperation and shared capability, but this is an approach they are extremely unlikely to undertake. In reference to the last point raised in your summary of this thread, yes, the construction of specialized ships most definitely would divert construction capability from wallers, which is one of the reasons it's not going to happen. Another reason it's not going to happen, however, has less to do with construction capability -- which the SKM is far, far from having maxed out at this point -- to the question of how you man the construction once you've built it. The advances in automation accepted aboard the RMN's combatants has, indeed, gone a long way to reducing their manpower requirements. At the same time, the proliferation of LACs has pushed up manpower requirements in certain specific areas. And the fact remains, that building one of these specialized defense ships would require an investment in trained manpower pretty much equal to the manpower requirements of a pod superdreadnought. Platform operating expenses would also be equivalent. Money per se is not the governing factor in Manticoran construction policies at this time, and neither is scarcity of building capacity. They are having to ramp up construction capabilities -- by reinstating their use of dispersed yards once more -- and I'm not trying to say that the economic/resource allocation side of their building decisions isn't significant. But the governing factor is their requirement for trained personnel. Not just missile technicians, or reactor technicians, but trained, experienced bridge officers. Tactical officers. Electronic warfare officers. These are very precious commodities at the moment, and will be for the foreseeable future, and Manticore is unlikely to tie up either building capacity or trained manpower in vessels which have no offensive capability and do not significantly contribute to the enhanced defensive capability for the Maybe as a whole.

There is no way you could possibly get useful numbers of counter-missiles -- especially with any of the drive modifications suggested above -- into a "canister" deployment approach. No way, no how. To dispose of the second suggestion first, I had hoped that the notion that missile drives could be fiddled with this way had been knocked soundly over the head years ago. I will reprise one more time: Once a missile drives's initial power setting has been selected, it cannot be changed. Missiles are not drones. In order to get the necessary performance out of them, a missile drive is expressly designed and engineered to be fired up -- once -- at a selected power range -- only. Neither the power setting, nor the geometry of the wedge, can be altered once it comes up in the first place. To change this would require a fundamental breakthrough which has not been made. The fact that it hasn't been made explains why anyone is bothering with multi-drive missiles at all.

The two-stage proposal would be workable from an engineering viewpoint, but only if you wanted to accept counter-missiles larger than your shipkiller missiles, which strikes me as a questionable bargain. Honorverse missile defense is based on the premise that a certain, quite possibly large, percentage of your defensive missiles are going to fail to take out the incoming hostile missile which you launch them to intercept. In other words, the entire reason that existing counter-missiles are designed the way they are is to permit warships to carry them in sufficient quantity to mount a sustained, credible defense. In order to build a counter-missiles which would have (1) the twin drive capabilities you've described, (2) the sensor capability to acquire, track, and intercept hostile missiles at a range which would make the drive capabilities useful, and (3) the ability to build in an FTL two-way communications link to permit the firing ships to control them usefully at extended range, you would require something larger than existing recon drones, and they are already quite large. To give you an idea, the standard Manticoran counter-missile as of War of Honor, masses about 12.5 tons. Havenite counter-missiles are about 25% larger, and individually less capable despite their greater size. A single-drive capital ship missile runs to about 135 tons, or better than ten times the size of a single counter-missile. The remote platforms being deployed by the RMN these days, which would approximate the minimum size capable of squeezing in the proposed drive arrangement, are over twice the size of an old-style capital missile, which is why they are deployed by swimming them out of boat bays rather than firing them through tubes. So, let's assume that you could build one of these things for "only" 270 tons. In that case, each of them would replace something like 22 standard counter-missiles. Not a good trade in the opinion of the missile defense officers.

The over-powered, out-sized wedges used by current-generation in counter-missiles are required both because of the "sweeper" function (as you put it) and also to achieve the accelerations currently being achieved. The counter-missiles being used by the RMN have benefited from the incremental increases in the capability of the multiple drives engineered into the MDMs. Their acceleration rates are greater than they were, which is one reason for the expansion of the effective counter-missile envelope, but part of the "price" they pay for their acceleration rate is the size and power of their wedges. In fairness, no particular effort has been made to reduce the size of the wedge [since], as I stated (again) above, once the wedge goes up, it cannot be further adjusted before burnout. That being the case, and given that the designers want the widest "burn" they can get, all efforts have actually been directed towards expanding the size of the counter-missile wedge, rather than attempting to shrink it.