The cruiser future in the RMN - another go

Relax wrote:True, we do not know precisely the true length of the MK-16 to be 15.01m long. We do know they are close.

Again with the "we". Don't presume to speak for me. I *know* the length of the Mk-16.

Relax wrote:Erm, I didn't make up that number. I inferred the number from your drawings and from the books when DW gave the length of the laser head.

Then you inferred incorrectly.

Relax wrote:As far as I am concerned anytime one can "guesstimate" anything within 25%, it is good enough. Especially for all of the SWAG'ing we do here on the forums.

But you didn't "guesstimate". You stated that "We have dimension for the MK-16 at 15m." That is not a guesstimate. That is couched as a statement of fact as you see it, which happens to be incorrect. As I said earlier, others did a much better job than you at "inferring" the dimensions from my meshes.

Relax wrote:And no, my 15m is certainly not cannon. It is just ~~~ Mheh, close enough.

There's a saying about "close enough".

Relax wrote:Regarding hole size in armor: It is the exact same. Outside of the total that is. Just means you get to place the slightly displaced armor elsewhere. Difference between a circle and an ellipse is .... nothing other than the angle. Take a circle and rotate it an angle and viola you have an ellipse. So, actually, the angled tube would be a SMALLER hole to a true perpendicular broadside shot as more passive armor would be in the way of the shot.

.... Flip a coin, what is your pleasure, maximum protection from a perfect broadside shot, or max protection against an angled shot...

Except that the hole in the armor isn't a circle. It's an oval, and for a good reason other than aesthetics. There is other, missile-related equipment there that must be exposed.

Also, a circle rotated to create an ellipse *would* have the same area, but the smaller dimension in an ellipse created that way would be smaller than when it was a circle. This means that the missile wouldn't fit through it.

Try creating an ellipse whilst keeping the small dimension the same as the original diameter of the circle, and you'll find the ellipse has more area than the circle. Hell, I didn't even take geometry in high school, and I know that.

In this case, what you're doing is *not* rotating a circle, but stretching it longitudinally. That increases the area, which, in turn, increases the vulnerable opening.

Edit: Try this experiment at home. Calculate the area of the end of a paper towel or toilet paper tube. Now, cut the tube at an angle. Unless you're looking at it straight from the end, you see an ellipse. Measure the area of the ellipse, and tell me (with a straight face) that its area isn't greater than that of the original tube opening.

kzt wrote:

MaxxQ wrote:Back to the topic at hand, another reason that angled tubes won't work is because you would need a larger opening (longer but not not taller), which would increase the vulnerability of the hull in those areas. By mounting them perpendicular to the long axis of the ship, you reduce the size of the hole in the main passive armor to the bare minimum.

The whole launcher sits in an armored bathtub capable of largely containing a multi-megaton explosion at contact range. So I'd argue that the size of the hole in the skin armor is pretty much insignificant.

I disagree. IMO, what it does is *limit* the amount of damage going elsewhere in the ship, not prevent it. If the internal armor was so strong as to "largely contain" a multi-megaton explosion, then why not build the rest of the ships armor from that and not ever worry about missile hits?

There's a reason that weapons ports are as small as possible - it decreases the odds that a laserhead hit will hit it directly. A larger hole means better odds of hitting the fragile (relatively-speaking) internal equipment.

MaxxQ wrote:Edit: Try this experiment at home. Calculate the area of the end of a paper towel or toilet paper tube. Now, cut the tube at an angle. Unless you're looking at it straight from the end, you see an ellipse. Measure the area of the ellipse, and tell me (with a straight face) that its area isn't greater than that of the original tube opening.

~25% from inferred, means could be between 15 and 20m long. Hardly a deal breaker in an argument.

You missed the point regarding the armor. I directly stated the volume is slightly greater. Multiplied by the inverse of the cosine of the angle. Does this extra excavated armor tonnage disappear? No. You get to place it on around the hole. It is therefore thicker through there. Therefore the actual thickness of the armor is effectively the same. Sure, the radius of the scarfed armor from angling is slightly greater, but effectively it is the same.

End effect is the exact same hole diameter through the armor with exact same amount armor, but for the true broadside shot, the hole in the armor is effectively smaller for a 100% miss of all armor as the narrow of the ellipse is the longitudinal direction and the height of the ellipse obviously is the height of the missile tube. By doing this it effectively requires a shot to hit some armor, even if it is thinner if one did not place that extra back around the angled holes internal/external lips. The Hole will look like this: () instead of o if the parenthesis and the lower case 'o' were the same height.

Why? would require a shot to go through the sidewall at an angle to hit the missile tube opening and pass into the interior without hitting the physical armor. This is a GOOD thing as the Sidewall is far better at diffusing deflecting the energy than any physical armor. Of course this is really pointless as I stated earlier because the cosine of 15 is still 0.967 or so. Therefore for all intensive purposes those "()" look indistinguishable from the 'o' until one gets up into around 30 degrees at which point, your missiles, are hitting your own wedge and going KABLOOEY. Not a good option.

Relax wrote:

MaxxQ wrote:Edit: Try this experiment at home. Calculate the area of the end of a paper towel or toilet paper tube. Now, cut the tube at an angle. Unless you're looking at it straight from the end, you see an ellipse. Measure the area of the ellipse, and tell me (with a straight face) that its area isn't greater than that of the original tube opening.

~25% from inferred, means could be between 15 and 20m long. Hardly a deal breaker in an argument.

You missed the point regarding the armor. I directly stated the volume is slightly greater. Multiplied by the inverse of the cosine of the angle. Does this extra excavated armor tonnage disappear? No. You get to place it on around the hole. It is therefore thicker through there. Therefore the actual thickness of the armor is effectively the same. Sure, the radius of the scarfed armor from angling is slightly greater, but effectively it is the same.

End effect is the exact same hole diameter through the armor with exact same amount armor, but for the true broadside shot, the hole in the armor is effectively smaller for a 100% miss of all armor as the narrow of the ellipse is the longitudinal direction and the height of the ellipse obviously is the height of the missile tube. By doing this it effectively requires a shot to hit some armor, even if it is thinner if one did not place that extra back around the angled holes internal/external lips. The Hole will look like this: () instead of o if the parenthesis and the lower case 'o' were the same height.

Why? would require a shot to go through the sidewall at an angle to hit the missile tube opening and pass into the interior without hitting the physical armor. This is a GOOD thing as the Sidewall is far better at diffusing deflecting the energy than any physical armor. Of course this is really pointless as I stated earlier because the cosine of 15 is still 0.967 or so. Therefore for all intensive purposes those "()" look indistinguishable from the 'o' until one gets up into around 30 degrees at which point, your missiles, are hitting your own wedge and going KABLOOEY. Not a good option.

Turn your parentheses on their side, and you would have the shape of the hole for a horizontal launch tube angled out the side of a cylinder. Your vertical parentheses means a vertical launch tube in the side of a cylinder. Granted, the opening doesn't open up much more, but it *is* still an area increase in the opening, and no matter where one distributes the "extra armor", a hit in the hole is still a hit in the hole. Smaller hole, even if by a tiny bit, means smaller chances of a hit going into the hole.

And as far as I'm concerned, next time you want to guess within 25%, you might want to state that, instead of stating your guess as fact. Frankly, I couldn't care less how you came by the number, or even what the number was. What irritated me was that you presented it as a fact, when it, in fact, wasn't.

Relax wrote:PS. Guess both Mk-23 and 16 do run along at 46,000g. I swear there was a quote in AAC with 96,000g for the MDM, but a quick search in AAC did not find it so...

That's in AoV:

The new multiple-drive missiles Ghost Rider had produced could have made the entire attack run at 96,000 gravities rather than stepping down to the 47,520 KPS2 at which they actually bored in.

A bit of a mess, since the latter figure should probably be either 48,000 gravities or 4.752 km/s2.

JeffEngel wrote:In addition, as commerce raider or commerce protectors, the BC is going to be fighting on a moving battlefield that it will not control long after a victory there, and one which may be in hyperspace or even a grav wave. (Rarely, yes, but not so rarely as to have strictly zero legitimate impact on design.) Picking back up pods won't be easy or possible there, so a BC(P) can lose effectiveness over time more easily, and it won't be able to use pods in a grav wave at all. The BC(L) won't be using its missiles there either, granted, and the BC(P)'s aft hatch is going to be well protected by the aft sail, but the broadside energy weapons will finally have a use again and the BC(L) is going to be much better able to fight in that environment in general design.

I didn't see this address in the rest of the thread, but I don't see how the sail is going to be protected by the aft sail. The sail projects (perpendicular to the long axis of the ship) out from the alpha node ring -- so the aft hammerhead sticks out past the aft sail.
That give a whole hemisphere behind of the ship where an attacker has an 'free' shot at the rear hammerhead (where the pod doors are) stuck out behind the aft sail.


Normally ships forced to fight in a grav wave use their chase armaments (to avoid exposing their broadsides (and alpha nodes) to fire) -- but a BC(P) should be leery of exposing it's stern to fire in that kind of fight. Not only could a hit eviscerate it's pod bay (removing it long range firepower once it clears the 'wave), but it could blow through into the concentrated and vulnerable vitals forward of the pod bay. So attempting to run (or letting the enemy pincer you) seems especially problematic for an BC(P).

JeffEngel wrote:For that, you're not really talking about an on-mount crew. Heck, locked into the weapon mounts, those crews represent the worst case for the floating damage control capability you're bringing up here.

Sort of yes, sort of no. Advantage is that they´re so spread out that some will survive as long as the ship survives, especially thanks to being in no air compartments. And as we know from the books, they are not glued to their seats, but can be sent off to enact repairs if need be.

Not sure where you got the assumption that those crews must stay firmly glued to their posts?

JeffEngel wrote:You could surely make the mounts themselves more durable without provision for work spaces in them.

Bad bad idea. The work space isn´t there just for onmount crews, but to allow easy maintenance and repair without the ship having to get to a dock.

JeffEngel wrote: In fact though, I think you would do better still putting some or all of those personnel (by count, not specifically) aboard other ships or in the Marine Corps than in damage control.

If you want the largest force possible, probably yes. If you want the largest CAPABLE force, then almost certainly NO!

JeffEngel wrote:And for that matter, I've got high hopes that miniaturization and automation will work as force multipliers for the DC and prize crews too, allowing them to do as well or better with no more or fewer people - and that the cruiser will be the sort of ship to make the most out of those advances.

Doubt it. Some things, it´s just extremely hard to replace humans when some jobs needs to be done.

And based on the books, i think they´ve already gotten about as far as they easily can.

The best they can do is probably improving armour and shielding even more.

JeffEngel wrote:Having more crew able to roam does; having more crew locked in there, not so much. And if you take that much damage there, so that all likely routes of control to the system are lost - what are the odds that you will still have a working weapon, working power for it, and a working crew on it?

Again, based on what we´ve seen in the books, not too shabby odds i think. Damage is often of the "needlethin" kind, slicing through relatively smallsized areas.

JeffEngel wrote:Well yes - this is an area where we're both more disagreeing with RFC than we're disagreeing with one another.

Oh the blasphemy!

JeffEngel wrote:It probably does not help either that the BC(L) is so much larger than the BC(P) and likely that much more expensive, proportionately, at least.

Yeah, BCPLs might be funny...

JeffEngel wrote:I've just been re-reading At All Costs and the use of light warships by Eight Fleet has been a bit perplexing. (This is less about the BC's of either sort than the CA's, CL's, and DD's.) I'm not talking about the excellent - textbook even - use of light cruisers for recon and carrying messages up into hyper. I'm talking about the CA's, CL's, and DD's moving out with the fleets in-system. The addition to point defense is meager; they're not maneuvering to extend the sensor net (RD's and LAC's have that covered); they're not contributing to firepower or even assuming control of any missiles in excess of control capacity of launching units. Mostly, when missiles lose lock, the smaller warships are serving as decoys with people aboard, with very little hope of withstanding any hits from capital ship missiles.

I think this is case of "old tradition and doctrine" meeting new realities before anyone has truly realised just how different a reality it is.

It can certainly be argued though that having the extra "viewpoints" for point defense, does add something more than just their meagre defenses looks like on paper, but overall yes, not the best of tactics.

But with everyone having those old ways of doing things completely ingrained, it would probably take a loot to shake their heads enough for them to notice and change doctrine.

JeffEngel wrote:It's hard to believe that they could not have done more good scouting in the low hyperspace bands for hidden fleets, using ECM to pretend to be more wallers or just BC's coming in from a different part of the system periphery early on, gaslighting the defenders of more star systems with recon for attacks that wouldn't take place, outright raiding the least-defending systems, commerce raiding, or just being sent out to Silesia or Talbott. Anyway, pardon the tangent.

Yup.

And it´s rather funny that i get the gaslight reference just because i started following a fanfic a few months ago.
(where in a nonmagic alternate universe, Hermione Granger gaslights a serial murderer into suicide(by Diane Castle on tth, awesome series))

And that´s MY little tangent...

JeffEngel wrote:I suppose the BC(L) is harder to misuse, but goodness, you can avoid promoting to admiral people who will make that sort of mistake.

*LOL*

And yes, the BCL definitely fits RMN style better.

JeffEngel wrote:And a BC(P) or two is likely an excellent way to do rear-area defense, as a worthy successor to the RHN's battleships. Even if it's overwhelmed, it's got an excellent chance of being able to leave the system without ammo but alive, to support retaking it and certainly to have exacted a high price out of a small force for taking it.

Quite true indeed.

JeffEngel wrote:I was talking specifically about the in-system fleet screen and recon role. Hyper-space capable drone tending is precisely the sort of place where it overlaps the CL role - and the CL, built for more endurance and stores, is going to do that better than the DD.

Yeah, but noone will build a CL that doesn´t have combat as at least one of its main abilities, meaning it requires much more of everything to be at all viable.

As in probably well more than twice as expensive to operate.

A nextgen DD as i see it would mainly be expected to be able to fight LACs or pirate ships, and otherwise mostly just be a hypercapable ship that can do things that a courier ship cannot.

JeffEngel wrote:DD role, CL role - abandon the tonnage associations. The RMN certainly has. I'm assuming that even miniaturized Keyhole I is going to take something in the 300 kton range, but more likely the 400 kton+ one, and that broadside DDM fire is going to take something about the size of a Saganami-C. That puts the hypercapable warship floor up into the 400-500 kton range, and whatever you're going to call it, it's going to be that large.

That´s where i expect the "CL" to end up.
Which is why there probably will be a need for a "DD" as well, without the frills needed to fight in any kind of big battle involving fleets or MDMs in any real numbers.

JeffEngel wrote:If you're figuring an effective warship can do without Keyhole I or that it can be miniaturized a lot more and if you figure that the Roland's hammerhead launchers will remain entirely acceptable or that the effective smallest hypercapable warship can still do without DDM's, then you figure on a much lower warship floor than I do. I'm not sure where we may differ on the relevant assumptions. I suspect we're differing on how we want to use the 'destroyer' and 'light cruiser' labels.

Keyhole, yes that just wont fit realistically as it is now into anything small enough(well some kind of limited version may be possible).
Hammerhead launchers, probably yes, though i expect a 200-300kt DD could fit some as a broadside, question is if they even should, the hammerhead launchers is a negative yes, but they also potentially allow a lot of "free" space alltogether in one in the middle.
DDMs is a must have, because sooner or later, pirates will find a way to pick SOME of those up at least.
Also, a streakdrive ASAP.

JeffEngel wrote:Yes. And I don't think there's enough demand for that warship to bother with a design for it in a major navy. Better to use something that can do other things too, so that DD role gets absorbed into the CL one.

It´s the major navies that will need it. And because of how much you´re going to squeeze into those CLs, they´re going to be expensive.

And trying to have enough of them to always have what you need? Unrealistic.

JeffEngel wrote:If there's only one major warship niche there belong the insouciant, cruiser-killing, wall-fleeing BC, the light/heavy cruiser distinction won't remain. I'm just betting that the role of it is going to resemble the current light cruiser's more than the heavy's, and the size of it current CA's (or old BC's!) more than anything else current.

Yes, which is why you´re going to need something smaller as well, as when your standard cruiser is 500kt, and you just need to dispatch something to be your eyes and ears in nearby systems, trying to send cruisers everywhere is just going to be too expensive.

And there will also be the "to valuable to risk" effect for those cruisers to at least some extent. There´s also the issue that sending a single ship into unknown places is NEVER a good idea(random chance, ambush etc), which would then mean that your minimum scouting force ends up as a megaton of cruisers for every place you need checked.

Have not followed the entire thread but there is one thing I would like to put out there, of the 'current' RMN designs the only satisfactory one is the BC(L). Of the older designs, the Avalon is appearantly highly rated. If the RMN is looking for price efficiency, in a 'low threat' enviroment, i.e. one where nobody is going to be able to produce more than Catapheracts deployed from CAs, and assuming that the LERM can be mated with a CA killing head, they might consider producing a Keyhole-lite equipped Avalon, under the designation of escort cruiser, that or they might build more Kammerlings, if they Sag b tubes, after giving them keyhole lite and two weapons decks. Not that it is likely, but the RMN used to have loads of FGs for close to the same reasons.

By the time the RMN has designed, built a test model, tested it, and approved it for series production it is highly likely that everyone they care about will have MDMs. And much better missile defenses, tactics, operational art, recon systems, and perpetration aids.

So yeah, designing a new ship that doesn't take that into account would be highly foolish.

If the point is that a notional 300kt ddm equipped vessel is still not worth building on the grounds that the capability differential vis a vi its larger siblings for the potential duties it might be called upon to do is to much, then the solution might be to build something which is just as well, if not more so, defended, while being cheaper, and still more than any exSLN CA can tussel with. This is not a warship, this is a military escort vessel.