Valiant vs Avalon

Weird Harold wrote:LDDMs are an interim design to give dual drive tactical options to legacy ships (and new design smaller ships) without requiring extensive modifications.

As originally conceived, LDDMs were also a second tier, non-GA, missile for LACs in the system defense role.

The main advantage of the LDDM design is that it is doable NOW and in a package roughly compatible with existing launchers. It doesn't require extensive cofferdams or new technology.

LDDMs and CDDMs are not as capable as Mk-16's but they are more capable than the capacitor missiles they are based on. They give ships armed with LERM and ERM missiles an option of dual drive tactical flexibility without the need to drop down a warhead size as the Cataphract design does or extensively modifying existing ships.

This, I have no quibbles with at all. It's quite true that a LDDM would be an interesting upgrade for existing ships armed with LERMs or standard SDMs. They would likely still give away a bit of terminal velocity compared to the slightly longer-running drive on a LERM, but not enough to be decisive compared to their longer ranges. (I don't have drive figures on the LERM, but postulating that it adds an extra 30 seconds of drive time (210s total) it would have a powered range of 9.9 million km and a terminal velocity of 94,668 km/s - not really *that* much of an improvement on the LDDM's 81,144 km/s and 244s of flight time to cover the same distance.)

I'm just saying that I would rather put a Mk16, rather than a LDDM, on a *new design* Avalon-B. But really, I actually would rather put a DD/CL DDM on it, now that the idea has occurred to me.

One last thought: RMN warheads are bigger, more powerful on a missile class basis. Especially since the development of the Mod e(1)/Mod-G warheads for the Mk-16s. I don't think LERM/LDDM missiles will be as outclassed by Cataphract-As as you think they would be.

This is true - a cataphract-A has a standard DD/CL warhead, while a LDDM could concievably carry an Mk16-esque upgraded RMN warhead - but it's really somewhat tangential to what I'm really talking about, which is the advantages of a true DDM format compared to the LDDM format. It is indeed germane to the particular comparison of LDDM vs cataphract-A, though, and I'll give you that. I still think a cataphract-A vs LDDM fight will go to the cataphract-armed ship, but probably not by as much as I was thinking.

I don't think it currently is possible to shrink a micro-fusion plant any smaller that the Mk16's.

It's definitely somewhat of a stretch, but honestly I don't think we have enough information to say anything definitive one way or another. We just don't know how small a microfusion plant can be built - it might not be possible, but on the other hand, it might. I will certainly admit it may not be possible with current tech, but if it *is* possible then I think it's probably the answer to the question of 'what should a DD(L) or CL(L) be armed with?' And so:

Avalon-B CL(L) (DD/CL DDM version)
Mass: 300,000 tons
Dimensions: 521 x 63 x 53 m
Acceleration: 759.6 G (607.7 G at 80%)
Broadside: 16M, 6G, 10CM, 16PD
Chase: 2G, 8CM, 8PD

Total Crew: 220 (~90 marines - two platoons)
Shipkiller Missiles: 1280 Mk38 DD/CL weight DDM
Fire Control: 96 Mk38, 108 CM
Hull space and hardpoints to limpet ~25 flat-pack pods
Standard alliance two-phase bow and stern walls and full off-bore targeting

This variant assumes that it is possible to build a DD/CL weight fusion-powered DDM - essentially, a hypothetical 'Mk38 DDM' missile that is to the Mk36 LERM what the Mk16 DDM is to the (immediately preceding) CA/BC Mk14 ERM. Based on comparing the size of a Mk16 with the CA/BC Mk13 missile, *if* it is possible to miniaturize the microfusion reactor sufficiently to fit it into a DD/CL diameter missile body, then it should be possible to create a DD/CL fusion powered DDM that is no more than 15-20% longer than a Mk36 LERM, similar to how the Mk16 looks like it is perhaps 15-20% longer than the Mk13. With a smaller missile and smaller reactor requiring less startup power a Mk38 launcher should similarly be much smaller than a Mk16 launcher - still bulkier than a Mk36 launcher, but able to fit into a DD(L) or CL(L) hullform similar to how a Mk16 launcher can fit into a CA(L) or BC(L) hullform.

This version of the Avalon-B still is capable of full off-bore targeting like the Saganami-C and Nike, so it can put a double broadside of 32 missiles into any aspect. It breaks with the typical modern RMN pattern of not placing any countermissile launchers in the hammerheads, but this is simply because there isn't enough room in the broadsides with the number of missile tubes. (The broadsides will have more room since this version of the design won't have disproportionately oversized hammerheads like the Roland or Mk16 Avalon-B version, but still not enough to jam in *16* missile tubes without removing something else.) With off-bore targeting it doesn't really *matter* where on the hull the countermissile launchers are, so while this design puts them in slightly different places than the previous, it still has the same overall number of countermissile launchers. It does sacrifice two PD laser clusters in each broadside, but the weight of missile broadside is probably worth it.

(Also, as an aside, I've heard mention several times of a 'missile spreadsheet' (and, for that matter, a ship acceleration spreadsheet) that some forum members have compiled. It would be really helpful for us theorycrafters if those spreadsheets were available somewhere - I'd even just take an excel file if translating them to a google spreadsheet was too much of a pain. Would this be possible?)

I don't think that there will actually be a 300kt RMN CL that gets built. And I really don't think that the RMN will build a second type of fusion DDM, one smaller, lighter, and less capable than the Mark 16.

I'm of the belief that the minimum baseline for any new hypercapable warship design that the RMN will build will have both some degree of Keyhole and broadside DDM capability.
The hammerhead DDM cluster arrangement is something that isn't going to be carried forwards into future generations of RMN warships. DDM capability is going to be the minimum standard. Some form of Keyhole will be highly desirable to the point of almost mandatory if you have it, as it massively upgrades survivability, and that will also have a minimum tonnage requirement - one that we don't have enough information on to determine.


The next generation of RMN warships, will, I believe, all be as big or bigger than a Sag-C.


Especially if there's any possibility of getting any part of Apollo into Mark-16 compatibility.
Actually ... you could probably get the FTL receiver and some computers in, but you'd need to rely on Ghost Rider drones for the FTL feed going to the ship - the missile would only be able to listen to the ship's FTL feed, it wouldn't be able to talk to the ship via FTL on its own.

MuonNeutrino wrote:As for Mk-16 vs Mk-23, those actually don't generate much difference in their terminal velocity as long as you're inside the Mk-16s (quite generous) powered range. Both of them still outrange SDMs, the Mk-23 just outranges them more.

Depends on what you mean by "much difference".

At those short ranges the Mk23 can choose an accel profile to take advantage of the full accel from at least one drive stage.

Assume you're aiming for a target at 29 million km.
A Mk16 would hit it by 2 drives at 1/2 power:
360 seconds at 46,000g:
Range: 29.2 million km
Terminal Velocity: 162,288 km/s (0.541 c)
Flight time: 6 minutes

But a Mk23 could it hit by 2 drives at full power + 1 drive at 1/2 power.
120 seconds at 92,000g + 160s
Range: 29.5 million km
Terminal Velocity: 180,320 km/s (0.601 c)
Flight time: 4 minutes, 40 seconds)

(Yeah, you could run the Mk23 on the same accel profile as the Mk16 but, unless you were coordinating simultaneous fire from Mk23 and Mk16 units to swamp point defense from sheer numbers, there seems little reason to)

MuonNeutrino wrote:(I don't have drive figures on the LERM, but postulating that it adds an extra 30 seconds of drive time (210s total) it would have a powered range of 9.9 million km and a terminal velocity of 94,668 km/s - not really *that* much of an improvement on the LDDM's 81,144 km/s and 244s of flight time to cover the same distance.)

My working guess is that it has the same range at the Mark 14 ERM - which from a couple difference places seems to be around 16 million km; which if true requires an additional 90 seconds of 1/2 power flight time and gives a terminal velocity around 121,716 km/s (0.406 c)

Kytheros wrote:I don't think that there will actually be a 300kt RMN CL that gets built. And I really don't think that the RMN will build a second type of fusion DDM, one smaller, lighter, and less capable than the Mark 16.

I'm of the belief that the minimum baseline for any new hypercapable warship design...

I dunno. *If* it's possible, and *if* it allows them to build true DDM capability into sub-Sag-C sized ships without the Roland's oddball arrangement, and *if* they decide to build ships that small, then I could see them doing it.

But, like you said, it depends on whether they decide to build any further ships of such small sizes at all, and that's definitely up in the air. Really all we're doing here is piling speculation on top of speculation, only RFC knows for sure what the RMN will decide to do and he ain't telling. I'm just taking the hypothetical 300 kt CL(L) ball and running with it to see where it goes.

Jonathan_S wrote:Depends on what you mean by "much difference".
...
Terminal Velocity: 162,288 km/s (0.541 c)
Terminal Velocity: 180,320 km/s (0.601 c)

Yeah, that's more or less what I meant by 'not much difference'. It's an improvement of ~10% over the Mk16, compared to the Mk16's improvement of ~70-100% over the LDDM.

I'm surprised that the Mk14 would have *that* much range. That's not just an extended drive, that's 3/4 of the way to a full-on DDM endurance. Out of curiosity, where have you seen figures for the Mk14?

Edit: I found a discussion of missile ranges in Service of the Sword, during the prelude to the battle with the pirate CAs (Gauntlet is a Sag-B and so should have the Mk14), but they're a complete hash. None of the numbers make any sense from what I can tell, it's like this was a passage that got mangled in editing or rewriting and slipped through into the final version. It's talking about missiles with powered endurances of only 90 seconds instead of the standard 180, powered ranges at launch of only ~15 million km when the closing velocity of 60,000 km/s would be enough to add 10 million km to the powered range at launch of any missile with a 180s endurance, and just in general the numbers don't seem to make sense with each other. Are there any other figures on Mk14 missiles that you're aware of?

Kytheros wrote:However, I don't foresee fusion powered countermissiles or Vipers. Capacitor power works just for anything that's a single drive missile - especially CMs.

True, I don't see any need for fusion-powered single drive missiles of any scale -- especially if component life rather than power availability is the decisive factor on range.

What I can see, if "micro-fusion" can be further reduced to "Pico-fusion," is dual-drive or multi-drive CMs and Vipers.

One of the problems with current anti-missile doctrine is a lack of range for CMs that limits the number of CM salvos that can be fired. Dual-Drive for CMs would let ships fire CMs as soon as they detect a hostile missile launch and meet the enemy missiles over half-way to the enemy ships and provide time for multiple follow-on CM launches.

Whether CMs just add the capability of a ballistic phase before a final powered attack at extended range or dounble or triple their powered range, being able to meet hostile missiles further from the defending ships would be an advantage.

MuonNeutrino wrote:I dunno. *If* it's possible, and *if* it allows them to build true DDM capability into sub-Sag-C sized ships without the Roland's oddball arrangement, and *if* they decide to build ships that small, then I could see them doing it.

But, like you said, it depends on whether they decide to build any further ships of such small sizes at all, and that's definitely up in the air.

I can't see the RMN leaving a gap in ship size and capability between LACs and Rolands. They would lose the "smaller is faster" edge that DDs and CLs have traditionally had over CA-and bigger.

MuonNeutrino wrote:I'm surprised that the Mk14 would have *that* much range. That's not just an extended drive, that's 3/4 of the way to a full-on DDM endurance. Out of curiosity, where have you seen figures for the Mk14?

I think the figures are from the Erewhon-built Mk-17 copy of the Mk-14 sold to Maya and used in the battle with the PNE at Torch.

Weird Harold wrote:

MuonNeutrino wrote:I'm surprised that the Mk14 would have *that* much range. That's not just an extended drive, that's 3/4 of the way to a full-on DDM endurance. Out of curiosity, where have you seen figures for the Mk14?

I think the figures are from the Erewhon-built Mk-17 copy of the Mk-14 sold to Maya and used in the battle with the PNE at Torch.

Hmm. Looking through that section, unless I missed it RFC doesn't give the actual max range/flight time. We do get a snippet that they have an accel of 451 km/s^2, which is the same 46,000 g that I was using before. But we also get a snippet that after opening fire the flight time for the Mk-17E was going to be 217 seconds, so they've got *at least* 37 extra seconds of drive endurance, and from the way they were describing things they had significantly more range than that and were mostly closing range to get the best accuracy they could.

So, they've got more than the 30s of extra endurance I was postulating, but *how* much more? 60s of extra endurance would give them a range of 12.9 million km from rest, while 90s would (as Jonathan_S notes) give them a range of 16.4 million km from rest. It still seems weird for them to have a full 3/4 the endurance of a DDM, but maybe?

Weird Harold wrote:

Kytheros wrote:However, I don't foresee fusion powered countermissiles or Vipers. Capacitor power works just for anything that's a single drive missile - especially CMs.

True, I don't see any need for fusion-powered single drive missiles of any scale -- especially if component life rather than power availability is the decisive factor on range.

What I can see, if "micro-fusion" can be further reduced to "Pico-fusion," is dual-drive or multi-drive CMs and Vipers.

Can't quite see some form of multi-drive Viper happening, it's already pushing quite a few limits. It's incredibly smart, on a ton for ton basis smarter than any other missile including Apollo.

Offensively, Viper's are so dangerous and "smart" due to being practically in their targets laps and their acceleration leaves little reaction time. And an MDM format actually wouldn't really help all that much, except to give the target a little more time to try to shoot them down, without increasing much.

In a defensive role you're spending even more than you are with the SDM Viper's shooting down incoming fire on you. But there has to be a spot somewhere, that even Manticore is going to look at and think "ok, this is crazy and even WE can't afford this", they're already thinking that about punching SDM Viper's at missiles. But Vipers cost less than entire starships (and their crews), but an MDM Viper may not be that cheap.

MuonNeutrino wrote:

Weird Harold wrote:I think the figures are from the Erewhon-built Mk-17 copy of the Mk-14 sold to Maya and used in the battle with the PNE at Torch.

Hmm. Looking through that section, unless I missed it RFC doesn't give the actual max range/flight time. We do get a snippet that they have an accel of 451 km/s^2, which is the same 46,000 g that I was using before. But we also get a snippet that after opening fire the flight time for the Mk-17E was going to be 217 seconds, so they've got *at least* 37 extra seconds of drive endurance, and from the way they were describing things they had significantly more range than that and were mostly closing range to get the best accuracy they could.

So, they've got more than the 30s of extra endurance I was postulating, but *how* much more? 60s of extra endurance would give them a range of 12.9 million km from rest, while 90s would (as Jonathan_S notes) give them a range of 16.4 million km from rest. It still seems weird for them to have a full 3/4 the endurance of a DDM, but maybe?

There's a lot more inference in trying to work out the Mk14 ranges than the other missiles. You're correct that RFC never gives their runtime; we just get their accel.

But I was infering from a couple data points, one that Weird Harold pointed out from ToF. I swear, though I'm having trouble finding it at the moment, that there was a later discussion where Rozsak thought or said that he'd screwed up by getting too close and that his Mk17Es actually had more range than the Cataphracts he was facing (and we know from Duckk that those have 16.5 million km range)

Also in Shadow of Freedom when planning for a simulation against improved range missiles (with only knowing Roscak should have had ERMs but having no details on the Cataphract he'd faced, jumped to 16 million km - then bumped to 17, as a plausible number that the refs might grant the simulated SLN missiles). Seems weak, but plasuble, they might well have judged that off the ~16 million km the

And finally, in WoH there's the combat between Jessica Epps and Hellbarde which was conducted using extended drive missiles (not that they were called that in the book) at 15 million km.


But like I said, this is weaker evidence than what we have for most other missiles. And most ERMs seems to be bumped a mere 15 (or 45) seconds at full (of half) power.

Jonathan_S wrote:I swear, though I'm having trouble finding it at the moment, that there was a later discussion where Rozsak thought or said that he'd screwed up by getting too close and that his Mk17Es actually had more range than the Cataphracts he was facing (and we know from Duckk that those have 16.5 million km range)

I looked, but I can't find this one either - it might be in some later book instead?

And finally, in WoH there's the combat between Jessica Epps and Hellbarde which was conducted using extended drive missiles (not that they were called that in the book) at 15 million km.

I went through some of this section of WoH, unfortunately I think you may have misremembered as the range was only 10 million km between Jessica Epps and Hellbarde, which doesn't tell us much that we don't already know.

I think you may be remembering a slightly later discussion instead, where Honor and Mercedes Brigham are discussing a different incident between manty and andy forces. That describes a fight between a manticoran CA and three andy CLs, and says that the manty CA (which had to have been a pre-mk16 design given when War of Honor takes place) opened fire at 15 million km. Unfortunately, we don't know anything about the geometry of the engagement - that much range *from rest* would suggest an endurance of at least 260 seconds, but even 12,000 km/s of closing velocity would allow for a 240s duration missile (range from rest of 12.9 million km) to reach out to over 15 million km range at firing (and there ought to have been *some* closing velocity given the description), so it's difficult to draw any hard conclusions.

There is one point, though, which was that the andys were reported to have returned fire at 12 million km, and implying that that was their maximum range (and that it was presumably longer than they 'should' have had with single drive missiles). And that means that the closing velocity couldn't have been much *more* than about 12,000 km/s, since even that much adds more than 2 million km to a missile's range. If the closing velocity was any higher, than a range at firing of 12 million km would translate to a range from rest of less than 10 million km, which is less than the range that Hellbarde fired at Jessica Epps from (in an engagement where, from context, we can gather that the closing velocities were likely small). So, we can probably say that a Mk14 has at least 240 seconds of endurance, otherwise it wouldn't have been able to reach out to the 15 million km at which the manty CA fired given that we can put a rough upper limit on the closing velocity.