Three-stage vs. two stage multidrive missiles

I'm wondering how much point there is to the three stage missile design versus the two stage ones, and I don't have the information to make that judgment. So I'm hoping others may have it and/or insights.

My nagging suspicion is that the three stage missiles may be a bit extravagant for most purposes versus the two stage ones, but that depends on my guesses that (1) it's not a trivial additional cost in space, payload, and monetary cost, and (2) having the third stage available doesn't add too terribly much in tactical virtue.

(1) is a guess, but it's pretty confident - that third stage makes the difference between something limited to pods and wallers and something fit even for specially designed destroyers to use. (2) is more contentious.

Obviously, a third stage gives a longer powered range and a higher maximum velocity, especially without having to dial down acceleration for a longer burn. But a ballistic component in between powered stages gets you stupendous range anyway - as much as your ability to control the missile way, way down there and your time and range allow. The typical long range attack seems to run powered burn, ballistic phase, final approach - and for that, a third stage is nothing more than more burn time, if even useful, on one of the first two stages.

So it looks like a capability with fairly limited use at significant expense. This leads me to suspect that wallers and missile pods could quite possibly be better off, most of the time, using capital-missile-sized dual drive missiles, or at least some variant that is in between the cruiser DDM's and the current MDM's, with the costs of the third stage spent instead on more warhead, more missiles, more penaids, and/or longer running stages.

Soooo... am I missing something or did Manticore leap to an excessive multidrive missile and mostly stick with that model since then?

You suggest that most MDM battles include a ballistic phase for the missiles, but that is not true. MDM ranges are so long that accuracy degrades drastically at the outer limits of powered range--even with Apollo. Before Apollo, targeting at extreme power range was almost useless. Almost no MDM battles have included a ballistic phase. Honor's attack in BoM I is an exception, dictated by the fact that she would have been unable to get into powered range in time.

The additional speed provided by the third stage should not be underestimated. That extra speed helps quite a bit in degrading the enemy's active defenses. Counter-missiles and PDLCs have even less time to target the missile, and a harder time tracking it at that speed.

A ballistic phase gives the enemy extra time to figure out where your salvo is going. The missiles have to be aimed in the general direction of your target when the first stage cuts off. If you had continuous power, you could delay the point at which you give away your general target until later in the trajectory.

A third stage is a lot more useful than you think. Whether it is worth the cost is perhaps a matter of opinion, but my reading is that it is worth it. I doubt that a capital-sized DDM would be so much cheaper and smaller than a capital-sized MDM that it makes up for the added agility of the MDM.

JeffEngel wrote:I'm wondering how much point there is to the three stage missile design versus the two stage ones, and I don't have the information to make that judgment. So I'm hoping others may have it and/or insights.

My nagging suspicion is that the three stage missiles may be a bit extravagant for most purposes versus the two stage ones, but that depends on my guesses that (1) it's not a trivial additional cost in space, payload, and monetary cost, and (2) having the third stage available doesn't add too terribly much in tactical virtue.

(1) is a guess, but it's pretty confident - that third stage makes the difference between something limited to pods and wallers and something fit even for specially designed destroyers to use. (2) is more contentious.
[snip]

I think you're overestimating the size impact of the 3rd drive.

Also, while it appears that the MAlign Cataphract design is a true 2 stage missile (the first stage complete with 'normal' missile drive appears to be left behind when the 2nd stage with its CM drive lights off) the Manticoran (and Havenite) designs are multi-drive missiles.

They don't drop anything off, they just have somewhat longer drive sections at the missile rear that have 2, 3 (or, in the case of the new RMN system defense missiles, 4) node rings in close proximity (protected from each other by the grav "baffle")


So once you go to a microfusion powered missile (like the RMN have) you need a little extra fuel for the reactor, and maybe another meter or two of missile length for the additional drive node rings. Havenite capacitor powered missiles take a bigger size hit because the capacitors needed to run those extra drives take up a lot more space than the extra fuel needed to run a reactor that long. (And they use cruder tech, so they were larger than Mantie missiles to begin with)

But remember even Manticore's capacitor powered 3 drive missiles were capable of being launched from tubes. HMS Minotaur, the prototype CLAC, carried some and used them at Hancock. The Medusa, Harrington, and Harrington II SD(P) classes all carried MDM tubes in both their broadside and forward hammerheads. Also some Gryphon-class SDs were (heavily) refitted to launch MDMs from their tubes.


So overall I think you're weighing the costs of a 3rd (or 4th) stage too heavily. It's not that big a driver of size.

Some points to consider:

1) Most of the tech breakthroughs are getting more than one drive to work at all, the diff between 2 and >2 drives is minor once you have fusion powered missiles.

2) Against a range limited opponent, 2 drives is enough in most situations, although 3 does allow for full accel salvos, which could be a significant tactical advantage. I suspect this is why the Buttercup era MDM's had three drives.

3) If you anticipate even a remote chance of facing a similarly armed opponent, it's best to design for the future. Better to have ships that can immediately use the capability when needed than ships that need time in the yards before they can.

4) I suspect that even in the late pre-Buttercup era the Project Gram R&D types were anticipating what would become Apollo, and the ability to actually use most of the range of an MDM accurately.

5) It's been said by RFC in various ways that the biggest cost of things like missiles is the industrial plant. I suspect the incremental cost difference between 2 and 3 drives is minor, especially for fusion powered birds. It also allows commonality with System Defense hardware. never underestimate the benefits of having only a single missile to manufacture for both ships and system defense.

SWM wrote:You suggest that most MDM battles include a ballistic phase for the missiles, but that is not true. MDM ranges are so long that accuracy degrades drastically at the outer limits of powered range--even with Apollo. Before Apollo, targeting at extreme power range was almost useless. Almost no MDM battles have included a ballistic phase. Honor's attack in BoM I is an exception, dictated by the fact that she would have been unable to get into powered range in time.

The additional speed provided by the third stage should not be underestimated. That extra speed helps quite a bit in degrading the enemy's active defenses. Counter-missiles and PDLCs have even less time to target the missile, and a harder time tracking it at that speed.

A ballistic phase gives the enemy extra time to figure out where your salvo is going. The missiles have to be aimed in the general direction of your target when the first stage cuts off. If you had continuous power, you could delay the point at which you give away your general target until later in the trajectory.

A third stage is a lot more useful than you think. Whether it is worth the cost is perhaps a matter of opinion, but my reading is that it is worth it. I doubt that a capital-sized DDM would be so much cheaper and smaller than a capital-sized MDM that it makes up for the added agility of the MDM.

Not a fires officer, but here's two cents.

The active degradation you mention in your second paragraph has two elements--that there is less time for the missile defenses to activate, and that there is insufficient time for the defenses to self-correct if they miss. They CM get only one shop, and the missile crosses the laser-cluster's range too fast for more than one chance to target.

While the range of the attack prevents, forex, the SLN from counterattacking, isn't it the final velocity that renders their defenses inadequate, both in terms of the controlling software and the physical hardware?

Regarding Apollo, doesn't it have about the same delay at 4 light minutes that pre-apollo missiles had at about 4 light seconds? I thought it was because they didn't suffer the degredation that made them so dangerous?

Regards,

Rob

ericth wrote:Some points to consider:

1) Most of the tech breakthroughs are getting more than one drive to work at all, the diff between 2 and >2 drives is minor once you have fusion powered missiles.

2) Against a range limited opponent, 2 drives is enough in most situations, although 3 does allow for full accel salvos, which could be a significant tactical advantage. I suspect this is why the Buttercup era MDM's had three drives.

3) If you anticipate even a remote chance of facing a similarly armed opponent, it's best to design for the future. Better to have ships that can immediately use the capability when needed than ships that need time in the yards before they can.

4) I suspect that even in the late pre-Buttercup era the Project Gram R&D types were anticipating what would become Apollo, and the ability to actually use most of the range of an MDM accurately.

5) It's been said by RFC in various ways that the biggest cost of things like missiles is the industrial plant. I suspect the incremental cost difference between 2 and 3 drives is minor, especially for fusion powered birds. It also allows commonality with System Defense hardware. never underestimate the benefits of having only a single missile to manufacture for both ships and system defense.

But in fact they're running with a 4 stage (or 4 drive, if you really prefer) missile for system defense. I recall some complaints in text about the proliferation of ammunition types - they certainly do not have that under control, much as they'd like to.

Also - if the third drive does not represent much more trouble, why is it that they are using merely two drive missiles at all for the cruisers? Certainly the DDM was a stretch to fit into the Roland at all, but if the 3 drive missiles are that much better and not much harder to build - heck, if you're committed to them anyway and they're not much bigger than the DDM's - why not just build the Rolands a bit larger and fill them with a 3 drive missile, perhaps even the same missile you use on the larger ships and spare yourself one more ammunition type?

The sheer speed piled on top of speed justification for the third drive still holds, but if we accept that, then we'd have to figure that you'd go for a 3rd drive any time you practically can, which would suggest that the 3rd drive really is a significant cost in terms of missile size at least, thereby justifying the 2 drive missiles for sub-wallers.

Three stage missiles have bigger warheads and are harder to hit, but they're much bigger than two stage. Two stage are cheaper version for smaller ships. Good comparison of 203 mm gun and 356 mm and bigger.

JeffEngel wrote:

ericth wrote:Some points to consider:

1) Most of the tech breakthroughs are getting more than one drive to work at all, the diff between 2 and >2 drives is minor once you have fusion powered missiles.

2) Against a range limited opponent, 2 drives is enough in most situations, although 3 does allow for full accel salvos, which could be a significant tactical advantage. I suspect this is why the Buttercup era MDM's had three drives.

3) If you anticipate even a remote chance of facing a similarly armed opponent, it's best to design for the future. Better to have ships that can immediately use the capability when needed than ships that need time in the yards before they can.

4) I suspect that even in the late pre-Buttercup era the Project Gram R&D types were anticipating what would become Apollo, and the ability to actually use most of the range of an MDM accurately.

5) It's been said by RFC in various ways that the biggest cost of things like missiles is the industrial plant. I suspect the incremental cost difference between 2 and 3 drives is minor, especially for fusion powered birds. It also allows commonality with System Defense hardware. never underestimate the benefits of having only a single missile to manufacture for both ships and system defense.

But in fact they're running with a 4 stage (or 4 drive, if you really prefer) missile for system defense. I recall some complaints in text about the proliferation of ammunition types - they certainly do not have that under control, much as they'd like to.

Also - if the third drive does not represent much more trouble, why is it that they are using merely two drive missiles at all for the cruisers? Certainly the DDM was a stretch to fit into the Roland at all, but if the 3 drive missiles are that much better and not much harder to build - heck, if you're committed to them anyway and they're not much bigger than the DDM's - why not just build the Rolands a bit larger and fill them with a 3 drive missile, perhaps even the same missile you use on the larger ships and spare yourself one more ammunition type?

The sheer speed piled on top of speed justification for the third drive still holds, but if we accept that, then we'd have to figure that you'd go for a 3rd drive any time you practically can, which would suggest that the 3rd drive really is a significant cost in terms of missile size at least, thereby justifying the 2 drive missiles for sub-wallers.

Well classically you always had at least 4 missiles types:
1) LAC missiles
2) DD/CL missiles
3) CA/BC missiles
4)Capital BB/BN/SD missiles.

Even when they all had about the same range and the same accel the larger ships carried bigger missiles which had room for more (and more powerful ECM), larger warheads, and more lasing rods. That's some of what made the early pods so nasty, a BC or even a CA towing a few pods could fire off the equivilent of a broadside or two worth of capital ship missiles.

So the Mk16 DDM has a smaller warhead and fewer lasing rods than the Mk32 MDM; allowing BCs/CAs to carry more of them than the full sized 3 drive capital ship MDM. And I don't see any likelihood that Manticore looked for Capital missile equipped CAs (much less DDs). Now could they have built a 3 drive MDM around the same cruiser weight warhead that the Mk16 used? Yes, I'm sure they could have. It would have been bigger than a Mk16 but still smaller than a full up capital ship Mk32.
I suspect they avoided doing that partly because it would have put a further squeeze on the number of birds you could fit into a magazine, but also to further encourage commanders to avoid taking even BCs up against SD(P)s. (Same reason the Agamemnon-class BC(P)s routinely carry Mk16 pods rather than Mk23 pods - even though it's trivial to switch the type of pod carried)

JeffEngel wrote:Also - if the third drive does not represent much more trouble, why is it that they are using merely two drive missiles at all for the cruisers?

I can't find the textev off hand, but I recall a statement that smaller ships have smaller missiles to prevent the temptation to use them in the Wall instead of for their designed missions.

JeffEngel wrote: Certainly the DDM was a stretch to fit into the Roland at all, but if the 3 drive missiles are that much better and not much harder to build - heck, if you're committed to them anyway and they're not much bigger than the DDM's - why not just build the Rolands a bit larger and fill them with a 3 drive missile, perhaps even the same missile you use on the larger ships and spare yourself one more ammunition type?

The Rolands are already so big they're mistaken for light cruisers. Build them bigger and you sacrifice acceleration.

In House of Steel, it mentions that the Agamemnons are primarily loaded with Mk16s be cause they can fit 14 Mk16s in a pod, vs 10 Mk 23, or 8 Mk23 + 1 ACM. That translates to 40-45% more ammo at the expense of powered range.

Basically, the missiles, like the ships, are optimized for the missions, just as Wallers are optimized for generating and withstanding missile storms. Small ships are supposed to run from Wallers, not fight them; they're not supposed to get into situations where the need to generate missile storms, but they do need enough magazine space to undertake long missions without resupply.

Jonathan_S wrote:Well classically you always had at least 4 missiles types:
1) LAC missiles
2) DD/CL missiles
3) CA/BC missiles
4)Capital BB/BN/SD missiles.

Even when they all had about the same range and the same accel the larger ships carried bigger missiles which had room for more (and more powerful ECM), larger warheads, and more lasing rods. That's some of what made the early pods so nasty, a BC or even a CA towing a few pods could fire off the equivilent of a broadside or two worth of capital ship missiles.

So the Mk16 DDM has a smaller warhead and fewer lasing rods than the Mk32 MDM; allowing BCs/CAs to carry more of them than the full sized 3 drive capital ship MDM. And I don't see any likelihood that Manticore looked for Capital missile equipped CAs (much less DDs). Now could they have built a 3 drive MDM around the same cruiser weight warhead that the Mk16 used? Yes, I'm sure they could have. It would have been bigger than a Mk16 but still smaller than a full up capital ship Mk32.
I suspect they avoided doing that partly because it would have put a further squeeze on the number of birds you could fit into a magazine, but also to further encourage commanders to avoid taking even BCs up against SD(P)s. (Same reason the Agamemnon-class BC(P)s routinely carry Mk16 pods rather than Mk23 pods - even though it's trivial to switch the type of pod carried)

Actually, the system defense missile has also been a fifth classical missile type, even bigger than the capital missile. We saw an example all the way back in HoTQ when Blackbird launched them at Honor.