Build a modern battleship

[Cirov]

Your logic has some flaws.

1. A magnetic accelerator works pretty great actually.
2. About that rocket launch. I already stated acceleration to 1,000 feet per second in 50 feet is 310 G's. Double the distance to 100 feet and it drops to 155 G's. Do you really believe GLSDB is magic and doesn't encounter any stresses from it's rocket launch?
3. Complexity of the system is not an impossible hurdle. GLSDB already does a rocket launch, post-launch cruise under a decellation, then release and separation of the SDB as a submunition.

So, if you take two quotes from my post that were talking about different things, and seemingly don't read either of them, then yeah, you'll find some flaws in my logic.

1. Sort of. EMALS qualifies and is likely a better starting point--railgun projects tend to focus "low mass, high velocity," which is the opposite of what you want for an assisted rocket launch. But it's far from a solved problem. Rocket artillery is a solved problem, gun artillery is a solved problem--we can build another variation of either of those fairly quickly and easily. Figuring out a magnetic accelerator that sits vertical, is pretty short, and accelerates a 500 pound (ish) object to approx. 300 m/s is a whole set of new engineering problems. Maglev and EMALS throw a much lighter object much slower. How do you hold the projectile? If you use a sled, how do you slow it back down?

But, fair point, I suppose. A slow magnetic accelerator is a lot closer to real than a Mach 8 mega-gun.

2. Yes, I know. I have zero problem with GLSDB incurring 300 or 500 Gs. There's a line somewhere, but I'm not a rocket engineer so I'll just assume the line is around 500 Gs. This is where the reading comprehension comes in, because I said that already. We are talking about launch assist for a projectile very similar to GLSDB, and my entire thesis is that yes, you could draw benefit from an assisted launch, so long as the launch did not involve tens of thousands of Gs. A gun that is not a magnetic accelerator, recoilless or not, will incur thousands of Gs on launch, or it will be a cap gun that imparts no useful velocity. Therefore, either the projectile will not resemble GLSDB and will instead have a cost and payload profile similar to LRLAP, or we will have to invent a working magnetic accelerator first.

3. Completely irrelevant. No idea why you said that. The complexity I was weighing in on has to do with the comparative cost of LRLAP and Excalibur, neither of which remotely resembles GLSDB. Adding a rocket booster to a gun-launched projectile, which GLSDB is not, means designing a rocket motor and fuel system that can survive a 20,000 G launch. I think that process adds more cost to the projectile than some other users seem to think, and that it is not worth it compared to the effectiveness of firing a subcaliber munition, possibly with a gas generator, and with a rudimentary guidance unit.

With regards to the hypothetical GLSDB first-stage accelerator you're talking about, yeah, I think you're right. The complexity would not be a significant cost factor. The rocket booster would undergo a very similar force of acceleration as a normal hot or cold launch, so no trouble there. It might be SAFER: if the booster fails, the projectile is already accelerating towards the ship while moving very quickly away from it. To work optimally, you would just have to add a few seconds of delay so that the booster saves fuel until the initial velocity has been turned into altitude. Each one would still be more costly per payload unit delivered than artillery shells, but there is absolutely a role for cruise and ballistic missiles, and this one would get ahead on the cost curve thanks to the accelerator launch.

If you aren't talking about a gun-launch GLSDB, then my only argument is that gun-launched projectiles are going to be a lot more affordable, and you need that in a war.

 

[MadRat]

Since we are talking literally one of the most expensive warships in history, whatever it lobs needs to be from a large offset/displacement from the target.

 

[Cirov]

The primary threat to a surface ship from a sub these days is not the heavyweight torpedo. It's a sub-launched AShCM, like Harpoon, Tomahawk Block V, P-700 Granit, P-800 Oniks, or 3M54 Klub. Worse, Oscars or Yasens are volleying 24-32 of them at a time. Even a US sub is volleying up to 15 of them at you (mixed Tomahawks and Harpoons).

So you need pretty capable AA defenses on your "ASW frigate" or it's nothing but a target. Hence why Constellation had Aegis and SPY6 and was 7000tons.

The floor for minimum capabilities has gone up a long way since the Perry-class was designed, my dude.

I don't really think there's a mission profile for a sub-hunting FFG that doesn't involve AAW destroyers nearby. Most likely, the FFG is protecting a carrier group, which obviously has plenty of AAW. But even if not, a very good application of force for sub-hunting would be 3-4 ASW + 1 AAW. You need Aegis to defend from opportunistic strikes, but you don't need 5x Aegis.

And I'm pretty sure sub-launched missiles were a thing when Perry was designed.

Rocket boosted artillery shells are a solved problem. We've had them in active combat service since 1970 (US M549), and the concept goes clear back to 1941.

They're well understood. And heck, the Excalibur is a base-bleed shell, so it's got a tiny rocket motor already. LRLAP is an Excalibur with a full size rocket booster. Actually, I think LRLAP has a sleeker projectile shape as well, but it's still functionally an understood/solved problem. No reason for them to be stupid expensive, we're just using more materials to make LRLAP than Excalibur. Longer rocket casing, more thermal liner, more solid rocket propellant of a type we know how to make.

Solved, yes, but still expensive. And come on, you have to realize that a gas generator is WILDLY cheaper than a full-on thrust-vectored rocket motor. There is a world of difference between those two engineering problems. They are both solved, but bicycles and cars are both solved engineering problems, and one is more complex and therefore more expensive.

I'm not trying to shoot down rocket boosting. My big consideration here is cost, because cost correlates inversely with number of effects put on target, at least in this instance. Use a guided, rocket-boosted LRLAP equivalent when you aren't trying to flatten a hardened area target.

So drop the GPS enhancements and go strictly with an IMU. Better, have a weapons mode that is pure IMU with the GPS off for when there is heavy GPS jamming. All the guidance needs to know is where it started from and where it needs to go. Once the gun computer says "here is the expected course you will be flying" and sends it, the shell's IMU is comparing actual position to expected and correcting on the fly.

Yes, it will take more shells of 155mm than of 406mm. We can fire said 155s about 10x faster than the 406s. Equal amounts of boom is 6x 155s per 406.

My point was, GPS guidance up to the last meter of freefall is going to be the most accurate system. Replacing it the way you describe will solve the EW problem but will come at a cost of accuracy. Again, I don't doubt that the problem will be solved, I just point out that it imposes costs.

Equal amounts of explosive filler is 6x 155mm per 406mm. That does NOT mean equal effects. Bigger shells can penetrate better, and they get more "boom" from the same amount of filler by containing the explosion for a more rapid, complete detonation. Maybe LRLAP gets the same efficiency as a bigger shell, I just know that TLAM uses almost twice as much filler as a 16" HC and gets about the same, slightly smaller, effect radius.

Anyway, that aside. If you require 6x the 155mm shells for the same effects on target, since you can't rely on higher accuracy, and you are paying the same or more per shell, then you are going to spend 6x+. Right? Cost per effect on target is the whole thing I think a gun should minimize.

So, your objections are noted, but I think the product of this conversation is that a very large caliber gun firing saboted base-bleed projectiles with minimal guidance is the best form of strike. LRLAP and existing designs of cruise and ballistic missiles are unaffordable. They provide an advantage in range that we don't need.

 

[Explorer121]

If you really want a big cannon on a ship, I think that a single massive spinal cannon may be the way to go. You would have to use maneuvering shells, optionally with their own propulsion, but I think you could get enough range with something like that. Of course, then you have to compare it with the cost-effectiveness of guided missile destroyers/cruisers/battleships, and it ends up being a solution in search of a problem.

 

[Cirov]

If you really want a big cannon on a ship, I think that a single massive spinal cannon may be the way to go. You would have to use maneuvering shells, optionally with their own propulsion, but I think you could get enough range with something like that. Of course, then you have to compare it with the cost-effectiveness of guided missile destroyers/cruisers/battleships, and it ends up being a solution in search of a problem.

Isn't this a refutation of itself?

A spinal gun, oversized for the ship it is on, will have to fire expensive rounds with very complete guidance capabilities--they aren't just mildly adjusting to counteract unexpected forces, they are steering to a completely new trajectory. Changing trajectory like that burns up energy, so they are either going to accept a shorter range or pack rocket boosters like LRLAP. Halfway to a missile, and unlike a missile, the projectile experiences 15-20k Gs on launch, so the payload will be more like 5-10% mass rather than 50% mass like GLSDB.

So you build a ship that only carries 50 shells for its one gun, and each shell costs half as much as a TLAM with 10% of the effect on target and 20% of the range. Why did you do this? It's a complete misdirection of effort. You are trying to make a gun that launches a missile instead of working with the natural advantages of a gun. What problem does this even solve? Guided, rocket assisted rounds for the Army make sense, if you consider that packing 3-5 Excalibur or whatever with every 155mm battery is easier than putting HIMARS all over the front. But what does the Navy need with a gun that isn't as flexible as a missile nor nearly as cheap as a dumb gun?

Put a bunch of big, turreted guns on a ship. Minimal guidance, no rocket assist, sabot and base bleed to get extra range if you need it. The shells come out to 10% of the price of a missile, with 50% the payload and 10-20% the range. It uses the advantages of a gun to fit in its own niche. If the zone is too hot and you can't approach to with 150km, then use cruise/ballistic missiles from further away, that isn't a niche for a gun. Same if the target is landlocked and you can't physically approach close enough. But if the target can be reached with a gun, and it is a hardened target that will need several hundred warheads regardless of accuracy, then a gun is what you need. Not a gun that shoots mini-cruise missiles, not a first-stage booster that launches cheaper cruise missiles. A real gun, that works like a gun. The Army understands this: they didn't retire the Paladins when they invented MLRS, nor when they invented ATACMS, because a missile can't do everything a gun can do. Why is it so incomprehensible that the Navy could apply this same lesson?

Since we are talking literally one of the most expensive warships in history, whatever it lobs needs to be from a large offset/displacement from the target.

I'm not trying to be rude, but what is the point of engaging in conversation if you don't read or respond to the conversation?

My problem with your GLSDB-launcher proposal isn't the range issue, it's that you're still talking about a cruise missile. In particular, a low-speed cruise missile that will be shot down in droves during flight and terminal approach, very vulnerable to enemy superiority fighters and gun-based point defense. Absolutely, a magnetic accelerator for a low-cost cruise missile has value in certain niches, where you desperately need to stay at long range, or if you don't expect serious air defenses.

But it is not remotely the same niche as a gun, so it isn't an alternative to a gun. Magnetic VGAS for large-caliber cruise missiles does something besides what I think a battleship should do. I'm not shooting down your proposal on its own, you just keep insisting it is a better alternative to my proposal for a traditional gun system, so I have to keep saying that they are not in the same niche.

And you are missing the point that to develop your hypothetical battleship would be insanely expensive and losing it would be devastating and you have to get it within ~150km of the target, which means the enemy can use almost everything in their arsenal to hit you, and you are limited to targets near shore.

Was gonna leave this alone, but whatever.

By that logic, why did we develop aircraft carriers at all? Insanely expensive, shorter range than TLAM, devastating if we lose it.

In the example above, I showed my reasoning to believe that a strike of 1,000 shells could have an effect on target roughly similar to 400 PrSM or TLAM. I believe that the actual number of either missile could be 600 or 800, since they are much easier to intercept than tube artillery rounds, and since they are much less efficient with their payload. I also believe that the shells in question could be substantially cheaper than my estimate of $120,000 each. Therefore, I suppose that a strike could either cost approximately $120 million in shells, or $1.5-2 billion in missiles.

So, using shells produces costs savings of $1.4-1.9 billion. That is the cost of a whole ship, per strike. Developing a new warship is certainly costly, but two billion dollars per strike is a big number. 15 strikes in a war, which would be very low, is already the development cost of Zumwalt, a famously expensive warship. Quite obviously, leaning on ridiculously expensive missiles is the unaffordable option.

Getting close isn't a huge problem. The enemy has the range to hit you, but why did we design Aegis if not to protect our warships while they're being shot at? The enemy also can't shoot what it can't see, which is why I suggested a carrier escort. Carrier-based aircraft will create a bubble a couple hundred kilometers in diameter, shooting down drones they spot using passive sensors. Air Force-supplied long-range fighters will use AIM-174B or AMRAAM to shoot down anything foolish enough to radiate. Carrier-based aircraft will also be keeping a sharp eye out for incoming attack, again using passive sensors--if they spot a large missile launch with thermals, they know the jig is up, and everyone in the fleet needs to light up the radar systems and abort. Approaching the enemy is not impossible, and we do ourselves a disservice treating it that way. Furthermore, the shore is where the targets are--10% of the global population lives within 5 km of the coast. Naval bases, a prime target, are self-evidently close to shore.

And again, why bother posting in a conversation if you aren't reading the conversation? Literally nothing in here have I not already said. This isn't a comment section on Instagram, we are all participating in the same long conversation together, it is reasonable to expect people to read it before weighing in. Why else are we on an old school messageboard?

 

[MadRat]

Peak AMRAAM acceleration can be as much as 500 Gs if my math is right. Of course when launched off a moving plane they should be far less.

 

[Cirov]

Do you have a point or are you just saying?

I expect the acceleration would be roughly the same, just sustained for a shorter period since it'll reach terminal velocity faster. Reducing the acceleration would likely require throttling the motor, and there's no reason to do it since the missile can obviously already survive that G-force.

 

[CommanderRenHoek]

The problem is when you sacrifice overall ship counts. You might even say that every single Aegis system mounted on a ship costs us a dedicated ASW frigate. If we cut ASW capability off the Burkes and put it into its own ship, we could either have 10 of them WITH Aegis or 20 WITHOUT Aegis. Which is better?

Honestly, the ten Aegis ships, because you asked it as an "either/or" question. As Scott mentioned above, Aegis is non-negotiable in today and tomorrow's mass missile/high-end threat battlefields.

On Burke ASW fits: Except for the Technology Insert Flight IIAs that combine MFTA and helos, the majority of ships (Flight I, II, most of the IIAs and at least the first few III-2019s) already have partial ASW suites that have been compromised to some extent in the name of cost-cutting. I doubt more savings can be wrung by stripping them out completely, and making them more vulnerable to subs or UUVs will then put disproportionate pressure on the proposed ASW specialist class to protect both the AAW ships and the capitals.

A specialized ship does not imply a ship built with zero margin. More importantly, not every upgrade a navy wants to apply is a good one. Sure, you could say Perry didn't have enough margin because you couldn't fit a SPY-6 and 32-cell VLS onboard. But why should you want to do that? On the other side of the equation, you could say Burke was a great example of having plenty of design margin, because you could easily fit all the AAW equipment you need. But if that meant leaving ASW gear untouched and undervalued, did the ship really have enough margin?

Specialization doesn't necessarily mean zero margins, yes, but for much of the Cold War that was the case, especially over in the UK and Europe, because of the penny-pinching imperatives that pushed for specialization in the first place. While Spruance started out as an ASW ship, she was consciously built with weight margins and adaptability in mind as a result of the DX/DXG program envisioning upgrades/role expansions from ASW to AAW later in life.

You would want to upgrade the Perry class unless you are fine with disposing the ships quickly in under 20yrs of service because their Mk 13 GMLS + Mk 92 GMFCS could not be easily made to take SM-2MR. Perhaps that is what you would prefer, ideally having constant production of specialized ships to keep the industry more alive, but again that becomes a political-industrial exercise and one that has its own risks and challenges.

The Burke has also just about hit the maximum allowable upgradability with the basic design; Flight III 2019 is about as good as it'll get with that hull unless one tried to resurrect Flight III 1988, in which case just make a new hull. That's why they're trying to make the eventual successor, DDG(X), at least, before the drama with that design and the BBG(X) proposal came about.

In the example above, I showed my reasoning to believe that a strike of 1,000 shells could have an effect on target roughly similar to 400 PrSM or TLAM. I believe that the actual number of either missile could be 600 or 800, since they are much easier to intercept than tube artillery rounds, and since they are much less efficient with their payload. I also believe that the shells in question could be substantially cheaper than my estimate of $120,000 each. Therefore, I suppose that a strike could either cost approximately $120 million in shells, or $1.5-2 billion in missiles.

Slight objection, very-large caliber non-guided artillery (16-18", or even the saboted 12-13") are not necessarily harder to intercept than high-supersonic/hypersonic ballistic missiles like PrSM. Remember that Harpoon is 13" in diameter, SM-6 is 13.5", and PrSM is 17". 16-18" shells are very fast at terminal velocity but they're still big ballistic targets compared to 4-8" shells, and even those can be tracked (British Sea Wolf SAM did it in the 70s against 4.5" shells, even if it was just a demo). They're probably at least proof against autocannon-based C-RAM options.

So, using shells produces costs savings of $1.4-1.9 billion. That is the cost of a whole ship, per strike. Developing a new warship is certainly costly, but two billion dollars per strike is a big number. 15 strikes in a war, which would be very low, is already the development cost of Zumwalt, a famously expensive warship. Quite obviously, leaning on ridiculously expensive missiles is the unaffordable option.

Getting close isn't a huge problem. The enemy has the range to hit you, but why did we design Aegis if not to protect our warships while they're being shot at? The enemy also can't shoot what it can't see, which is why I suggested a carrier escort. Carrier-based aircraft will create a bubble a couple hundred kilometers in diameter, shooting down drones they spot using passive sensors. Air Force-supplied long-range fighters will use AIM-174B or AMRAAM to shoot down anything foolish enough to radiate. Carrier-based aircraft will also be keeping a sharp eye out for incoming attack, again using passive sensors--if they spot a large missile launch with thermals, they know the jig is up, and everyone in the fleet needs to light up the radar systems and abort. Approaching the enemy is not impossible, and we do ourselves a disservice treating it that way. Furthermore, the shore is where the targets are--10% of the global population lives within 5 km of the coast. Naval bases, a prime target, are self-evidently close to shore.

I agree that approaching the enemy is not impossible and indeed is necessary if you want to win.

But, if one is expending this much effort to try and shut down for a prolonged duration some notional "hardened area target" like naval bases, this is a major operation if not a "decisive battleTM", not a mere raid or medium-intensity NGFS mission like the CONOPS for Zumwalt. In such a context, the large gunship is a nice-to-have compared to the rest of the identified supporting elements, because as you've noted, successfully closing with a determined peer enemy to bombardment range requires all that support.

Sure, delivering 120 million USD in ballistic ordinance sounds cheap when compared to just the HE equivalent of PrSM/TLAM, but this same single operation is likely already burning through millions if not billions of USD in BVRAAM, SAM, ABM, ADM and AShM covering and offensive fires. Hell, even if just 10% of all that results in air and shipkills then you've caused major damage to the adversary anyway. In which case, maybe the cost tradeoff is not (large gunship and shell payload) vs (cruise/ballistic missiles) but either of those vs having enough BVRAAM, SAM, AShM etc. to force a decisive naval/air outcome (which may or may not hinge on that naval base still standing).

 

[MadRat]

Do you have a point or are you just saying?

I expect the acceleration would be roughly the same, just sustained for a shorter period since it'll reach terminal velocity faster. Reducing the acceleration would likely require throttling the motor, and there's no reason to do it since the missile can obviously already survive that G-force.

GLSDB and AMRAAM have roughly the same forces on them at launch. Just putting to bed the idea the an SDB cannot take a rocket launch.

 

[Cirov]

Honestly, the ten Aegis ships, because you asked it as an "either/or" question. As Scott mentioned above, Aegis is non-negotiable in today and tomorrow's mass missile/high-end threat battlefields.

I really just think that's a mindset of "follow the leader." Anti-ship ballistic missiles actually coming anywhere near a target is going to be rare. For anything else, cooperative engagement or just letting the AAW ring do its job is good enough. Sure, there's a risk that any ship could be targeted by a ballistic missile, and the Aegis-equipped defender is going to be too far away to help. But if we wanted absolute proof against that, you would give up on a Navy altogether, because fighting wars is a great way to lose ships. No fight, no losses.

I seriously doubt a missile sub is going to launch a coordinated strike that can get past a watchful Burke a kilometer or two away from the targeted frigate. If it spends that much time on a missile salvo (they do still launch a few seconds apart, right?) then won't it be very easily spotted by airborne ASW? And that's assuming the sub got a good track on the target in the first place, which is going to be difficult for a surface ship to do.

At the end of the day, I'm not a submariner, so I will concede if someone has credentials or sources. But none of this passes an intuitive glance.

Slight objection, very-large caliber non-guided artillery (16-18", or even the saboted 12-13") are not necessarily harder to intercept than high-supersonic/hypersonic ballistic missiles like PrSM. Remember that Harpoon is 13" in diameter, SM-6 is 13.5", and PrSM is 17". 16-18" shells are very fast at terminal velocity but they're still big ballistic targets compared to 4-8" shells, and even those can be tracked (British Sea Wolf SAM did it in the 70s against 4.5" shells, even if it was just a demo). They're probably at least proof against autocannon-based C-RAM options.

That's a very good objection, I should have been more careful. I didn't mean to lump PrSM into the category "easy to intercept." In my actual (rough) calculations, I didn't assume a different intercept rate--I upgraded PrSM and TLAM from 400 effectors to 600 or 800 based purely on warhead considerations. Namely, a 16" HC shell has an observed effect on target greater than TLAM, despite filler weighing a hundred pounds less, and my initial calculations up the thread levelized for total mass of filler.

So yes, in the end, I would say that PrSM and semi-guided large artillery probably have similar interception rates. Roughly similar terminal velocity and size. TLAM is the ugly duckling here, since it flies a trajectory that can be easily subjected to superiority fighter interdiction.

I agree that approaching the enemy is not impossible and indeed is necessary if you want to win.

But, if one is expending this much effort to try and shut down for a prolonged duration some notional "hardened area target" like naval bases, this is a major operation if not a "decisive battleTM", not a mere raid or medium-intensity NGFS mission like the CONOPS for Zumwalt. In such a context, the large gunship is a nice-to-have compared to the rest of the identified supporting elements, because as you've noted, successfully closing with a determined peer enemy to bombardment range requires all that support.

Sure, delivering 120 million USD in ballistic ordinance sounds cheap when compared to just the HE equivalent of PrSM/TLAM, but this same single operation is likely already burning through millions if not billions of USD in BVRAAM, SAM, ABM, ADM and AShM covering and offensive fires. Hell, even if just 10% of all that results in air and shipkills then you've caused major damage to the adversary anyway. In which case, maybe the cost tradeoff is not (large gunship and shell payload) vs (cruise/ballistic missiles) but either of those vs having enough BVRAAM, SAM, AShM etc. to force a decisive naval/air outcome (which may or may not hinge on that naval base still standing).

My theory there is that all of that stuff needs to be done anyway. Can't beat the enemy by needling him from long range. That wins positive kill ratios and loses wars. If we're serious about fighting a war, we're going to need to fight through the enemy's (alleged) A2/AD ring. All the SM-6 and ESSM and AIM-174 and lost planes and ships that we expend getting close enough to shell the enemy will result in killing the enemy, and hopefully make a positive tradeoff on its own. In other words, that's a whole different problem to evaluate.

We could save a LOT more money if we gave up on ESSM and carriers and fighters, and just built LCS to haul very long ranged missiles to a very safe point to lob at the enemy. But since we won't, and we have all these AAW warships full of missiles, carrier based planes, stealth fighters, tankers, bombers, we may as well actually USE them.

GLSDB and AMRAAM have roughly the same forces on them at launch. Just putting to bed the idea the an SDB cannot take a rocket launch.

There must have been a misunderstanding, then. It can take a rocket launch. I thought we were talking about a VGAS-type system for GLSDB, which would impart forces beyond a rocket launch.

 

[Scott Kenny]

I really just think that's a mindset of "follow the leader." Anti-ship ballistic missiles actually coming anywhere near a target is going to be rare. For anything else, cooperative engagement or just letting the AAW ring do its job is good enough. Sure, there's a risk that any ship could be targeted by a ballistic missile, and the Aegis-equipped defender is going to be too far away to help. But if we wanted absolute proof against that, you would give up on a Navy altogether, because fighting wars is a great way to lose ships. No fight, no losses.

No, that's not how that works.

Ballistics and hypersonics are extremely difficult targets. With SM3s you can hit ballistic missiles in midcourse or high terminal.

But both cases rely on intercepting ships being on a very tight line between launcher and target. Hypersonics require being within about 10km of the target, I'm not sure on just how close you need to be to the ground path for a ballistic target.

I seriously doubt a missile sub is going to launch a coordinated strike that can get past a watchful Burke a kilometer or two away from the targeted frigate. If it spends that much time on a missile salvo (they do still launch a few seconds apart, right?) then won't it be very easily spotted by airborne ASW? And that's assuming the sub got a good track on the target in the first place, which is going to be difficult for a surface ship to do.

At the end of the day, I'm not a submariner, so I will concede if someone has credentials or sources. But none of this passes an intuitive glance.

Who said a Burke is going to be within a kilometer or two? Ships haven't stayed that close together since Korea or Vietnam!

Last time we saw a combat spread for USN ships in satellite, the ships were well over 10km away from each other!

When my sub was playing games with the Lincoln group back in 02, the group was more like 30km between ships.

 

[MadRat]

There must have been a misunderstanding, then. It can take a rocket launch. I thought we were talking about a VGAS-type system for GLSDB, which would impart forces beyond a rocket launch.

If there is confusion its not shared. You are a bit all over the place and not sure what if any point you are trying to stand on. I have demonstrated how it could work, the what, and why.

 

[Cirov]

No, that's not how that works.

Ballistics and hypersonics are extremely difficult targets. With SM3s you can hit ballistic missiles in midcourse or high terminal.

But both cases rely on intercepting ships being on a very tight line between launcher and target. Hypersonics require being within about 10km of the target, I'm not sure on just how close you need to be to the ground path for a ballistic target.



Who said a Burke is going to be within a kilometer or two? Ships haven't stayed that close together since Korea or Vietnam!

Last time we saw a combat spread for USN ships in satellite, the ships were well over 10km away from each other!

When my sub was playing games with the Lincoln group back in 02, the group was more like 30km between ships.

I feel like you're just quibbling for the sake of it. You're right, I was wrong, "a kilometer or two" is a very poor spacing, and it was foolish of me to say that. However, a Burke is also able to intercept missiles from further away than that. The point I sought to make was that a Burke can protect a warship other than itself from conventional antiship missiles--the type an enemy submarine would launch. I was pushing against the idea that an ASW ship without Aegis is a sitting duck for an enemy submarine. If intercepting missiles targeting another warship is completely impossible at realistic spacing, as you seem to be implying, then one really wonders why we space out that much.

Against anti-ship ballistic or hypersonic missiles, which to my knowledge are not likely to be launched by a submarine that is close enough for fleet ASW to be engaging, a Burke is going to have much more trouble defending ships other than itself, I agree. Ballistic and hypersonic missiles are difficult to shoot down. However, I would point out that these missiles are also expensive and difficult to cue onto target, so it will be fairly infrequent that a fleet is even targeted by such systems. When that does occur, I imagine the missiles will go after the biggest, most expensive targets--the carriers, not 4000 ton ASW frigates. Passive defenses (jamming, decoys, plain maneuvering) will reduce the odds of a hit. My big issue is the idea of doubling the cost of an ASW frigate in order to install a fully capable AAW/BMD system, reducing the mission focus on ASW, rather than relying on dedicated AAW/BMD escorts and building more ships to improve resilience against attrition.

So, I just have to ask you to restate your thesis. My thesis is that we CAN have escort warships distinct from other warships, that not EVERY ship in a fleet has to be an equally capable air defender. One ship with Aegis can defend another without. If a sub-hunter is attacked by the missile armament of a sub, the missiles can likely be intercepted by an AAW escort that is part of the same fleet, and leakers can be caught by low-cost point defense like SeaRAM and Phalanx.

I have demonstrated how it could work, the what, and why.

No, buddy, you haven't done that. Here are some of your quotes from the portion of the thread in which you and I have been arguing:

GLSDB and AMRAAM have roughly the same forces on them at launch. Just putting to bed the idea the an SDB cannot take a rocket launch.

This quote seems to indicate you are talking about a pure rocket launch SDB. Which is a strange case to make, for two reasons: one, yeah, of course it can handle a rocket launch, it's been launched out of HIMARS; two, what value is another type of cruise missile? Does GLSDB accomplish something that the current inventory of ship-launched cruise missiles cannot? Is that valuable to the Navy?

I think before people try to sell 16-inch battleship guns here, they may want to read through the VGAS thread: https://www.secretprojects.co.uk/threads/vgas-vertical-gun-for-advanced-ships.38947/

What makes sense may not be such a large conventional gun on a battleship. But if you get a lower pressure gun lobbing 7-8 Stormbreakers per minute downrange to a spot 500 km away then my ears perk up.

This quote is definitively talking about a gun. VGAS is a gun. You're talking about using a gun to boost a rocket launch. This is the position that I have been arguing against for the sum of my time in this thread: a gun-launched cruise missile is going to have to be hardened to take the shock of a gun launch (~20,000 Gs) and therefore won't resemble the payload or cost profile of a cruise missile anymore.

This is a separate argument than the last quote of yours. A 500G rocket launch is literally two orders of magnitude less forceful than a gun launch. Proving one does NOT prove the other. That is why I was confused when you brought up AMRAAM acceleration, because it is completely irrelevant--it's like saying that since I can survive being punched, I can survive being hit by a car.

What I think would be more appropriate than re-birthing giant battleship guns is instead using a recoilless vertical gun, or some 10-inch/255 mm offshoot of something like the Vertical Gun for Advanced Ships (VGAS). This is not meant to fire a flat trajectory, but rather act as a boost-launch to altitude where an attached motor takes it down range prior to release for its final glide. It probably means a minimum range at least beyond 30 or so miles, depending on the slant angle. The 10-inch shells typically carry under 50 pounds of explosives in a 500 pound projectile, so mounting in an SDB 2 payload is a big improvement. It would need some kind of modern sustainer motor, like a ramjet or several akin to what is on the Meteor missile. Your full projectile probably is still around 500 pounds.

This is another quote of yours that makes it clear you are talking about a gun launch, not a rocket launch. So again, it is completely irrelevant that GLSDB can survive the forces of a rocket launch, because a gun launch is that much more powerful. This is true of a recoilless gun as well. Unless, you misused the term "recoilless gun" and meant a pure rocket-propelled projectile. In which case, is this proposition any different from an existing VLS?

Recoilless guns are basically big bazookas. Maybe they could figure out an electromagnetic launcher reaching 680 miles per hour at release. Correct my general math here, but if you could even accelerate an object to 1,000 feet per second (680 mph) in 50 feet it is abput 310 G's. If you lengthen to 100 feet the acceleration is half as many G's. With air resistance that should get someone to 20,000 feet altitude on a slant before losing vertical speed. If you can get a motor going during ascent then by using control surfaces the projectile could bend its path to a level flight without losing all of its initial velocity. The entire flight could be subsonic, and probably stays within GLSDB 2's performance tolerances. The real trick is giving it a way to travel further than a GLSDB by using a pod to carry it downrange before release. And after release you can still travel significantly further with a much smaller RCS and heat signature. Since SDB 2 can survive impacting several feet of concrete, I can only guess it is robust for handling 150 to 300 G launches.

At this point you mention an electromagnetic launcher, which I think is a much better idea but subject to engineering challenges. A magnetic accelerator that moves a 500 pound object to 1,000 feet per second does not, to my knowledge, exist; there are faster accelerators for lighter objects and slower accelerators for heavier objects, though, so it is not an insurmountable problem. I just don't think the engineering problem here can be handwaved casually. I agreed from the beginning that SDB could probably handle accelerations on the order of 300 Gs.

But again, here at the current end of the thread, you definitively close in on "rocket launch" as the point you are arguing. So. Which is it? Rocket launch, conventional/recoilless gun launch, magnetic accelerator launch? These are three different prospects with radically different tactical implications, so I think it is important that you clarify.

If there is confusion its not shared. You are a bit all over the place and not sure what if any point you are trying to stand on.

Allow me to clarify, then, although I think I've been consistent.

I do not believe that gun systems should use rocket-assisted projectiles. Rocket propulsion and gun launch fulfill the same niche and do not complement each other well. A gun is an expensive device to make inexpensive projectiles useful--in a sense, it transfers the cost of an effect from the projectile to the launch system. A rocket launch system is an expensive projectile but an inexpensive launcher, transferring the cost from the launch system in two ways--the rocket tube is cheap, and since missiles are usually very long ranged, the launch platform doesn't have to survive approaching the enemy, and can therefore be cheaper. If you combine the two, you get an expensive gun that fires expensive projectiles, which do not have the range of cruise missiles nor the payload, but are too expensive to be fired at targets without precise designation, such as in the event of active sensor denial. Furthermore, there are cases where precise designation does not improve the effects of a hit (airstrips, large factories, naval bases), and a very precise and expensive system will require the same number of shells as an imprecise and inexpensive system.

I advocate using a very large gun system to transfer even more of the cost from projectiles to a reusable platform. In my opinion, the Navy should produce a 16"-18" gun capable of firing guided, base-bleed subcaliber projectiles to extreme range, or heavier projectiles from a proportionately shorter range, should the situation allow. The guidance package should be simple to cut down costs--this isn't an EW-hardened system that can hit a tank on the first shot, it is just accurate enough to hit within a few hundred meters of the target when fired at extreme (>100km) range. This imprecision is not likely to negatively impact the mission: targets will not be precisely designated since the enemy likely has many forms of sensor denial, and it is likely that the targets will be spread over a large area, anyways. Gas generators for base-bleed are in no way comparable in cost to rocket assistance for gun-fired projectiles, so I imagine the cost per shell will be relatively low. Inaccuracy and low payload relative to a cruise missile should be made up for with volume of fire, which is why the projectile should be cheap and why the warship should mount a large number of guns.

The Navy used to produce 16" and 18" guns, so that engineering problem has already been proven solvable. Building a new one would pose industrial challenges, I fully admit. Guided projectiles are a solved problem, as are base-bleed projectiles. The Army and Navy have both done technical studies on the use of fin-stabilized, saboted, subcaliber projectiles, and found that they are possible and would usefully improve range. At the time of the major study that I read, and the Navy study that I saw referenced, affordable guidance kits were not available; I feel comfortable with the conjecture that this is a significant reason these extended-range projects were not pursued. Therefore, in aggregate, I feel that my proposal uses only proven technology that only requires implementation, rather than any new engineering. New technology, such as an active-cooled 58 caliber 18" gun, could be leveraged for even better results, but is not necessary. We can absolutely discuss probable technologies that only require a little engineering work, like a cruise missile booster that uses a middleweight magnetic accelerator, but it just needs the accompanying disclaimer that we are talking about probable, not definitive, technology.

Does that help? If you reply, I do ask that you be a little more verbose, if you can spare the time. I appreciate reading the full text of an opposing position, sometimes I have trouble inferring context that is not explicitly given.

 

[MadRat]

My hypothesis is that you do not need a 2000 pound 16" gun because it would be an expensive undertaking. We no longer have the manufacturing for that. I am positive they can do it, but what for? Reach targets 100 miles away? These are blunt force trauma in an age where precision and controlled results are the focus. We can already deliver 2000 pound bombs or better via an airplane, which is why these huge weapons went away.

I believe they need the firepower of a gun in a cheaper package that can deliver a steady flow of ordnance out 500 miles. We can currently do it with rocket technology, but these 500 mile range precision rockets are 17 inches in diameter and require quite a lot of volume to store, not to mention each are a few million dollars per launch. if you can bring the cost under half a million and store 3-5 in that same volume and weight, then it would be a better use of the space. Delivery will take a path requiring some form of launch, be it a conventional gun, recoilless gun, electromagnetic accellerator, or a rocket booster. Delivery will take some form of motor to sustain flight post-launch. Glide bombs are a passive way to sustain flight. Air breathing engines are a good way to actively sustain flight. No reason both cannot be used to keep the costs down. To get an SDB out to 500 miles is feasible with a three stage flight: boost to altitude, sustained cruise at altitude, and terminal glide to target. I believe we can do it at or below 500 pounds apiece. I believe the boost to altitude would be the hardest technical hurdle. The sustained cruise at altitude the second hardest technical hurdle. And the terminal glide to target the hurdle largely off the shelf. I believe the first two hurdles can be tackled without over stressing the SDB submunition.

 

[Scott Kenny]

I feel like you're just quibbling for the sake of it. You're right, I was wrong, "a kilometer or two" is a very poor spacing, and it was foolish of me to say that. However, a Burke is also able to intercept missiles from further away than that. The point I sought to make was that a Burke can protect a warship other than itself from conventional antiship missiles--the type an enemy submarine would launch. I was pushing against the idea that an ASW ship without Aegis is a sitting duck for an enemy submarine. If intercepting missiles targeting another warship is completely impossible at realistic spacing, as you seem to be implying, then one really wonders why we space out that much.

A Burke is able to intercept incoming supersonic missiles at much farther distances than ~10km. But the limit for hypersonics and/or ballistics is right around 10km. Hypersonics you need to be within about 10km of target, ballistics you need to be within about 10km of the ground track.

Neither SeaRAM nor CIWS are capable of intercepting hypersonics or ballistics.

The radar horizon for sea skimmers is about 30km, and there are some geometries were you cannot see a sea skimmer until it hits the intervening ship due to that ship's radar shadow.

However.

The only reason there's a Burke on the convoy at all is because we didn't build 30something Zumwalts to replace all the Spruance-class. 1980s escort plans had one Spruance and nine Frigates on each Merchant Convoy, while Underway Replenishment Groups got a Burke and three Frigates. Amphib Groups had two Burkes, a Kidd, and two Frigates. But the Carrier Groups and Battleship Groups got Spruances, not Frigates.

My big issue is the idea of doubling the cost of an ASW frigate in order to install a fully capable AAW/BMD system, reducing the mission focus on ASW, rather than relying on dedicated AAW/BMD escorts and building more ships to improve resilience against attrition.

So, I just have to ask you to restate your thesis. My thesis is that we CAN have escort warships distinct from other warships, that not EVERY ship in a fleet has to be an equally capable air defender. One ship with Aegis can defend another without. If a sub-hunter is attacked by the missile armament of a sub, the missiles can likely be intercepted by an AAW escort that is part of the same fleet, and leakers can be caught by low-cost point defense like SeaRAM and Phalanx.

Constellation's SPY6v3 and ~32x Mk41s (plus 8x Harpoon/NSM cans) is broadly comparable to the Perry-class SPS-49 and Mk13. Top end Air-Search Radar of the time, same as fitted to all non-Aegis ships. Slightly better missile count, since the Perrys didn't have a Sea Sparrow system. Mk13 could hold 40 total missiles, 1 of them a training dummy, and 8x Harpoons in the magazine seems to be standard. So Perry Mk13 held 31s SM1s. A 32cell Mk41 more likely holds ~16x ESSM (4 cells), possibly 6x VL-ASROC, and the rest SM2s and maybe SM6s if you need the performance for hypersonics or ballistics.

Even the Knox-class had the top-end radar of their time (SPS-40, which SPS-49 replaced during the New Threat Upgrade on Tartar ships), and they weren't even guided missile ships!

Also, the Navy has decided that all ships going forward will have SPY6. It saves money on training, it saves money on spare parts, it makes it harder for the enemy to passively ID ships at long range.

 

[CommanderRenHoek]

My theory there is that all of that stuff needs to be done anyway. Can't beat the enemy by needling him from long range. That wins positive kill ratios and loses wars. If we're serious about fighting a war, we're going to need to fight through the enemy's (alleged) A2/AD ring. All the SM-6 and ESSM and AIM-174 and lost planes and ships that we expend getting close enough to shell the enemy will result in killing the enemy, and hopefully make a positive tradeoff on its own. In other words, that's a whole different problem to evaluate.

We could save a LOT more money if we gave up on ESSM and carriers and fighters, and just built LCS to haul very long ranged missiles to a very safe point to lob at the enemy. But since we won't, and we have all these AAW warships full of missiles, carrier based planes, stealth fighters, tankers, bombers, we may as well actually USE them.

I suppose for me, breaking the (presumably PRC) A2/AD bubble is basically the same as winning a conventional war (insofar as that may be possible) if you can already bring and keep the fleet in close through such a massive effort - the details of what exactly the fleet does once its that close is virtually secondary, whether its land bombardment, seizing major features, or just puttering about to exercise sea control. The large gun battleship therefore, to be worthwhile, has to somehow complement and support if not directly contribute to the penetrating fight, not just to be carried into the breach, as it were.

Because the CONOPS currently sounds like asking the US joint force to commit to an inordinate expenditure of A2A/AAW/BMD/ASW weapons (if not platforms and lives) just for the purpose of bringing the adversary's target base under a 100nmi (or so) 18" gun range.

So, I just have to ask you to restate your thesis. My thesis is that we CAN have escort warships distinct from other warships, that not EVERY ship in a fleet has to be an equally capable air defender. One ship with Aegis can defend another without. If a sub-hunter is attacked by the missile armament of a sub, the missiles can likely be intercepted by an AAW escort that is part of the same fleet, and leakers can be caught by low-cost point defense like SeaRAM and Phalanx.

I suppose if we're talking current year, the thing to ask for now is to mass produce LUSVs for ASW to supplement the Burke fleet and future large combatants. At least maybe they might be able to come online in bulk in about two-four years...

ASW's current state-of-the art (this may be a gross simplification, so advance apologies) seems to call for a quiet hull to carry low-frequency active VDS like CAPTAS-4/S2087 to find subs, then to cue engagement with LWTs via shipboard helicopter or a MQ-9 Sea Guardian or VLA-ASROC-alikes for those navies fortunate to still produce those like Japan and ROK. This IMO would benefit far more from CEC/networked engagement and use of simpler force-multipliers such as drone ships and UAVs than the AAW/IAMD/hypersonic defense problem.

Constellation's SPY6v3 and ~32x Mk41s (plus 8x Harpoon/NSM cans) is broadly comparable to the Perry-class SPS-49 and Mk13. Top end Air-Search Radar of the time, same as fitted to all non-Aegis ships. Slightly better missile count, since the Perrys didn't have a Sea Sparrow system. Mk13 could hold 40 total missiles, 1 of them a training dummy, and 8x Harpoons in the magazine seems to be standard. So Perry Mk13 held 31s SM1s. A 32cell Mk41 more likely holds ~16x ESSM (4 cells), possibly 6x VL-ASROC, and the rest SM2s and maybe SM6s if you need the performance for hypersonics or ballistics.

Even the Knox-class had the top-end radar of their time (SPS-40, which SPS-49 replaced during the New Threat Upgrade on Tartar ships), and they weren't even guided missile ships!

Also, the Navy has decided that all ships going forward will have SPY6. It saves money on training, it saves money on spare parts, it makes it harder for the enemy to passively ID ships at long range.

Constellation is IMO far better than Perry, if anything its the spiritual Spruance successor after Zumwalt production got cut and they got rerolled into IRBM-HGV platforms. Had it been seen and sold as such maybe it would not have received so much disinformation and misplaced expectations.

 

[Dilandu]

This quote seems to indicate you are talking about a pure rocket launch SDB. Which is a strange case to make, for two reasons: one, yeah, of course it can handle a rocket launch, it's been launched out of HIMARS; two, what value is another type of cruise missile? Does GLSDB accomplish something that the current inventory of ship-launched cruise missiles cannot? Is that valuable to the Navy?

Well, looking on its size and weight - the GLSDB apparently could be put on ESSM motor and quad-packed into standard Mk-41 cells. It would made its rather efficient weapon for coastal bombardment on tactical distances, shore gunfire support and - last but not least - engagement of drone boats and small crafts.

For clearer picture; if you fill half of Arleigh Burke's Mk-41 cells with quad-packed GLSDB for fire support missions, you would be able to fire 192 highly precision weapons, capable of engaging targets at 150+ km range. I.e. from outside enemy coastal artillery range and beyond the horizon for enemy missiles. And each GLSDB is at least comparable in striking power with heavy artillery shell of the past.

Also important point is that GLSDB is much cheaper than more specialized missiles, and apparently produced in large quantities. I doubt that mating the bomb with another booster for Mk-41 launch would be a big challenge (especially considering that Navy apparently have a lot of rocket motors from old RIM-7, that could be repurposed)

 

[Dilandu]

A Burke is able to intercept incoming supersonic missiles at much farther distances than ~10km. But the limit for hypersonics and/or ballistics is right around 10km. Hypersonics you need to be within about 10km of target, ballistics you need to be within about 10km of the ground track.

Could you elaborate a bit about ballistics and hypersonics? I have some doubts there, but I'm not sure that I'm correct either, so if you could, please explain the interception problem to me.

 

[Scott Kenny]

Could you elaborate a bit about ballistics and hypersonics? I have some doubts there, but I'm not sure that I'm correct either, so if you could, please explain the interception problem to me.

There was a study posted here, said that defense against incoming hypersonics requires the launcher to be within 10km of the target to be able to get the interceptor in front of the hypersonic in time. The engagement envelopes just don't work out any other way. You don't need the sensors that close, just the launchers.

Which for ships means that each ship needs to carry your anti-hypersonics. IIRC that's currently SM6s for the USN, though SM2s may work for lower end hypergliders and high-supersonic missiles. Yes, this means that carriers will need to be refitted to carry Mk41s, or the angled box launcher version, in place of the Mk29 ESSM.

As for ballistics, the height of a target reduces the distance from the ground track that SM3s can be launched from. The Satellite shoot (USA-193, back in 2008) had to happen from one specific spot of ocean and the ship had to be dead vertical when the missile fired. Yes, they were timing the rolls of the ship to decide which of two ships would fire. That was for a target at 250km altitude.

 

[CommanderRenHoek]

Could you elaborate a bit about ballistics and hypersonics? I have some doubts there, but I'm not sure that I'm correct either, so if you could, please explain the interception problem to me.

As I understand it, the basic problem is most tactical/naval in-service interceptor missiles (SM-2, SM-6, Aster, not so sure about the missiles of the S-300+ family) do not have the necessary kinematic performance to be able to conduct wide cross-range intercept of MARVs/HGVs/HACMs at their normal brochure ranges. As Scott mentions, this basically forces the launchers to be either within what is normally considered short-range for air defense if not collocated on the target itself.

This is unsurprising, as with few exceptions almost all extant tactical/naval interceptor missiles were originally designed to engage aircraft and subsonic/supersonic missiles, and their kinematic performance (acceleration and max speed) reflect this.

One might be able to get better cross-range intercept capability if one were firing missiles specifically designed for the job (ala the Glide Phase Intercept program contenders) or if a missile just has monstrous accelerations (ala Sprint or 53T6) but with more range. Such weapons though are likely to be expensive and/or bigger.

 

[Dilandu]

There was a study posted here, said that defense against incoming hypersonics requires the launcher to be within 10km of the target to be able to get the interceptor in front of the hypersonic in time. The engagement envelopes just don't work out any other way. You don't need the sensors that close, just the launchers

Hm. I'm still not sure, why so. If you detected the ballistic/hypersonic far enough, what prevent you from calculating the interception point & shooting missile under command guidance into this point? With the terminal homing switching on later? Of course, cross shots are more complex than head-on interception, but why the range is affected so much? I mean, yes, I understood that hypersonic is flying through your engagement envelope fast, so you have only a limited time to get it. But why can't you just fire missile slightly in advance, to be already in position when hypersonic just reached your envelope?

 

[Scott Kenny]

Hm. I'm still not sure, why so. If you detected the ballistic/hypersonic far enough, what prevent you from calculating the interception point & shooting missile under command guidance into this point? With the terminal homing switching on later? Of course, cross shots are more complex than head-on interception, but why the range is affected so much? I mean, yes, I understood that hypersonic is flying through your engagement envelope fast, so you have only a limited time to get it. But why can't you just fire missile slightly in advance, to be already in position when hypersonic just reached your envelope?

As I understand it, it's a matter of missile acceleration. If you had something like Sprint or HiBEX you have decent cross-target range, but SM2s or Patriots/THAADs really don't have the acceleration to get in front of the hypersonics.

 

[Dilandu]

As I understand it, it's a matter of missile acceleration. If you had something like Sprint or HiBEX you have decent cross-target range, but SM2s or Patriots/THAADs really don't have the acceleration to get in front of the hypersonics.

But it's not so much a matter of acceleration but the matter of detection. If we detected the hypersonic far enough, we could calculate, how much in advance we must shoot the SM-2/PAC-3/THAAD to get to the predicted interception point in time.

 

[Cirov]

But it's not so much a matter of acceleration but the matter of detection. If we detected the hypersonic far enough, we could calculate, how much in advance we must shoot the SM-2/PAC-3/THAAD to get to the predicted interception point in time.

The more predictions and guesswork, the less likely the interception. By and large, you're right, though. My understanding is that the true revolution posed by hypersonics isn't speed, it's maneuverability, so the term we should be using is maneuvering hypersonics. Because yeah, intercepting a missile on a ballistic trajectory is just a math problem, no matter how slow your missile is. But if the enemy missile can tweak its path by a few dozen meters every once in a while, then suddenly you need a very fast and maneuverable missile to catch it.

Full response in the works. Interesting points have been raised.

 

[MadRat]

Intercepting hypersonics can be complicated by vertical launchers requiring the interceptor missile to make its turn while under its most critical acceleration. The articulated rail launchers were an advantage in launching more directly at the target allowing greater energy retention. Maybe the USN should look at bringing some of those twin launchers back to tackle hypersonics. Instead of weighing such recommissioned ships down with every upgraded gizmo, focus on bolting on directed energy weapons, power generation, and datalinks. They just need to be pickets for the highest value assets.

Sea Hunter drones might be a solution, too. If they operated 3-6 of them in a battlegroup that should be sufficient to locate articulating launchers in a strategic formation to intercept such missiles. Their speed would allow the formation to constantly adjust against attacks from both known and expected threat vectors. Of course the Sea Hunters would be dependent on datalinks for targeting incoming bogeys.

https://srmsc.org/images1/7379c.jpgSprint missiles (left launcher in the pic) just had an iconic shape to them. Not sure the public would accept a new line of mini-nukes for a modern version.

 

[Dilandu]

My understanding is that the true revolution posed by hypersonics isn't speed, it's maneuverability, so the term we should be using is maneuvering hypersonics. Because yeah, intercepting a missile on a ballistic trajectory is just a math problem, no matter how slow your missile is. But if the enemy missile can tweak its path by a few dozen meters every once in a while, then suddenly you need a very fast and maneuverable missile to catch it.

Hm, agreed. So it may be more about inability of standard SAM's - not specialized anti-missile missiles - to have enough kinetic energy for rapid maneuvering, required to compensate for hypersonic own maneuvering?

 

[Cirov]

Constellation's SPY6v3 and ~32x Mk41s (plus 8x Harpoon/NSM cans) is broadly comparable to the Perry-class SPS-49 and Mk13. Top end Air-Search Radar of the time, same as fitted to all non-Aegis ships. Slightly better missile count, since the Perrys didn't have a Sea Sparrow system. Mk13 could hold 40 total missiles, 1 of them a training dummy, and 8x Harpoons in the magazine seems to be standard. So Perry Mk13 held 31s SM1s. A 32cell Mk41 more likely holds ~16x ESSM (4 cells), possibly 6x VL-ASROC, and the rest SM2s and maybe SM6s if you need the performance for hypersonics or ballistics.

Surely, the radar isn't the only instrument in determining AAW capability and cost? Perry was never Aegis equipped. I don't think a future ASW FFG should be Aegis equipped either. SPY6 is a building block of a radar, so far as I understand, and two ships can be equipped with SPY6 and have very different costs and capabilities associated with their radar systems.

The primary threat faced by a small, cheap ASW frigate is not going to be hypersonics and ballistics. It will be sub-launched AShMs and torpedoes. So systems like Phalanx and SeaRAM, useless against high-end missiles, will be useful and cheaper than a full BMD capability.

I suppose for me, breaking the (presumably PRC) A2/AD bubble is basically the same as winning a conventional war (insofar as that may be possible) if you can already bring and keep the fleet in close through such a massive effort - the details of what exactly the fleet does once its that close is virtually secondary, whether its land bombardment, seizing major features, or just puttering about to exercise sea control. The large gun battleship therefore, to be worthwhile, has to somehow complement and support if not directly contribute to the penetrating fight, not just to be carried into the breach, as it were.

Because the CONOPS currently sounds like asking the US joint force to commit to an inordinate expenditure of A2A/AAW/BMD/ASW weapons (if not platforms and lives) just for the purpose of bringing the adversary's target base under a 100nmi (or so) 18" gun range.

I strongly disagree with this idea, if I'm reading you right. It sounds like you're claiming a decisive battle; that if the US brings all of its force to try and break through the area-denial zone, China will pitch everything into preventing that breakthrough; and that if the US wins, it doesn't matter what they do on the other side, just that the area-denial zone was broken.

That is just a straight contradiction of the term A2/AD. If the US brings a task force with a heavy concentration of firepower, enough to defend itself and possibly break a determined defense, then the enemy just won't engage. They get to maintain their fleet in being, the collection of assets that forced the US to bring 2+ carriers and 12 Burkes and whatever else to just get past Guam. If they burn it all up in one catastrophic battle, then next time, the US only has to bring 1 carrier, and mission tempo increases.

The point of A2/AD is that the US must move heavily. We can't send two or three ships on a quick jaunt, they'll get swamped and destroyed.

Furthermore, I don't imagine there is any single mission the US could pull off that would win the war. That's the point of using guns, as I see it. Destroying the port at Taichung won't win the war, it'll just complicate enemy supply, and only temporarily before they make slapdash repairs and reroute to improvised floating harbors. If one mission was sufficient, absolutely, use missiles. It won't be.

Lastly, I don't think penetrating to within 150km of a land target will be as difficult as you might imagine. Active sensing will be incredibly dangerous for both sides, everywhere. A maritime patrol plane that burns its surface-search radar can resolve ships at hundred of kilometers, but a lurking enemy fighter with a VLRAAM will detect those radio waves from MUCH further away, and send a missile right back up the beam. Same with any other sort of active sensors. Both sides have stealth aircraft, which make it even more complicated. Passive sensing is safer, but much less useful and it works both ways. A drone with thermal sensors can detect surface warships out to the horizon or maybe a little beyond, but distances are long, so this won't be a cheap Orlan--it needs a range of hundreds of kilometers to even reach past Taiwan, and covering the whole Philippine Sea would require thousands of them. Many thousands, because attrition will be roughly equivalent to Sidewinder production rate, at minimum.

Point being, finding the enemy will not be easy. Both sides are going to have an overlapping zone of sensor denial, hunting each others' drones and anything that radiates, and clearing zones of enemy sensors without giving away the axis along which you're trying to move. The enemy is going to have trouble finding you in time to get in front of you, even if you have to approach very close to their zone.

Well, looking on its size and weight - the GLSDB apparently could be put on ESSM motor and quad-packed into standard Mk-41 cells. It would made its rather efficient weapon for coastal bombardment on tactical distances, shore gunfire support and - last but not least - engagement of drone boats and small crafts.

If quad or just double packed, that sure seems useful. Assuming, of course, a good rate of production. Probably superior to a heavy gun system for prosecuting unprotected, very urgent threats, like a mobile missile or artillery system that UAVs just spotted. Inferior to a gun in the role of area bombardment, which will be more common against a peer threat--if your UAVs are getting chewed up, you can't rely on precision designation required for precision fires, so you have to use imprecise fires and compensate with volume.

There was a study posted here, said that defense against incoming hypersonics requires the launcher to be within 10km of the target to be able to get the interceptor in front of the hypersonic in time. The engagement envelopes just don't work out any other way. You don't need the sensors that close, just the launchers.

I think that is the ideal solution. Every ship should have a few launchers, even ASW-focused ships. Not necessarily VLS, but maybe that's the most efficient option. Concentrate BMD fire control on dedicated BMD/AAW warships, but let them remotely fire a missile off any ship in the task force, just whichever is most advantageously positioned.

 

[Desertfox]

China is putting a lot of effort into specifically finding CVBGs. Two CVBGs and a BBBG will be very hard to hide especially so close to China. And once found China can just swamp defenses with SRBMs, cruise missiles, and drones, without risking any of its fleet or aircraft. You dont even need to sink the carriers, put a hole on the deck and they are done for the rest of the fight. The further out you are from the coast, the less assets China has to shoot back and the harder it is to find you. Getting to 150km means China can start shooting at you from some 3,000km out and keep shooting all the way in.

 

[Colonial-Marine]

I don't think independent BBBGs, like they made centered around the modernized Iowas on occasion, is viable against China. There needs to be airborne early alert and fighters up to have any chance of dealing with whatever Chinese air or missile threats may come their way.

I don't see how the notion of splitting battlegroups into small packets works here. They will eventually be found and defeated in detail.

 

[Scott Kenny]

Surely, the radar isn't the only instrument in determining AAW capability and cost? Perry was never Aegis equipped. I don't think a future ASW FFG should be Aegis equipped either. SPY6 is a building block of a radar, so far as I understand, and two ships can be equipped with SPY6 and have very different costs and capabilities associated with their radar systems.

It's not clear to me how separate the Aegis software is from the SPY1/SPY6 hardware. In any case, you'd still need some kind of fire control system even if you didn't have Aegis installed, and that would cost a lot to develop. Remember that the only currently employed AA missile fire control system in the USN is Aegis!

The primary threat faced by a small, cheap ASW frigate is not going to be hypersonics and ballistics. It will be sub-launched AShMs and torpedoes. So systems like Phalanx and SeaRAM, useless against high-end missiles, will be useful and cheaper than a full BMD capability.

Aegis is not specifically BMD!

Aegis was originally designed as an answer to Soviet bomber regiments armed with 6x AShCMs per plane. It has since been expanded to be capable of BMD, but it's an AA fire control first and foremost.

I think that is the ideal solution. Every ship should have a few launchers, even ASW-focused ships. Not necessarily VLS, but maybe that's the most efficient option. Concentrate BMD fire control on dedicated BMD/AAW warships, but let them remotely fire a missile off any ship in the task force, just whichever is most advantageously positioned.

Thing is, BMD needs big radars. Like 4x 69RMAs, while Burke 3s only have 4x 37. Big radars need a big ship. Crud, even 3x 9 RMAs needed a ship that was 7000 tons, so 4x 69 RMAs is going to have to be huge.

Battleship is going to be a big ship due to other reasons, but because it is a big ship it is ideal to place BMD-sized radar antennas on it.

The other option is to build a 25,000ton+ ship specifically for BMD and nothing else.

Frankly, that gets rejected on cost grounds alone, because you'd need a "BMD battleship" and your "shore bombardment battleship". And that's one BMD Battleship per formation, minimum.

I don't see how the notion of splitting battlegroups into small packets works here. They will eventually be found and defeated in detail.

All the wargames have found that attempting to mass together gets the grouped ships blasted by AShBMs and hypersonics. The ships are going to be operating over 30km apart and so will need to be able to defend themselves against incoming ballistics and hypersonics.

 

[MadRat]

The BBG(X) would be the flagship in the hypothetical BMD role. But if you could disperse some of the exo-interceptors on other ships you lessen the eggs in one basket vulnerability. I'm not so sure your BMD radar has to be 360 degree coverage. Over the East China Sea you have radars from Japan and South Korea. Partial coverage of the South China Sea is provided by Australia's JORN. Horizon increment 3 should help expand surveillance around the Philippines. But there are huge gaps everywhere. The BBG(X) would be required to fill those gaps should a battlegroup move into either sea.

 

[shin_getter]

In the example above, I showed my reasoning to believe that a strike of 1,000 shells could have an effect on target roughly similar to 400 PrSM or TLAM.

Airplanes are just cheaper.

Any mach 2 capable fighter can deliver as much energy as a traditional gun system to a projectile, while having no robustness demands on the projectile. Can add any aerodynamic features or engine at minimum cost to extend range.

Aircraft's basic mode of operation enables vastly superior survivability than ships. What is point blank range for naval warfare is not consistently within weapons range for aircraft.

Air mobility is quite cheap. It is telling that air transport is cheaper than....trains in practice a good fraction of time. Fuel is not that expensive compared to everything else.

If the war being planned is a case of distant power projection where the only aircraft available is from carriers, that is one thing. It is a completely different thing when it is a defensive campaign with land bases available all over the theater.

Guns are simply inferior propulsion than turbojets, and stuff like naval gun fire support need to rest on features like immediate responsiveness and other factors that aircraft may not be suited for.

 

[Dilandu]

Inferior to a gun in the role of area bombardment, which will be more common against a peer threat--if your UAVs are getting chewed up, you can't rely on precision designation required for precision fires, so you have to use imprecise fires and compensate with volume.

For imprecise fire, gun is inferior to multiple rocket launcher.

P.S. Couldn't a version of GLSDB with cluster warhead be made specifically for area bombardment?

 

[Dilandu]

I'm not so sure your BMD radar has to be 360 degree coverage.

On mobile ship? Either that, or it should have the ability to rotate fast enough to compensate for ship maneuvering.

 

[Scott Kenny]

P.S. Couldn't a version of GLSDB with cluster warhead be made specifically for area bombardment?

At that point you should just use the MLRS rocket with the cluster warhead.

 

[Dilandu]

At that point you should just use the MLRS rocket with the cluster warhead.

A point. But MLRS rockets could not glide, and have less range and guidance capability.

 

[MadRat]

GLSDB, remember, is both related to MLRS (M270 and M142) and can glide. It's pretty long which is why I suggested giving it a gun-launch and sustained power from an attached motor prior to bomb release.

Minimal tube-size may be closer to a 12 inch diameter than the 11 inches I had guessed. But with a weight of around 500 pounds I figured it should be possible taking it up to a cruise altitude greater than 25,000 feet mostly on gun power with around a 310 G acceleration target to reach the 1000 feet per second launch speed. GLSDB appears to be closer to 500 G acceleration on a short burning booster and has demonstrated a post-glide range to 79 miles. With a low-cost sustainer motor I would hope range could more than double. In the case of a modern BB it should outrange most missile threats it may encounter.

 

[Scott Kenny]

GLSDB, remember, is both related to MLRS (M270 and M142) and can glide. It's pretty long which is why I suggested giving it a gun-launch and sustained power from an attached motor prior to bomb release.

Minimal tube-size may be closer to a 12 inch diameter than the 11 inches I had guessed. But with a weight of around 500 pounds I figured it should be possible taking it up to a cruise altitude greater than 25,000 feet mostly on gun power with around a 310 G acceleration target to reach the 1000 feet per second launch speed. GLSDB appears to be closer to 500 G acceleration on a short burning booster and has demonstrated a post-glide range to 79 miles. With a low-cost sustainer motor I would hope range could more than double. In the case of a modern BB it should outrange most missile threats it may encounter.

The difference is that a battleship gun is more like 50,000 G acceleration. So you'd have to completely redesign SDBs to survive that launch force.

Now, I did have an idea with a larger-diameter rocket booster and a strongback/sabot that mounted to the bomb shackles

 

[MadRat]

The difference is that a battleship gun is more like 50,000 G acceleration. So you'd have to completely redesign SDBs to survive that launch force.

Now, I did have an idea with a larger-diameter rocket booster and a strongback/sabot that mounted to the bomb shackles

2500 feet per second in about 66 feet of barrel length doesn't sound anywhere close to 50,000 G acceleration. That is below 1,500 G acceleration.

 

[Scott Kenny]

Crap, I think I forgot to convert from f/s/s to gees.

Not sure an SDB can survive 1500 gees (1480 if we want to be picky), but that's a lot easier ask than what I thought it woud be.