I don't know which version of Springsharp you have, but Springsharp 3 allows you to input miscellaneous weights anywhere in the ship (hull, above or below water, on deck, above deck, in the voids), which is useful for simulating radars and communications equipment. I would simulate missiles as small turret on barbette mounts and use the barbette armor to simulate the weight of the missiles and launch cells. Dealing with this kind of stuff is definitely more difficult that using Springsharp for the pre-WWI warships its algorithms were designed to simulate, but Springsharp is ultimately just a metal-hulled warship weight distribution simulator, so it can be made to work.
US Navy Strike Cruiser timeline
- Thread starter BillKerman1234
- Start date
Okay, I've added a few more things to the spreadsheet, and now I'm sure I'm not doing something right. The ships have way too much weight left over, even when accounting for the mass of the VLS and Aegis.
That's what the 'payload mass' listed is - I inputted the dimensions of the ships and then added misc weight until the hull strength reached 1.
Huh, I just realized something. You said modern ships were volume-dependent, not displacement-dependent right? Could it be that a Flight II Arleigh Burke actually has 2,500 tonnes of extra mass capability that it simply doesn't use because there is no need to / no place to put anything? Perhaps the entire ship is already taken up by hallways, machinery spaces, living quarters, etc and even if they have weight leftover they cant properly utilize it. Could the 1,260 tonnes figure on the CGBL study not be the amount of extra stuff that can be added to the hull, but rather how much heavier the hull needs to be in order to be enlarged and make room for that potential extra stuff?
For now, I'm going to be assuming that this assumption is correct. It does have some very interesting implications though. I'm going to have to continue researching this.
For now, I'm going to be assuming that this assumption is correct. It does have some very interesting implications though. I'm going to have to continue researching this.
And this is now the third post in a row from me, but I've had another thought. Those ships have a bunch of extra mass capability that they can't use because they don't have the volume, right? Well, armor doesn't take up much volume. And I know what you're going to say - and I agree. In the cold war, armor is useless. But maybe not post-cold war.
Think about it, armor doesn't make it harder to mission kill a ship, yes, but it does make it harder to sink a ship. During the cold war, that didn't matter, why bother trying to make a mission killed ship survivable if there wouldn't be any friendly ports left to sail to in a nuclear apocalypse anyway? But post-cold war, the USN is going to be facing enemies that don't work like that. Outside of China, most of the enemies that the USN would be facing use much smaller AShMs, which can be effectively armored against. Not to maintain improvised explosives and such - look at the USS Cole. That was 320 to 400 kg of explosives places just outside the hull - I'd have to do the math of course, but I'm pretty sure that such an explosion would not have been as dangerous if the ship was armored.
Also, keep in mind I'm not proposing adding huge amounts of armor here, 2 to 4 inches should be fine. That means weight shouldn't be an issue, especially considering the extra mass these ships can supposedly take. The bigger problem would be cost, and the increased strain on the engines. The latter I can calculate with springsharp, the former I have no idea where to look for. Any suggestions?
EDIT: Come to think of it, even if this proves workable it's possible that it would simply be too much of a change in thinking for the USN for them to actually adopt just from butterflies. Oh well, it still interesting to think about.
Think about it, armor doesn't make it harder to mission kill a ship, yes, but it does make it harder to sink a ship. During the cold war, that didn't matter, why bother trying to make a mission killed ship survivable if there wouldn't be any friendly ports left to sail to in a nuclear apocalypse anyway? But post-cold war, the USN is going to be facing enemies that don't work like that. Outside of China, most of the enemies that the USN would be facing use much smaller AShMs, which can be effectively armored against. Not to maintain improvised explosives and such - look at the USS Cole. That was 320 to 400 kg of explosives places just outside the hull - I'd have to do the math of course, but I'm pretty sure that such an explosion would not have been as dangerous if the ship was armored.
Also, keep in mind I'm not proposing adding huge amounts of armor here, 2 to 4 inches should be fine. That means weight shouldn't be an issue, especially considering the extra mass these ships can supposedly take. The bigger problem would be cost, and the increased strain on the engines. The latter I can calculate with springsharp, the former I have no idea where to look for. Any suggestions?
EDIT: Come to think of it, even if this proves workable it's possible that it would simply be too much of a change in thinking for the USN for them to actually adopt just from butterflies. Oh well, it still interesting to think about.
Model a 300 KG Torpex torpedo explosion a few feet below the waterline --
That will mission kill an unarmored ship. That will mission kill an armored ship.
As a reminder, armor is heavy, armor is expensive compared to structural steel, and armor makes maintenance a gold plated problem. Armor also can not protect the fighting components of the ship (radar, antennas etc)
What capability are you trying to buy with armor that can not be bought with good subdivision, spall/shrapnel Kevlar liners, good damage control and good operational procedures? And what are you willing to trade-off as armor is going to throw the weight balance of the ship that is designed to be lightly to completely un-armored way off.
2-4 inches isn't going to do squat against 320-400 kilograms of explosives detonating against the hull. 4 inches is and was only sufficient against relatively small high-explosive payloads, such as 6" shells with only 13 lbs of picric acid-based explosive.
And as I explained the last time you brought this up, you can't armor the radar systems. That renders armor fairly pointless.
In any case modern surface combatants do have splinter armor in key areas. That's all that's really worthwhile.
1000 times this. To protect against modern missile warheads, HEAT shells or rocket assisted AP rounds, you need, at minimum, battleship levels of armor. That means 12+ inches and probably closer to 15+ to be truly effective. That's just not practical. And, as you point out, that ignores the fact far the important bits can't be armored.
Good points, although I explicitly said that this wasn't about making a ship harder to mission kill. Doing that with armor is impossible. I was talking about increasing crew survivability against asymmetrical threats (RPGs, anti-tank rockets, etc). The point about armor being heavy doesn't matter unless the ship weighs less than 8,000 tonnes, any modern USN ship bigger than that has weight margins for days (the CGBL has 3,000+ tonnes of extra weight margin by my latest estimation, although I will have to recheck that after adding the armor in springsharp to be sure). With all that being said, armor is still very expensive, as you pointed out. Does anyone know how much a 140 meter x 8 meter x 100 mm sheet of hardened armor costs? I'd like to do the math on this and see if it's worthwhile.
What I guess I'm trying to say is that it's possible that a USN ship designed specifically for fighting asymmetrical threats in the littorals, displacing more than 8,000 tonnes could benefit from having armor to protect from tanks/portable artillery/guys with RPGs seeking up on it. Because at the end of the day, while CIWS is good, I have doubts about it being able to shoot down tank shells or ATMs.
EDIT: Just to be clear, I'm not trying to restart my previous thread about armored warships. That one was mainly about protecting from full-scale AShMs. This is specifically about protecting from asymmetrical threats, most of which are land-based and can launch on the ship too close for it to respond with active defenses.
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If you're putting several hundred to a thousand tons of armor on a ship because the threat model is RPGs, 20mm cannon and perhaps TOW missiles, you're doing things wrong.
If that is the threat model, double space the hull and compartmentalize the gap in between the outer and inner hulls aggressively and then spall line critical compartments and passages with Kevlar.
If you are worried about direct fire from a T-72 aboard an Aegis destroyer, you're fighting wrong.
Beyond splinter protection, armor is about making a ship harder to mission kill. Period. Full stop.
And in any case you're not going to be able to fit enough armor to stop RPGs and anti-tank rockets. The venerable, 1950s-era RPG-7 can penetrate 12 to 23 inches of steel armor, depending on the warhead, let alone anything heavier or more advanced. Not for nothing have the South Koreans, who have the most littoral combat experience of any Western-oriented navy, focused on range, sensors, and firepower over slapping armor on their littoral combatants.
Okay, so no armor. Got it.
Next thing to consider: speed. According to springsharp, an Arleigh Burke Flight I destroyer with 100,000 hp could reach 35.3 knots. This seems dubious, but I have no evidence really not to trust it. Thoughts?
Well, splinter protection only, more like. But nothing heavier.
Springsharp can be weird about high speeds, so I wouldn't trust it. It wouldn't be totally surprising to find the Burkes are faster than their listed speed of 32 knots, but 35 is pushing it. I really wish there were available speed figures for the old DLGs, that would be a good point of comparison.
But in any case, you really only need a top speed of 30 knots in a carrier escort and everything past that is gravy.
And they only need that kind of speed for brief stretches while the carrier is doing fight ops.
Okay, I'll say 32.5 to be on the safe side (mostly because I already calculated them at that speed and I don't want to redo all of that). That was how fast the Spruances could go, so there's precedence.
Here's what I have so far:
Top to bottom:
Johnston Flight I - this is basically an OTL Arleigh Burke. The waterline length is slightly different I think, but only by a few cm.
Johnston Flight II - This one is based on the 1989 FIII proposal, but with the front half of an OTL FII. Basically, it's a Johnston Flight I with a slight length extension, the rear deck cutout filled in, the VLS moved back, and a helicopter hangar added.
Johnston Flight III - This is basically the OTL 1989 FIII but better. Relative to the Johnston FII, the hangar has been expanded (and since there's no VLS is the way it can hold 3 helicopters), the Harpoon launchers have been moved forwards to clear the CIWSs rear fire arc, and the bow has been lengthened to fit a 64-cell VLS module.
Johnston Flight IV - This one is a so-called 'Guided-missile frigate leader', and was built to lead squadrons of LCS/FFXs into engagements. The rear VLS has been deleted and the hangar extended backward to the stern, with the landing deck atop it and two lifts to access the hangar (which can hold 4 to 8 helicopters depending on what type they are). The forward VLS has been reduced in size since they really don't need 64 cells, and that lets her fit a Mk. 71 8" gun from the Spruances that I just realized I forgot to draw properly.
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LCS has no VLS capability, and adding it to all of them would be too expensive. It makes for sense to have one VLS ship to cover an entire squadron of them with ESSMs (48 cells quadpacked is more than enough). The F-IV Johnston has a much lower draft (6 meters, like the Sejong the Great) to operate in the Littorals, and the huge hangar/flight deck is to operate attack helicopters to provide aerial support. The Mk 71 gun is for Naval gunfire, since they will be operating in the Littorals against both sea and ground targets at fairly close ranges.
That’s if they go with the OTL LCS, of course. If they go with a larger design ITTL then the Flight IV Johnstons probably won’t be built.
Yeah, this seems like a bad idea all around. Big ships aren't great in littorals and the minute the littoral mission evaporates this runs into the same sort of problems the OTL Zumwalts did of being too specialized in that role.
I'm not anywhere even close to an expert in naval warfare, but if they need that level of helicopter support, why would they just send in an Amphibious Expeditionary Group with an LHA or LHD with Harriers or Lightnings and a lot more helicopters? And more powerful escorts.
RamscoopRaider
Donor
So don't add VLS to all of them, add it to some of them, advantage of a modular ship, you can add things easier, and one ship in a 4 ship squadron is likely enough. The LCS already can carry 2 helos each and have pretty big flight decks, a 4 ship squadron would thus have 8 helos, what situations are 8 not enough but 12-16 would be?
An issue with this is that a 6m draft ship constrains the operations of 4m draft ships, so the LCS would have less space to operate
As mentioned the ship is also too specialized, you are paying as much as a full DDG for what amounts to a single mission vessel
It‘s not as specialised as you think it is. Sure, she was designed to support LCSs, but she is blue-water capable, and with that many helicopters would be a very formidable ASW escort ship. Still, the points about LCS being modular (again, if the OTL version gets built) are valid. So I’ll drop the Johnston F-IV. Next thing I’ll work on will be the CGBL (finally!).