One of the common rejoinders employed by battleship critics is that modern anti-ship missiles would quickly and easily sink a battleship. Of course, this statement is made with zero supporting evidence. On the contrary, there is much evidence that suggests – but does not explicitly prove – that battleships would be largely immune to anti-ship missiles.
Battleship critics have suggested two modes of ‘killing’ a battleship:
- Outright sinking using modern anti-ship cruise missiles
- Mission killing due to destruction of top side electronics, sensors, and weapons
We’ll examine each of those modes but, first, let’s understand some underlying concepts.
Relevant Concepts
Armor Piercing Shells – A battleship’s main weapon was the 16”+ gun firing 2500 lb armor piercing (AP) or high explosive (HE/HC) shells travelling at velocities of Mach 2+. For example, the Iowa’s 16” AP/Mk8 weighed 2700 lb and had a muzzle velocity of 2425 ft/sec (1653 mph, Mach 2.1).
What is an armor piercing (AP) shell?
U.S. Navy World War II nomenclature uses the words "Armor Piercing" (AP) to mean that the base-fuzed, hard-nosed projectile so labeled has a thick, steel AP cap designed to allow intact penetration through some thickness of Class "A" (face-hardened) armor plate.[1]
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| AP Shell Mk 8 |
Armor piercing shells were designed, as the name implies, to penetrate a ship’s armor. This was accomplished by placing a heavy, solid metal cap over the explosive shell. Grossly simplifying, the cap was a sacrificial ‘point’ that would penetrate the armor allowing the explosive shell behind it to enter the ship intact and functional before exploding.
Armor – A battleship’s armor (we’re talking about US battleships in this post) is intended to protect vital equipment. Any equipment not protected is not vital – useful, undoubtedly, but not vital. As a general statement, battleship armor was designed to provide immunity to another battleship’s weapons which means 16”+ shells. It is noteworthy that the Iowa class was designed to be immune to 16” plunging fire.
Armor was not, as so many people believe, simply thick plates of steel attached to the sides of the ship. Instead, it was a sophisticated system of plates, layers, carefully calculated void spaces, differing materials and treatments of steel, calculated angles (obliquity), etc. all working together to defeat attacking shells.
The main mechanism of armor protection was the act of decapping incoming AP shells before they could penetrate the armor. In other words, the armor was designed to strip the armor piercing cap off the incoming shell before penetration could occur. If the shell could be decapped, the shell’s penetration would be prevented or severely limited. Navweaps website has articles by Nathan Okun that go into much greater detail, for those interested.[1,2]
Armor penetration requires a rather lot of information, but decapping of the projectile by breaking the rather weak solder and/or mechanical bond between the nose and cap base is very, very simple:
0.08-0.08049-caliber thickness of any kind of homogeneous iron or steel plate has a 50% chance of decapping any kind of capped projectile over 40mm in diameter under ANY impact condition, penetrating or not.
0.0805-caliber and up thickness always decaps the projectile, penetrating or not.[2]
The USN Iowa and South Dakota class battleships have an internal inclined main armor belt. What isn't well known is that they also have a shell plating outside of this belt that acts as a decapping plate. On the South Dakota's, this shell plating is 1.25" thick (3.2 cm) and on the Iowa's it is 1.5" thick (3.81 cm). Using Nathan's formula above, the South Dakota's plating would be sufficient to decap any projectile up to 15.5" (39.4 cm) and the Iowa's plating would be sufficient to decap any projectile up to 18.6" (47.3 cm). This would imply that the Japanese Type 91 18.1" (46 cm) APC projectiles fired by the Yamato would be decapped by the Iowa's shell plating before they reached the main armor belt. Decapping an AP projectile greatly decreases their armor-penetration ability against face-hardened naval armor (unprotected projectile nose now shatters into pieces) at under 45° impact obliquity angle.[2]
The angle of impact (obliquity) of a shell on armor was also immensely important. A perfectly perpendicular strike on armor was the most difficult to defeat while angled impacts acted to disperse the force parallel to the armor, causing a ricochet or greatly reduced damage. This is why armor was angled when possible and where appropriate. Again, I’m grossly simplifying the physics and mechanics of this.
Another important factor that most people are unaware of is just how extensive the armor coverage was. For example, the conning tower of the ship was heavily armored as opposed to today’s ships whose bridge superstructures are not armored at all and consist of what amounts to thin aluminum foil, for all practical combat purposes. Note the thickness (17.3”) of armor around the conning tower of the New Jersey in the photo below.
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| Armored Conning Tower |
Critics who think a battleship’s topside would be destroyed by missiles are unaware of the extent of armor. WWII ships were built with armored structures and equipment that we don’t even consider for armor today. The topsides, while not protected as heavily as the hull, were still heavily armored.
One of the common misguided notions is that anti-ship missiles will conduct pop-up attacks and strike the vulnerable decks from above where the battleship is helpless. Battleships were design to defeat plunging fire. From Wikipedia,
The deck armor consists of a 1.5-inch-thick (38 mm) STS weather deck, a combined 6-inch-thick (152 mm) Class B and STS main armor deck, and a 0.63-inch-thick (16 mm) STS splinter deck. Over the magazines, the splinter deck is replaced by a 1-inch (25 mm) STS third deck that separates the magazine from the main armored deck.[3]
Thus, overhead strikes were well accounted for with the upper deck providing the decapping function and the underlying deck providing the main resistance against whatever penetration did occur. Of course, if it were established that overhead attacks were a common staple of missile attacks, a modern version of a battleship could easily redesign the armor to beef up that area.
Anti-Ship Missiles - Now that we understand what is required to have a chance of penetrating battleship armor (meaning an AP shell) and how the armor acts to protect the ship, let’s look at the modern ‘shell’ which is, of course, the anti-ship missile (ASM). ASMs can be crudely grouped into two categories:
Light – typified by the Harpoon (1500 lbs, 490 lb warhead), Exocet (1700 lbs, 360 lb warhead), and C-80x family (418 lb warhead), among others. These are relatively small, light, generally subsonic, and have warheads in the few hundred pound range.
Heavy – typified by the BrahMos (6600 lb, 660 lb warhead), P-700 Granit (15,400 lb, 1650 lb warhead), and P-800 Oniks (6600 lb, 660 lb warhead). These missiles are relatively large, heavy, generally supersonic, and have warheads in the 600-1000+ lb range. Some of these missiles are described as semi-armor piercing, whatever that means.
Shell-Missile Comparison
The obvious next step is to understand how shells and missiles compare as far as their ability to penetrate battleship armor.
Skin – A key characteristic of shells and missiles is the thickness of their ‘skins’. A missile, even the largest, has relatively very thin skin amounting to no more than that necessary to hold the internal components in place and provide an aerodynamic shape. In contrast, naval shells have very thick walls which both aid in penetration and serve to contain and compress the explosive chemical reaction (the blast).
Penetration – The common, light ASMs are not generally claimed to be armor
piercing and are, conceptually, simply explosives and motors contained in a
very thin skin of aerodynamically shaped sheet metal. They have no armor piercing capability
whatsoever beyond their inherent kinetic energy which is woefully insufficient
to penetrate significant armor. The
armor would not even need to perform its de-capping function since the missiles
have no armor piercing cap. The missile
would simply explode against the outside of the armor, doing little more than
scratching the paint.
Several decades ago, I read reports of tests by the Navy involving launches of anti-ship missiles against armor plates. Unfortunately, at the time, I did not save the reports and have been unable to find them now. As I recall, the missile was the Harpoon. I do not recall the armor plate thickness or composition. Regardless, the result was that the missile achieved no penetration and did no damage.
As noted, some missiles claim to be ‘semi-armor piercing’ but I’ve seen no description or definition of what that means. Presumably, it means it might be able to penetrate some small degree of armor but, unless the missile contains true armor piercing caps equivalent to 16” battleship shells and the rest of the missile body is encased in a thick shell, the missile will have no chance of penetrating any significant degree of armor.
Few – I actually don’t know of any – anti-ship missiles have actual AP noses. Battleship armor is designed to decap heavy, large caliber shells so, logically, an AP missile, if such existed, would also be decapped and prevented from penetrating.
I am unaware of any credible testing of anti-ship missiles against armor. There have been Russian claims but they are unverifiable and Russian claims are almost invariably greatly exaggerated, as the Russian performance in Ukraine has demonstrated.
Discussion
We noted that battleship critics claim two modes of ‘destruction’ of battleships: Let’s consider the two modes.
Sinking – In order to achieve a sinking, an ASM would have to penetrate multiple layers of armor to reach vital internal areas. Even then, that would not open holes for water ingress. Fire, of course, is always a threat to ships but with vital equipment protected, armor abounding, and extensive compartmentation, it would be very difficult to achieve a sinking.
Mission Kill – As noted, topside equipment is subject to damage but nothing topside is vital. Battleships were designed with armored sensors and had multiple redundant and backup systems so significant impairment of a battleship’s function via topside damage would be extremely difficult to achieve. A modern version of a battleship would have its various radar, electro-optical, infrared, and electronic warfare sensors housed in armored structures as the WWII battleships did with their various radar, fire control, and optical sensors.
A modern version would have many isolated self-defense weapons (SeaRAM, CIWS) each of which has its own self-contained radar. A single hit could not damage much of a ship's defensive weapons. Besides, defense is what escorts are for. Citing the fact that a battleship was sunk somewhere in history does not invalidate the power and survivability of the type.
No ship is invulnerable but a battleship is the least vulnerable ship ever built. A battleship group with Aegis escorts would be an exceedingly difficult group to defeat.
Some might say that this entire discussion is pointless because we are never going to bring battleships back. Well, that may or may not be true but there is a larger point to this and that is the role and value of armor. Whether that armor is applied to a true battleship or to some other type of ship, this discussion reminds us that armor serves an invaluable purpose and should be part of every warship design.
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[1]NavWeaps website, “Decapping Revisited”, Nathan Okun,
http://www.navweaps.com/index_tech/tech-085.php
[2]NavWeaps website, “The Armor Thickness Necessary to Decap an APC Projectile”, Nathan Okun,
http://www.navweaps.com/index_tech/tech-045.php
[3]https://en.wikipedia.org/wiki/Iowa-class_battleship#Armor
Long time reader, first time commenter. Some thoughts on your post: A couple of concepts seem (to me) to be true regarding armor and the weapons it is designed to defeat.
ReplyDelete(in a few parts). Part 1: First, as you know, there is a constant evolutionary battle between attack and defence. We saw that in the 'classic age' of battleships with the increasing power of projectiles (gunpowder vs cordite for higher muzzle velocities, TNT vs gunpowder for bursting charge effects, larger and larger main gun diameters (12in, 13.5in, 14in, 15in, 16in, 18in) and never larger gun calibers, more sophisticated shell designs, etc. And of course, armor and armor schemes advanced as well (wood, iron, steel, cemented armor, Krupp armor, etc.). I think you have covered these points well in the past. You have also covered the fact that you can't hit a target if you can't see it (sensors) or have the means to adjust your fire control parameters fast enough to hit it (ranging, ballistics, semi-homing and homing weapon systems etc.) -- and of course this is where smoke, passive, and active counter-measures come in on defense. The one aspect that I don't think has been discussed is 'shot placement' and how that might upset the balance between attack and defense.
Part 2: Legends of Robin Hood and William Tell aside, ranged weaponry has always been a bit of a 'hit or miss' affair (pun intended). The many variables of 'shooting' are hard to overcome (consistent bow tension and release, wind, target movement, target armor placement (e.g. a shield), etc.), and technologically, as these constrains become manageable, inevitably effective shot range increases to the point of 'semi-un-manageable' once again (knowledge of ballistics, computers, laser-range finders, etc increase consistency and placement at certain ranges, but effectively push the effective range envelope out further and further).
ReplyDeleteI think that armor's effectiveness may depend on this 'shot placement' uncertainty, especially in the context of true 'battleships' of the 20th century. Until about 1945, hitting a battleship (with another battleship) was still an uncertain matter (looking at Dogger Bank, Jutland, North Cape, Denmark Strait, etc.) --- clearly less than 20% of the shells fired hit and pretty much all of those hits were 'randomly placed' -- they may have hit armor (or not), they may have penetrated (or not), they may have hit something vital or mission critical (or not). In 1945, at Leyte Gulf, the range was relatively short and the radar (ballistics) good enough to make really effect fires a reality --- but even then, the targeting of the Japanese ships was 'general' (i.e. 'just hit it'), not particular ('aim for the turrets or just the bridge).
So, what's my point? My point is that micro-targeting may make a big enough difference to change the armor / armor penetration issue (just a proposal for consideration). Weapon systems (guided bombs and shells) have (under the right conditions with regard to electronic environment and anti-air systems) the ability to target very precise areas of a ship at very long distances. And while I don't doubt modern armor's (and counter-measure's) to 'stand up to' such an attack (assuming it is designed and built well, kept operational and actually employed!), I think the chancing of avoiding an unarmored 'mission kill' shot might be just too low to make it worth while (or at least that should be a consideration).
Part 3: The point of a battleship of old was to be strong enough (where it mattered) to take a few hits and keep slugging and to hopefully hit the opponent harder and faster than you yourself take punishment. Hits in the non-protected areas of the big ship were likely (but not certainly) to be non-critical (Bismark's and Warspite Jutland rudder hits the unwanted exception to this rule). The problem now-a-days may be that non-protected hits may not be random anymore, and just too hard to protect from every possibility. Warspite (pretty well armoured although no longer best in class at the time) was holed by a smart bomb down its funnel in 1944 (I believe). Now, that particular hit was probably chance, but the chances of such hits not being by chance in the future are much much higher. I don't think Iowa would have been safe from that hit, and even if it were, that smart, independently manoeuvrable projectile and targeting knowledge would just find some other way. I think that the thought that such 'directed hits' might be possible in the future is something that discouraged armor thenceforth (along with other factors). The end result of directed weapon hits is that the 'battleship' just can't 'stay in there' and 'slug it out' --- mainly because the attack is asymmetric (the ship is attacked maybe by surprise and without the ability to respond in kind at that moment, hence no 'slugging') and very debilitating (if successful) because it becomes a mission-kill (or worse). Perhaps it then becomes a game of 'hitting eggshells with hammers' where 'he who hits first wins' and 'he who is hit, it out of the game'. That is how it is in modern tank vs tank warfare. I can see where armor and redundancies etc may keep the ship afloat (and the crew alive) for another day, but maybe with autonomous and self-directed arrows we have reached a temporary technological plateau in the armor / penetration dynamic we have not had to deal with in the past.
ReplyDeleteWelcome! Your comment(s) is interesting and, if I understand you correctly and can summarize, you're suggesting that modern missiles can 'outsmart' armor by being able to select pinpoint, unprotected, attack spots on the target ship.
DeleteWhile there are missiles that claim to be able to target a specific area of a ship, I've yet to hear any claim that a missile has the specificity to choose a specific bridge window or fly down an exhaust stack like Luke Skywalker defeating the Death Star. So, missiles are, at best, limited to a general area like 'midships' or 'superstructure'.
Moving on from missile claims, every SINKEX video I've seen shows what appears to be randomly place hits. There may be a video of a very precisely placed exercise hit (assuming it wasn't a random occurrence that just looked to be precise) but I haven't seen one.
I have no doubt that under perfectly controlled conditions a missile designed for pinpoint target placement could, in a test fire, achieve the desired result. However, combat is not a perfectly controlled scenario. In combat, the missile will approach from a sub-optimum direction and height, the ship will be moving (they never do in SINKEX's), obscurants will be used (smoke and multi-spectral gas), defensive weapons will be firing, decoys will be in effect, electronic warfare countermeasures will be active, weather may be rainy, foggy, high waves, strong wind, and so on. The likelihood of achieving pinpoint attack placement seems very poor.
Finally, if that kind of pinpoint attack placement becomes routine, the pendulum will again swing and the vulnerable attack locations will be armored, hidden, protected by clusters of point defense weapons, and so on.
In summary, your point is very interesting but,
1. I see no evidence (beyond manufacturer claims which are always exaggerated) that missiles are capable of achieving the degree of specificity that you're discussing.
2. The advantage of such a missile would be short-lived as the back-and-forth developmental balance that you discussed would quickly shift in the other direction by employing easily anticipated and implemented counters.
All that said, your comment is an excellent contribution to the discussion. What do you think of my response? Does it change your thoughts any? I'm not attempting to prove or win anything, just offering the other side of the thinking for your consideration.
Again, welcome, and an excellent first contribution!
@Anonymous
DeleteIf missiles have that kind of pinpoint accuracy, and I'm not sold on that, then any unarmoured ship is a two-hit sink at best.
Part 1: I think your response (and Lonfo's) are great and certainly true (from 1945 until today). And maybe into the future as well (although this is where the 'what if' nature of my comment comes in). I think it is reasonably clear that a modern strike fighter or bomber , with laser (or other) guided weapons could relatively easily disable a 1940's battleship: it can deliver a penetrating payload against lightly to moderately armoured sections (or a non-penetrating but more destructive payload against unarmored sections) while being immune to the ships defensive systems or manuevers. What saves that ship (or today's ships) in reality is that early warning systems, anti-air and anti-missiles systems, electronic and other countermeasures etc make the plane's survival questionable and hence the standoff distance sufficient to prevent a guaranteed hit (let alone a precisely targeted hit).
DeletePart 2: As a thought experiment, think of a Falklands scenario with say even 2003 level precision attacks. It would be very ugly for the surface forces in that context (but fortunately for the British, the attack and defense technologies were still roughly in balance). But what if there is a temporary, but long enough, time period where 'strike' (in all its forms -- air, undersea, etc) because significantly 'smarter' or 'faster' or more 'persistent' than the defense. It could be very ugly for those on the receiving end (as an aside, that appears at the moment to be the case with the drone ground war in Ukraine -- the systems, sensors, countermeasures etc are different than naval warfare, but the concept that those on the ground get hit (without even knowing that they are targeted and without a decent means of countering the attack) applies. In some ways, it can appear that ship development in the 1970's until today has had this fear in mine -- hence the emphasis on sensors, countermeasures, etc over offensive firepower (at least in part).
DeletePart 3: At this moment in time, I don't think that it is the precision of the weapon that is the limiting factor (even if existing naval weapon systems don't have that capability). The limiting factor is probably target detection and acquisition, time to target, and delivery platform availability, responsiveness, and survivability. Those latter factors may be very hard to overcome, even with autonomous weapons of the future, but there will still be choke points, harbours, etc where asymmetric, precise attack may become just too short notice, overwhelming, or persistent. Having multi-purpose ships makes this situation even worse. In some ways, I think this line of thinking makes your ideas of single function, armoured & survivable, plentiful manned ships even more of a priority. The current line of naval evolution (very expensive, do everything ships designed not to take but to ward off blows may be doomed if the blows cannot be deterred, sufficiently destroyed, and stopped before they get to you).
DeletePart 4: One last thought, about battleships in particular. Armour really does seem to make sense for most warships-- the alternative is disposable ships, but for crewed ships at least it would seem that physical protection, redundancy, passive boyancy seems reasonable. But battleships per se? I think it depends on the mission. Initially, battleships were the long range strike weapon of the day. Then they became the king of the off-shore bombardment. But there are other ways to achieve these goals, so I am not sure of their need (although I love the romance of the idea). Having viable projectile weapons is the not the issue -- I think you've made good points about that over the years, but battleships as we have historically understood them? Not sure.
Delete"a modern strike fighter or bomber , with laser (or other) guided weapons"
DeleteIt is almost inconceivable that an aircraft, carrying the type of precision laser guided weapon you're envisioning, could survive to penetrate a battleship's escort protection and then hang around, leisurely directing a targeting laser while it, or another aircraft, releases the actual bomb. Hanging around over a modern naval vessel is instant suicide. Remember, the kind of laser guided bomb you seem to be envisioning is a very short range weapon.
There are missiles that claim to be able to use optical guidance to compare the sight picture to an image library and pick out a precise attack point but I have grave doubts about the ability to actually do that in combat, as I described in a previous comment.
Now, if we 'parked' a battleship somewhere and allowed the enemy to send wave after wave of aircraft with precision guided weapons then, sure, they'd eventually be successful but that's not a realistic scenario.
"drone ground war in Ukraine"
DeleteBe very cautious about extrapolating from the Ukraine ground war to naval combat. In naval combat, there is no masking terrain. Everything is out in the open and visible out to the radar horizon or beyond, depending on the type of detection system. Further, every ship has a fairly extensive and powerful radar system as well as passive detection systems. 'Sneaking up' on a ship operating on a war footing is very difficult to do.
"OTOH, a EPF from a harpoon sized warhead will easily go through over a meter of RHA and then some."
DeleteDo you have a link or ideally video that supports this claim? One meter of hardened steel? That is ten times more than I'd suspect.
Totally agree on your comment on aircraft and laser guided bombs -- I wasn't saying that aircraft can do this today (or in the past or in the future), just saying that targeted hits would be very deadly if they could be delivered (i.e. it would be like a modern weapon system hitting and disabling even a 1940's era battleship). I was in essence referring to the potential vulnerability of even well-armoured ships IF micro-targeting (and quick attack -- faster than the ship's OODA loop can respond. I think the risk is some weapon system (probably located in or on the actual the sea, not the air) that is hard to detect (because of its size, composition, etc -- a smart and maybe even mobile 'mine' so to speak). Something that crowds congested areas. That, because of their ubiquity, network effects, distributed processing power and secure (line of sight?) communication gives them enough sensor awareness to detect a target and obtain a fire solution. Something that might combine hard to find, short range aerial drones (or other, broader perspective intelligence assets) with target identification and targeting. Maybe something with a bit of reach (e.g. short ranged missile) for very quick, hard to react to strike attack targeted to vulnerable mission kill, mobility kill, or sensor kill weaknesses. In a congested sea route or littoral, it could be deadly (perhaps until cleared). IED's for ships that deny access locally to known and likely travel paths. Demining is so hopelessly under resourced, the initial 'appearance' of such devices could really crimp the effectiveness of high value naval assets for quite some time (until recognised and reliably countered).
DeleteAs for the Ukraine comment, the purpose of that comment was not to compare land war with naval warfare, only to make the point that sometimes, in warfare, the balance between attack and defense gets very unbalanced (for a period of time, sometimes quite unexpectedly), especially if defensive research has been under-resourced. Today, armour, infantry and artillery are being hit with good success and lack the deployed weapons necessary to counter (enough) of those strikes (because of technology and tactical advances, under-investment, old-mind sets, etc.). Something similar happened with naval aviation in the mid-to-late 1930's (when aircraft rather suddenly became much better naval strike assets, leaving warships heavily underpinned with regard to anti-air capability). Same with Japanese optical gunnery and night fighting capability (which was convincingly overwhelmed by radar guided guns by 1944). Given enough time (and funding), defense and offence balance out, but during times of rapid change it is possible to get caught 'on the bounce' to disastrous effects' (e.g. naval battle of Sinop).
DeleteGoing back to my 'what if' for a minute, think of very local anti-access denial zones full of (relatively cheap, but effective) products that are not used in the open seas but in areas where ships are known to congregate, especially if terrain, other ships, etc clutter the area. It doesn't find you as much as you find it (unexpectedly). Something that doesn't have to be entirely static (like a mine field), and that uses number (and faster related strike munitions) to cover the (relatively short range) distance to target. Clearing some (but not all) clears a lane for a while, but not continuously (especially if re-seeded is cheap and relatively easy. Long term, they would be countered (continuous sweeping? finding and shooting the archer of all these persistent and smart arrows?). But the introduction of such a system (like the introduction of shell guns or longer range effective gunnery or capable aircraft etc) provides a window of advantage. If war happens while that window is open, oh boy.
DeleteFinal thought, my musings here are not really a push back against armour (it might even make armour more necessary) or on well-armoured ships (like battleships), just my imagining that we may have collectively gone too far down the road of long range detection, long range strike, open ocean conflict (a la WW2), and something much nearer-in, small (but targeted and fast), asymmetric might be possible today (or soon) that wasn't conceivable previously. The technology may not be there yet (hard to say), but I know longer think it science fiction. Any way, sorry if I took us off track a bit. All the best
Delete"Going back to my 'what if'"
DeleteThere's nothing wrong with engaging in 'what if' speculation but it is important to note that the end result of such speculation is unproductive. By definition, it is impossible to counter 'what if' weapons. For example, what if someone suddenly develops a weapon that is invisible and has Star Wars like vaporizing lasers that can instantaneously make an aircraft carrier vanish? We have no defense against that so we should immediately retire all our carriers, just in case.
'What if' makes for fun speculation but not realistic analysis.
If you want to explore 'what if' scenarios, try exploring the other side of the 'what if', meaning the defensive armor side. What if naval ship designers developed and incorporated some of the land based armor concepts like composite armor, layered armor, explosive reactive armor, void space armor, sacrificial armor, offset armor, etc. Add to that the ship equivalent of the active protection systems on tanks. Why, ships would be invulnerable! The point is that 'what if' works on both sides of any subject.
Or, what if we had small surface drones with powerful lasers that could sweep through areas where anti-ship weapons are known to congregate, zapping them with instantaneously disabling laser shots? The drones would be small, hard to detect, and impossible to counter and would wipe out any enemy anti-ship weapons.
Of course, none of the above exists.
Fair points -- sorry again if I took this off track a bit. Your proposal is practical here and now. My 'worry' is that we, like in the past, about to be presented with yet another 'factor' in warfare (self-directed weapons in previously 'safe' areas immune to intensive, coordinated enemy action) that will significantly change how we manifest the old factors of concept of operations, design, doctrine, training, weapon system distribution, etc that forces us to use armour, etc in new and unexpected ways. Battleships replaced ships of the line in function, but did so with increased system complexity (e.g. other assets like destroyers and cruisers and aircraft to scout, target, defend, attack) -- because the threats (torpedo boats, aircraft, submarines, mines, etc evolved into dimensions previously unanticipated (or under-developed). At some point, probably soon, if not already, we may be adding a new dimension to worry about (not a sci-fi 'what if' but more of a 'we see that steam engines are really developing, we better consider what it means" kind of moment. My reaction is probably more to the word 'battleship' (since it is such an iconic image). What comes next (I suspect) will be something even more complex and fragmented than the 'fleet' we became so comfortable with after WW2 (carriers, cruisers, destroyers, battleships, etc.). Still 'what if', I know. The value add of my comment, if there is in fact any value add (a fair question), is that we are probably going to have to see a total 'rethink' of what a ship is, what a fleet is, how it operates, etc. that will make what comes ahead to be as different as 1914 vs. 1814, or ocean-going cannon-armed galleons vs lateen sailed galleys. The concepts: firepower, armour, speed, range, sensors, replenishment, repair, etc. will remain, but the way it will be combined, distributed, carried out totally different. Just a statement saying that putting everything new in perspective, we are probably going to be shown (by someone somewhere soon) where the direction forward will be. Since 1945, we've had a relatively continuous refinement of air dominated operations (whether it is missile or aircraft), but that probably won't be true going forward. I just hope that, like the Royal Navy in the 1850's and again in 1905 it is the US, not China (or someone else) who figures out what that new model is and keeps our relative lead.
Delete"The value add of my comment"
DeleteDon't get me wrong. There's nothing wrong with 'what if' speculation as long as it is rooted in what's plausible rather than totally sci-fi. We need people to think about future threats and capabilities. HOWEVER, the thinking needs to be balanced on both sides of the subject. Thinking only about, say, the future offensive developments can lead to focusing on a weapon that is easily negated by readily attainable 'what if' defensive developments.
For example, your concern that some new development(s) will enable future aircraft to loiter over a ship and pinpoint attack it has to be weighed against the readily foreseeable and plausible future development of, say, the defensive laser which would make loitering aircraft an impossibility and would provide impenetrable point defense even against pinpoint targeted bombs/missiles.
So, by all means, consider 'what if' scenarios but do so for both sides of the particular subject.
Appreciate the thoughts and I really agree. On a separate but related topic, I want to make a request of you to think about something and let me know your thoughts, if you are amenable. I respect your insight, experience and opinion (sorry it is long in two parts).
DeletePart 1 My concern about 'smart persistent lethal' weapons is not something 'in the air' loitering invulnerably above a ship -- instead, it is something in the water, on the water, or below the water in a ship channel, harbor, littoral, choke point etc. Something that is stealthily pre-positioned there in mass (perhaps by 'civilian' traffic, from land, from undersea, maybe - but not likely - by air). Something like a network of sleeper cells, waiting to be activated. Something that discriminatingly hunts the things (the silhouettes, emissions, thermal or radar profiles, whatever) that it is programmed for, and that attacks in a targeted, asymmetric way when it strikes (preferably from multiple directions simultaneously). It doesn't need to be a complete weapon system in and of itself. Maybe just the sensor. But lots of them and they are sensors that can communicate with and arm multiple strike weapons somewhere else already prelocated in the area (e.g. in a shipping container, on a boat, on a truck, on another submersible in the same field, etc). Given that things decay over time, would be detected, etc perhaps this swarm of 'eggs' is 'laid' just prior to conflict (or periodically during a conflict). It's basically autonomous, and placed and forgotten (until we basically run into or near it and its trigger conditions are met). It's in an area that has previously been safe from mining and submarines in prior conflicts (because the systems available to do something like this needed to be deposited there by a rival naval force (which is hard if an opposing naval or Air Force is there to deter them), manned of limited endurance, etc. But nowadays, those constraints are gone (or substantially altered) because of AI, miniaturisation, battery and power generation improvements, civilian access, improvements in sensor and targeting systems, etc. The sensor (short range) exist today and the means of strike can be whatever devious minds can conceive whether it is true mines, torpedos, missiles, limpets, speed boats, etc. Ideally, the strike is synchronised in some ways to overwhelm CIWS and countermeasures with limited warning (if such systems are even 'on' in just a congested environment). Perhaps the nodes are somewhat mobile and even take actions to 'hide' when being hunted. I don't think that these capabilities are too far out in terms of sci-fi (and for the sake of discussion allow that this is perhaps possible and that they could be employed).
Part 2: This is scenario, as described above, IS CERTAINLY FANCIFUL (but not crazily unrealistic in my opinion) -- but that is not what I would really want your opinion on. (In other words, maybe what I've tried to describe is complete bullshit in its details but that doesn't mean that someone with much better knowledge and context couldn't come up something that would have the same net effect (and actually work). What I want to know about is how do we respond to the denial of key areas of operations 'in our backyard'.
DeleteIf something like this is possible (now or in the near future), it would impact our critical replenishment, refuel, repair, transit, and rest facilities (and deny them to our fleet -- at least until the threat is truly understood and countered). The question in my mind is 'how might a fleet handle the denial of critical replenishment, refuel, repair, rest, and transit assets and still manage to fulfil its missions during this period of 'acute backyard accesss denial'?
I could imagine that closure of facilities to civilian traffic and access, rigorous patrolling and sweeping, underwater barriers, etc would be used, but not all such locations could be 'cleared' of civilians or civilian traffic or underwater visitors in a future war (closing Guam to all outsiders yes but not the Singapore Strait). For sake of argument, assume that our initial countering efforts are ineffective. If our logistics tail is uniquely severed like this what do we do?
In some ways, this is the converse of the ballistic missile threat to Guam. Right now, we are dealing with the threat that Guam (or elsewhere) might be closed down due to ballistic missile threat (i.e. if they can't destroy the ships because they are out to sea than they might destroy our bases instead). They would use long range weapons to destroy far away targets. Would such a intelligent 'mine' concept effectively do the same thing but in a different way (i.e. short range weapons just outside our door)? Is there a new or different way to repair, replenish, refuel, rest crews in theatre even if such 'home bases' are off limits? I'd love your thoughts on this -- I've been thinking about it but have clear limitations in my knowledge of what happens in these areas today and what might be possible in the future with regard to such operations. The answer to ballistic missiles are hardened operations, anti-ballistic missile defence, counter-offence, redundant sites, rapid repair etc (like we practices in the Cold War with regard to air fields). But what if the problem is in the seas just outside our port's door? If our 'home' activities are interrupted (granted this is a what if, but let's assert for sake of arguments sake that 'is' interrupted for a sustained period), how might things work from your perspective? Really just curious, not trying to be argumentative here or sci-fi speculative. Thanks in advance.
I must confess I'm not totally grasping your concept. What you're describing already exists. They're mines. Mines exist that sit and wait for the trigger conditions. That satisfies most of your sensor characteristics. The only real difference is you mention the possibility of separating the sensor from the weapon although I'm not sure what the inherent advantage of that would be. Besides, we kind of already have that with mine-torpedoes. A mine-torpedo sits until a trigger signal is sensed and then the torpedo activate and travels to the target as opposed to a true mine which is immobile and must be 'in contact' with the target. That accomplishes the same thing as your separate sensor and weapon in that the sensor is located away from where the weapon effect occurs.
DeleteThe counter, as you know, is sweeping which mimics the sensor trigger signal.
As I say, I'm at a loss to understand exactly how you see your concept being different from current mines to any significant extent.
Here's a few other considerations:
A small, waiting sensor package has a limited lifetime due to power. Sonobuoys, for example, have a lifetime of a matter of hours.
A small, subsurface sensor has no capability to send a signal to a separate weapon that is not very, very near in which case they aren't really separate. A floating transmitter could be released, I suppose, but, again, it would be low power, short range and there would still be the problem of getting the signal to a submerged weapon.
Short range, low power sensor signals are easily susceptible to jamming/interference.
And so on.
Why don't you try describing how you think your concept differs from today's mines. That might help me understand where you're going with this.
Got it. All fair points -- I suppose I could try to elaborate a bit more, but the question I am really trying to keeps changing (sorry about that -- as you respond to me, you answer one question in my mind only for yet another to pop up). First I was thinking about the impact of precisely targeted shots (and you addressed that), then that got me thinking to scenarios where such shots might be delivered at short range unexpectedly (which you addressed) to now about alternative models of ship support. Every time you 'scratch an itch' I realise that there is something else that seems 'open' that I wonder about. I realise that it may be frustrating for you (but it is actually a sign of success -- you address my question but it leads me to some other step). So, to be clear, I feel 'answered' regarding precision targeting and smart mining, but I still have the final (I promise) question regarding maintenance and support facilities. Assume for a moment that the bases are inaccessible (either through some scheme like I proposed or through successful Chinese ballistic missile attacks or sabotage or whatever), what happens? In WW2, there really wasn't any real chance that Japan would successful destroy or suppress Pearl Harbor or Perth (let alone San Diego) so there was always a place to retire to to refit, repair, rebuild, rearm, recuperate, etc. (and many minor facilities in between). Now, these sites are reachable. Replenishment underway is not new (by sea or air) but repair and rearmament (for vertical launch systems) a problem (especially with the chronic under-investment and poor management these past decades). If China invades Taiwan tomorrow and puts some 'zero day' plan into affect on our support facilities (and succeeds), what options does a modern navy need to stay in the fight in terms of support facilities, ships, etc. Are there new capabilities, ships, systems, we need to consider (out of the box ideas other than protect what we have better so that we don't have a problem)?
DeleteThere actually was a logical progression in my questions that got me here: 1) targeted weapons are one solution to armor, 2) what kind of scenario would allow targeted weapons a chance of success (have to be a short range shot), 3) what kind of system would allow for short range precision shooting (the equivalent of a naval anti-access denial zone in a supposedly friendly area), 4) what kind of damage would losing access to critical support facilities have on operations and are there new ideas that should be considered to minimise these risks. If I was smarter, I'd have gotten there sooner (but you were a part of me getting there -- so thanks)
There are many scenarios that could inflict serious damage and disruption to our naval support activities other than mining ports. For example, see The Next Pearl Harbor - Shipyards which talks about the vulnerability of shipyards and, in particular, the very few massive cranes we have that allow us to build and repair ships. Without those few cranes, we're dead in the water as far as building ships or repairing them.
DeleteThanks for the reference (I hadn't seen that post before). That's not good news (and actually depressing, given how things are trending). There is just so much rot all over our society, it's sad. Anyway, thanks for fighting the good fight.
Delete"I hadn't seen that post before"
DeleteThe accumulated wisdom of the blog dwarfs the imagination. I urge you to make use of it !
I don't think anybody sensible would dispute that it's possible to build modern warships that would be harder to damage, because of armour. They might be significantly different from traditional battleships. The harder question would be if they were cost-effective, since they will be more expensive than current ships. Answering that properly needs a design study and a Concept of Operations.
ReplyDeleteOne thing that obviously needs to go into the CONOPS is "how might an enemy attack such ships?" and I can see two obvious ways.
One is anti-radiation missiles, which are really designed to attack radar antennas. Those can't really be armoured, although you can fold them up and/or retract them under armour, at least in theory. Fragmentation warheads will shred deployed antennas, and enemies can build those readily, although getting them through defences to their detonation positions is a problem.
The other attack technique that would work is heavyweight torpedoes that detonate under the keel. Responses to that are making the ship stronger and its equipment more shock-resistant, although this drives up costs, torpedo decoys, and trying to invent practical anti-torpedo weapons. Again.
I think that the value of a battleship is that it would provide the ability to bring sustained destructive power that could be used against enemy coastal targets without needing to deploy a carrier battle group, risk pilots, or expend costly tomahawk missiles.
DeleteEven the Iowa class if it was updated would also force a potential enemy to devise and field weapons and tactics to deal with the armored firepower of these ships.
Could they counter the Iowas?
Sure.
Make them do it.
Lutefisk
"The harder question would be if they were cost-effective, since they will be more expensive than current ships."
DeleteThey wouldn't have to be. For example, consider a heavily armored Burke AAW ship. An AAW ship does not need a helo, flight deck, hangar, etc. to support flight ops. Thus, all the construction money that currently goes into aviation expenses could, instead, be redirected to armor and we could have a fully functional AAW Burke with heavy armor for no additional cost.
If we eliminated crew lounges, game rooms, and all the extra crew amenities that we've discussed on this blog, there's more money available for armor.
So, the issue isn't money, it's redesigning the ships to be purpose built WARships instead of our current glorified cruise ships.
"anti-radiation missiles"
DeleteAs you noted, sensors can easily be embedded inside armored, retractable shelters. Another approach is to emphasize passive tracking and engagement via IR/EO. CIWS has optical tracking although I'm unsure whether that is sufficient for engagement or not. However, there's no reason it couldn't be. Aircraft engage with IRST so there's no reason a ship couldn't have a dozen or two IRST sensors which give no emissions for anti-radiation weapons to home on.
Also, a battleship, unlike, say, a Burke with a single CIWS (hit it and the Burke has no more point defense), would have dozens of SeaRAM and CIWS. Recall the anti-aircraft weapons density on the WWII battleships? So, even if an occasional anti-radiation missile got through, it could only take out one or two weapons and there would be dozens left. It's a battleship! It's designed to take hits and keep fighting. We've forgotten just how powerful and survivable battleships were. They're called BATTLEships for a reason!
A heavily armoured Burke sounds nice, but I doubt it's that easy. Armour is not bulky, but it is very heavy. The things you're eliminating are bulky, but not terribly heavy. Stripping that weight won't give you enough weight budget to armour the ship very strongly. Also, Murphy's Law of engineering tells us that the weight saved won't be in the right places, so the centre of gravity will move and the trim will be wrong.
DeleteYou can certainly design an armoured cruiser with a hull shaped like a Burke, and a similar displacement and engines. However, you'll have a lot less superstructure, and the interior arrangement will be different. It's a different ship class.
"It's a different ship class."
DeleteOf course it is! That's the idea!
"harder question would be if they were cost-effective"
DeleteDepends on what we would use them for (CONOPS). The issue is not cost, it's value. Is there a mission set for a battleship that justifies the cost? Carriers are hideously expensive but we believe that their value is sufficient to justify their cost.
Is there a battleship mission set (CONOPS) that justifies a modern battleship? I'll leave that one to you. Everyone has a different opinion about that!
Armor seems like such an obvious element of a warship, and such a natural complement to CIWS, that the lack of armor in modern US Navy ships makes me question how serious the organization is about fighting actual wars.
ReplyDeleteOne question that I have about the use of armor is, how much armor is necessary to mitigate the blast effect of a modern anti-ship missile?
I would like to see the navy be serious about testing thickness and composition of armor against a full array of possible unfriendly anti-ship missiles and start incorporating this knowledge into new ship designs, and retro-fitting existing ships if it makes sense.
Lutefisk
Excellent article, Thanks!! A frequent anecdote which was common when I was on active duty is pertinent:"What happens after a Kamikaze strike on an Iowa class BB?--answer: The ship holds sweepers".
ReplyDeleteI wonder if a sabot-type warhead for an ASM would penetrate a battleships armor in the same manner as 120mm sabot tank round or the following variants of the Hellfire ATGM:
ReplyDeleteAGM-114K Hellfire II Optimized Missile System (HOMS)
AGM-114M Hellfire: Same as the K variant with the exception of having the forward warhead removed and replaced with a blast fragmentation warhead.
AGM-114N Metal Augmented Charge (MAC) Thermobaric Hellfire: "The missile is also effective against caves, light armor, trucks, radar vans, buildings, light bunkers, command and control sites, patrol boats, light ships, the superstructure of heavy ships, deck mounted weapons systems and troop concentrations."
I would bet my life insurance on using the N variant against a battleship. Since the Navy currently uses variants of the Hellfire (a useful purpose for the LCS).
Source: https://www.globalsecurity.org/military/systems/munitions/agm-114.htm
Tomcat, I think a sabot round would probably penetrate as would a HEAT round.
DeleteBut what damage would it do?
Keep in mind that penetrating a tank's armor is likely to be fatal inside the extremely small confines of an armored vehicle.
Penetrating a ship's armor is unlikely to hit anything vital, especially if the ship's interior is laid out advantageously.
Lutefisk
A tank sabot round flies at very high velocity, because it's light, compared to an HE round. The sabot makes it full-calibre so that the gun can fire it, and then falls away. The armour-piercing dart hits at very high speed and penetrates because of that.
DeleteMissiles develop speeds with rocket (or jet) engines, and their impact speed isn't responsible for most of the damage they do. To fire an armour-piercing dart with a missile, the warhead has to be a one-use gun, and the Hellfire missile is too small to carry a gun with serious penetration.
The way to penetrate thick armour with a missile is to use a shaped-charge warhead. The Hellfire has one of those for use on tanks, but it's a bit small for battleship armour. A Tomahawk-sized missile, however, could carry a shaped-charge warhead that would blow through any historical battleship's armour.
"A Tomahawk-sized missile, however, could carry a shaped-charge warhead that would blow through any historical battleship's armour."
DeleteDo you have any evidence to support that? I ask not to argue with you but to remind that we're in an entirely different regime with large missiles and battleship armor as opposed to small anti-tank missiles and relatively thin and light tank armor. I've never heard of any tests remotely at this level so I have to wonder if the results scale up?
battleship armor isn't any thicker than most tanks today when considered as RHA. Many tanks have aspects that are beyond 500mm RHA. The Iowa class belt was only 300mm and the turrets were 500mm. Hellfire missiles would have no issue penetrating that depth of armor.
DeleteThe main issue with using hellfire would be the low level of secondary effects due to the much larger volume of ship. This is primarily down to the hellfire only have a ~9kg warhead.
OTOH, a EPF from a harpoon sized warhead will easily go through over a meter of RHA and then some. In addition, the level of secondary effects would be sufficient to do some real damage both to the immediate compartment and at least ever neighboring compartment. In fact, for a warhead mass the size of a harpoon, you could easily have a tandem config each capable of going through over a meter of RHA.
Really it comes down to the age old issue of kinetic (battleship guns) vs explosive energy (EFP).
"RHA"
DeleteWhere did you get RHA values for battleship armor?
As you know, RHA is not a constant characteristic of a piece of armor but is an indirect equivalency valid only for a specific weapon-armor interaction. So, again, where did you get battleship RHAs? I'd love to see the data!
I'm unaware of any actual testing so I assume someone has done some theoretical calculations and I have a deep-seated mistrust of theoretical calculations since I encounter and document failed weapon theories all the time as I operate this blog.
So, by all means, tell me more about your data. That's sincere. I'd like to learn something!
The logical extension of your claims is that if the relatively thin armor of a tank can produce functional thickness of 20"+, why haven't ship designers spec'ed armor for ships. It would seem a no-brainer; battleship equivalent armor on a tugboat!
Most of the armor tended to be STS on battle ships except for the belt which was effectively a modification of krupp FHS. Ballistically, RHA sits between the two for those projectiles that can be decapped.
DeleteThe thing is though, that EFP have such high velocities that face hardness has minimal effect on their penetration. Which makes most battleship armor no more effective against them than standard RHA. You are looking at avg hardness and tensile strength to combat EFP in a monolithic armor.
The armor of tanks isn't that thin (M60 had 4-6" plate with 10" LOS glacis and turret front was 11" thick ) esp when looked at from the ballistic angles. Tanks are specifically designed such that the plates that are hit are hit at angles which increases the required distance to penetrate. Doing that for a ship's belt would run into difficulties.
The Soviet heavy weight ASM's had 2000lb HEAT warheads that, according to Soviet specs, could burn a hole about 2-3 ft around and 15-20 feet deep. Add to that any unburned fuel.
Delete"RHA"
DeleteSo, just to be clear, there is no data for battleship RHA equivalencies? You're offering your own thoughts on how it applies and what numerical values might be? That's fine but please present such statements as speculation rather than as established facts. Your conjecture might be correct or it might not be.
"EFP"
I'm unaware of this being done on anti-ship missiles although perhaps this is what's referred to as 'semi-armor piercing' in Russian claims? The point is that I'm unaware of EFP on a larger size scale. Would it even work? How effective would it be?
On smaller, anti-tank missiles, my limited understanding is that EFP produces a small hole which, if successful in achieving full penetration, is damaging to the small, confined space of a tank compartment but would it produce much of an effect against a ship?
I'm also unsure how large an EFP could be incorporated into a large anti-ship missile without negatively impacting sensor and electronic space and location requirements.
"hit at angles"
Tank armor is angled relative to the ground because most anti-tank weapons (enemy tank shells, ground launched anti-tank missiles) travel horizontal to the ground although there are, of course, anti-tank missiles that perform a pop-up maneuver. For a ship, the incoming missile is almost always elevated and diving down towards the target ship to varying degrees. Thus, vertical armor on a ship DOES produce an angled impact. In fact, it would an unlikely occurrence for a missile to hit perfectly perpendicular to a ship's armor (if ship's had armor!).
I assume RHA equivalencies are predicated on perfect (0 degree) obliquity. Thus, the effective RHA is likely far less than the estimates you offered, I would think.
"RHA"
The entire RHA topic is quite fascinating and I know little about it. It would be very interesting to see any actual work done on this as it applies to ship armor and larger anti-ship weapons. Let me know if you come across anything.
"Soviet heavy weight ASM's had 2000lb HEAT warheads"
DeleteThe favorite sport of Soviet/Russians is wildly exaggerated claims, most of which prove to be false. Witness the actual performance of Soviet/Russian weapons in the Ukraine conflict versus pre-war claims.
Absent some sort of unbiased test results, I flat out don't believe any Soviet/Russian claim.
for RHA its pretty easy to compare data from http://www.navweaps.com/index_nathan/metalprpsept2009.php with COTS RHA like https://www.ssab.com/en/brands-and-products/armox/product-offer/armox-370t-class-1
DeleteEFP/shaped charges have been done on large scales, bigger than can fit in most missiles (basically oil drum sized). they scale pretty linearly with size both for bore hole diameter, depth of penetration, and secondary effects. Its hard to get published data, esp on steel, vs feet of concrete, but here's two reference points: https://ndiastorage.blob.core.usgovcloudapi.net/ndia/2011/gunmissile/Tuesday11808_Shire.pdf and https://apps.dtic.mil/sti/pdfs/ADA414599.pdf
WRT to incorporating them, they would be incorporated the same as they are for all other weapons which is exactly the same as most other warheads: they sit between propulsion and seeker. The timing on the fuse is such that the seeker portion is sacrificed/destroyed as the warhead goes off
Most AShM missiles are designed either for top down deck/super structure attack or side on hull attack. Pop-up is generally only done when a non-hull attack is designated.
Sidewinder Tuff Rock????? What's that?
DeleteThe test described in the paper appears to have produced a 10 inch diameter hole to a depth of 19.5 ft in Sidewinder Tuff rock, whatever that is.
Having absolutely no comparison between this rock and real armor, I can't evaluate this result at all.
As far as your Navweaps reference, it appears that you're attempting to match parameters from various materials/armors referenced in the Okun work to a manufacturer's armor plate. That's like equating a race car and a pickup truck because they might happen to have a similar cylinder bore diameter. Tragically, many of the WWII era armor manufacturing techniques appear lost to us, today. Trying to equate two pieces of armor is almost impossible, I fear.
Until someone tests actual missiles against actual armor, I can't see any valid comparisons or extrapolations. An armor expert (are there any today?) might do so but that's not us.
What? The material properties of the plates can and have been tested. The numbers of significance are provided in both the manufactures numbers (which are tested according to the appropriate standards) and the Navweaps tables. They both provide the same sets of numbers and are directly comparable (well once you convert from MPa to KSI or from KSI to MPa). These are the exact same numbers that *all* the data and conclusions from Nathan Okun are generated from.
DeleteNone of the WWII era armor manufacturing techniques are lost to us. Its just that Krupp FH doesn't provide much benefit these days over standard RHA which is cheaper/easier to produce. The whole point of Krupp FH was to decap projectiles.... These days no one uses capped projectiles. Weapons either use shaped charges/EFP or kinetic energy penetrators(sabot or otherwise).
And we test actual missiles against actual armor all the time. And we see the results all the time in Ukraine currently.
"And we test actual missiles against actual armor all the time."
DeleteI assume that's true ... for small weapons against vehicle armor. I'm unaware of any test involding anti-ship missiles against battleship type armor. Trying to extrapolate vehicle size armor and weapons to ship size is a completely unproven exercise. Do I need to list all the military systems that have looked good based on calculations and have failed when scaled to real world applications?
Pretty sure there haven't been any, simply because nobody manufactures battleship armour at present. The expected result for current warheads would be loud noises and scorched paint.
DeleteScaled-up HEAT warheads, which don't exist at present, should be able to penetrate traditional battleship armour, but as you say, this would have to be tested. Building those larger HEAT warheads would not be a major problem, but US defence contractors could doubtless make it expensive.
Since building large HEAT warheads would not be a significant problem for the Chinese or Iranians, building heavily armoured ships with composite armour
would be a better idea. That resists HEAT warheads quite well, although it's less effective against high-velocity darts.
The current answer to those is some form of reactive armour although the current methods of building that will probably need modifications for use on the scale of a ship, rather than a tank.
Penetrating heavily armoured ships is actually a potential use for hypersonic missiles.
fyi, scaled up heat warheads do exist and are in wide use: BROACH
DeleteDo we know why naval armor mostly went away after World War 2? Could it possibly be that, with the advent of nuclear weapons and the assumption that future wars would be nuclear, there was a perception that no amount of armor would protect a ship against those?
ReplyDeleteI THINK armor went away because the weight increased the amount of power required to move a ship through the water. Spruances were built like Coke cans because one of the acknowledged tradeoffs was fuel economy.
Delete"I THINK armor went away because the weight increased the amount of power required to move a ship through the water."
DeleteNo. As demonstrated in every ship class built in WWII, armor was incorporated into ship designs while maintaining 30 kt speeds. For example, the Cleveland class cruiser which was around 600 ft long (versus the Burke at around 510 ft) carried several inches of armor in various locations while being capable of making 32 kts. When armor is part of the design (as opposed to an after construction add-on), armor weight does not negatively impact speed.
From what I recall from research long ago, several battleships were hit by Kamikaze attacks that sunk 66 Allied ships. None suffered even minor damage, although lots of AAA gunners outside the armor were killed.
ReplyDeleteI’d only been SECNAV for 37 days but I figured, ‘What the hell. Let’s roll and see what we get.’
ReplyDeleteMr. Ingalls, Mr. Nucor, Mr. Lockheed, Mr. Bechtel and Mr. Raytheon are sitting around my Pentagon conference room table.
“Gentlemen”, I start off, “Thank you for coming because I want a proof-of-concept for a surface ship capable of surface sea control of all area within the 2500km area of our Tomahawk cruise missile. I want you folks to get together and show me if what I want is possible. Why? Go look up Zeihan on youtube. What I want includes:
Mr. Ingalls, You have the hull. I want a armored battleship-class platform. You’ll be working with Mr. Nucor.
Nuclear powered and all electric. Work with Mr. Bechtel. More than 86,000 SHP because you’ll need more than a Tico to drive a armored ship through the water. I don’t care how big the ship is.
2-4 steerable electric drive pods; no extended 20+ yard propellor shafts strung under the hull; because battle damage susceptibility.
200 or more VLS cells; I don’t care if you use the MK-41 quad packs or something else. Assume a combination of Harpoons and Standards. Do we still make ASROCs? But no sonar- We'll have dedicated ASW platforms for that.
Assume a SPY-6 and everything else that a Burke has.
I want a armored battleship. NO LESS armor than on the New Jersey. Pay particular attention to how you’re going to armor the top of the VLS cells.
No hanger deck because no helicopters. But I need deck space for helo unrep.
Mr. Nucor, I’m serious about the armored battleship concept. Go look up the New Jersey and tell me if you can manufacture armor components we need. See this picture of the 17.3 inches surrounding the conning tower on the New Jersey? That’s your minimum. If you tell me we have wondrous new materials that can cut that to 2 inches, for example, I’ll entertain the suggestion; but you better be able to back it up with physics.
ReplyDeleteMr. Bechtel, I want the battleship powered by 2 S1B reactors; just like you have planned for the Columbia. Why not A-series like we use in the carriers? They’re too damned big and complex. Mostly too big in terms of space required. Remember, this is a electric ship; you’re spinning electric generators for the propulsion pods not driving screws. If the math for a couple of S1Bs doesn’t work come back and tell me so. By the way, EACH reactor has to be able to power the entire ship 100% independently. We’ll have two for redundancy.
Mr. Lockheed and Mr. Raytheon- I want multiple lasers for close in defense. Phalanx too; yeah don’t worry about that part because we can talk to those guys separately. But get started on thinking about something like the RBU-6000 for torpedo defense. Why we don’t have equivalents in the fleet now I don’t know- But I want them on the new ship. The 3 of us are going to talk about a considerably different drone capability, too, but I’ll call a separate meeting for that.
Gentlemen, give me a broad-brush design. Tell me if this is possible. We’ll worry about specifics in later phases. But know this: I want a collective response from all of you 30 days from now. I recommend you spend 3 weeks working in-house and then another week talking integration among yourselves. Use todays technology; no conceptual leaps. Think of it as a whiteboard exercise culminating in a powerpoint presentation. Now is not the time for determining costs; we’ll do that later. But know that I want the first of class floating in 3 years. Follow-ons assuredly. Mr. Ingalls, you're lead for this effort.
Ms. Moneypenney is now passing out authorization for $30M dollars each company for this modest exercise. No extensions. No excuses. Just bring me what you can so we can start the discussion. Guys, for a million dollars per day you can put your company’s experts in a warehouse-sized room full of whiteboards.
Since everything will be mostly off the shelf you should be working with known requirements in terms of space, weight, etc. Any questions?”
Mr. Ingalls breaks out in to a flop sweat. Loosens his tie while looking over his glasses. “Mr. Secretary, we wouldn’t even know how to start. Nobody has designed a battleship in 80 years or so. What you’re asking is… a lot.”
I’d anticipated this response. “At minimum, go find the plans for the New Jersey class. Start there. Improve it where you can. In fact, I’ve already asked my staff for that design work and should be able to forward it to you tomorrow. Your biggest complication, way I see it, is the armor work. So now I’ll ask Mr. Nucor to work independently, yet closely with you, to translate 1940s armor designs to 2025 manufacturing capabilities. IF we can’t manufacture metal this big and this thick we’ll go back to the drawing board.
“Thankyou all for your time. See you in 30.” I walk back to my office and pick up my phone.
“Ms. Moneypenny?”
“Yes, Mr. Secretary?”
“Get me Elon Musk. I want a 4-hour meeting followed by dinner. I’m happy to go to wherever he is.”
“Yes sir. I’ll get right on that.”
Nice closing!
Delete"One of the common rejoinders employed by battleship critics is that modern anti-ship missiles would quickly and easily sink a battleship. "
ReplyDeleteIs this actually a common rejoinder by battleship critics? Or is it that gun-armed battleships are largely irrelevant (or at best massively cost-ineffective) in modern naval warfare. A giant warship with lots of armor and defensive systems to protect a primary armament of huge guns with a paltry range of some tens of miles.
Sure you can put missiles on them too, but there are far more cost effective ways to bring missiles to the fight. The battleship's effective "cost per offensive shot" is vanishingly small. It'll rarely, if ever get in range to use its guns.
Looking at the big gun ballistics, one wonders why the big rush to expensive hyper-sonics when a supersonic cruise missile with an armor-piercing heavy warhead would do plenty of damage. That is not difficult tech--the AGM-28 Hound Dog (USAF) flew at Mach 2.1 with a 1750 lbs warhead (albeit nuclear) over a thousand klicks in 1960 (reference is wikepedia). Not small by any means (think half-scale fighter jet). But if you thought of one as a one-way drone, then you could use an amphib carrier pack to launch 30 or 40. Not as good a rate of fire as a Battleship cannon I grant, but then a 16" had a range of less than 30 miles, and they had to fire a lot of rounds to score a hit as precision was not its forte.
ReplyDeleteIt should be noted that against missiles which use shaped charged explosives (i.e. almost all of them) space is also a form of armor. When you see army vehicles in Iraq with the metal bars around them that is their purpose: the warhead is detonated the bars and most of the explosive force is then dissapated in the space between. The Navy used the same trip on some of the riverine vessels (concerted LCMs mostly) having what looked like empty cans around them. This was successful against RPG's so long as they could keep the sailors from using them for storage which negated the spacing effect.
ReplyDeleteObviously a foot or two wouldn't work against an AShM with a a several hundred or larger warhead. But you took a big ship with a lot of internal volume like a big bulk cargo ship or an America class LHA, you could put several interior bulkheads with empty spacing without messing with the vessel's weight. If made into compartments these spaces could also provide extra emergency buoyancy.
I'm not saying this is as good as real battleship armor, but rather something that could be done with existing vessels. While not conducive to an LHA running aircraft, it would be a cost effective way to turn a new build LHA hull into say a cruiser capable of taking damage and continuing to fight.
A new class of battleship would be ideal, but lets face it, not something Congress would authorize anytime soon. And quite frankly I have my doubts that the current military contractors could build a battleship since they have failed to produce any major vessel successfully whose design does not date to before the year 2000.
"When you see army vehicles in Iraq with the metal bars around them"
DeleteOne of the real baffling omissions in naval development has been the utter lack of armor research and application. Land based armored vehicles have come a long way from WWII while naval armor has done almost nothing. Why haven't naval scientists worked on adapting land based armor concepts like composite armor, layered armor, explosive reactive armor, void space armor, sacrificial armor, offset armor, etc. Add to that the ship equivalent of the active protection systems on tanks. We haven't even scratched the surface of ship armor and we, inexpicably, we seem to have no interest in doing so.
"the warhead is detonated the bars and most of the explosive force is then dissapated in the space between"
DeleteCan work for older RPGs, but is a lot less effective with newer weapons that have stronger shaped charge HEAT jets that will just cross the distance no problem.
To put things into perspective, a modern RPG-7 round can penetrate 27 inches of steel RHA armor. A few feet of standoff isn't going to do that much to protect your hull (but it's still a roll of the dice, and an RPG cage is cheap to employ, so there's no harm in carrying it).
The way the RPG cage works on Stryker is really aimed against the RPG-7 and how the fusing mechanism on RPG-7 rounds work; the idea is that striking the metal slats of the RPG cage will break or short out the fuse of the RPG-7 round, so that when it hits the hull, the fuse is damaged and the shaped charge doesn't initiate. This is less effective against newer AT weapons like the RPG-29, let alone heavy AT like Carl Gustav, AT4 or ATGMs like Spike or Javelin, but the RPG-7 is the most prolific light AT weapon in the world, and is the most likely weapon to be fired at a Stryker (because heavy AT is generally assumed to be held in reserve for servicing Abrams).
"Add to that the ship equivalent of the active protection systems on tanks."
We can see clear parallels between softkill (Shtora IR jammer) and hardkill (Trophy, Afganit) APS systems and the softkill EW (SEWIP) and hardkill point defenses (CIWS, RAM, ESSM) on warships. Years ago, I'd assumed that navies would be developing IR blinders to defeat IIR seekers (NSM and LRASM have imaging IR and radar seekers), but it seems that instead of making ship-sized Shtora, the Navy is looking at lasers as the IIR blinder weapon, which is not what I'd expected, a decade ago.
I think there's been more attention to tank softkill measures in open sources because tanks fight with flight times of 2 seconds tops, and there's a lot of effort being made into an APS that can detect and intercept an incoming sabot in that short short time. Conversely, the naval question is a longstanding, understood problem: detection and engagement at the radar horizon. The principles are the same, but the level of challenge in different.
That's not how cage/slat armor works. It works by damaging the warhead geometry before the fuze is ignited. HEAT warheads' penetration capability is highly dependent on the geometry of the explosive and metal liner. Stand off distance hasn't really mattered for many decades
Delete"Semi-armor-piercing" shells are literally just halfway points between classic AP shells and HE shells.
ReplyDeleteThe only things I see getting through ships armored to heavy cruiser and battleship level armor are HEAT warheads and kinetic energy missiles(the us developed some for anti tank use but then never fielded them). Either way little after armor effects will be felt on most of the ship because of the volume. It's especially important to remember that layered/spaced armor arrays work exceptionally well against heat warheads and allow massive RHA values for relatively little weight.
If the full suite of solutions developed for armoring tanks was employed on a ship it would be very very difficult to mission kill its ability to fight out to the horizon at least. The kind of optical and thermal sensors that can be mounted on a ship that large and armored is quite impressive.
Although I've seen no data on it, I've seen many suggest using a HEAT warheads as a precursor to a normal explosive warhead to weaken the armor just enough so that the main warhead can pass through and detonate. It seems like a reasonable idea, but it would be defeated by many concepts developed for tank armor
Delete" precursor to a normal explosive warhead "
DeleteConceptually, that's exactly what the armor piercing cap on an AP shell is and does. What's old is new again!
yes, the difference is that a shaped charge/EFP is a small fraction of the weight for the same effect. The main issue with the armored cap is that its very heavy and bulky but the effectiveness of most of that weight in penetrating is pretty minimal. When looking at penetration, only the tip weight of the cap is effectively useful for the force of penetration. And likewise, mass is much less effective than velocity for penetration.
DeleteThe other issue is the fracturing of physical armor caps which isn't much of an issue with high velocity metal jets (aka shaped charges/efp). The other nice thing about using a precursor charge penetrator is it is independent of the velocity of the projectile.
" fracturing of physical armor caps which isn't much of an issue with high velocity metal jets"
DeleteI don't know that that's true. It stands to reason that a missile striking at anything other than a perfect 0 deg obliquity runs the risk of having the EFP either damaged to the point of uselessness or rendered ineffective by the angular action instead of perpendicular action. For example, the most extreme case of 90 deg obliquity would result in the entire EFP action being directed parallel to the face of the armor instead of directly into it. Any angle between 0-90 deg would produce a proportionally reduced EFP effect with the jet 'drilling' at an angle and thus having to penetrate much further to achieve complete penetration. The same, of course, holds true for an AP cap.
Finally, bear in mind that battleship armor was designed to resist shells impacting at Mach 2+ so missile speed is not really a benefit and for the most prevalent anti-ship missiles (the subsonic ones) the missile speed likely has little to no effect.
My ultimate conclusion is that until someone produces actual test data, I see no evidence that missiles can penetrate battleship armor. They might but there's no valid evidence for it. Just conjecture.
EFP/shaped charge jets go though highly angled plates all the time. That's what they run into most of the time on things like tanks where there they are most used.
DeleteMissile speed is immaterial to the speed of the EFP/Shaped charge which are well into the hypersonic range.
And just as a point of reference, this weapon type exists today and is fielded by multiple counties within multiple glide/cruise missile all using variants of the BROACH warhead. Unfortunately penetration data is classified.
EFPs and HEAT warheads are at the moment the most weight effective threats for modern armor to counter. The downside for tanks is that to effectively counter them in a cheap way, you need alot of volume which is in relative abundance on a ship
DeleteAre any of the existing BBs as museum ships in sufficiently good shape to be shipped out to actually see how durable thay would be?
ReplyDeleteIf you're talking about actual missile versus armor tests, that would be accomplished by firing missiles at sacrificial test plates of armor. As I've often recalled, the Navy did this many years ago with what I recall to have been Harpoons against actual battleship armor plates with the Harpoon accomplishing nothing.
DeleteThe analogous test would be the way we test rail guns against blocks of steel to measure penetration.
As CNO and others mentioned, it is one of the strangest things in military affairs that naval armor has been pretty much dropped by every navy and no interest whatsoever of bringing it back with modern equivalent.
ReplyDeleteI bet a WW2 88mm or 1950s 100mm tank round couldn't put a dent in frontal armor of a 2022 modern West tank like an Abrams or Leo 2. And forget ACTIVE systems of protection, those rounds might not even get close! And even of if it does penetration, look at survivability that we build in to make it possible that crew has a chance. It's not like tank development stopped after WW2 and everyone decided: "yeah, we not going to bother anymore with armor!"
There's a YouTube video where they tested like a 1950 car and a modern 2010 or better car on safety impact that they routinely do these days. The old car just folds and would have killed eveyone inside. The modern car has crumple zones, impact mitigation, components take the impact, engine doesn't land on driver lap, air bags, side bags etc etc, at worst, driver would suffer a broken leg. I think too many think of WW2 armor for ships like this old fashion just lots of steel and old BB hull shape so why bother?!? How different would naval armor look like if we did it today?!?
Again as a civilian example: a Boeing 707 has a tube fuselage, swept wing, podded engines etc so doesnt look completely out of place even today and it inaugurated the modern transport jet design look. The modern equivalent B777 or A350 generally looks the same and designers of the old 707 would get it BUT they would marvel at the changes and materials that would reflect 70 years of advancements.
It is weird the disconnect between the Army and Navy on the issue as you point out. I mean sure the Army has now added the Trophy system to the other non armor defenses of the new SEP what v2-v4? versions of the M1A2. But thay did not say well that does it let's toss all the third generation depleted uranium armor upgrades and any of those ERA plates and anti RPG grills we have laying about who needs them. We can roll back to just the M1 armor and even that seems silly now.
DeleteThe way modern tank armor is built older anti-tank guns and projectiles would generally embed themselves partially into the turret since lighter weight materials are usually in front followed by very hard and dense backing/structural plates
DeleteThis is MM-13B
ReplyDeleteI haven't commented for a long time, but here goes.
There was a time, 18th and 19th centuries, when most of the armies of the modern world gave up armor. After firearms had become predominate on the battlefield, armor became less important. Why bother with armor when a bullet could shoot through it? Clashes with bayonets and swords were common, during which armor would have been useful, so there may have also been the issue of resource allocation. It may have been seen as a better use of resources to raise a larger army, versus a better equipped one. Pre-industrial revolution, it may have been seen more beneficial to use limited metal working resources for manufacturing weapons, such as cannons, rather than manufacturing armor. Perhaps there were cultural issues, such as armor was viewed as outdated. During battles of the 19th century a trend was observed, a significant percentage of battlefield casualties were caused by indirect fire. Flying debris is much easier to stop than direct rifle and machine gun fire. In WWI the world saw metal helmets return to the battlefield. Those helmets were inexpensive to produce, and a soldier could stay in the battle after getting hit on the head by a chunk of flying debris. Armored vehicles (tanks) also appeared during WWI. In the hundred years following, armies have adopted great advancements in armor for both personnel and vehicles.
After WWII, navies abandoned armor much like most armies had done before. We have speculated as to why, and this blog has done a fine job of demonstrating how armor on ships would be beneficial.
Anti-ship missiles, capable of defeating battleship armor, COULD be produced, but at what cost? I believe they would be very expensive, leading to very limited inventories or cutting back on other production.
" I believe they would be very expensive, leading to very limited inventories or cutting back on other production."
DeleteExcellent insight. We (all of us) have a tendency to limit our discussions to only the most extreme (unlikely?) scenarios. For example, we debate the impact of the world's biggest missile against the world's strongest armor (a battleship). What we should be debating is the far more likely scenario of small anti-ship missiles effectiveness against moderate armor.
In any battle/war, there is far, far, far, far, far more mundane munitions being flung around than there are exquisite weapons. A ship is far more likely to encounter run of the mill rockets, artillery, bullets of various calibers, naval shells, Hellfire size missiles, and small anti-ship missiles than monstrous anti-ship missiles. We need to protect our ships against the multitude of common threats and not give up just because we can't guarantee zero damage from the world's biggest missile.
Thanks for the kind words. I think a good example of mundane versus extreme is exemplified by the amor police officers wear. Their normal armor is a vest capable of stopping common handgun rounds. Most rifle ammunition can defeat this armor. Should we say "all a criminal has to do is use a rifle, therefore the armor is useless, don't wear it"? No, the officer is way more likely to encounter a criminal with a handgun than a rifle. The other extreme is to always wear full tactical gear, but that would make the normal daily duties very difficult. Head and limbs are still unprotected, but they would be more difficult to protect. So we've arrived at an armor scheme which protects against the most likely danger without greatly impacting job performance.
DeleteOne of the earliest armored ships was the Joseon (Korean) "Turtle" ships. Admiral Yi Sun Sin used them to defend against Japanese invasions during the 1590's. Analysis of Admiral Yi's ships and tactics would make a great historical battle blog post. Lots of littoral combat with each side using very different ships, weapons, and tactics.
MM-13B
Very interesting article. However, be careful when comparing the Harpoon with contemporary soviet missiles. The Harpoon warhead is tiny compared to a P700 or P500. The P700 has a 700kg warhead of which roughly half is RDX or whatever explosive they now use. Also, a P700 has over 2.5x the KE of a 16 inch super heavy shell. Armour shatters (especially face hardened one) when faced with large quantities of explosive. It is never immune to HE. A Harpoon (early versions with 100kg warhead)with RDX has about 270 MJ of CE. A Granit has 2079MJ... This puts the Harpoon roughly on par with the energy needed to overcome the tensile strength of RHA equivalent of the Iowa (1000MPa) and granted, back of the envelope calculations on my end but... The Granit is a full order of magnitude larger than the energy required. This means that even halving it (because the charge is not shaped so half the explosion would go backwards and be in effective n... Less than half because of the traveling velocity of the missile and the inertia applied to the explosive warhead but let's keep it simple) the Granit or basalt would still have a lot more energy than required to overcome the tensile strength of the steel armour and literally just crack it. Of course this is in theory. But the math checks out and it is not a simple soviet claim of magical properties in their kit. It is just normal RDX energy density and tensile strength of steel.
ReplyDeleteOk. Had a bit too much fun so calculated the total explosive plus kinetic energy for Harpoon with early 100Kg warhead, P500, P700 and super heavy shell shot by Iowa class battleships:
DeleteHarpoon:
298MJ
16 inch super heavy shell:
356MJ
P500:
1.87GJ (of which 1.34GJ are from the explosive warhead alone)
P700:
4.54GJ
The energy required to fracture a 1m2 slab of Iowa RHA equivalent armour is about 307MJ.
This would mean that the tests you saw with the Harpoon track. As the Harpoon has the smallest warhead and is the slowest of the missiles providing less energy at point of impact than a 16 inch shell. Though it could still create spalling I guess depending on the part of the ship it hit and of course, pop up attacks are its thing.
The P500 would likely not penetrate on the kinetic impact alone but the warhead is the largest. The explosive energy is more than enough to crack the armour belt at the point of impact. Maybe more. It is an order of magnitude different.
The P700 is just... Well the kinetic energy alone is enough to just penetrate the armour belt depending on deformation of the missile body and it's rigidity but enough to severely damage it. The explosive energy is also massive and if there was penetration prior to exploding then yeah, it would shipwreck the Iowa. If not, then it would still likely cause catastrophic damage. It is just way too much energy to deal with. I mean the kinetic energy alone is an order of magnitude larger than what the armour tensile strength should be able to cope with. Add to that the explosive reaction afterwards... It is about 15x the needed energy to compromise Iowa's armour. Again, back of the envelope calculations for fun but still physics is physics.
I've got some questions about your calculations and conclusions.
DeleteYou didn't list the mass and velocity you used in your calcs but I'm guessing you used the maximum published values. I did a kinetic energy (KE) calc for the P-700 and I used a speed of Mach 2 which is greater than its listed cruise speed but less than its listed max. Seemed like a reasonable, actual, operational speed but who knows. I used a mass of 5500 kg since the missile fuel is a significant portion of the weight and would be largely expended by the time impact occurs.
m = 5500 kg
v = 686 m/s
this gives
KE = 1.294 MJ
This is equivalent to 309 kg TNT. Not insignificant, to be sure, but I wouldn't think it would be instantaneously shattering battleship armor. Applying your 'half' rule (seems reasonable), that would reduce the KE contribution to 155 kg TNT equivalent.
The other aspect that I have concerns about is that you're failing to incorporate reality into your conclusions. For example, while the P-700 may represent the largest missile a potential enemy possesses, it is not commonly available within the Russian navy (which I don't see us ever fighting) or the Chinese navy (not sure what their largest missile is?). Thus, the LIKELIHOOD of encountering such a missile is low. The far more common case would be smaller anti-ship missiles like the C-8xx family (somewhat equivalent to a Harpoon). Thus, the premise of the post is still valid.
It is also important to note in any discussion of explosive impacts on armor that the angle of impact is critically important. A 90 deg obliquity is the maximum effect but is the least common real world case. 'Glancing' blows are far more likely with the result that the explosive force is largely dispersed in directions other than directly into the armor. To be fair, you somewhat noted this.
I'm offering these thoughts as a discussion not an argument to be won or lost.
Maybe you could clarify your KE calc parameters and consider how, if at all, the other points alter your thinking?
"Armour shatters (especially face hardened one) when faced with large quantities of explosive."
DeleteI have never heard that, at least not as applied to battleship armor. Do you have a reference for that?
As a related side note, have you read Okun's work on Navweaps site?
I did use Mach 2.5 on my calculations as I assumed that was terminal velocity but low altitude velocity is only Mach 1.6. mass is 7 tons as per Wikipedia and other online sources. This changes the kinetic impact to 1.04GJ which is still significantly higher than the threshold of 307MJ but with the caveat that deformation of the missile will of course dissipate some of this energy. The total blast energy remains the same and so the total will be 3.05GJ or about 10x the energy needed to penetrate. Of course if it bends and doesn't penetrate the armour some of that explosive energy will be sent outwards which will reduce the energy by about 50% but if it does penetrate then kaboom.
DeleteThe P700 is of course not likely to be encountered by the USN but I was thinking about cold war when Iowa and Kirov or Oscar 2s could in fact meet. I have been reading the recently declassified Global War game second series and so my brain kind of put two and two together I guess. In fact, what prompted me to Google this was when in the war game the Iowa engaged a Slava cruiser in the med together with one Aircraft carrier, the carrier was disabled with Granit missiles and the Iowa suffered no damage. Which made me question how much did the USN know about the full specs of the Granit and Shipwreck missiles. And then I came across your blog where you mention you did the test with the Harpoon and armour and it kind of makes sense if that is the data the USN used aas a proxy for soviet capabilities.
I don't have any sources per se on naval situations at hand but on land, when the Panthers and Tigers were faced with the IS2s and the ISU 152s, the German engineers noted that tanks with face hardening applied had significantly less resistance to HE shells of large calibre as the armour instead of bending, cracked. Physics also says that because you take the crystal lattice of steel and make it tighter making it harder and less flexible so when the threshold of energy is exceeded instead of bending, it breaks.
As for bigges AShM in China... Well to heir short and medium range ballistic missiles. And those are it for any fleet. I remember running the possible scenarios where the US fleet engages with China and the barrage of cruise and ballistic missiles was insane. The US could stand to lose up to 7 carriers in such an endeavour. And Ballistic missiles would be going through deck armour which is much thinner.
For cruise missiles they have a ton. From subsonic 1960s era stuff to really modern scary stuff like the YJ12 and the CX1. Their hypersonic program is also well ahead of the US with platforms like the DF ZF operational since 2019. And those are mid range ballistic missiles with hypersonic manoeuvrable vehicle. Ime. Pretty much uninterceptable on terminal approach.
"mass is 7 tons"
DeleteNote that mass is the initial, fully fueled mass and, as I assumed in my calc, would be substantially reduced during flight as the fuel is consumed. I assumed 1500 kg would be consumed and the impact mass would be 5500 kg. The concept is correct but the amount of fuel is pure, but reasonable?, speculation on my part. The net result is that your calculated KE would be significantly less.
"noted that tanks with face hardening applied"
I don't know anything about WWII tank armor but I would be cautious about applying the behavior to ship armor as I suspect they were markedly different. Okun's work may have detail on this. I seem to vaguely recall that ship armor was constructed in layers with different properties but I'd have to review some references to be sure.
Note that as regards speed/altitude, most missiles of that era were designed to cruise at higher altitudes and then drop to sea skimming for terminal approach. I assume the P-700 does the same but I don't know that for certain. If it does, that would decrease the impact speed and reduce the KE.
You are correct. I don't know the fuel consumption rate but if we assume impact at max possible range, 1.5 tons is likely correct. These missiles have a different targeting approach. While early after launch they climb and travel high, once they are far enough away one of the missiles stays high and datalinks with the rest of the swarm target designations. They automatically assign targets between themselves and use the horizon to mask their approach. If lead missile is shot down, next missile in the formation climbs up and resumes tracking. We are still talking about close to 9x the energy required to defeat the equivalent thickness of RHA.
DeleteFace hardened armour has the same problems irrespective of where it is used. It is just physics. If an object is harder, once enough strain is applied it is more likely to crack than Bend.
For reference, the famous image of the imprint of a kamikaze plane on the side of a battleship, that plane carried a kinetic energy of about 50MJ assuming 600 km/h and the explosive payload would likely be a couple of hundred of kg of TNT or equivalent. Which would result in an explosive force of .837GJ yet the photo shows no damage which means much of this energy was dissipated and it does cover a much wider area and not sure where the detonation of the explosive happens which makes a huge difference (the explosive energy will reduce tby the cube of the distance and then is distributed via the surface area of the sphere. For these calculations I have been considering the surface area of the missile and a point blank detonation as it was what these missiles were designed to deliver but the difference in the explosion happening one meter away from the armour and point blank is about 10,0000x)) The crux here lies in the difference in Kinetic energy and how the energy is propagated. For all intents and purposes, the P700 behaves more akin to a naval shell than an airplane. And even if the charge is not shape charged the speed of impact and point of explosion alone are enough to warrant a closer look.
If the kinetic impact is enough to crack the armour (and it should be then there will be a crack and serious enough deformation that the explosive charge will act in a quasi shaped charge fashion. If the armour suffers no damage (unlikely as the difference in KE alone os far too large imho when doing material science at Uni applying a 3x force to anything from concrete to stell beams is instant snap or sheering through torsion) and the explosive detonates away from the armour spreading the energy from the explosives over a wide area (instead of r=0.1m, r=1m) then the armour would hold. Again these are interesting points to discuss but pretty academic if your focus is on modern enemies for the USN (instead of cold war wargames for funsies like me). And besides China, I can only think of the upcoming administration and the excesses of the military industrial complex as the main enemies of the USN.
If you haven't already, be sure to read "Armor for Dummies"
DeleteSo many people focus on whether or not armor can stop, with absolute invulnerability, the biggest missile ever built or that ever will be built. That's NOT the main, or only, purpose of armor. The post I just linked explains this. Armor is invaluable even if it can't stop nuclear bombs with total invulnerability.
Oh for sure. Armour has many uses. Since medieval times. Mind you we are talking in different scenarios and my last message was a bit of a garbled mess as using phone and blogspot and long messages don't gel. My discussion is mostly centered around cold war wargames and how to make a naval boardgame that is fun to play and realistic. Entirely different beast to what you are attempting to do. To answer your question about building a modern armoured ship or not, that ship would have to be very different. Armour would most likely be centered on the deck as that is the point of impact of some cruise missiles and ballistic missiles and then the active protection of both fleet assets and point assets like CIWS. I think fleet defence doctrine and the coming of the missile age spelt the end of the battleship as a viable platform. Even in a non carrier environment would you really have much to gain from something like an Iowa battleship when compared to another Arleigh Burke or three?
Delete"would you really have much to gain from something like an Iowa battleship when compared to another Arleigh Burke or three?"
DeleteAbsolutely! There's no comparison. We've discussed this in many ways on many posts so I encourage you to make use of the archives.
Another aspect of armor that you need to keep in mind is the structural arrangement. Armor was not, as is usually imagined, applied as a single layer of steel on the outside of the ship (though that was the case in some retrofits). As an example, the Iowa class side armor arrangement consisted of an external de-capping layer and multiple internal layers including the main belt which was inclined at 19 deg. The incline was calculated to increase the effective thickness by around 40%, if I recall. The various non-"armor" longitudinal and transverse bulkheads were thick (a few to several inches) steel structures which, though not formally considered armor, nevertheless acted as such. And so on. The point is that armor is a scheme with many components that act together to confer protection rather than a single piece of monolithic steel plate.
DeleteSure. But that armour plate was not meant to stop missiles and RHA equivalent is good enough imho. The decaping layer would do nothing to a missile and the angling of the belt was also made taking into account battleship shells not supersonic telephone poles with 10x the total energy of a battleship shell.
DeleteIf we are talking about developing a boat that has passive armour schemes meant to protect against missiles then possibly. The Navy seems to be moving towards even more active systems with laser guns which will lead to introducing some form of ablative armour on anti ship missiles I am sure. So current thinking seems to be active armour > passive armour. And I am not sure I disagree.