Monday, June 21, 2021

Armor Compendium

I’d like to try an experiment.  One of the problems with a blog is that readers come on board at various times and the newer readers have missed the preceding discussions.  This leads to re-addressing concepts in the comments that have been previously covered but are unknown to the newer reader.  Of course, it is the responsibility of the reader to be familiar with the archives but …


So, my thought is to occasionally present a compendium and summary of links to previous posts on a single topic as a sort of historical guide and one-stop ‘catch up’ assembly of knowledge.  I’ll try to present the links in some sort of logical order to guide the reader through a logical progression of the posts.


The first topic will be ship’s armor – always an interesting and [inexplicably] controversial subject.




Let’s start by describing the ‘problem’ which is the Navy’s near total abandonment of armor.  This post does a nice job of describing the current armor ‘problem’ and visually demonstrates the effect of varying steel thicknesses:


“Ship Construction and Naval Armor”


Here’s some additional discussion of the vulnerabilities caused by lack of armor:


“Survival on the Modern Battlefield”


One of the main problems with eliminating armor is that a modern ship’s main weapons and sensors – the ship’s entire reason for existence! – are completely unprotected and subject to damage, destruction, and inoperability due to even simple shrapnel, to say nothing of actual direct explosive hits.  We’ve built ships that can be mission killed by minor shrapnel damage!  Here’s some discussion about the failure to armor a ship’s main weapons and sensors:


“Weapons Armor”


Having a good feel for the scope and ramifications of the problem, we turn to the overall rationale for naval armor.  This post presents the basic rationale for ship’s armor and is the single most important post on the subject:


“Armor for Dummies”


The following post reminds us about the painful lessons learned by the Navy when we abandoned armor and moved to aluminum construction.  Despite these graphic lessons, the Navy has returned to aluminum in the LCS classes:


“Lessons Learned and Forgotten”


There are, unfortunately, a great many naval observers who believe that ships cannot carry armor without either sinking under the weight or, if they don’t outright sink, will be so weighed down as to lose all speed and range.  This post addresses those misconceptions and reminds us of the fallacy of such beliefs by highlighting WWII ships that carried a great deal of armor and still managed to not only stay afloat but to exhibit great speed and range:


“Armored Ship Misconceptions”


Have armor requirements changed from WWII days?  This post presents a conceptual description of how to armor a modern ship in response to modern threats, including anti-ship missiles:


“Conceptual Armor for Modern Ships”


Many observers believe that it is impossible to armor a ship against torpedoes.  Here’s a post that disproves that belief and goes on to discuss some torpedo armor concepts:


“Torpedo Lethality Myth”


For those who might want a bit more in-depth discussion of the application of armor and how it is structurally arranged:


“Transverse Bulkheads”


So, what is the future of naval armor?  Well, it’s not bright:


“Time Stands Still”


Finally, if you’re more interested in land combat, here’s a discussion of the Marines and their love-hate relationship with armored vehicles.


“Marines and Armor”




So, there you have it.  Almost everything you’d want to know about ship’s armor – or at least what I’ve covered so far!


As I said, this is an experiment so let me know in the comments whether this kind of compendium is worthwhile and, if you think it is, what other topics you’d like to see compiled in this manner.


  1. Weapons Armour

    You talk about the armour of the 5"/38 mount but the Mark 28 was only mounted on Battleships.

    Destroyers like the Fletcher and Gearing carried Mark 30 and 38 mounts with a all over 0.125in (3.175mm!) or armour, would that even stop a rifle round?

    The issue for destroyers was top weight and stability to carry the main gun and torpedo armament plus the expanded 40mm and 20mm AA guns and all the new radars and gun directors means a lot of top weight.

    The Cleveland, Baltimore and Des Moines cruisers had 0.75inch or 19mm of armour on their 5"/38 mounts but WW2 built cruisers are a lot bigger than a Burke.

  2. US navy conducts Full Ship Shock Trial on Gerald Ford.
    I know you were calling for this sort of testing and I would be interested in your comments as to how realistic this was and if there are any rumours on the results.

    1. I have nothing to offer, at this point, because no details are yet available. I'll comment when some information becomes available.

    2. Do you find this kind of post helpful?

  3. “Lessons Learned and Forgotten”

    You Wrote

    "Jim, you may recall that the F/A-18 Hornet was the result of the Lightweight Fighter competition in the early 1970's. The winner of that competition was the YF-16 which latter became the Air Force F-16. Despite winning the competition, the YF-16 was rejected by the Navy. One of the major reasons cited for rejection was the single engine of the YF-16. The Navy wanted a dual engine aircraft. So, no, I don't think the single engine lesson is a myth. Any thoughts?"

    My response to this 2013 conversation.

    The Navy didn't want the same aircraft as the USAF so was playing politics.

    From the F6F Hellcar, F8F Bearcar and A1 Skyraider of the piston era to the F9F Panther/Cougar, FJ-2/4 Fury's, F4D Skyray, F3H Demon and the F-8 Crusader of the jet age a single engine was fine for USN adoption.

    Two engines historically was because the aircraft was big and heavy enough to need two engines more than for any safety requirement.

  4. I like this "unification" type post. PS like your blog even tho' the more I read it the more depressed it makes me!

  5. I am from Ukraine though but I've been reading your blog since the autumn of 2018. And in every leisure time still continuing reading your archives or list of different topics placed on the right side of this blog. Some posts are so wonderfully interesting that I'm trying to read them more a few times. Thank you ComNavOps for your honest and decent work in lighting the truth in the US Navy. This blog develops thinking for simple people what is more than valuable for current time when the journalists, experts and other analysts are lying in their websites, organizations, writing about distributed lethality conceptions, boat navies, LCS and so on.

    In my country there isn't a blog what is doing a research work, describes failures, learns the forgotten lessons, overturns a lies...

    The Americans should be very thankful to You for a such great job for your country! May God speed you and saves the USA from the within and foreign enemies!

    1. I am humbled and I thank you! I'll continue to try to provide education and enjoyment.

  6. CNO, thanks for putting this together. There's so much information on this blog it's hard to see everything.


  7. I am extremely happy that you did something along the lines of this. If you forgot, I propose something similar to this in the last "Open Post" albeit in a different manner.

    Now, I would go one step further and propose you add a specific page right next to the tab section (the one containing the Comment Policy and Fleet Structure) that could serve as a "Table of contents" where it presents all current and future Compendiums. I look forward to see the Decentralized Warfare compendiums or maybe Transformationalism?


    1. I do remember your suggestion and it actually inspired this attempt. I know it isn't exactly what you were suggesting but consider this a baby step in that direction!

  8. Good stuff CNO. I dont think I was here in 2013 so reading some of the older posts.

    Small "complaint....I noticed there was already Anon and Anonymous, which is OK but my problem is its really hard something to follow or respond to Anon or Anonymous when there's more than 1! I appreciate how Lutefish and some others put a name at the bottom so its easier to respond or comment to the correct just makes the thread easier to follow and respond. My 2 cents.

    1. Yeah, the anonymous comments present a challenge. I encourage people to add a name at the end but it's not required. I sympathize with people who are tired of creating yet another account and username so I'm okay with anonymous comments although the informal name at the end works just as well. I'll keep encouraging people to add a name.

  9. The "Compendium" is a brilliant idea. It gathers most or all of relevant ComNavOps posts on a specific topic under one umbrella - almost like book chapters. Invaluable aid to new and old readers alike. Please create more of these (time permiting)

    Go to the head of the class!

    1. "The "Compendium" is a brilliant idea."

      Thanks but credit for the idea has to go to reader 'lpnam9114' who suggested something along this line in an earlier open post.

      For readers who make suggestions from time to time, I may not act on every suggestion but I do take them all under serious consideration so, by all means, keep suggesting and thanks!

  10. Here are a couple of youtube videos I have found useful. Both dealing with armor and how it is made.

    I think too many people think of armor is only for complete protection from some projectile, mine, you name. Once those folks realize that that armor is to mitigate damage.

    I have learned a great deal about the US Navy, especially its thinking. Especially, at how people can still have jobs after such boondoggles as the LCS ships. Also, how come there are so many Admirals and Captains?

  11. When the navy ditched armor, it did so in a world of 18 inch battleship shells, Long Lance Torpedos, and guided Fritz bombs. It was right to judge that no armor in the world could readily repel hits from such weapons.

    Now we live in a world of helos shooting ATGMs and pintlemounted machine guns at ships. The guns are 2-5 inches, and alot of the missiles are man portable.

    I dont expect a destroyer to eat an Exocet or hypersonic missile for lunch, but it should be able to shrug of a RHIB full of tangos carrying AKs, RPGs, and LMGs.

    So long as SS goatbanger hasnt been packed to the gunwhales with explosives and a contact fuse on the bow, a destroyer shouldnt suffer more than scratched paint from such plebian firepower.

    Such armor would also be quite effective against alot of what enemy attack helos and fighter/attack aircraft can bring to bear. I know the Argies did alot of strafing and rocket attacks against the RN using A-4s, Mirages, and Pucaras.

    We (globally) ignored ships getting sunk and mission-killed by what used to be considered small arms to focus on the Belgrano getting sunk (by suprise, with its crew at mess, and its hatches/doors open) by a heavy weight sublaunched torpedo. A weapon capable of killing practically every ship on the ocean.

    "Pay no mind to the modern ships getting wrecked by 20mm cannon fire. t
    That old *COUGH* Light *cough* cruiser was torpedoed and sunk. That proves armor is dumb."

  12. "When the navy ditched armor, it did so in a world of 18 inch battleship shells, Long Lance Torpedos, and guided Fritz bombs. It was right to judge that no armor in the world could readily repel hits from such weapons."

    ?????? You might want to read the Okun series of papers. They're available on

    I fear you may have missed the entire point of armor. Please read "Armor for Dummies", linked in the post.

  13. It's for members-only, but the USNI has an article from Lieutenant Commander Raymond Dennis, USN, titled If It Stops Floating, It Stops Fighting about the need for ships to have armor in order to be able to take a strike and continue to fight.

    1. "in order to be able to take a strike and continue to fight."

      An oft repeated refrain on this blog!

  14. This is an excellent first step towards pointing your readers in the right direction regarding a long-neglected issue for the US Navy.

    Are you going to make another compendium of posts regarding the importance of "excess" manpower aboard a ship given your opposition to "optimal" and "minimal" manning? How about the continuing importance of large-caliber (8" or bigger) naval gunfire, in terms of versatility, reliability (shells from large-caliber guns aren't affected by weather, for example), costs compared to naval airpower, risks, and usefulness compared to missiles (guns don't need a long time to change target co-ordinates, large-caliber shells can't be easily shot down mid-flight, nor jammed/decoyed, etc.)?

    I think a video like the one below would help to make your case regarding the cost argument of large-caliber gunfire vs naval airpower:

    1. The video's main points are valid enough but the presentation and methodology are spotty and suspect. For example, the video claims that a Nimitz carrier can generate 9 sorties per hour. Obviously, that's a highly misleading (outright false!) number derived from an averaging of sorties over a 24 hr period. In reality, a carrier generates pulses of high intensity sorties and firepower. The video then goes on to calculate and compare carriers to battleships based on this misleading 9-sortie figure. And so on.

      All in all, the video is very poor quality reasoning although, as I said, the ultimate conclusions are reasonably valid. The conclusions are valid but the arguments border on fraud.

    2. Hmm, I guess I'll know better than to take the videos in that series at face value. Will you make a compendium of posts on having reserve manpower onboard warships, as well as a series of posts on large-caliber naval gunfire and its advantages compared to the alternatives of naval airpower and missiles, though?

    3. "Will you make a compendium of posts on having reserve manpower onboard warships, as well as a series of posts on large-caliber naval gunfire and its advantages compared to the alternatives of naval airpower and missiles, though?"

      I'm open to any subject for a compendium. I'll take a look at those topics and see if there's enough posts/information to warrant a compendium. Note, though, that this is just an occasional effort so it might be some time before those topics rotate to the top of the post queue, if they're even done! Rest assured, however, that I'll give them serious consideration. Off the top of my head, those sound like pretty topics!

    4. I'm glad you think those two are "pretty good topics." We could seriously use some 8" guns in the US Navy by now, if not the reactivated 16" guns of the Iowa-class battleships.

      How would you address the manpower problem though? Is there a serious shortage? Are you in favour of reinstating conscription to address that shortfall?

    5. "How would you address the manpower problem though? Is there a serious shortage?"

      There is no shortage of manpower. What there is, is a serious misallocation of manpower. Until I assemble a compendium on the subject, check out this post: "The Manning Myth"

  15. In one of the referenced posts about armoring something like a modern ship (like a Burke), you stated that attack by an anti-ship ballistic missile is unlikely because they can't be targeted at sea. I'm not so sure.

    I do agree with your thought that, during wartime, it will be very difficult for China to target our ships at sea. We would of course sink any of the maritime militia ships that got anywhere near our ships, of course.

    But I wonder if these weapons might be a useful "first minute of war" weapon.

    If I'm President Xi, and I decide that I'm going to have to fight the US (after finally giving up on intimidating us into capitulating and sailing off, leaving the whole Western Pacific to him) I think what I'd do is to mount a massive assault with ballistic missiles against all our bases in the region and as many ships at sea as I could find, with no warning, maybe even during peacetime. Since the status prior to the first launch would be "peacetime", they could use their maritime militia (of which they have many thousands) to follow every one of our surface assets in the region and radio back the exact positions of those assets. We can't really sink them in peacetime, right? Of course, once the first blow is struck all those ships will be sunk, but by then it might be too late.

    You've said in the past that we'll see the attack coming since the Chinese would have to move a lot of forces around in preparation. Two thoughts on that:

    (1) We've been caught by surprise many times, from Pearl Harbor through Korea, through the original Iraqi invasion of Kuwait, through 9/11, through the Russian takeover of Crimea. I understand that we actually had advance indications of some of those but failed to act on them. What makes us think that things will be different going forward?

    (2) It's true that they would need to move a lot of forces around to prepare for an amphibious invasion or major fleet operations, but my understanding is that their mobile ballistic missile forces are ready to launch on almost a moment's notice and could start an attack with little or no visible preparation. Aircraft can then be moved around fairly quickly to continue suppressing the bases, while they start the other major mobilizations after the missile attack, when our major forces in the region would already have been neutered.

    1. Your entire comment is, essentially, a Chinese version of Pearl Harbor. The sort answer is that it is not possible to completely stop a country that is willing to commit a peacetime 'Pearl Harbor'. If you concede the first strike to a country then you accept that they can some significant, initial damage to you.

      That said, you are wrong about several things:

      1. We had more than adequate warning about the incidents you list. Pearl Harbor, for example, was known in detail and almost to the date and yet, inexplicably, we did not act - or did not act wisely - to protect ourselves. The same holds true for the others. Even a terrorist 'Pearl Harbor' like 9/11 gave all the indications we needed to act and yet we did not put the pieces together well enough and did not act on the pieces we had.

      2. We have never been caught by surprise. There are ALWAYS indicators of impending war/attacks. A country doesn't wake up one morning and attack out of nowhere. Relations break down, threats are traded, militaries are brought to higher levels of readiness, ballistic missiles are positioned and tweaked for maintenance, surveillance assets are moved into place, etc. Unfortunately, we have a habit of ignoring the warning signs or simply not acting on them. For example, we saw Iraq's invasion of Kuwait coming but we did not act ahead of time. The invasion began on 2-Aug-1990 and yet Wiki reports this:

      "On 25 July 1990, April Glaspie, the U.S. ambassador to Iraq, asked the Iraqi high command to explain the military preparations in progress, including the massing of Iraqi troops near the border."

      So, we had at least a few weeks warning and we actually had seen tensions building for months before that with disputes over oil, debts, and territorial claims. Invasions don't happen instantaneously.

      I can disprove the 'surprise' nature of all your examples but you can research them and see it for yourself.

      Even the examples you suggest of using fishing fleets or militia type assets to provide targeting during peacetime can only do so for targets close to China. To find targets, like carriers, out in the open ocean, China would have to sortie large numbers of vessels, UAVs, aircraft, for whatever to search for US ships. That activity would be noted and would provide the opportunity to react prior to attack.

      3. Your comment indirectly raises the issue of forward deployment. Forward deployed forces are not only vulnerable to a first strike, they are almost certain to be destroyed (the Asiatic Fleet of WWII, Force Z, etc.) while accomplishing nothing. The US should reconsider its forward deployed posture. For example, a single forward deployed carrier is certain to be hit in the opening moments of a war and will be lost. So, why have a carrier there. It's not accomplishing anything, anyway, and is just being positioned to be lost. We need to rethink our forward deployments.

    2. Well, I believe I noted that we did in fact have advance indications of many of these but did not act on them. But that isn't really any different from actually being caught by surprise, now, is it? The results were the same. Why should we assume that things will be different in the future?

      Regarding the maritime militia, they have plenty of time to build ships that have longer range. In fact, they already send fishing fleets almost all the way across the Pacific. The image I have is that they'd just wait outside the port at Yokasuka, or wherever, and follow the ship from there wherever it goes. If they did this routinely for a long time, it wouldn't constitute a warning.

      I do agree with your point 3, that forward deployment (at least in the Western Pacific) is starting to look very risky. We really need to rethink that.

    3. " The image I have is that they'd just wait outside the port at Yokasuka, or wherever, and follow the ship from there wherever it goes."

      If tensions have been rising and war is on the horizon, however distant, no ship/group commander is going to allow a fishing vessel to follow it. Warships are capable of 30+ kts and would leave any fishing vessel far behind. If China begins building 30+kt fishing vessels then they clearly aren't for fishing and, again, no commander would allow them to follow. There are plenty of ways to shake a tail and, if war is imminent, you sink it. Hey, accidents happen!

    4. " we did in fact have advance indications of many of these "

      ALL OF THEM!

      You might find the following post interesting as regards Pearl Harbor and advance warning of war:
      Battle Order Number One

    5. "But that isn't really any different from actually being caught by surprise, now, is it?"

      Absolutely correct! And that's why we need to rethink our forward deployment because it is quite likely that we won't act ahead of time despite more than adequate warning.

      As far as surprise and the Chinese go, we're already getting plenty of warning that China intends to go to war with us. They're building their military, training up, threatening us, making false territorial claims … in other words, they're laying the groundwork for war. Some day, someone on some blog is going to try to claim we were surprised by the Chinese attack on us that started the war and yet you and I can see it coming today. No surprise. Are we acting on this warning? Not much and not well.

    6. Concerning China, I'm still hoping my theory of Chinese army will need some real practice and some "blooding" holds true before they invade Taiwan or strike USN....that's why I keep my eye on Africa, they sure all moving in fast over there and probably be a good "proving" ground before moving on bigger military endeavor....

  16. I'd like to offer an idea for your next or overnext post. Please, pay attention!!! See there is a problem. US military bases are closely to the chinese mobile or stationary land based cruise subsonic, supersonic and ballistic missile batteries. In the beginning of the war they will fire all the missiles toward the bases. The flight time is at least 15 minutes. The further base is, more time for defense it has, and thus she is safer as not every attack system is able to reach her. Ground based AAW systems are designed to counter the aircraft or high fly missiles. BMD is designed for countering ballistic missiles. And these kinds of missiles are expensive. The numbers or such missiles are less than subsonic, cheaper variants being affordable in large amounts.

    US ground bases lack short range multiple missile air defence systems and radars for countering massive swarms in hundred of missiles.

    The better defense is an offense. But US won't shoot the first. And it shoud defend its bases, facilities and vehicles to save them for counterattacks if they wish to win, not loose.

    And the good defense must be layered, cheaper and in large amounts.

    Why not to use air force F-15/16 or naval F-18 or smth else like UAV (if you don't mind) or aircraft based on the training jets equipped with radar, ISR, optic systems and 2-4 blocks of APWKS 2 of course. Additional they can carry 2 internal fuel tankers to increase their endurance.

    I leave a link below. Even this missile has its disadvantages as the small flight time and range, but they are the cheapest, affordable and massive amounts for defense. Sure it would be not bad to make this missile with larger diameter, length to increase the ranfe od flight and with a newer enfine the speed to Mach 3 also. Or instead of using the APWKS integrate the Stinger missile. It has similar characteristics and might offer the same.

    I want to improve my English knowledge. Sure there's a need leave comments. If you don't mind I stay here for practicing.

  17. COMNAVOPS, I humbly add this link for your perusal. Great stuff, with stats on Aron, armament etc.

    Just adding to the knowledge base here. Of note, I am currently working on figuring out how to fit the Freedom class LCS into their home port, since they won’t be deploying any time soon. Warmest regards.

    1. Yep, NavSource and NavWeaps are two of my go-to sites!

  18. One thing that doesn't get enough mention is armored internal bulkheads. If you take a hit but can prevent the problem from spreading throughout the ship, you are way ahead in the damage control game.

    1. Seriously? I did an entire post on transverse bulkheads! And then cited it in the armor compendium post.

    2. I didn't say it doesn't get enough from you. It doesn't get enough generally. Yours are among the few comments I have seen on the subject.

    3. "One thing that doesn't get enough mention is armored internal bulkheads."

      If you believe there's a lack of general discussion about this then offer a comment with some information. Fill in the gaps for us! Those are the best kinds of comments - ones that further the discussion. So, please, give us some new information and discussion about internal armor! That would be great!


    An article on proceedings calling for armor on ships. (paywalled)


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