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Thursday, October 6, 2016

Damaged LCS Damaged Again

This could only happen to the poor LCS program.  The USS Montgomery (LCS-8), already in port in Mayport for repairs after suffering two engineering casualties in 24 hours in mid-September, took a “knock” from a tug as it was putting to sea ahead of an expected hurricane and suffered a 1 ft x 1/4 inch crack along a weld seam as well as some bent stringers (horizontal hull structural beams) (1)

My issue with this incident is the physical weakness demonstrated by the ship as a result of what appears to have been a fairly mild contact with a tug.  What does this say about the LCS’ ability to absorb actual battle damage?  The Navy has stated that the LCS was only designed to stay afloat long enough after a hit to allow the crew to escape.  Of course, I’m ignoring the fact that the Navy has also claimed that the LCS was built to Level 1+ (Level 2 except for one or two minor requirements) standards which means that the ship should be able to take a hit and keep fighting so there’s an inherent contradiction but, I digress …

This lightness of construction is not limited to the LCS.  We’ve seen that the Aegis cruiser, Port Royal, was severely or permanently damaged by nosing gently aground.

The Burkes were found to have been too lightly built and have had to have reinforcing plates added to the hull.

I’ve commented on the Navy’s tendency over the last few decades to build ships far too weak, physically.  I won’t belabor the point.  This is just more evidence that the Navy has forgotten how to build warships.



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(1)Navy Times website, “Tug Collides With LCS Montgomery, Cracks The Hull”, David B. Larter, 6-Oct-2016,

23 comments:

  1. It cannot absorb damage, not much anyways. It's more like a commercial vessel.

    How long will this thing last against a USS Cole style suicide motorboat attack?

    Something like a Gearing-class destroyer would be a better decision.
    If it ends up in a conventional war ... the aluminum superstructure will burn.

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  2. The USN makes a big deal about lots of rowing boats swarming their ships, but it looks like you could get a handful of guys to scuba dive with spearguns, shoot the spears at the hull, and badly disable the LCS. Am I wrong? Did I just hand Iran the key to silently sinking 15% of the USN fleet? Just head down to the local Surf, Dive and Ski shop!

    A

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  3. If the HVS2-Swift (the LCS predecessor) gives any indications of potential survivability, it has either survived 4 RPG hits or a direct hit from an anti-ship missile and currently is heading to a friendly port for repair. The pictures are located on google, and the damage looks extensive thou mostly fire related.

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    1. I have refrained from commenting on this incident due to the almost complete lack of accurate information.

      Do you have any actual facts to support your statement about the source of damage or are you just speculating like everyone else?

      Delete
    2. I think we can actually predict that due to the damage absorbed the ship is scrap now

      That will be the same fate the LCS will suffer if struck by similar missiles or missile

      FYI rpg had a much smaller warhead than a anti ship missile. I would be aghast to think a ship could suffer that much damage from about 5 pounds of explosives

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    3. I found these.

      https://www.workboat.com/news/bluewater/hsv-2-swift-wrecked-yemen-missile-attack/


      http://www.themercury.com.au/news/tasmania/yemeni-forces-sink-incat-vessel-hsv2-swift-which-was-carrying-supplies-for-uae-forces/news-story/2e5023cebd3a0a6a83ac6ff077741c53


      I can't speak to the authenticity of the articles.

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    4. I have no facts except what everyone else has heard. That said, I felt it prudent to point out to anon, that a similar constructed vessel has survived a direct attack and remained afloat.

      I will now wait, until you publish an article on this, before I make any further comments on this. Undoubtedly, it will be an informative piece with much insight.

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    5. I have no plans for a post on the attack on the HSV. There is no authoritative information on which to base a post. I've variously read that the attack sank/did not sink the ship (photos indicate that it did not), was an RPG, was several RPGs, was an anti-tank missile, was an anti-ship missile, was a C-802 missile, the HSV was armed, the HSV was unarmed, the HSV was carrying relief supplies, the HSV was carrying military supplies, the HSV launched land attack rockets/missiles, and so on. There is not a single piece of corroborated information beyond that apparent fact that an attack occurred.

      With absolutely no definitive information, there is nothing for me to comment on that I have not said in previous posts about ship construction, in general. If additional information comes out, I'll reconsider.

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    6. Whatever hit it, killed it.
      You can't say most of the damage was fire related and leave it as a maybe.
      It took a hit, couldn't deal with the consequences, and burnt to the water line.
      So, based on this pic, it can't take damage and survive.
      If its goal was to just float so the crew can jump overboard, then yeah, it worked...

      Delete
    7. "It took a hit, couldn't deal with the consequences"

      This is exactly why I'm not doing a post of this - we just don't have any useful information. What size was the crew? Were they military or civilian? Were they even trained for damage control? Was any damage control attempted? You could start a trash fire in a garbage can and burn the ship to the waterline if no damage control is performed. Was there any automated fire suppression system? And so on. To try to draw any conclusions is irresponsible.

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    8. Well, at least there is another baseline: the burke is capable of defending against hi-subsonic ASM, as designed, as expected, and as should be. Still, I'm sure it's not fun waiting out the expected missile knock down, inside the control room. Hi-fives and champagne spray?

      Delete
  4. Yeah, and the EPF needed structural bolstering, and the NSC Cutter needed millions in structural support (that still may reduce the ship's operational life in hours per year), and we didn't resolve the DDG-51 issues until about 40 DDG-51s were built. You'd think that fun and pricey standards-making experiments like ABS NVR would have helped, right?

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  5. To be fair, Port Royal didn't just nose gently aground -- it got hung up and surf bounced it against the reef for days.

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    1. To be fair, it nosed gently aground at about 2 kts and rocked gently until it was freed.

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  6. I realize this may be apples and oranges, but USS San Francisco hit a seamount at flank speed at 500ft and (barely, I guess) was able to be surface and be recovered, without suffering a reactor casualty.

    Thats a heck of a shock to a vessel with very sensitive electronics supporting very critical (no pun intended) things like the reactor; but they were able to maintain power and surface after losing a significant portion of their forward ballast tanks.

    I know that subs are different and significantly more expensive, but this durability speaks to just sound basic construction practices too.

    Are we not using those in the surface fleet? Are they considered too costly/superfluous?

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  7. The denting of the hull to absorb the energy of the collision doesn't concern me as much as the crack.
    The cracking of the weld calls into question material and weld quality as well as the weld procedure.

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  8. You may wish to consider the strength required to resist simple water pressure (plus shock load) at several hundred feet depth, versus the need to resist surface hydrostatic loads (including wave induced bending moments). They're very different and result in very different styles of construction - which is why the structural design criteria for surface ships and submarines are very different.

    Swift is not an analogy to LCS. It was a commercial design Incat catamaran with one or two military add-ons - none of which were to do with its ability to resist damage. The ability of a ship to resist that sort of damage is primarily driven by its internal arrangement and bulkhead design, rather than the shell construction. Having actually set foot on HSV2 as she was then, I can confirm she was a ferry with a C2 space, extra berthing, a flightdeck and a ramp. Nothing like a warship.

    Damage from tugs is not an unknown phenomenon for steel warships. You should also note that commercial ships - which usually are built from thicker steel - have specific tug hard points to deal with the local loads. You can usually see them painted on the hull - they're marked "tug".

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    1. "Swift is not an analogy to LCS"

      Swift is not all that far from the LCS-2 version. The LCS-2 was adapated from a commercial ferry design and, initially, built to commercial standards. Later, some semi-military standards were applied but I've never seen a comprehensive list of what military standards were applied. The fact that it demonstrably does not meet even Level 1 survivability standards suggests that it is much more commercial than military. So, LCS-2 is an adapted commercial design with some military "stuff" added on - likely not all that far from Swift.

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  9. Hmm. Perhaps you'd care to list those "commercial standards"? Or indeed identify the differences between Fred Olsens ferry and what was designed by BIW and built by Austal?

    Maybe you could also list the "semi-military" standards applied and explain why they are "semi" as opposed to "military? That would (of course) provide a factual and logical back-up to your statements.

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    1. I'm pretty sure you're looking for an argument rather than a learning discussion but on the off chance that I'm wrong, I'll give you an answer.

      First, I expect that readers will have a certain level of background knowledge to participate in this blog. I expect that higher standard from my readers. Therefore, something as thoroughly documented in the public domain as the LCS is something you can research on your own. The LCS was initially designed to commercial standards. That's readily verifiable. Those standards are also readily available on line.

      Later LCSs were built to semi-military standards. Again, something you can research on your own.

      There were many aspects of standard Navy warship construction that were omitted from the LCS such as shock hardening of individual components, emissions control capability in individual components, sufficient compartmentalization to enhance survivability, sub-Level 1 survivability standards, less than Navy standard weight growth margins (documented by DOT&E), less than Navy standard stability margins (documented by DOT&E), and so on. This is more than enough to both establish the validity of my statement and give you the leads you need to research further on your own.

      There are many good avenues for further discussion from this:

      -how will the non-standard stability margins affect survivability?
      -how will overall sub-standard survivability of the class impact the class effectiveness and usefulness in combat?
      -is the use of aluminum justified given the repeated examples we see of the catastrophic results of aluminum in fires?
      -are commercial construction standards viable in vessels intended for combat?
      -and so on ...

      If you're interested in a learning discussion, feel free to reply. If you're looking to argue for argument's sake, don't bother - I'm not interested and won't allow it.

      One final point for your consideration is that this is a blog not a textbook. Further, comments are limited to a paragraph or so. The point is that the degree of documentation that can be provided is quite limited due to the space limitations. I provide references for facts that are not common knowledge and are central to the premise of the post. Other statements are offered without documentation due to the space limitations. Rest assured that those statements are factual. If you do not believe them, the onus is on you to verify them. I have neither the desire nor the requirement to prove every statement to your satisfaction. If you do not believe my statements and my demonstrated body of work and do not wish to do your own research to assure yourself of their veracity then you should probably consider finding another blog more to your liking and trust.

      Delete
  10. So you're suggesting that USS Independence was built to GL High-Speed Craft Ro-Ro ferry notation? Which is what "commercial standards" - or at least those for Fred Olsens trimaran - actually means. I should have thought at the very least ABS would have been used as the Class society, which it was - and for LCS1 Freedom as well. Except both ships were built under the ABS Rules for Naval Vessels. Which are not commercial standards - although they are derived from them, they do apply military required design factors. HSV2 Swift was classed by DNV under their commercial High Speed Light Craft Rules. Again - a true commercial standard, not a naval standard and not an approximation to LCS.

    Care is required in using the phrase "commercial standards". They are not always what those who are not maritime professionals believe they are. I'm personally far from an LCS fanboy. However, where incorrect assertions are being made - a learning discussion ought to identify them, explain the discrepancy and correct them.

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    1. Good, you've done some research. Now consider this quote from Adm. Sullivan during Congressional testimony.

      "Because they [ABS] worked with us on the Naval Vessel Rules and because we had several rounds of discussion of those rules and several rounds of publication of those rules, we felt that their [the LCS] design reflected the rules. It was only in that seven-month period that you are talking about that we discovered we
      were--the ship that was bid did not include many of the
      provisions of the Naval Vessel Rules because it was based on a commercial design and in getting the ship design from the commercial design to meet the rules that we need to keep our sailors safe, that is what took those seven months, and again, because of the highly pressurized schedule, the ship construction started before the design was complete."

      This clearly indicates that the LCS design was commercial based and initially constructed under commercial rules. The NVR set (a combination of commercial rules and naval adaptations) was applied later. Further, modifications were made to the LCS which modified or eliminated some of the NVR requirements.

      The development of the LCS design requirements is a fascinating topic though far too technical for a blog post.

      Delete
  11. Selective quotes from a congressional testimony, while counting as research, doesn't necessarily cover the actualite.

    What he is saying is that there were aspects of the design that needed revision (these might be arrangement, might be structural, might be systems - we don't know) and some construction started before that 7 month process was complete. If you know how ships are built, that's not the same as saying the ship was built to commercial standards and then modified, and certainly not "later ships built to semi-military" standards. The key is entirely in the notations applied. Some requirements to achieve commercial standard notations are actually in excess of naval requirements.

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