Monday, November 7, 2016

Damaged LCS, Damaged Again, Damaged Yet Again !!!

You recall the recent post about the damaged LCS (two engineering failures within 24 hours), USS Montgomery, LCS-8, being damaged again (hull crack from banging into a tug - see, "Damaged LCS Damaged Again")?  Well, astoundingly, it’s been damaged yet again.  The ship ran into a wall in the Panama Canal and suffered a foot and half long hull crack.

My concern with these events is the flimsy strength of the hull being exhibited by the LCS-2 variant.  The ship bumps into a tug (isn’t that what tugs do?) and suffers a hull crack.  The ship bumps into a lock wall (not the first ship to do that!) and suffers a hull crack.  What does this say about the class’ ability to absorb battle damage?  I could understand dented hull plating but actual hull cracks from nothing more than “routine” bumps?  What’s going to happen when the ship bumps into an anti-ship missile?

How's that aluminum construction working out?

If the Montgomery doesn't stop bumping into things it's going to fall apart from all the cracks.

I’ve received consistent, though officially unverifiable, reports of the lightness of construction of these ships and every incident like this just serves to confirm those reports.

This is what we consider a "warship"?

This does not bode well.



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“USNI News website, “Littoral Combat Ship USS Montgomery Damaged Transiting Panama Canal”, Sam LaGrone, 31-Oct-2016,


8 comments:

  1. Most likely they were not built to absorb battle damage. Didn't they have strong contact points for tugs to hit built in?

    However on the positive side missiles that hit them will probably not detonate but fly straight through one side and out the other without contacting anything firm enough to set them off

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  2. Make work program for the Heliarc welders union. What a shame!

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  3. is assignment to these ships a form of punishment for sailors?

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  4. Collision with a reinforced canal wall will damage any ship. My first ship (an FF 1052) collided with the canal wall due to port handling of the ship by the embarked canal pilot. The sonar dome was ruptured and several other compartments flooded. All this took place at relatively show speeds, but when thousands of tons of mass are involved, even steel hulls give way.

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    1. My point and concern is not with a single incident. I'm concerned that we may be seeing a pattern of cracking due to relatively minor "bumps". Consider the pattern:

      -The Freedom suffered extensive cracking throughout the ship just due to normal sailing.
      -Montgomery suffered a hull/weld crack due to a "bump" from a tug.
      -Montgomery suffered a hull crack from hitting the canal wall.

      We have no data on the speeds at impact for the "bumps". The canal/tug contacts may have been hugely excessive and the resulting cracks may be a testament to the strength of the LCS. On the other hand, the contacts may have been minor and the cracks may be a testament to very lightly constructed ships.

      I'm seeing the beginnings of a pattern of fragility. We'll wait to see how the ships hold up over time but the data we have concerns me.

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    2. Freedom's cracks were diagnosed as poor quality welds. Marinette put $150m into their shipyard infrastructure in order to correct such issues. They do not appear to have continued on Fort Worth or on Milwaukee.

      The odd shape of the LCS 2 variant may be the cause behind damage from tug and canal wall impact. Having several hundred tons of weight times the force of the tug impact on some oddly shaped part of the LCS-2 hull (and there are a lot of those on a Trimaran) may have been enough to crack a weld. Austal may also have some bad welding issues as did Marinette.

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    3. I have a copy of the "Crack Monitoring Survey During Rough Waters Trial Period #2" by the Structures and Composites Division (Code 65), Naval Surface Warfare Center, Feb 2011. The report lists 17 cracks along with a description and photo of each one. Only two are directly in/on a weld. The rest are freestanding although one or two additional are in the vicinity of welds though not, apparently, part of, or connected to the welds (tough not to be near a weld on a ship!). So, 15 of the 17 documented cracks do not appear to have been weld related. Objectively, even the two cracks that were in welds may have been co-incidental locations rather than caused by faulty welds. Given the prevalence of cracks, I'm inclined to believe that the two cracks were not weld defects but that's just speculation on my part.

      There may have been other cracks that were weld related and were not the subject of this report but, if so, I'm unaware of them.

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  5. Just scrap the whole class already. This is what you call sunk cost fallacy.

    Or maybe keep them as museum ships. All future naval architects should be required to visit these ships to understand how NOT to design a ship.

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