Saturday, June 16, 2018

Battle Damage Design Lessons

I’d like to look critically at the recent Burke collisions and damage as they relate to warship design.  Because sailors died, I hesitated and thought long and hard about whether to do this or not as it might seem to some as being critical or disrespectful of the dead.  In the end, however, the lessons that can be learned outweigh any sensitivities and I would hope the dead would want us to learn from what happened.

ComNavOps has consistently preached that the Navy has forgotten what war is and how to design a ship for war.  In addition to weapons, sensors, armor, and the like, the Navy has forgotten how to build a ship that can sustain damage and has a maximal chance of recovery for the ship and the crew.  The recent McCain and Fitzgerald collision reports (Nov 2017 Memorandum and Enclosures – ref (1)) offer graphic evidence of this design deficiency and lessons that ought to be learned.  Specifically, let’s look at the problem of debris after the collisions.  Consider these statements from the report.

“Racks and lockers detached from the walls and were thrown about, leaving jagged metal throughout the space. Cables and debris hung from the ceiling.” (p. 53)

“Debris, including mattresses, furniture, an exercise bicycle, and wall lockers, floated into the aisles between racks in Berthing 2, impeding Sailors’ ability to get down from their racks and their ability to exit the space.” (p. 14)

“One Sailor reported that FC1 Rehm pushed him out from under a falling locker.” (p. 15)

“Exiting from the head during this flood of water was difficult and required climbing over debris.” (p. 15)

“Lockers were floating past him and he scrambled across them towards the main berthing area. At one point he was pinned between the lockers and the ceiling of Berthing 2, …” (p. 15)

“Even after the door was open, there was a large amount of debris and furniture against the door, preventing anyone from entering or exiting easily.” (p. 18)

“The passageway leading to the ladder-well was blocked by debris, wires and other wreckage hanging from the overhead.” (p. 52)

“Sailors had to climb over lockers and other debris to escape, … “ (p. 53)

“…a number of lockers that became dislodged during the collision.” (p. 54)


These statements paint a graphic picture of a nightmare maze of debris in the affected compartments.  The debris impeded escape efforts and subsequent search and rescue efforts. 

Let’s be clear …  when a ship is hit by an explosion or collides with another ship there will be debris and lots of it.  It’s unavoidable.  Structural elements such as walls, doors, overheads, cable runs, etc. will be ripped apart and torn free from their mountings.  Nothing can prevent that. 

What can be prevented is the presence of loose debris that was never secured.

What can be minimized is the presence of debris that was never strongly secured to begin with.

What can be minimized is the presence of debris that served no warfighting purpose to begin with.

Let’s take a closer look at debris that served no warfighting purpose to begin with.  This would be just what it says and would include TVs, video games, exercise bikes, couches, personal gear beyond that necessary for shipboard duty, etc.  I can already hear the sound of keyboards being furiously bashed upon as people pound out replies telling me that without some comforts, no one will volunteer to join the Navy and serve aboard ship.  We already addressed that, in depth, (see, “Crew Comfort”) but we’ll briefly review it.

First, I’m not saying that all creature comforts should be banned from ships.  I’m saying that they should be severely minimized and modified.

Second, we have to recognize that the reason we have ships and crews is to fight and we have to be ready to fight with no notice.  Stripping ship is a tradition when a ship knows that it is going to be in a fight so, if that’s a wise thing to do when combat is imminent, why should it be different just because the ship doesn’t know when it will have to fight for its life?  We’ve seen that life and death situations can arise at any moment:  the Cole attack while in port, the Port Royal grounding, the Enterprise and Forrestal conflagrations, mine strikes, the missile attacks on the Burke destroyers off Yemen, and the recent collisions and groundings.  Today, there is no such thing as peace and safety at sea.

Third, we should ask why we feel we need creature comforts?  The answer is obvious – we need them because we send ships and crews on deployments that are far too long.  I’ve already addressed this and recommended that we abandon deployments in favor of missions (see, “Deployments or Missions?”).  Failing this, we need to reduce deployments to 2-4 months.  The problem is that we’ve done the exact opposite and gradually increased deployments to 8-12 months.  We need to regain some deployment rationality.  If we do that, we can live without as many comforts for reasonably short periods.

Let’s consider debris that was never secured or not strongly secured to begin with.  Chairs, exercise bikes, couches, mirrors, and a hundred other items all need to be securely fastened.  By “securely”, I mean fastened with ten times overkill.  Fastened beyond any reasonable degree because an explosion or collision is not a reasonable scenario.  Therefore, we have to prepare for the unreasonable.  If that means a little less ease of use or flexibility in placement then so be it.  That’s the price of survival.

Here’s a few more specific recommendations related to crew comforts and survivability:

  • Lockers, furniture, etc. should not float; they should be designed to sink.  It’s easier to scramble over something on the deck than try to fight past something floating right in your way.
  • Locker size should be minimized.  This ties in to minimizing unnecessary personal items.
  • Nothing should be unsecured (exercise bikes, TVs, consoles, tables, etc.)
  • Everything should be secured far more than is deemed necessary or reasonable.
  • Lightly secured items should be as far inboard and as far from exits as possible
  • Thought should be given to making lockers and berths out of rigid plastics instead of sheet metal which, when ripped and distorted, presents edges as sharp and lethal as knife blades.  This has to be tempered by the fact that most plastics give off toxic fumes when burned.  This is a recommendation that needs study and may or may not be desirable.
  • Thought should be given to making large items such as lockers pre-designed to fail and separate into small sections.  Thus, rather than tear an entire locker loose and present a major obstacle, smaller, breakaway sections can be produced while the larger potions remain secured as they originally were.  Alternatively, but along the same line of thought, lockers can be designed as small, modular components which can separate independently from their mounts, hopefully leaving more of the overall item secured.  Worse case, the smaller sections would be easier to move out of the way for escape and rescue.


Here’s an interesting though unrelated item.

“FITZGERALD also used three onboard pumps to remove water from the ship. Two of the pumps functioned as designed and a third seized and was inoperable for the duration of the recovery efforts.” (p. 11)

Clearly, the inspection and verification of operation procedures for these items was deficient.  Instead of spending time sitting through another gender sensitivity meeting or filling out another sexual harassment survey, maybe we should be spending our time inspecting and operating vital equipment?

We have forgotten what war is and hand-in-hand with that we’ve forgotten how to design ships for combat and damage.  Let’s not waste the lessons from McCain and Fitzgerald.  They cost us too much to ignore them.



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(1)Department of the Navy,  Memorandum for Distribution, Enclosure (1) Report on the Collision between USS FITZGERALD (DDG 62) and Motor Vessel ACX CRYSTAL, Enclosure (2) Report on the Collision between USS JOHN S MCCAIN (DDG 56) and Motor Vessel ALNIC MC, Nov 2017



17 comments:

  1. Plastics can also create sharp edges when broken and can also float creating the hazards as described in the article.

    On the inoperable pump, I haven't read the report, but is it possible the pump injested some FOD generated from the collision?

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    1. "is it possible the pump injested some FOD generated from the collision?"

      I have no idea but if that did occur then the pump is a poor design for the purpose. In any flooding situation, the water being pumped will contain debris and the pump should be designed to deal with it (intake screen?). Maybe someone with better knowledge of these pumps can enlighten us?

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  2. This might be a little bit off topic, but are they any navy departments who are supposed to test and think about that kind of stuff?

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    1. There was ... once. It was BuShips but it's gone now. There are probably a few specific pockets of limited responsibility but, no, there is no department tasked with this type of responsibility, to the best of my knowledge. And, if there is, they're not doing their job.

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  3. Very astute points. We never had this sort of problem (well, not in well run ships) in the "Old" (1980s!) Navy. Lockers were in the racks, exercise stuff was in the "Gym" (If there was one), and everything else was pretty securely bolted down to the deck or bulkhead. The first good roll underway usually sorted out who had not done their job in securing for sea.

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    1. Do you have any suggestions for better ways to construct or arrange racks and lockers?

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    2. Racks need to be with integral lockers and well fastened to the deck and bulkheads for crew spaces. Transom bunks, also well fastened for CPO and officers. Any other appurtenances (e.g.bulkhead/standing lockers) must be fastened to the deck AND bulkhead securely--angle irons are a good way to do this.Collateral, especially unofficial additions must be rigorously controlled (inspections daily hint hint)and ruthlessly suppressed (This is what XOs used to be for). Stainless steel is the way to go for construction and fastening material. It goes (I trust) without saying that all compartments must be policed for loose/unsecured gear regularly (Remember lucky bags?)and trash collected and emptied regularly. I suspect that plastic is not, at least for now, viable because of toxic fume and other considerations, though sturdy fiberglass for some applications might be.
      "Personalizing" spaces, however attractive to imagined morale considerations, must be controlled within the foregoing strictures. NAVSEA (Who really in its little steel heart never stopped being BuShips) has good published guidance on all this, that guidance just needs to be read, understood and followed.
      I get it that Burkes are more stable than Adams DDGs; but the sea is an unforgiving mistress--prepare for her worst (not what you've experienced or expect) or you are in peril--and your people too through your own negligence.

      OK. Old Salt rant off-- but I meant every word.

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    3. Captain Steve, excellent comment and thanks for sharing your thoughts on this. You seem to have much more of a combat readiness mentality than is typical today and I heartily approve!

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  4. Read the report on the sinking of HMS Sheffield, pumps and generators not working.
    That was a ship on it's way to a war zone.

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    1. In a war zone having been in transit for some time.

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    2. The Sheffield Captain (Salt)was a career submariner and his XO was a helicopter officer, both with little surface ship experience. The 2 senior officers in the Ops room were found negligent by the enquiry but not court martialed.

      Its different but similar to the issues raised by CNO here for the 7th fleet destroyers.

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  5. I wonder (never served in the Navy) if these long deployments create? an insidious, creeping mentality that this is NOT a warship but some-kind of low grade cruise ship that just happens to have some weapons onboard (that never get used or trained on...)

    CNO always brings up we should have MISSIONS and not long deployments/cruises and I've started to wonder if one consequence of these long deployments with little to no action, what kind of real military training gets done?, the people onboard are naturally NOT prepared, everything becomes routine!

    I understand there should be some creature comforts and training gear, what I'm talking about is the MINDSET that let the situation get to the point that not 1 but 2 US Navy ships collided with civilian ships and the crews had to fight thru their own debris to get to safety!...forget that these ships were probably damaged to the point they were mission killed, that's another topic....

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    1. "an insidious, creeping mentality that this is NOT a warship but some-kind of low grade cruise ship"

      Excellent! I think you're spot on.

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  6. Part of the problem is the Burke stability. My first ship was a Adams Class Destroyer which was notorious for rolling badly in any seas. So we tied down everything My next two ships were more stable and my last ship was a Burke. I was Divisional LPO and so when we got underway the first time I went around the Division spaces and made sure everything was tied down. The more junior enlisted in my Division who had been underway many times looked at this strangely. When we got underway the ships was very stable even when we hit bad weather and much of my effort was not needed.


    As to securing things better the racks are pretty secure and I don't think anything could stop their movement once the ship is hit and the side of the ship is pushed in which will then move the racks

    The smaller lockers on the other hand are not secured very well and mostly held by angle iron which are tack welded to the bulkheads and frames and have 1/4 20 nuts and bolts holding the lockers to the angle iron. 1/2 20 nuts and bolts are small and often have small or no washers which means that under pressure they can be pulled through the thin sheet metal of the Aluminum sides of the locker. So larger bolts with larger Washers would help, along with frames made from something stronger then angle iron tack welded in place

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    1. Oops it should read 1/4 20 not 1/2 20. A half inch nut and bolt would work much better

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    2. Great comment and thanks for that insight. Do you have any other ideas about better securing against debris? Could lockers be built into/onto the structure of the compartment? Welded, as opposed to nut/bolt? Maybe horizontal lockers integrated into the base of each rack as opposed to external, stand alone?

      What do you think of the level of flammables on a Burke? Fire did not occur in the recent collisions but that's always a concern in battle damage.

      If you were desigining the berthing spaces, what would you do differently, as regards damage mitigation and survivability?

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  7. Present day ships like the Burkes have coffin racks, that is the rack has a locker under the mattress where you lift up the top plate and access a large area. Usually you will often have each rack getting a stand up locker near your rack which is often used for dress uniforms and shoes. Some of the top racks don't get a coffin rack since there is piping or vents above which does not allow a coffin rack, they will often get two or three smaller lockers.

    The set up for the racks are a mattress, a sheet over the mattress, a pillow at the head end, a folded blanket at the foot end and I often had a spare sheet also folded over the blanket.

    The problem for this is that all these items are loose and can end up being debris. I have seen pictures of some ships where they have two straps which hold down the pillow and blanket ends preventing them from floating away. This does not help much at night but during the day it would help with damage control.

    Another item that is useful for debris is a small bag about the size of a gym bag which is issued to each rack and straps onto the rack where small personnel items can be kept while at the same time controlling their movement. I don’t remember what they are called but they were Navy issued items. However not all ships are issued them

    One big problem is getting the ships to follow and use these items. One time where it is easy is during morning inspection of berthing by the XO, however it might be helpful to have another inspection at Taps and have someone like the Command Master Chief walk through the berthing and make sure that items are secure. That way the crew would understand it’s a command priority

    Another thing that can turn into debis is the crews uniforms when they go to sleep, The crew sleep in their underware and hang their uniforms on the outside of their racks so they are ready for use in case of Watch or GQ. The crew is not allowed to sleep in their uniforms. So some arrangement of a place their present uniforms and boots securely would be useful in preventing these uniforms becoming debris

    You might say why not put the uniforms inside the lockers when you sleep but for example my lockers were pretty full of extra stuff due to being on a long deployment where I might not be able to get a new uniform or other item I needed. The ships do have a ships store but selection is limited.

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