Home » Budget Industry » Navy has Found Fix for USS Zumwalt Engineering Problem

Navy has Found Fix for USS Zumwalt Engineering Problem

USS Zumwalt (DDG-1000) passes national historic site Fort McHenry as she departs Maryland Fleet Week and Air Show Baltimore. US Navy Photo

NATIONAL HARBOR, Md. — The Navy has found and tested a fix for an engineering problem that sidelined USS Zumwalt (DDG-1000) several times during the ship’s voyage to its homeport, Zumwalt-class program manager Capt. Kevin Smith said on Tuesday.

During its transit, Zumwalt’s lube oil coolers failed resulting in water leaking into the propulsion system several times – once resulting in loss of power moving through the Panama Canal. The seawater lube oil coolers prevent the lubrication of rotating shafts from breaking down due to heat and friction.

“Like other ship platforms today, when you mix seawater with steel… bad things can happen,” Smith said.

“What we did was shift to fresh water for the coolers. Before we got to San Diego we realized that’s one way of fixing this problem. It’s not a large demand on cooling so we decided to go down that path.”

While the complex electrical propulsion system on the ship was extensively tested pier-side at the General Dynamics Bath Iron Works shipyard, the lube oil cooler problem was only discovered after the ship had spent time underway, Smith said.

The Navy tested the fresh water fix to the coolers during two underway periods the ship has had since it arrived in San Diego in December.

Smith said the periods proved the repair worked and the change has been implemented on the under construction Michael Monsoor (DDG-1001) and Lyndon B. Johnson (DDG-1002).

“As far as ships two and three – and Bath can attest – we’re making sure to make the temporary changes now to make sure we don’t have any issues with the class,” he said.

In the longer term, Naval Sea Systems Command is evaluating a longer-term solution to ships beyond the three-ship class.

“We are looking at next generation, what do we want to do as far as new cooler design,” Smith said.
“Not just for this ship but for other ships in the Navy. There are other things we’re looking at [creating] a better MILSPEC standard cooler that we can put in that will last the lifecycle of the ship – 30 plus years.”

Zumwalt is in San Diego undergoing a maintenance period in which the ship’s combat systems will be activated and tested ahead of a planned first deployment in 2021.

  • Mauvais Garcon

    So, you test an essential component for a sea-going vessel at PIER SIDE, instead of under full load???? Seems legit.

    • Duane

      All new construction ships are tested dockside first, then taken out for sea trials. It’s how it’s done. If there is a serious problem far better to ID it and fix it pierside than out at sea.

      • Mauvais Garcon

        I have NEVER seen a ship test it’s main propulsion plant under full load while tied to the pier.

        • Duane

          I didn’t say full propulsion power dockside. Read again. We test all of the engineering systems dockside before you take her out to sea. It would be dumb to do otherwise. Our Navy isn’t dumb.

          • Mauvais Garcon

            I have worked with the US Navy, a more accurate e description might be that they are not ALWAYS dumb.

        • Niki Ptt

          I did.

          On warships.

          More than once.

          You just have to replace the propeller blades by bracking blades which produce the same resistance as the normal one but little to no thrust.
          And no need for a drydock, you just replace the blades in the water.

        • Niki Ptt

          If you want a well publicized example, you can take the RN
          Type 45s, all of which had their propulsion system tested at full load
          with the same apparatus.
          On a CPP, you just unbolt the normal blades
          and replace them with the test ones. It’s basically a blade foot with 3
          wood logs bolted on it. Whatever the balde pitch, the logs produce in
          fine little to no thrust, but a resistance you can tune finely with the
          pitch to match the propeller curve.
          Basic engineering really.
          the ships with FPPs, we have variable pitch propellers where the pitch
          is set by hand using a good ol’ wrench to match the propeller curve as
          close as possible on its top part, and that does the trick too.
          So no bullshit, just a lack of boat trial engineering knowledge and experience on your side.

  • Strobe

    Water, water everywhere and not a drop to chill my lube oil.


    Salt water > Cooler > Fresh Water > Cooler > Oil Gallery > Cooler > Fresh Water > Cooler > Salt Water?

  • airider

    We’ve used seawater for cooling for decades…hard to believe that this is a unique challenge….and that the solution is to use fresh water?!?!?

    The ocean is a very large “heat sink”. The interesting part of this is that ships designed based on the average temperature of ocean surface water, were unpleasently surprised when they had to work continuously in the Persian Gulf.

    • Shaka_X

      Brits found they had a new class of ships that couldn’t operate in the persian gulf because they would lose power due to the temperature of the water in the gulf

      • Hugh

        RAN had problems there with various H M & E systems too.

      • Niki Ptt

        Yeah, it’s due to the poor design of the heat exchanger for the main turbines. These heat exchangers were designed and built in the US…

  • RunningBear

    ,,,this one sucks!, seawater cooling since the first boat engine (1787), now they will foul the potable water system with lube oil! Shirley they will discover the exotic alloys used in the seawater heat exchangers used on every other boat in every other navy and the ……USN!….WTF??????

    • Kendall Palmer

      Who is Shirley?

      • Eyes open

        From the movie “Airplane” when the pilot says surely but the other guy thinks he said Shirley and he replies “don’t call me Shirley”. It was a pretty dumb movie.

        • E1 Kabong

          Nice beaver.

    • Duane

      It would help if you actually knew something about ship design before commenting on ship design.

    • USNVO

      If your pickup’s lube oil or transmission oil cooler leaks (I am assuming you have pickup with lube oil and transmission coolers, but if you don’t, just run with me on this), does it contaminate your bottled water? Come on, the freshwater cooling system is not connected in anyway to the potable water system. And, since it appears there is an existing freshwater loop that has sufficient capacity to cool the lube oil, this seems like a no brainier fix. If anything, you ask why wasn’t it done sooner (ask yourself how much maintenance you have to do on a cars radiator versus sea water coolers on a boat) since it eliminates the possibility of salt water intrusion in the bearing lube oil.

  • Mike

    Zumwalt is in San Diego undergoing a maintenance period in which the ship’s combat systems will be activated and tested ahead of a planned first deployment in 2021. They just commissioned the beast and it’s already undergoing maintenance and it won’t deploy for another four years. Something is seriously wrong with this ship.

    • sferrin

      That’s what happens when you start/stop the class a dozen times, slash the numbers down to nothing, and then give it specialized everything. The Zumwalts have the potential to be world leading warships but thanks to a series of colossal f–k-ups buy the USN and politicians it’s relegated to white-elephant status. By all rights they should be looking at this hull for the Tico replacement.

      • Niki Ptt

        But you forget Zumwalts were never supposed to be the world leading warships. They are just a gun platform intended for Marines landing support. They are not Aegis ships, and are closer in terms of use of an Iowa than of an Arleigh Burke.

    • Duane

      It’s a first in class developmental vessel. All such vessels, especially those that represent large leaps in technology, suffer issues that have to be corrected. It goes with the turf. Unlike classes of ships developed decades ago, new ship classes, aircraft types, etc. today are subject to incessant chatter and whining from internet armchair admirals and generals who all swear they know far more than the real admirals and generals, just like our current Commander in Chief said all the time during the recent campaign.

      And then reality sets in.

      The armchair admirals and generals nearly always don’t know squat – either they never served themselves in leadership roles bringing in brand new classes of weapons and platforms, or they are simply self-proclaimed internet experts.

      This is a relatively simple problem with a simple solution. The Navy caused the lube oil cooler to be redesigned to isolate it from seawater. In hindsight, it should have been done in the original design, but alas, designers are humans and imperfect beings, just like all human beings. These are incredibly complex machines and perfection, especially for the first-in-class products, is not the standard of performance. It never is.

    • uncaherb

      Way back when, FFG 7 USS O.H. Perry spent it’s first year tied to a pier at D&S Piers in Norfolk. We referred to it as Building 7.

      • NEC338x

        Only a year for a class lead? That would be an improvement!

  • 1coolguy

    First deployment in 2021! Disgusting.

  • The Plague

    “when you mix seawater with steel… bad things can happen” – and this is supposed to be serious communication from a Navy officer? What “target-audience” was that intended for? A bunch of iphone-addicted gen-X/Y/Z college grads with a fresh degree in Makebelieve Engineering?

    • Duane

      The authors dumbed it down for you. Apparently not enough.

      • The Plague

        Now go back to your quarters and reflect for a few more minutes on who’s really dumb here.

    • CHENG1087

      I wonder how ADM Rickover would react to that official USN statement if he were alive today.

      • Western

        If this had happened to one of his submarines, something as basic as a heat exchanger, and non-nuclear at that, heads would be rolling. Engineering officers, shipyard workers, defense contractors, flag officers, the wrath of Rickover would ensure the people responsible would never see or touch anything in the Navy for the rest of their miserable lives.
        A lube oil cooler? Jesus wept.

        • Paul

          USS Thresher, that was a failed joint on a sea water pipe. Sea water causes all sorts of issues for ships, structures and equipment of all types, cooling systems in particular have issues requiring a lot of maintenance effort and on going design work. Remember, this is the first of class of a radical new design, there will be problems and the solutions for them will be identified and implemented.

      • Ruckweiler

        Glad ADM Zumwalt isn’t here to see this engineering and fiscal mess which is this ship.

      • Ed L

        Rickover would had fire the lot of them Rickover was a perfectionist

      • The Plague

        Now that would be a spectacle I would pay for watching..!

    • sferrin

      Don’t mix Gen-X in with the rest of those dumbasses.

      • The Plague

        I stand corrected…

  • Ed L

    I can hear the !MC now. Attention, Due to the use of fresh water for the lube oil coolers, Shower hours are in effect while not at pier side.

    • Ed

      They won’t use the potable water system to cool the lube oil. They’ll have a separate fresh water system for that purpose. The fresh water system, in turn, will be cooled by seawater using a heat exchanger. This type of oil cooling arrangement has been standard engineering practice in ships for years. Why it wasn’t used here was possibly due to an attempt to reduce weight, or space limitations, or money or all three.

      • Ed L

        I am SW qualified with 14 years at sea.6 years unified staff duty and know when an evaporator goes down, they don’t make the Ships system suffer. The Crew makes the sacrifice. The ship systems don’t care if the fresh water is potable or not, as long as it is fresh water. While I haven’t see the Engineering specs for this work of art. I would not be surprise if there were only 2 evaporators on board.

        • Duane

          The freshwater cooling system here would be a closed loop system, not a once-through-and-discharge overboard system. The only need to consume fresh water is to occasionally add makeup water, or to make an occasional adjustment to the chemistry of the fresh cooling water. Given that this system is cooling lube oil, and not used to generate steam in a high temperature boiler, there is no need for “boiler blowdowns” or other large consumptive uses of fresh water.

          Think of this system like your engine coolant system for your car. How often do you have to add water to it, at least in any car manufactured in the last 70 years or so? That system in turn gets cooled by the air via the radiator .. and this shipboard freshwater cooling system in turn gets cooled by a seawater cooled heat exchanger.

        • USNVO

          I am pretty sure it doesn’t have any evaporators onboard at all. It most likely has a couple of RO units that provide all the fresh water that the ship needs and then some far more reliably than evaporators ever could.

  • CHENG1087

    Can we ignore all the snarky comments (including mine) for just a few minutes? There is a serious engineering question here. Every mechanical system the Navy has ever put to sea (with the exception perhaps of Prairie-Masker and a couple other “exotics”) has been lubricated with oil, and that oil has been cooled with sea water in almost all cases. Why are we having these problems now in both the DD-1000 and the LCS? Are the DDG-51s having the same problems? How are the lube oil cooling systems of these two new classes so radically different from every other lube oil cooling system the USN has successfully operated throughout its long history? Where can we old snipes go to get that explanation?

    • Eyes open

      Read my reply above for your answer.

    • old guy

      THIS is the least of its problems. The model of the DD1000 capsized during tests in the DTNSRDC turning basin. It would be better if we could load Congress into the bilges, as ballast.

      • Duane

        You model obviously didn’t include sufficient ballast. Virtually all ships require ballast to avoid flopping over, and the DDG-1000 is far less top heavy than many other designs afloat today. It was tested fully in sea trials and, sorry to disappoint you, it didn’t flop over.

        • old guy

          No, Duane, All models are properly scaled, dimensionally and displacement. The problem with DD1000 is the “tumblehome hull design which reduces the righting moment with roll angle, rather than increasing it.

          • Duane

            I’m saying your models were poorly designed. The DDG-1000 doesn’t flop.

            Tumblehome has been used in warship design going back 400 years to the Elizabethan era. All it takes is sufficient ballast. Tumblehome was the only way to make double and triple decker warships stable. It worked then, it works now. All you need is ballast..

            Heck how do you think those grossly topheavy super cruise ships stay upright? Through extensive active ballast management systems.

          • Niki Ptt

            Well, concerning the cruise ships, not really…

            They have an initial GM of around 0.5m (which is close to the regulations minimum), and rely on their very wide hull(L/B down to 5, for a breadth of around 60m) for stability. The ballast system is not actively managed, but they have Flumes and stabilisation fins.

          • old guy

            Sorry it took so long to get back to you BUT
            1. All models are Froude scaled.
            2 All models have correct ballasting to accurately portray Kg and rolling moment.
            3. The sHAPE of an old sailing ship and its MUCH greater ballast requirement, to counter high sail loads, and rounded bottoms makes tumblehome irrelevant, but in a virtually flat-bottomed ship, it becomes critical.
            Con la vente a su popa.

      • Paul

        Several years back while attending a marine surveying course run by ABS this very indecent came up. Turns out it was during extension testing where a very large (think tsunami) was pushed up the stern of the model. With that data in hand the design was modified to mitigate even that incredibly unlike risk, which of course is precisely what tank testing is for.

        • USNVO

          You mean they actually do model tests to determine the limits of safety on the ships and then make adjustments and not just to have fun with models? I read one poster think that the DDG-1000 would be unsafe beyond Sea State 4 because they did computer testing of the generic hull form and compared it to a similiar displacement DDG-51 hull form and found that at similiar KG, the ultimate stability was less at Sea State 8. Which was even more hilarious because the paper clearly listed that the objective of the simulation was to explore the impacts of changing KG on stability of the various hull forms and that none of the series were actual ships. So even though the actual DDG-1000 displacement was 50pct greater than that used in the simulation, the L/B ratio was different from the model, he didn’t know what the actual KG range was, or even that Sea State is not a linear measurement, he insisted that it was proof the ship was unsafe beyond Sea State 4.

          • Niki Ptt

            I think you got your poster from the blog of the infamous Mr Park McGraw… Who is by the way a fraud! ^^

  • Michael D. Woods

    It looks rather delicate. What will happen if it takes battle damage?

  • Larry Dicks

    maybe we should do a shake down cruise off North Korea

  • Eyes open

    Having sold heat exchangers my entire career, I can say that they are probably using flat plate heat exchangers which are stamped sheets of metal that are sandwiched together with long studs. If these are leaking, allowing salt water into the lube oil, FIX THE DAMN HEAT EXCHANGERS!!!! Before the flat plated style heat exchangers became the new technology, these exchangers were welded shell and tube heat exchangers. This type is not serviceable, like the flat plate style.

    • KillerClownfromOuterspace

      I’ve been noticing the HO/LO heat exchanger failures in all classes. LPD17, LCS now here. I’m pretty sure they were all not flat plate. Given that, any idea what’s causing it?

      • Eyes open

        I only know the two kinds I have mentioned. Both could leak from the water side to the oil side but shell and tube experienced fewer failures since they were welded together. But if any heat exchanger is not made of materials that salt water will not attack (like cupro nickel) the salt water will eat through rather quickly. Back in the late ’60s, the WW II carrier that I was stationed on finally got air conditioning for our berthing compartment. It ran for three months then died because the manufacturer used carbon steel on the shell and tube heat exchanger (condenser in this application) so the salt water ate through and dumped salt water into the refrigerant side of the system. They still weren’t fixed when I was discharged two months later.

  • disqus_89uuCprLIv

    Seems to be time to look into the research the Merchant Shipping Community’s Industrial partners have accomplished in using water to cool shafts (given however, that Mership propellers and shafts turn slower than warship screws do) along with lube oils which are not harmful to the ocean environment.

    This problem has become an achille’s heel for the Zumwalt. Now NAVSEA has to figure out how to ensure cooling water gets to the shafts as well as to the weapons and surveillance systems. In areas of the world where seawater inlet temps are in the 80s (f) and temps in the 90s are not uncommon, exchanging heat into the sea might not be adequate (regardless of whether the exhange is for direct lube oil cooling or for the ship’s chilled water system.) Greater capacity will be necessary and that will require mods to the ship’s systems.

  • seamarshal

    Despite the fix, what now is going to happen to the former Captain that was canned because of loss in faith of his leadership? Typical, if you can’t fix the problem blame the Captain even though he couldn’t have fixed it even if he knew what to do. Navy is till sailing toward the rocky shores!

    • USNVO

      Well, first since the CO was not relieved for cause, I am sure they will just let him go to his next duty station. Captain Kirk was relieved as previously scheduled (He was CO for over 3 years) on December 20th. Given that SURFFOR was the guest speaker and he spoke well of the captain and crew, I am pretty sure he wasn’t fired.

  • dog lover

    Still using fossil fuels. In time of war maybe you’ll start realizing the benefits of nuclear propulsion. So cave man it’s scary.

    • NEC338x

      The contractors can’t seem to keep NaCl out of lube oil. You think we can expect them to somehow do better with primary coolant?

    • Niki Ptt

      Oh, we can consider, the problem is presenting the price tag to the tax payers… This part is always tricky.

    • old guy

      I’ with you, kid!

  • old guy

    The best solution for “Old Flopover” is to con the Coast Guard into believing that it could be the “Super L.E.C.

  • J. Neville Groff

    Any recreational power boater knows a freshwater isolated system is far more reliable and longer lived than seawater cooling.

  • Kino C

    Just make sure you guys build a “stealth” tug boat to follow this ship into battle. You’ll need it.

    • old guy

      More ballast and make it the new presidential yacht. Prez Trump might even fund it, personally.

  • old guy

    The only REAL fix for the DD-1000 is to jack up the rudder post and design a new ship ahead of it.

  • old guy

    I listened to VADM Tom Moore, COMNAVSEA, the other day and if his thinking can overcome the lobbyists, we might get a more balanced view of maintenance and SLEP (easy to predict cost, fairly accurately) and new construction (buy-ins and runaway changes). We can only hope.

  • Malakie

    Were I able to still serve, I would have definitely requested to be stationed on one of these ships. Seems like most are thinking inside the box, old school Navy design from what I am reading of posts here.

    When it comes to this kind of new technology and capability, you have to think outside the box.. the capabilities of this class once any bugs are worked out (which happens with ALL, repeat ALL major first of class military systems whether ships, aircraft or other), this ship will be the tip of the spear without match or equal.

    Serving on one of these would be an awesome ride.