This episode we're talking about some specific issues in the Iowa Class engineering plants. To send Ryan a message on Facebook: / ryanszimanski To support the battleship's efforts to drydock, go to: 63691.blackbau...
We did a full power run before Captain Katz left with all 8 boilers and all four engines had the RPM needle go past zero. We did this off the coast of San Diego going towards Long Beach and we were clocked of almost 34 knots. The problem we had on the New Jersey was the fuel oil piping they spent more money on the weapons then the piping in the fire rooms. I have pictures of the engine room crew at the throttle board pointing at the rpm as we past zero. Captain Katz came down to all the firerooms and enginerooms and congratulated the crews.
sounds like somethomething a commander would do to prove the sahip being capable within his command, making the previous or future commanders either look average or poor most of the time. But this is coming from Army Infantry and my experience so take it with a grain of salt.
yes. we need them. because they put the fear of god into the enemy. it's not about the weaponry. it's about the armor. there isn't a conventional weapon on earth that can do any serious harm to them. imagine it from the point of view of the Chinese. they attack with a missile borage and score 16 direct hits. but do almost no damage. then we put a little lead in their general direction. score no hit but still do impressive damage. do not confuse it. these are the most powerful ships on earth.
As much as I want to say yes to reactivating, their time as active navy ships has passed. They are simply too old. I personally believe all 4 have found great homes and dedicated caretakers to help them enjoy their retirement, while at the same time are doing an excellent job showing the proud history of our navy and inspiring new generations of sailors..
@@TBreezy17Depends on who “they” are. If you mean the Navy, maybe, but they would never waste the time and money to do so. And if you mean the Museum, their contract with the Navy specifically prohibits such activities even if they had the will and the means. So, No, never again. 🤷🏻♂️
Well said. I think at this point we could not even supply a crew because the Navy is so short on manning. Also we are lucky that the ships are still here for all to see and visit.
@@andrewmunczenski3632Well put. These ships are simply too old, and too complex to crew in any manner short of a full military manner. So much that can go wrong and the last thing anyone would want to do along with losing such ship is trying to conduct emergency procedures this kind of ship short handed.
Those figures aren’t strictly accurate saying the plant was defective and thus had restrictions. I was a Steam engineer in the Royal Navy for 22 years, and when a Ship caries out a fully recorded Full Power Trial full power is the maximum shaft revolutions reached on that day and are recorded as the “New Full Power” until another trial is carried out. This figure is reached by several limitations that are reached during the trial, usually the main one is shaft torque when during the trial the torque meters are lowered to take readings and when a given maximum torque is reached no matter what shaft speed or knots the ship is doing at the time is now the newly recorded “Full Power” and that shaft speed is now the limit until another Full Power trial is carried out. The reason for this is that it is though not the only, but the easiest figure to register when the ship has to suddenly go to full power without having many other parameters checked over a period of time. So the Engineers just limit the Shaft RPM as they have Thea gauge right in front of them at all times. Some of the other factors would be Maximum fireing rate on a boiler, minimum steam range pressure, main engine condenser vacuum, turbine expansion measurements, Torque and a few others. Which ever was reached first them the Shaft Revolution would be recorded and that would now be “Full Power”. The ship would also have its own “Maximum Shaft Speed” which reached would also limit the trial. For instance a Leander Class Frigate had a “Maximum Shaft Speed “ of 232 RPM but during a Fully Recorded Full Power trial would rarely be achieved quite often due to weather conditions more than anything else or the steam range pressure at the time. The next time a Fully Recorded Full Power Trial is carried out the new maximum Shaft speed could be higher than the last trial, also the actual “Ships Speed” would vary especially just before docking and after docking due to hull build up. Hope this helps and it links to your Hull painting video the other day.😊
I was thinking something like that as the numbers go down on Higher loads. Doesn't seem to have something to do with turbine rpm just with the propellors having to work harder
Fully agree with this. To the layperson operating parameters can easily be confused as a restriction because they do not understand what is behind the numbers - and why should they. Certainly with the older propulsion sets a fully documented and ‘gauged up’ authorised full power trial was conducted over say, two hours, and there were many hours of analysis that followed both onboard and ashore to assess what actually happened during the full power trial both in terms of achievement but also assessment of the state of the main and auxiliary plant which could inform future physical examination during maintenance. I referred here to older steam turbine propulsion sets where instrumentation was shall we say ‘not the best’, whereas the more modern gas turbine propulsion sets had much better and reliable instrumentation which was much easier to assess when authorised full power had actually been achieved. Ex RN engineer here too.😉
The power plants were extremely reliable and relatively efficient. When someone walks through the engine room they see big boilers / burners, large box-like things (turbo and machine generators) and big reduction gear boxes. No one sees the absolute precision that each of these behemoth pieces have beneath the covers. Amazing machinery.
Well it is not like you can pop the hood and replace major stuff if it breaks down. Most of the larger plant equipment was there for the duration. So you really had to get it right the first time
Ryan, As stated in the documents you displayed, the restrictions were primarily based on the Torque Limits for the propeller shafts. A ship with a clean bottom starts out with limits based on the weakest part of the propulsion train. Here it was the #2 shaft. On CVN-65 Enterprise, the limits were based on the dental tooth coupling for the Low Pressure Turbine. As the bottom fouls, max RPM is lowered, to prevent overloading the critical element. These are all peacetime restrictions. In combat of emergencies, these details are the first ones to be deep sixed.
I also served on the Big-E. Was that always a limit or did the grounding in SF harbor in '83 add to it? BTW, I was in Main Control for that incident when I was the Auxiliaries Officer. We did replace #1 propeller peir-side afterwards.
@@PNurmi I had been out for a bit by then. Was on her from 74-77. To the best of my knowledge, that was the limit from the beginning. The story goes that the one time that limit was exceeded was on sea trials after the Core 3 overhaul. Rickover was in Central Control and called the bridge and requested control of the main engines. Permission was granted and Rickover ordered flank 172 RPM. He watched the readouts and then ordered "All EOS Central Control - Increase Main Engines 1 RPM" Which they did And he did it again, and again and again. The exact RPM that was reached has not been revealed, but as Rickover was reaching for the box one more time, the Westinghouse rep stepped up behind him and said "Admiral - One more RPM and you just bought those main engines and reduction gears!" Rickover hit the switch "All EOS Central Control - Reduce Main Engine RPM to 160" He then called the bridge, returned control to the bridge and walked out of Central without another word.
@@johntrottier1162 Yep, a classic Rickover story. Supposedly, he did something like that on a sub's sea trail that the CO countermanned not to be done due to the risks. SecNav Lehman then used that as a basis to remove Rickover. But that's the scuttlebutt on Rickover's "retirement".
@@johntrottier1162 That tracks with the Rickover stories I'd heard in Power School. Never had the opportunity to meet the man as he'd been dead for some ten years before I got to Orlando; and to this day if I'm not sure that was better or not. I served on a Nimitz class carrier. At least on my ship, at the time I was onboard (yep, I was a once and done nuke - and I knew ever at the time I'd regret it, but I had a young family to provide for and the stress was bad and getting worse), and due to specific configuration of installed equipment, the functional operational limit to shaft RPM wasn't due to any mechanical issue. Rather, it was due to getting energy from the pile to the turbines. IIRC, all the forward poppets would be fully lifted significantly before hitting the ship's maximum speed bell. From there, the throttlemen sat back and let the reactor operator work. Balancing the bridge's demand for speed with the EOOW and PPWO watching reactor power like a hawk was stressful, as the reactor operator kept shimming out to increase hotleg temperature - especially knowing that the reactivity increase was going to bite him in the butt a short time later! (and then again once the condensate pumps shot the additional cooled water back into steam generators) We had one guy who forgot jump-smile-jump once (hi Marc!), and he didn't just top 100% reactor power; he blew past it by a fairly significant margin! To the point that a short fast insertion happened (can't remember if the PPWO ordered it or it was an automatic function... happened 30 years ago and I was asleep in my bunk at the time). Everyone onboard was quietly freaking out; later, one of my topside buddies told me we were really bad at concealing our concern from the other departments - everybody knew the nukes were upset but had no idea why... and the rumors were awesome. (my favorite was that one of the reactors melted through the bottom of the ship and we weren't quite sure where we lost it) Anyway, about twelve hours after the incident, Naval Reactors sent a message saying we were bad little sailors but we didn't even come close to breaking anything so we should stop worrying about it. Didn't stop Marc from having to fully requalify as a watchstander, though. Made us all wonder what the real reactor limits would be once we were ordered to Battleshort, though....
I haven't finished this segment yet but I find it fascinating in light of the fact that the 3 Midway class CVs engineering plants were very closely related to plants in the Iowas and were operated well into the 1980s. The biggest difference between the 2 classes was that the Iowas had 8 boilers in four fire rooms whereas the Midways had 12 smaller boilers in 12 separate fire rooms. The engines and reduction gears as well as most of the auxiliary equipment were virtually identical. The Midway class plants were operated hard during the carrier's lives and provided a source of experience for reactivating the BBs. I served as ship's safety officer and OOD on CV-43 in the early 80s and was well familiar with her propulsion system.
This... Being the Coral Sea and the Midway operated as long as they did I think the Navy put the restrictions as they did out of an abundance of caution. Lets be real here for a moment. The FDR had probably more sailing miles on her than all 4 of the Iowas combined. Again probably an abundance of caution because if you break something replacing/repairing would have been difficult.
So a chance of getting food parts off some of the CV's if they did similar tests? If you needed a better set of turbine blades for instance? Obviously you can't get a complete turbine out of a bb little too much armor in the way. But parts that could be gotten below decks could be swapped then? I'd love too see them back. But unless it's cheap shore bombardment there is not much for them too do. But by God they'd frighten a few countries. A carrier battle group with one of these babies attached.
As Rear Admiral Danial V. Gallery wrote in one of his WWII books about the USS Guadalcanal, that the chief engineer kept a few RPMs hidden up their sleeve. He wrote that the chief said that the Guadalcanal couldn't do more than 200 RPMs, but when they were getting away from a U-boat sighting to let the destroyers do their work, he said that he saw the RPM indicator showing 214. Can only wonder if the same happened on an Iowa class ship between the chief and captain.
I love how much sailor art you have on your ship, Ryan. When I crewed civilian ships, the only art I usually got to see was a sticker here or there, and "WE WORK HARDER NOT SMARTER" written with a fingertip in the dust on a tank cover.
Every engine room has something painted on the air duct over the engine gears. Whoever had the best skills in artwork would get the opportunity. Some good ,some not great painting. My friend painted what you saw on this video
It's a remarkable achievement to reactivate and run a fourty year old ship , especially when it's not possible to remove and replace larger units by cutting a shipping route in the side due to the armour . Certainly it's a testament to the workers , museum staff and crews that the machinery spaces look in such good condition .
For all that people complain about how much armour you'd need to cut through to replace the engines, keep in mind that somebody had to rivet and weld that armour all in place to begin with when they were being built. It's not impossible, just a huge PITA.
Hi Ryan, You mentioned Iowa having a yard period where most of the funding allocated went to engineering upgrades without funding for gunnery repairs. As I read in the book " A Glimpse of Hell " the money to do the gun repairs was available but Captain Moosally chose to return the funds to the Navy and cut the Yard period short to impress Washington. Captain Seaquist, the former C/O of Iowa stated that Iowa was able on overload power to have made 35 knots ( documented .) Under Seaquist's command Iowa fired over 1,000 rounds of 16" shells without any incidents due to good crew training. Seaquist also was able to bring in an excellent Chief Engineer to get Iowa's powerplant in shape. He was later fired by Moosally. I suggest you read the book I referenced for a full accounting of Iowa's downfall under Moosally.
I tried to look up the speed figures in Norman Friedman's "US Battleships: An Illustrated Design History." Page 449 gives data for Iowa. Design figures are given as 32.5 kts at 212,000 shp. However, instead of a trial speed figure, there is a footnote that full power trials were never run prior to 1982. A BuShips estimate from October 1951 is that Missouri, with new larger-diameter propellers, would require 197,000 shp to make 32 kts, and 219,000 to make 33. It's a little unclear if the larger propellers were actually fitted, but they might be responsible for the small reduction in rpm compared with the others. There's also a statement that New Jersey's standardization trials in October 1943 yielded 220,982 shp, but no speed was taken (darn).
I spend a fair amount of time keeping equipment from the 30’s and 40’s running. Generally the more technologically complicated the device the more often I think it might just be easier, cheaper, and more practical to build a new one with modern techniques. I suspect a battleship would be the same. Just think of all the hidden seals, bushings, bearings, widgets, and bits that were never really intended on being serviced going bad, because they all will eventually.
Manufacturers in the 1930 usually built robust equipment and if properly designed last a very long time with good maintenance and proper operation. Today things are designed to fail, so the manufacturer can make profit on parts. Also the material quality is not as refined as it is today. There fore they built more bulkier and robust machines. The powerplant of a ship is its lifeblood. It has to be very robust if the ship is to be used for any amount of time. So today the powerplant is designed well, and you don't skimp on the construction of it.
@@wallyschmidt4063 Any part that is subject to wear has finite lifetime, wear will cause it eventually be out of tolerance. Engineering plants of many ships in WWII were worn out by the war. Many ships were scrapped because they were not worth the effort post war to refit with equipment.
What kind of equipment do you maintain? I'm part of the vintage/retro computer community myself. Most of what I play with is from the 80's/90's, but the oldest machine in my collection is a Burroughs class-9 adding machine in the olive green colour (which I think was built in the 1940's, maybe just after the war?). I can certainly appreciate the effort it takes to restore old machines, much less maintain them in active service.
@@wallyschmidt4063 They don't design things to fail, if you pinch too many pennies the maker has to compromise. Durability and maintenance etc is laid out in the requirements. Machinery now far more complex, more efficient, higher power. You can't 'Bulk' up a turbine to extend durability as wear changes the shape and atomic structure, and they require some pretty extreme materials. A piston operates at a far lower temperature. One needs kerosene, the other can use bunker fuel. One is near unreplaceable due to armour, the other designed to be replaced. Consumer electronic otoh, if you buy cheap, you get what you paid for.
I was an MM2 aboard the USS Coronado LPD11 (1973-75) in the aft engine room. We had several restricted RPM ranges that we were only to use in emergencies. As we answered bells we were instructed to pass thru these RPM ranges as quickly as possible. We were told these restricted ranges were due to excessive harmonics in the turbines/reduction gear. Main engines were 10K shaft HP driving 13.5 ft props (four blades I believe).
That's odd that LPD turbines had what's called a barred range because main steam Propulsion plants justify the expense to balance the entire assembly to eliminate vibration throughout the speed range.
Prior to watching the video, I felt that if the Navy were to seriously consider operating battleships again they would be better off building a new class. The Iowas are 1940s technology, so even if you could fix them up to perfect running condition you would still have to deal with the limits of their technology.
Fully agree. Probably also cheaper to build a new ship to modern standards than to rip out everything from an existing hull, especially a hull which has 40 years of military modifications and many following of civilian mods. But overall, these ships no longer really have a niche in which to operate as the guns no longer are the best weapon available for their mission. That money would be better spent on something with better bang/buck ratio.
Yeah, their time is gone and done. I worked as an engineer on commercial cargo ships. The oldest ship I worked on had my age, we shared our birth year: 1956, I was 22 at the time. Man, that ship had problems! We had two extra apprentices and a fulltime electrician on board to keep this thing going. Also the standard crew was about 5 man more as on modern ships at the time. I know, a warship is build to higher standards and there is no lack of crew, but the picture you painted of all the damage the ship took just by old age is very real to me! I stayed only two months on this ship because it was sold to a company in Hongkong. We were relieved by a crew of more then 40 Chinese. Imagine that nowadays.
These behemoths were this big only to support their main guns. Today we have much better weapons that do not require so much buoyancy, so their impressive size is more of a liability. They are gigantic targets for modern weapons. DESPITE THIS - I sincerely wish we could keep one in active service. They have a psychological value like nothing else we have ever put to sea.
I mean, it's kinda why we have two hundred thousand aircraft carriers. Not because they are efficient fighting platforms (they kinda are, kinda not), but rather because a carrier group showing up on your doorstep is a pretty good show of force. A smaller scale display of mutually assured destruction, if you will.
Most weapons are designed against unarmored targets so aside from modern torps a ship as massive and well armored as a BB is possibly more survivable now than when built where there were peers with 14/15/16" armed ships of their own. That said the Iowas are 80 years old give or take with a lot of irreplaceable parts since they haven't been made in decades. If an engine goes in any of them we'd have much less ability to repair than even in the 80's. The Iowa already had a turret blowout in her last deployment... and we're 30-40 years on from that... we'd be fools to trust 80 year old powder bags... and so on. Finally, there's the simple fact that the Iowas aren't ever going to face an opposing BB armed with 14"+ guns... and a big gun armed bombardment ship could be built to be much more efficient in that role since 10k ton missile armed ships like the Burkes, carriers and subs are infinitely more effective in anti shipping now.
A battleship is a bit like a 12gage shotgun: very effective for what it's intended for, but the reason cop like them has more to do with the psychological effectiveness before you shoot than what happens afterwards.
It amuses me DEEPLY when people say that ships and weapons are designed as though the enemy is un-armored. This is horrendously wrong. If you don't believe me, look at the warheads on Harpoon and Tomahawk. Also consider the larger anti-ship missiles the Russians built. You don't put warheads that weigh as much as a small car on a missile because armor doesn't matter. Unass your head :P
@@alphax4785 actually modern ships are not AS armored as an Iowa, sporting up to 6 or so inches. The 12" of an Iowa would increase survivability from a direct hit, but the ship's defense systems are too far out of dat to be viable. fun fact, breakthrough in hypersonic artillery technology by the U.S. could put guns back on the table to some degree.
For how much difference things make, I think the relevant measure is much faster the prop is moving than the water is. A little quick searching gets the data point that the inboard props have a pitch of 18.375ft and the outboard have 19.04ft. Combine those with the RPM's from the first table and you get that the inboard props would only produce any thrust at all up to around 35.8 knots and for the outboard 39.1 knots. The same math for BB-63 shaft 1 (outboard) gets 37.8 knots. If the ship is already doing 31.5 knots, that takes you from a difference of ~7.6 knots to only ~6.3 for drop of ~17%.
It would be interesting to see Wisconsin's RPM settings from the 1940s. Not all ships leave the yard straight from end to end. Most of the time it's corrected by setting the rudder slightly off zero and moving the pointer to show zero. Not all propellers are the same. I knew the last captain of the SS United States. He told us they had two sets of propellers for the ship. They were changed every few trips and set 'A' always gave a few more knots then the 'identical' set 'B'.
SS United States would visit Newport News for her annual overhaul, usually late in the year. Among other things her props would be swapped out for a new set. The initial set of props, the ones used during the Blue Ribbon run were relatively efficient but suffered from cavitation damage. I think they were made from a cast bronze/manganese alloy. A different set was used that was not quite as efficient but was more resistant to cavitation. Also, the ship was not quite as fast with the more cavitation resistant props. I can't recall what those props were made of.
Personally I think New Jersey and misourra might be the only ones fully capable of being reactivated but it would mean stripping Iowa and Wisconsin for spare parts and getting them across to the various navy fleet yards and stripping 2 of them to run the other 2. Basically they could reactive 2 of them but the spares required would have to come from the other 2. Since those 2 are most complete they should be the ones to do so.
I served 4 years in the Boiler/Engine room as a BT3 1970-74... the vast majority of new crew assigned to B-Div knew nothing about boilers or steam propulsion. They were chosen because they had a mechanical aptitude and we learned on the job. We did learn fast, I spent the first month tracing out every system by hand and had my own Schematic/Blueprint at the end.
First of all, fascinating presentation! What a find! Love the research. I would comment however, concerning the quality and the serviceability of the powerplant equipment. In a system as complex and as dynamic as these warships are, it's very common, at least in other industries that not all of the units will perform exactly as planned. I know that in the refining industry probably no process unit in operation today operates exactly as designed and most have restrictions of one kind or another. In other words, I wouldn't consider these issues to be a design error as long as the units are still able to perform the designed task. Your example of the USS Franklin Roosevelt highlights a cost/benefit analysis which was also probably influenced by the new nuclear super carriers that were in the pipeline at the time. But all in all, what a fascination presentation!! Update: Fascinating comments below from folks who've actually worked on these and similar machines! I've always wondered about the operation of the nuclear carriers which is some of the information contained in these comments.
It's very cool that they were watching for these problems and providing new safe operating limits. I see it like this. Grandpa can still help out with his abilities but you wouldn't ask him to run a marathon. :)
What puzzles me is that the Navy did have experience with the Iowas’ propulsion plants: Sacramento and Camden. And those plants were run alot more than the 4 Iowas were combined.
Good discussion. People post comments as if the Iowas were lightly used and could be reactivated at any time with minimal effort. The fact is, they were some of the oldest ships in the Navy even in the 1980s and were in rough shape in many ways. Even ships that are layed up in mothballs carefully deteriorate over time. On the major components, hours of usage is the bigger consideration, but steam systems consist of miles of piping and other components to which time is not kind. On Missouri, we were constantly chasing fuel and saltwater piping leaks. Part of our attention to damage control was driven by a concern about fuel leaks becoming main propulsion space fires. We practiced main space firefighting frequently, and were very attentive to our bilge foam sprinkler systems which were added in the 1980s along with Halon. Part of their high operating costs was the high level of repair maintenance they required.
My grandfather was a sailor onboard the USS Philadelphia (CL-41) in WW II.. At one point his ship was an escort ship for Augusta (CA-31) that transported President Truman to the Potsdam conference. My grandfather often talked about that trip as he said both ships ran 100% wide open to and back from the conference as they were worried about being attacked. He said BOTH ships ended up going directly into overhaul upon their return, and in fact the Philadelphia suffered permanent damage to her engines as a result and never was allowed at "full speed" again after that. He also said (and I wish I remember his name, but I don't) that he had a friend on the Missouri where the Japanese surrendered and that his friend told him that that convoy did the same as his did for the Potsdam conference, and basically ran "wide open" the entire trip to and back.. You might want to try and find records of Missouri after that event, I'll bet you may find the reason for the restrictions different than the others.
It is very interesting to glimpse the source documents. I think these ships should stay as museum ships. They have done their duty well and should be retired for good and used as inspiration for future generations. I think it would be much more effective to have a 'modern' ship(s) built with the requisite offensive and defensive capabilities, as necessary. Thanks for all the very interesting and informative videos you produce!! 👍
as much as they were a class of battleships, much of your videos prove each ship was unique and like the space shuttles, each had their own limits and restrictions as well as peculiarities
Similar was well known with steam locomotives of same design/blueprints/factory, yeah, they were the same on the blueprints but they had plenty of individuality in their behaviors.
I spent my working life in land based steam power stations, there is only so many times thing can be heat cycled before they need to be replaced, the stress on metal every time it is heated, expanded and then cooled again can only happen so many times before major failures, sorry for those that don’t want to hear this but these ships deserve a long quiet retirement
Generally the limit to rated turns was specified by NAVSEA based on how long since the ships last docking or hull cleaning. My first three subs were all old and >3 years since last docking...so they had hull fouling and NAVSEA didn't want the shaft overtorqued trying to reach 100% power. I've not heard of ships being limited by rated turns due to collisions or groundings...but I guess it's possible.
Well...since we are talking bent/busted ships here, I recall looking up at the CG USS Princeton drydocked in Dubai (I think) after the 91' Gulf war, they hit a mine that nearly broke off the fantail, it was being held on by welded on I-beams (like splints for a broken arm) along the sides, and steel cables tying it to the main hull. Not great for prop shaft alignment, ya know!😮 Its amazing that it was salvageable at all, and had to hitch a ride home on a giant ship transporter, much like the USS Stark and USS S.B.Roberts years before!.I later heard it was back in service with PAC fleet, but with speed restictions from high vibes. I'm continually amazed at how many USN ships with Major! damage make it home with living crews, due to solid construction practices and constant damage control training.
Love them! Toured the Missouri 2x in Subic 90? Saw the Whiskey along us in the Persian Gulf. Impressive Ladys for the day. Thankfully they are being preserved by people like you Ryan! Semper Fi Marines…. Love ya all but ya know!!
We were a Sumner Class destroyer. The engines were made by Westinghouse. At maximum speed, we turned the screws at 318 RPM which gave us 35 Kts. Those numbers were predicated on being light. Low fuel and low ammo loads. Remember, too, that getting to 35Kts takes 45 minutes. We rarely ran at maximum speed because of fuel consumption. The reality of transiting is 15Kts is all the speed you need to get anywhere. The NJ probably used the same strategy. Today, the main propulsion would be 8-GE LM2500' gas turbine engines. Roughly 200,000 HP.
Ryan you forgot to mention that the Navy did have a whole lot of experience operating with the Iowa engines as the Navy had been working with the identical engines for decades of the two Midway Class carriers, the Midway and the Coral Sea and also the two resupply ships which used the Kentucky engines.
As a former MMC/M-Div guy who spun a couple Navy turbines in my career, I would have to say that a limit on BB-63 #1 SRPM may not be due to the turbine, but the shafting, either between the main turbine and reduction gears or the propeller shafting. This could be a torque restriction on the shaft (did they find indications during NDT of the shaft during reactivation?) issues on the propeller Kingsbury thrust bearing ... without BUSHIPS/NAVSEA info, we may never know. As for the crew not having that propulsion plant training in the 80s, I went thru MM-A School in 1983 in Great Lakes. There were 2 steam "hot-plants" on base used to train young BTs and MMs. One was a 1200-psi plant for the newer warships, the other was a 600-psi, B-W dual-M boiler plant very similar to Iowa-class. I daresay they would have had availability to use those plants for training prior to sea trials.
Question - Given that some, i think all, of the Iowa class had various vibration issues at top speed, is it possible the idea of the restrictions was NOT due to wear or damage concerns, but vibration? IE, the CHENG played with RPM settings and these were the numbers that produced the least vibrations per ship?? As i recall in my readings in WW2 multiengine bombers, it was common to play with engine/prop throttle to get the smoothest flight as the craft flew and changed states from full fuel/bombs to bombs away/mid to low tanks. Once determined, those numbers wont change on these big gals - at least aside of replacing a prop or major component - so yer gonna wanna record those values. Second question - I think i asked before, but i will again - might the Museum be planning to digitize all these wonderful deep-in-the-weeds tech manuals? As a mechanic, power engineer and amateur historian, I would easily spend *days* going through them all. Perhaps collating them into a Kindle book or several? Possible fundraise avenue? Gearheads like me would happily pay to have even digital copies of these documents. Past all that, I definitely agree trying to bring back even one engine room, let alone four, would be prohibitively expensive. That said, I would hope to see at least one of the emergency diesels brought back. Never know when you might need to power your neighborhood ;) Side note - Holy crap. 19,000+ gallons of fuel per HOUR for full out. Suddenly nuclear looks a LOT more appealing!
I think there is still value in having the unique capabilites a battleship provides to the fleet, but the known deficiencies that Ryan covers in this video further support his assertion he has made in other videos that it would be better to build new than reactivate.
I’m not completely convinced that the time of the battleship has passed. We thought it had before, but then we ended up reactivating them again. Who’s to say that a situation that calls for a battleship won’t ever arise again? But then on the other hand, if we ever again reactivate the Iowas, I think they would be more difficult and expensive to maintain than ever before. If we ever need a battleship again, I think it would be better to just build a brand new one.
I agree, leave the Iowas in peace. They’ve done way more than they were intended to do. On the other hand, a modern battleship design could be very interesting. 🤔
The main issue is that there just isn't as much call for big guns these days. Just as fighter jets don't slug it out in dogfights any more except in the movies, the Navy prefers to settle conflicts at long range with ballistic and cruise missiles. Sure, the Iowa's can tank hits with their 12" armour (as long as it's not a torpedo below the belt), but their Mark 7 main guns only have an effective range of 23-29 miles. Nothing on the surface can live without the express permission of an Iowa within that radius, but ONLY within that radius. As long as you stay away from the Iowa, they're no more effective than a destroyer, assuming they're equipped with Tomahawks like in the 80's.
When you say “who’s to say that a situation that calls for a battleship won’t ever arise again.” Makes me think of a GI Joe episode from the 80’s where Cobra had some kind of EMP device to disable any kind of power plant. This device was on a Montana class battleship (they had them in GI Joe apparently) So GI Joe used the USS Constitution to get close enough to the Montana to board her and disable the device.
I would think that if we were to build a new battleship today, it would probably be similar in looks to the Zumwalt class destroyer, but it would be at least 50% larger, have armor of course, and big guns concealed by similar stealth plates that cover the Zumwalt’s failed rail guns. With modern technology, I would expect this new battleship to be much more efficient in every way than any battleship ever built before. Much, much longer gun range for instance. All the modern equipment would be tough enough to withstand the shockwaves from those big guns, or would have shield plates that would slide over and protect them while the guns are firing. This would be a completely modern battleship unlike anything that has ever existed.
That was some intreresting facts, you have a really fascinating job and able to pick "the real museum deal of the ship" like it it would be alive again
As it was explained to me in Shop 300,:(Design) @ LBNSY : At the time, you had nearly 50 y.o. turbines… Each had a different max. efficiency load, that’s why the suggested RPM’s on the props vary slightly. So a guide was created through sea trials, (shakedown cruises) by the chief engineers on each ship: by their reports, & sometimes our observations…to set average prop RPM’s for each ship, as the turbines, shaft, etc. are different. Also, as you know, the longer the propeller shaft, the more torque, stress, & strain is put on the turbine. This guide was merely what it states: a guide. All 4 Iowa-class ships have-had their own set of engineering problems unique to each ship. To replace the power plants was cost prohibitive, so these guides were created, so the ships would put be in drydock more than in the water. That said, BB 62 easily could’ve done 35 knots-plus at full speed, if needed. I was new in ‘86, & primarily worked on BB 63, but I remember the senior engineers in the propulsion-navigation section of my Design dept. in late summer of ‘87 (?) grumbling about BB 62’s new Captain “hot rodding” “their” ship.
The NAVY still needs a survivable platform that can do shore bombardment, just not the IOWAs. Basically, monitors like old Erebus and Terror. Marine diesel powered, auto-loading A/X turret ships with a focus on active protection systems to defeat incoming drones and missiles. Have them datalinked into the network so they don't have blast tearing up their own radar.
So... You want Burkes with new powerplants and a second gun on the stern? I'm not sure why a second gun would be better than a VLS array, but I can sure get behind updating the powerplant - I'd choose IEP or at least CODLAG instead of pure diesel, but hey, whatever floats your boat.
Burke's 5 inch lightweight gun can not perform the same mission as a volley of heavyweight shells from battleship/monitor class weapons. Thats why they reactivated NEW JERSEY in Vietnam, if 5 inch guns would do they had plenty already active in the fleet.
I was CENG on the USS Manley DD940 in the late 70’s this vessel suffered from lack of maintenance and improper/undocumented repairs while forward deployed in Greece. As well as POORLY planned and executed overhaul in Phila NS. The fuel piping had through wall leaks, fuel tanks leaked into fresh water storage tanks. Some high pressure steam equipment was not repaired and soot blower piping was replaced with thin wall tubing…..it took a great deal of luck and hard work by the crew. Unfortunately one squadron Officer became a casualty . The 70’s were a difficult time for sailors.
I wonder if they had brought back the Des Moines cruisers if they would've been more mechanically sound. Maybe not Newport News, but Des Moines and Salem had relatively low mileage and were in service later.
If we really see a need for better gunfire support/generalized naval gunfire (and there's a case to be made for it, particulary with the advent of cheap drone munitions), then the lightweight 8" gun/mount the navy spent forever designing has a lot to offer as a drop i replacement for the 5"er. That and a combination of 5" mounts being placed on LCS types (as they are cheap enough to risk inshore). The Iowas, though gorgeous, historical, etc, are a really expensive and manpower intensive way to fill a niche role. That said, naval gunnery in general is something that persistantly is useful beyond what wannabe futurists say. 3, 5 and maybe 8" guns have such a multitude of uses, especially when other capabilities are degraded, that we'd be fools to discount it.
Totally agree!! The MCLWG 8in gun is something we should be revisiting now!! A shame it was cancelled, as I recall the Spruances were built with the additional bracing to support the 8in gun forward, and the Ticos were considered for it, but don't think they actually were. The Burkes would def benefit from that upgrade!!
Interesting thought. I suspect with LCS - inadequate volume for a decent magazine. Aluminum - could they handle the recoil of a 5 inch. I personally want to see the new FFGs (constellation) get a 5 inch instead of the 57 mm. Come on - "recycle" the 5 inch guns from Decom CGs.
The time of the big gun ships has past. I dearly love all the big gun BB's and cruisers, at least we have all 4 Iowa's to appreciate as museums. I hope they are around for a long, long time.
The engineering side of the equation should not be a deciding factor, anything can be fixed just look at the aircraft recovered from the side of a mountain or the bottom of ocean, without the time pressure of war the repairs will likely be BETTER than new.
We built an 8-inch gun that was installed on the USS Hull, the Navy fired it a few times but finally decided the only shipboard gun they need is the 5-inch MK 45. BAE Systems.
Just to put it in perspective: These restrictions aren't greater than to still make them some of the fastest ships in the USN, faster than almost all NATO-allies ships and faster than almost all USSR, Russia and Chinese ships. For ships retained mostly for shore bombardments. These restrictions are for longevity and safety, not absolute.
I had a buddy served on Missouri in the 80s in Long Beach, paired with New Jersey. I remember him saying New Jersey was speed limited because her prop shafts were bent due to not being rotated occasionally in reserve storage.
Really enjoyed watching this video, it’s interesting to see that the navy acknowledges that the battleships are getting old and not many people new for this reason. If New Jersey was ever re-activated. In theory do you think they would refurbish or replace the engines. Because in the long run the ship would need to be efficient and cost effective? I know this would cost billions and would never happen? Definitely wouldn’t put a nuclear power plant in the ship. Might be bad idea?
I think the time of the battle ship is over. They are serving their country perfectly now. Our schools are not teaching history at they used to do. Having these ships are museums, allows people to see our Naval and countries history.
I don't think the navy brass ever wanted to reactivate battleships after Korea because of the operating expense compared to other ships. It took the Marine Corp demanding a BB for shore bombardment for the NJ to reactivate for Vietnam. Yet all 4 Iowas and several cruisers and destroyers were activated for Korea. After gas turbines became the prime propulsion for warships the huge engine room crews, fuel expenses, and the eventual crew retirement costs pushed the navy toward smaller ships. It took Reagan to get the BBs their last activation. The is no reason for BBs to be reactivated. Smart bombs and missiles do that job better and cheaper now and have a longer range. Any weapon that could be added to a BB could be added at less cost on a purpose built ship that would be cheaper to operate. Steam plants require heavy maintenance, frequent expensive overhauls, and much bigger crews the modern propulsion systems.
I think its time for a new class. The Iowa class are aging warriors whose new mission is to teach the citizens of her nation about their heritage. The psychological effect though, is unbeatable. So I propose a new class based on nuclear propulsion systems and newer weaponry.
Considering how many years the Navy had planned to keep them active (at least another decade), it seems the engines weren't a major concern. Even modern ships have major issues that come up with their engines and turbines. The turbine and reduction gearing technology hasn't changed much. Still very similar equipment. Cost vs benefit killed them.
I also suspect that due to a combination of factors, such as age of these ships, how worn out components are, also that there would be a big learning curve for sailors to learn how to operate these old battleships, I believe that these Iowa class battleships will remain as museums and never be reactivated again. Also these ships had steam boilers and steam turbines for propulsion. Today new ships are powered by either large diesel engines or gas turbine engines.
Gas turbines and diesel is a fair bit cheaper.... and for high power applications gas turbines is easier to manage - far faster upstart times compared with steam turbines.
As has been said by Ryan b4 it was impossible to bring the engineering plants completely up to par without gutting them thanks to the armor (internal belt) May be one of the many reasons the Montana Class went back to external armor... Had they.not been scrapped in mint condition the AK class may of been brought back instead simply due to low miles....
The days of the battleship are history. With technology giving us newer and more effective weapons, the need to have ships that can lob 500 pounds of explosives 20 miles is no longer the best possible weapon. The battleship was replaced as the Navy's queen of the fleet during WW2 by the aircraft carrier, further technology advancements such as missiles have further obsoleted the battleship. It was a marvel back in WW2, but sadly modern technology had made the battleship a relic of yesterday.
Today 1 missile or 1 torpedo can take down a ship. Alot is spent on defensive measures like CIWIS and anti air, anti ship , anti torpedo countermeasure. The farer away you destroy the threat (missile, torpedo etc), the safer your ship will be. The reality is that missiles are more accurate and are designed for penetration of target and then explode. While a 16 shell is just large scale destruction, so its not a nice precise clean weapon. But there are times when you need that big artillery. So today its a missile number game. Defence vs Offense. Fleet vs Fleet. To defeat 1 ship in a fleet, you would send 20-30 missiles at it to secure a hit against that ship (you need to defeat its defensive missiles and equipment) Modern missiles aren't designed to take out battleships (although a hyperspeed missile with enough kinetic kill could take out a good portion of a battleship). So you are looking at ships that can carry hundreds of missiles for defense and offense. And if you want those ships to survive, they need armor against missile hits. Catch 22. For putting missiles in the air the limitation is how many launchers you have. Vertical launch tubes solves this.
On the USS Bainbridge CGN25 the limit was on the torque twist on the long #1 ER propeller shaft. Max RPM / speed depended on the amount of barnacle buildup estimated on the hull and it's resistance.
Here in the Great Lakes owners are considering scrapping two 70+ year old ships, the Michipocotin and the Cuyahoga. As you may know the former suffered a stress crack in the hull while the latter has been through several fires. As much as I'd like them to stay in service, the fact is there are safety and economy issues involved. In the same vein I think museum ships ought to stay as they are. It's like replacing everything in a 14 year old beater to make it run two more years when you can get a new car. I'd like to go out in the Cod and see if it can run submerged in Lake Erie. Unfortunately there are insurmountable problems with that. At my trolley museum we have some cars we can restore to operating condition, but others we can only restore cosmetically as static displays. Preservationists just have to play the hand fate gave us.
A major factor in the reactivation of the Iowa class in the 1980's was President Ronald Reagan. He loved the image of the battleships and made a concerted effort to have them recommissioned. I believe that the Navy was opposed to this action. Ships do wear out, and warships probably wear out faster than civilian ships. I served on a LST that was commissioned in 1945, too late for WW II. It was reactivated for Korea and, when I was on board, served in Viet Nam. I was on board for a deployment to Viet Nam in 1968. In 1970 it was decommissioned and sold (given?) to Thailand. How long it served there I don't know. There is a LST of similar vintage beached on an island that is famously a Taiwan symbol of its resistance to China. No the Iowa's should not be reactivated.
I was Main Propulsion Assistant on USS Enterprise (CVN-65) and ten extra rpm at the top end would only buy a fraction of a knot. Also, acceleration and top speed were shaft torque limited.
As much as I'd love to have the Iowas reactivated, I know for certain that their time has passed. The era of the "gun battleship" is over, and ended with the introduction of Vertical Launch Cells housing missiles of all kinds. The era of the Missile Battleship was over before it started, it simply does not make sense to focus that much firepower in one spot when you could distribute the same amount of firepower among an entire battle group (VLS cells make it rather a simple task to do so). The only feasible improvement I can see to make to VLS cells is to make them less vulnerable to attack by changing them from a large number of cells with individual hatches, to a single or small number of hatches, made possible by mechanization similar to that used in a submarine's torpedo room or perhaps the magazine of a 5" QF naval gun as seen on cruisers and frigates. Basically, automated loading mechanisms to handle the missile containers and bring them into launch position. This would also allow for solving the other big problem with VLS cells. How do you reload them while underway? You can't really do it if the seas are rough, so doing it on the open ocean is pretty much infeasible. That's the limitation. Being able to take the missile containers below decks and use munitions handling equipment placed there for the purpose of replenishing the stores of the missile launcher thus created seems to me to be a better option, if only because there are 4 walls, a ceiling, and a floor to use to mount said munitions handling equipment.
The Iowa's can still tank hits much better than anything afloat today, the problem is their effective range. As long as you stay away from their main guns, they're no more effective than a destroyer with their Tomahawks.
@@BlackEpyon Exactly, and these days weapons are smart enough to bypass that thick side armor anyways, incoming "cruise missile" type anti-ship missiles will come in at roughly wave height + maybe 3.3 meters (10 feet) to avoid detection, and then enter a supersonic "pop-up" terminal attack mode to enable the warhead to strike the much weaker top armor of any given warship. Because of how ships work, you can't make the top armor very thick or you end up with a ship that's not seaworthy (it wants to capsize because it's too top-heavy). This whole missile attack paradigm renders the argument that "Iowas can still tank hits better" relatively pointless, because NOTHING manufactured within the past 50 years is targeting the side of a warship, save maybe submarine-launched torpedoes and even then anti-ship torpedoes these days are programmed to seek the middle of the underside of the ship as the point to detonate, seeking to break the back of the ship rather than blow a hole in the side. And the bottom of the Iowa class is also... not that thick, sure you can make it as thick as you want stability wise, but then you run into problems of making the thing float in the first place, so there too there is a limit. Point is, the Iowas have the vast majority of their armor in a place where no currently fielded weapon is aiming at. The situation ends up being similar to sending soldiers into the modern battlefield without kevlar vests, but with boots that can stop an RPG-7 round. Nobody's aiming for the feet, so those boots are just dead weight.
@@44R0Ndin You think that a Phalanx can't target a missile skimming the surface of the water? During trial runs, they had to turn down the sensitivity on those things because they kept shooting the splashes from the stuff they shot down!
@@BlackEpyon Right, but the Russian sea-skimming anti-ship cruise missiles typically show up not in 1's and 2's, but by the dozen. Not enough PD installations to cover that many targets, and not enough computer power on the Iowas to have each CWIS pick a different target. Not saying the problem is not solvable, just saying that the Iowas aren't really good for much these days.
@@44R0Ndin The Phalanx CIWS had it's own computer system. And unlike the Slava-class destroyer you're referring to, American CIWS actually work, because their search radars don't interfere with the comms. Plus there's also the chaff and flare launchers, even assuming that Iowa was travelling alone.
I think that they should remain as museum ships. I doubt that the Navy would reactivate them, primarily because defense contractor lobbyist and politicians would rather see shiny new warships. My only concern is that the Navy would decide to take them back and scrap them if there were a war so serious that there's a shortage of the necessary steel to build new warships.
We all want New Jersey in service. It's a dream, but a beautiful one. I don't think anything on this planet would make me happier than seeing New Jersey come into New York harbor under her own power. First under the Verrazzano and then past the Statue of Liberty. Yes, I know Iowa was part of Liberty Weekend in 1986, but Iowa isn't New Jersey.
Depends, if we are ever in a situation where were landing on beaches then maybe it would be worth it, it as far as it's too hard to cut holes in the hull to replace equipment, I say this, I don't think it's as hard as people make it out to be, we build aircraft carriers in sections that involves the moving of more steel then you'd need to cut trough, and we have better techniques for cutting and welding
Museum ships by day,, pirate Hunters by night! 👍❤ But seriously,, I wouldn't have minded if one or two were in Odessa right now, taking a leisurely Cruise around the Black Sea every once in awhile!
Ryan, giving examples for NJ was very good but not a huge difference. So clearly restricted but not 'limited' . BTW, at age 40 I had a number of restrictions on my body I didn't have when I was 20. The BB have had their day. The new wars are all airpower and air defence with a little of anti-pirate activity.
The modern Red Sea shows a pretty good case for naval superiority to protect shipping lanes, and a US/China war would almost certainly be heavily focused on that side. But the question is, do you go with missiles, or projectiles? I think missiles will take the cake on everything except cost.
With respect, we might be hitting the point where airpower - including drones - is overcome by defenses. Laser air defenses are starting to come online, and that makes interceptions remarkably inexpensive, and may possibly possible without any prior warning to the target. HELIOS, at least, uses an entirely optical locking mechanism. I'm sure laser detectors will start screaming, but by that point, the aircraft is already losing metal. A salvo of 16 inch shells doesn't care that it just lost a couple ounces of metal on one side - at worst, it's just going to tumble a little. Compare that to a Tomahawk - or worse: an F/A-18! I think its possible that there will be another paradigm shift in naval warfare in the coming decade or two. The current war in Ukraine was the first conflict with significant drone activity; and the situation in Yemen has underscored the asymmetrical cost aspect of offense to defense. It's very likely that R&D around the world is shoveling obscene amounts of money at any system that can reliably kill drones cheaply and reliably. The only programs that I can contemplate being close to ready is something that works like Iron Beam - and the US Navy has already started operational testing of similar systems. Will there be the return of battleships? Dunno, but so long as we keep fighting over the sealanes, there will always be the need for major combatants to project power in some form or another.
@@rearspeaker6364 so will a missile. My point was cost. You aren't going to want to spend a million dollar missile on a 1000 dollar hobby drone. The enemy is gonna flood you, and soon you are spending half your GDP on missiles, completely unsustainable.
Although speed of turbine could be a factor, its the mass flow of steam through the turbine and how fast the condensor can turn the steam into water, which could limit the turbine. The turbine will suck steam through it until its jammed by the condensor limitation and loss of vacuum. I think its more likely its the gearbox and heat generated by the gears and lube oil temperature which would be a shaft rpm limitation. Turbine- Temp and Pressure is converted into rotational speed. Concern clearance of blades. Gearbox- rotational speed is turned into torque. Concern is heat and adequate lubrication to the many bearings for the reduction gearbox.
16:35 It seems to me that all military equipment have the kind of issues you describe. It just the way machines are. Great video btw. I think the Iowa's have done their active duty and should rest as monuments to the people who served on them.
The little kid in me screams absolutely yes but in all reality I think these old beauties have done their countries proud. And deserve their time as museum ships now just like the Texas.
This can be boiled down to a kid wanting to drives dad's old sports car. But didn't have the money and experience to take care of. That's basically what this boils down. They just really wanted to use them but just didn't have the money or experience to know how to fix them up to be able to use them.
There was a time and a place for a battleship in the Navy. That time has passed. There are several problems with trying to reactivate them as they are now. The first one is that the fuel they use is no longer carried by the Navy. If we want to see what that would look like, I will direct you towards the Admiral Kuznetzov carrier operated by Russia. The second one is that there is no supply chain for spare parts. We have lost the capability to manufacture parts for these ships. The cost to have that capability restored would be prohibitively expensive. The third one is that the hulls themselves are old. Our oldest carriers are approaching the end of their designed life cycles. The third is that we have lost the skilled operators to operate the ship effectively. There are not very many people around that could still operate the ship.
As much as it would thrill me to see any of the Iowa class ships sail again, their time has passed. The age of the battleship is over and they better serve as museums today.
I think if there was a need for Iowa sized ships with big guns, it would be cheaper and easier and faster to build new ones instead of reactivating old ones and figuring out how the hell to get 80+ year old equipment to be well behaved again. Even if we literally had to rebuild the industry needed to do it from scratch.
@@rearspeaker6364 We can build the hulls and power plants for a ship that size, no question there. I'm more concerned about stuff like 15+" guns, the turrets, battleship-worthy armor plate, stuff like that.
@@Lessinath we can make the armor plate...the 15 inch gun barrels.....dont think the U.S. can do that anymore, but the army may, it's Watervliet Arsenal is still in use.
Ryan asked about reactivation. Reactivation would be a clear indication of national intent by the US. The time, the money, the people and their skills would be a clear message to anyone paying attention. The Department of Defense uses people, material, and money. The DOD does not produce a commercially viable product that brings in more money than it costs to produce. So, it is up to politicians and other “big thinkers” to determine and authorize, or not, reactivation of these ships.
I think it would be awesome to see one or two of the 4 Iowas to a goodwill tour status. As impractical as it would be, and also expensive, it would be so freakin cool to see an Iowa class steaming around the world again. I think with todays technology they could find ways to make the ships even more reliable and cheaper to operate. You could probably retrofit the boilers to operate electronically. Since the ship wouldn’t be in a combat situation. You wouldn’t need to staff all the gunnery positions, unless you wanted to do 16” gun salutes.
"But I will, 'cause that's what I'm paid to do." 😂 I thought you did all that you do for fun. Seriously this was anotherr very interesting deep dive video. Thanks.
A reduction gear being slightly out of spec causing overheating. Incredible. Each of these incredibly complicated machines have their own little quirks that makes them all unique. I couldn't imagine how that drove people in BuShips up the wall
Let's be honest. The Navy rushed to Iowas back into service in the 80s. I feel like all four were held together by hopes, dreams, bubble gum, and duct tape. Their time has passed as active combatants. It would cost more to *actually* bring the ships up to date (i.e. new engines and all the latest weapons and other systems) than to just lay down new ones, maybe on a modified aircraft carrier hull.
I would love to see some of these beautiful works of art put back into service. The intimidation factor alone would be worth it. If you put one of the BB's off the coast of Yemen I do believe their ships would not leave their ports. The United States does not really get into the kinds of conflicts that these ships were designed for so it would not make much sense to reactivate them but damn it would be nice to put one in the South China sea and dare anyone to mess with it!
What do you have to say about Capt. Seaquist of Iowa that said when he was captain in the 1980's Iowa made 36.5 to 37 Kt. and could keep that speed for an hour? Sounds like a major conflict with the story you tell. Capt. Seaquest said this in a interview with Drachinifel and is still on his channel.
The crews were operating equipment that was older, or much older, than the crew operating it. The crew members learned about and then operated newer ships before being assigned to re-activated old battleships.
Newport News Shipbuilding isn't a navy yard. It's a commercial yard. However they do mostly navy work. Mostly new construction aircraft carriers and submarines. They also do a lot of aircraft carrier upkeep and maintenance.