I'm still amazed by this decision that dates from last year, and wondering why not re-use the full Saphir: if part of it is re-usable like this, why not use the full of it instead of cutting it and trying a challenging engineering repair of the damaged one.
I'm pretty sure it's because of the nuclear reactor which is in the rear half. The Perle's reactor has still some years to go, and it's much simpler and safer to simply weld the half containing the reactor, instead of trying to pry it open and move a live nuclear reactor from a boat to the other one.
Refueling a nuclear reactor on a submarine is very, very expensive. The Saphir obviously would need refueling to be put back in service, costing lots of money. If the Perle was recently refueled and the back part is where the reactor is, then it would almost certainly be cheaper to repair the Perle instead of refuel the reactor on the Saphir.
French submarines are a bit different from, say, US or British ones. They are refueled at 10 year intervals, and designed accordingly (e.g. there's a big hatch above the reactor which can be removed for the refueling), and they use LEU fuel produced in an enrichment facility that also produces civilian nuclear fuel.
This story reminded me of a project my father did with two 1965 Mercedes sedans; one was hit in the front, the other in the back. He cut them both in half where the roof meets the rear window, and welded and reassembled the two good halves into a perfectly functional car that we drove for years. Not the scale of the French submarine project, but the same kind of ingenuity -- it was still a big project to get everything rewired and all put back together, including bodywork and paint!
That sounds like the notorious "cut and shut" thing where criminals create a dangerous vehicle for the second-hand market, except that it's from a different era. Seeing as a 1965 Mercedes is built rather differently from a typical modern car, and safety standards have changed since then, too ... any comments on how hard it is to this without compromising safety?
I would guess that it is much more dangerous to modify a modern car because they utilize nontrivial shell geometry to improve the rigidity or to reduce weight. When I was attending driving lessons, my teacher claimed that the specific shape of the windscreen or rear window was a very important safety feature in the scenario that the car rolls over.
The big one is the A pillar on the front. This tends to corrode over time and is often why cars are written off. If it is corroded then the structural integrity of the car is compromised. There is really no repair for it - but a bit of welding can disguise things and get a write off sold as a potential project. The new owner can find out when they take the wings off... or they can find out when the front of the car comes off in the event of a shunt, but in that scenario they only find out very briefly.
That write-off is an economic affair, not a technical one. A-pillars too can be re-manufactured, but it is usually better not to because if the A-pillar is compromised you are looking at a body that will have a whole lot of other damage as well. The bad part about damage there is that you need to build it up from the inside out which means 'undressing' the whole box layer by layer so you can rebuild it properly, and most people will not have the time, the skills (or the jigs) to do this properly. But it definitely can be done, but likely not in a way that is economical.
I can't imagine an A-pillar that is damaged with the rest of the car being deformed as well, the A-pillar of a modern car is ridiculously strong and meant to be the outer boundary of the safety cage for the passengers. Any deformation there and you'll have a deformed bottom, roof, firewall and probably other parts as well.
My friend is a car mechanic and his weekend car is a 1985 Nissan Z31, which he welded from two halves - front and back.
It's physically possible to do it and maintain reasonable safety but you need proper equipment, skills and time.
The frame is generally not designed to be welded like that, so without reinforcement it will be significantly weaker.
He did is as a hobby project but generally done properly such operations are not cost-effective.
Nevertheless it's still a service some shops provide at the cost of safety.
My aunt used to have such a car - she only noticed because she was blowing through sets of tires - the halves were misaligned(rotated) by less than one degree in each axis, but it was enough to make proper tire alignment impossible.
Welding chassis of a car is a practice strongly recommended against, since it makes it significantly weaker at the welding point(s). It is very unsafe, although since it is an oldtimer restoration project, I salute your friend with respect!
The weld will be stronger, but the heat-affected metal will become weaker than the rest of the metal, which is why if it breaks, it will be next to the weld.
Only when done improperly. Yes, this is a common failure mode, no, it does not have to be that way.
Typically the reason is not that the heat affected metal will be come weaker, typically the reason is that the weld is thicker than the material right next to it creating a stress point in the structure. The hardening can be taken care of by annealing.
The best way to fix cars is to increase the length of the weld if you can, the original weld points are there for a balance between economy and strength. If you start welding in 'original new and interesting places' you need to plan how you want to achieve the required strength since economy is likely the least of your worries.
Every stretch limo is essentially a demonstration piece to show that this does not need to be a problem, and that you actually can re-inforce a body quite nicely. Keep in mind that the wheelbase of a stretch limo pretty much guarantees much higher forces on all of the welding in the body including the existing seams.
Depending on where you live, buying a car with this modification may require disclosure. There are plenty of videos on youtube about people buying cars which end up being two parts welded together. I don't think it is safe at all.
-Schengen(so a steady stream of cars imported from Germany with no additional fees).
-A Skilled workforce.
-Cost-conscious customers.
-Badly enforced regulations.
Which create an ideal environment for a cottage industry of shops which will take your storm-damaged aluminium roof sheets and turn them into an inspection, passing, moving car with a real VIN by next week.
I could create a Blade Runner'esque quote on stuff I've seen on the roads around here - especially regarding commercial vehicles.
It's less so like that than comparing to the 90s, but still.
> The frame is generally not designed to be welded like that, so without reinforcement it will be significantly weaker.
Welds can definitely be strong enough if done properly, as evidenced by the fact that welded parts involved in accidents can often be found to have broken somewhere other than a nearby weld.
However achieving the proper level of welding is easier said than done, and in particular being confident that a particular weld is done properly requires advanced equipment for non-destructive testing (x-ray, conductivity, echo ...)
You can hit it with a hammer and listen carefully! (No really, i've done some work on industrial robotics welding and it does this to produce a map of the weld it just performed for strength testing purposes - it can be done at the same time as peening)
Combining vehicles like this is one of those things that isn't bad but gets the Reddit experts screeching because their only experience is that their mom's sister's boyfriend's uncle's roommate got swindled by someone doing a crap job on a Civic that they thought they were getting a good deal on.
Vehicles build on frames are cut and extended/shortened all the time as a part of routine modifications for commercial use and it's far less labor intensive to "do right" than a unibody vehicle. Putting two good halfs together is no big deal and is a relatively standard operation, all the known techniques and whatnot transfers right over. (I assume a 60s Mercedes falls into this category.) Unibody vehicles are also routinely repaired in this manner in eastern Europe where it's cheaper to buy wrecked stuff from the west and fix than to buy new. In the west the limo and mobility van industry does very similar things (only they're inserting stuff in the middle rather than repairing the car)
People do cut and weld jobs all the time for their own personal vehicles and classic cars. When you're doing it for your own car or a car you don't intend to flip you can afford to spend the time to do it right.
There is/was lots of speculative armchairing as well, when HSLAs started coming into the picture. Structural adhesives also get pointed to as a reason not to do big repairs like this. In practice it isn't really borne out.
HSLA (high strength low alloy) steels are stronger (and therefore lighter) than mild steels. Many alloy steels (non-HSLA) are sensitive to heat treatment and improper welds make them weaker, so tons of people were being very vocal about HSLAs ruining cars, making repairs impossible, etc etc. Things like saying you'd need proprietary filler to match the composition, that welds would be poison, etc.
In reality it doesn't really make a difference.
Adhesives are also sometimes/often used to secure panels together instead of welds. The theory was that subtle differences in shape would introduce tensile stressed that would cause adhesives to pop in a crash. Not real. Alternatively stress during modifications could introduce cracks and weaken the adhesive- also bullshit, those adhesives go through stress every time they drive. They're fine.
They aren't invalid concerns, but unless you're putting a torch to the adhesive or welding seams down the middle of alloy beams, you aren't doing anything that will cause problems.
I think with the benefit of hindsight structural adhesives make things easier. Way easier to apply glue and clamp (or whatever the instructions are) than to weld somewhere you can't see without a mirror or building a custom spot welder tip that replicates what the robot used in the factory. I also like that you can not ruin the paint around an area where you apply adhesive whereas welding usually cooks off the adjacent paint. This is very beneficial in environments with corrosion. Holy crap are the consumables expensive compared to welding though.
> Things like saying you'd need proprietary filler to match the composition, that welds would be poison, etc. In reality it doesn't really make a difference.
The nice thing is that the car OEMs are high enough volume that even if they use something exotic someone will come along with special consumables or procedures or procedures or whatever that makes it trivial to work with. I hope some other OEM's follow Tesla with the stainless and we get cheap weld backing tape as a result.
I can't imagine it'd be all too tough with a 1965 car and good welding technique. At the time, cars were still pretty over-built and over-engineered. Good welds are pretty darned tough. Most things, you can cut-and-dice without problems.
With a 2020 car? I wouldn't trust it unless the person performing the work was a pretty good engineer. As engineering is more optimized, you can't just do stuff like this without being very careful:
1) Welds do leave a heat-affected zone around the weld which is weaker. If you're overengineered (1956) and everything is thicker than necessary, this doesn't matter. If you're near-optimal (2020), and using the exact amount of material needed to avoid failure under expected driving conditions, you might weaken things enough to see failures.
2) If reinforced, you'll affect the overall systems design. Engineered objects flex. Making one part more rigid than expected will put additional strain on other parts.
Counterintuitive as it might sound, optimal engineering makes designs safer. You analyze failure modes, put in appropriate safety margins, and do things right. Engineering classes drill that over-engineering is bad engineering. The flip side, though, is that if you can't tweak optimized designs like you can over-engineered ones without being careful and thoughtful about it.
Same thing with bikes. You can fix up a $100 Huffy with any old welder. A $2000 steel frame with thin-wall double-butted tubes? You want a really skilled welder and close inspection to make sure it's not compromised.
Please stop throwing generalized internet engineering tropes at the wall. Just because it all looks like rocket science to someone who doesn't have industry experience doesn't mean it is.
The repairs you are proclaiming to be impossible are perfectly possible to do with good results. These repairs are often performed often, just not in the high cost of labor parts of the world where HN lives (the low cost areas buy our wrecked cars to fix and sell to the point where sourcing parts for major repairs is often easier there than in the vehicle's country of origin). There's autobody industry specific tools and literature that help professionals in the industry perform the repairs properly. It's perfectly possible to take a car apart and reassemble (with good parts) the way an OEM would have if you're willing to invest in the tooling (mostly for welding in hard to reach areas). Car passenger cabins aren't supposed to flex (but in practice they do so within acceptable limits) and OEMs provide service literature telling you what you can and can't modify, much repair info can be gleaned by reading between the lines of such service literature. The welding issues you are describing are simply not an issue for skilled welders. Your opinion of engineering education is hard to reconcile with the observed performance of new engineers in any/every field.
The conclusion of what you're replying to: "You can fix up a $100 Huffy with any old welder. A $2000 steel frame with thin-wall double-butted tubes? You want a really skilled welder and close inspection to make sure it's not compromised."
Yes, it's possible, and yes, I know folks whom I'd trust to do it. The guy in my local auto shop? Definitely not. Random car shop in the developing world? I've seen the results. They'll drive, but they're far from save by Western standards.
What you wrote: "if you're willing to invest in the tooling" "The welding issues you are describing are simply not an issue for skilled welders"
I mean, seriously. You responded to a something entirely different from what I wrote, repeated roughly what I actually DID write, and mixed a few errors in (if car cabins weren't made to flex, they'd be using a very different type of steel; virtually everything made to be tough is made to flex).
Please find a place in my post where I "proclaiming [repairs] to be impossible"
> Anyone who has jacked up a car at one wheel and tried to open a door knows that flexing is very real.
Have you tried doing that to anything other than a 1960s convertible?
My 90s junk handles that just fine (and they're not particularly rigid cars). Matter of fact I did it yesterday afternoon to change rear pads.
Generally speaking you need to get a floppy vehicle really bound up (think 80s Jeep Cherokee or minivan off road) in order to have issues with doors and even then it's usually rear hatch only. OEMs specially try to avoid having bodies that flex enough to be noticeable to consumers, let alone to the point of doors not opening. Heck, I'd be surprised if you can even design a car to pass modern roof strength requirements without also making it stiff enough to have the doors open and close regardless of how bound up it is. (Pickup tailgates are another thing since the bed is open top and bolted to a frame designed to flex somewhat and even then being able to open the tailgate with two tires off the ground is not unheard of)
When I gave a friend a ride in my 2001 Miata, the very first thing he said was 'huh, you have a rigid frame, if I'd done that turn in my old MG, you could see the frame flexing'
Work is force times distance. How tough your car (or anything else) is depends on:
1) How much force it takes to flex it -- the spring constant
2) How far it will flex before it breaks
Multiply the two together (or specifically, 1/2 kd^2 where d is how far it will bend before it breaks, k is the spring constant, and 1/2 kd is the average force you're applying), and you get how much energy it takes to break it.
*Everything* flexes. Rigid things just flex less for the same force.
Things which break when flexed just a little bit are called brittle.
I disagree; I think the person you're replying to is completely correct. To rebuild the safety of a modern engineering system isn't somebody in their garage can easily do. With skills, you can definitely improve things, but not to the statistical level that modern car manufacturers have achieved.
It's similar in microelectronics. I can do a ton of stuff with an arduino because it uses really basic old, tough eletronics. I can put too much current into a pin, ok the pin dies but the AVR is still fine. A modern ESP32? A little bit of current or voltage above the rating and the whole thing is toast.
It's a numbers game, and you're overlooking the other side of it. The automakers have to engineer to a very low probability of failure because they deal in large numbers. It's true a person in their garage can't match that engineering - but they don't have to. They only have to get to "reasonably" safe not "absolutely" safe.
It's just like people putting turbochargers on their 90s Hondas. Naysayers could claim it's a fool's errand because if Honda, with all their engineering resources, didn't feel they could add turbocharging to their engines in the 90s and have it be cost effective and reliable enough, surely someone in their garage can't do it? But what they overlook is that if 5% of one of Honda's mass market cars blew an engine that would be a disaster, whereas a 5% chance an individual blows his own engine, which he may be able to replace for $500 to $1500: that may be a risk an individual is willing to take that a carmaker cannot.
You're overstating the difficulty/brittleness of "engineered" objects.
I used to be around the rally racing scene, and it's utterly routine there to weld tons of re-enforcements into the unibody. Most people with the money will straight up laminate the suspension mounts with plate. The safety cage makes the car incredibly rigid, as does replacing all bushings. The cars work just fine. The people doing this have relatively ordinary welding skills. Modern cars are not some sort of high tech magic that can't be modified or repaired with ordinary metalworking skills... it's just usually not cost effective to do so.
This is all true as long as the base material is steel. When you get into aluminum the number of people capable of producing good welds drops rapidly.
But you are on the money with the cost effectiveness bit, that's exactly why it is perfectly possible to do these modifications with confidence: you are not operating under a budget that gets counted out to the last 1/10th of a cent, so you can do it right, even if it costs a few bucks more. Something a car company operating at scale would never do. Once the cost constraint disappears there isn't a whole lot you can't do.
> any comments on how hard it is to this without compromising safety?
I would say it greatly depends on your welding skills. The same welded materials can be very solid of very weak depending on how they were welded. I would not dare to do that, personally.
Older vehicles are frame+body, such that the body integrity is less important than current unibody cars that don't have a frame. This would be a much more significant change on a unibody car.
Though any sort of big modification like this probably changes the characteristics of how it crushes in a crash, flexes under load, etc.
The devil is in the details. I know people that could pull this off. I could pull this off. But I also know people that would try to pull it off, it would look good and maybe even pass inspection but I'd never want to be seen in or near that vehicle.
I've welded up cars that were so rusted through that you had to re-inforce the body before you could start working on them in order for them to stay true (tubeframe inside the main body to fixate the remains). It's all doable, mostly a matter of time and skill.
While travelling in Cuba 2 friends and I hired a cab to drive us to Viñales from Havana - we ended up in a stretch Lada! Front ? of 1 car, back ? of another.
You've signed up with a throwaway account and started the last three comments I've read in this thread with a sneering "I'm pretty sure screeching HN/Reddit morons would think X but I know better"; it's against the HN guidelines to comment in that style: https://news.ycombinator.com/newsguidelines.html
"In Comments
Don't be snarky. [...] Please don't sneer, including at the rest of the community.
When disagreeing, please reply to the argument instead of calling names.
Eschew flamebait. Avoid unrelated controversies and generic tangents.
Please don't use Hacker News for political or ideological battle."
Ladas are(were) Eastern European Soviet block cars, with a reputation for being cheap and low quality, and in the UK, a low social status indicator used to mock people[1]. The joke could be that a Lada is already an unsafe car so a stretch-Lada can't be any worse (the joke is that you say one Lada is unsafe but actually they are ALL unsafe, ha ha). But then it doesn't need any mention of "99.999% of HN".
The joke could instead be that Ladas are safe enough, the stretch Lada was probably safe enough, and the thing to laugh at is the 99.999% of HN who can't judge the safety of cars, or naively aren't used to a world outside their Silicon Valley spafe-space luxury. i.e. it's a sneering putdown at HN users and nothing to do with Ladas per-se. Given the context of the last two comments I read by throwaway account starting with sneering at HN and Reddit users, and the need to specify "99.999% of HN users would say X", I lean towards this interpretation.
That doesn't mean you can't find it a hilarious witty comment, sneering at some "inferior" group is a popular thing people laugh at. (Weirdly?[1]) You might find it a funny joke, and it might be sneering and against the guidelines, both at the same time. "I loled" isn't sufficient to say it's on-topic, you should be arguing that it wasn't sneering. Better again, arguing that it was within the spirit of the guidelines more than the letter of them; just jokes alone are not against the guidelines explicitly but are frequently frowned on.
Sneerclub and status grabbing are my own personal soupnazi topics of the moment; once you see comments where the main purpose is to sneer at how dumb some large disparate group is, or the flip-side to claim status as a superior, you see them everywhere. e.g. these two just seen in tabs I have open:
My point was that even a normal Lada is going to feel like a tin can compared to what most people here have as their frame of reference. I'm not sure why anyone found that offensive. In retrospect I like the "stretch Lada is 5/3 as safe as normal Lada" line of reasoning better.
Thank you for your in depth reply!
Considering the author responded with His intention, it seems you have read the tea leaves wrong on intended meaning.
These are pretty common in Sweden because, if properly modified, they can be driven by a 15 year old as a tractor. While 18 years old and a more complete drivers license is required for a regular car.
And obviously because Volvo is swedish, that is the most common model to modify.
One of the required modifications is to remove the rear seat so that it is no longer built for personell transport. It should also not be possible to drive faster than 30km/h.
Interestingly ships get cut in half and reassembled "all the time". Certainly way more than people think.
See for example https://www.maritime-executive.com/article/photos-fincantier..., where an entire cruise ship was cut in half and an extra section was inserted into the middle before welding everything together again. I will also never forget the training ship of the Dutch Navy, which was shortened by cutting it into half and removing a section from the middle. Sadly this messed up the hydrodynamics fiercely and it was extremely seasickness inducing in even moderate seas. The ship certainly was effective as a training vessel though.
Cruise lines seem to have survived just fine and are starting operations back up (for vaccinated passengers). And if you believe that all publicity is good publicity they should have no problems filling those ships
This is turning out to be an interesting business model - there are obviously the "pay us and we keep your money, but keep offering you future cruises till the pandemic is over"
Additionally they are now offering "single country cruises" - start in one country, sail from port to
port in same country - which radically simplified the vaccination
It'd be nice if the US would ditch it's statutes from the late 19th century that make it illegal for foreign-flagged vessels from taking passengers from one US port to another.
This is why, for example, almost all Alaskan cruises sail from Vancouver.
Without those rules, what is to stop foreign vessels from replacing domestic passenger ships? The Staten Island ferry might just adopt a foreign flag and staff the ships according to foreign (ie cheap) labor laws.
It's a bit of a few different thigns. There are tons of ferries across the US and getting rid of that rule would require either rewriting the law to maintain the change for them or for every state along the coasts to do their own regulating. Then there's a desire to maintain some domestic shipping and ship building industry from a national security standpoint and from the goal of protecting the environment immediately around the US.
> Then there's a desire to maintain some domestic shipping and ship building industry from a national security standpoint and from the goal of protecting the environment immediately around the US.
This is the original purpose of the law, but it has failed completely and utterly. At some point you have to stand back and survey what the actual results of legislation are, as opposed to the intended results, and if those two aren't in any way congruent, scrap things and start over.
The domestic ship building industry imploded. America is an economic empire built on maritime shipping with only one remaining commercial shipyard capable of producing large vessels, and it is being kept alive with government contracts.
That has everything to do with lower cost of labour overseas.
Without the requirement for US ships to go from one US port to another, the shipbuilding industry would still be dead, and you'd have a dead shipping industry with it. You would have foreign-flagged crews moving cargo with foreign-built ships, against which you'd have zero recourse, in the event of disaster.
I would have assumed cruise-ship workers would come on land for long port stays. And that larger cargo vessels wouldn't stay long. How long can you stay in one place before it counts as residency?
The Egyptians have told him he cannot leave the ship. He has been stuck as its "master" for over a year. These things happen in the world of international shipping. Human rights tend to disappear.
The cruise line business is very cyclical so the companies hold really big piles of cash for when things get slow (like 2007-2008 financial crisis)
All the big companies had a couple billions each sitting around just for shit like this. They just fired most of the crew (they still need to have 100+ crew per ship to keep them in good condition) and anchored them waiting for better days.
With this reduction in costs they could easily wait out a year or two for business to come back.
The USS George Washington was originally going to be an attack submarine, but instead they decided to lengthen it by 130 feet & make it a ballistic missile sub. [1]
SSBN-626 and -635 were both ballistic missile submarines that were converted into training ships by going the other way and ripping out the missile compartment.
Those changes were made without any actual cutting though: the decision was made early enough in the process that there was nothing to cut apart. They just put some different pieces together than originally planned.
Source: personal conversation with Dr. Gary Weir, US Naval History and Heritage Command.
They spent 450,000 man hours to extend the ship from 195m to 210m long. That is a 7% increase in length. That seems like a lot of work for a tiny bit of gain.
They will spend a lot more man-hours than that, since the 450.000 hours only included welding the ship back together. The article also mentioned that the operation represents about a 12% increase in passenger capacity, since it's mostly cabins and amenities rather than non-money generating stuff like engines or anchors. According to wikipedia passenger capacity went from 540 to 608 passengers.
So let's do the math: The article states that "Pricing for the 7-day cruise starts at $5,600 per person." Presumably some passengers will pay more, let's assume an average of 6k/passenger/week. Assuming 45 sailings weeks per year (the rest being relocations and maintenance periods), the 68 extra passengers will bring in slightly over 18 million USD per year in extra revenue. Wages in Italy are not that high, so even assuming all workers are welders making the maximum from http://www.salaryexplorer.com/salary-survey.php?loc=105&loct..., it would only be about 20 EUR/hour. That makes the price of the 450k manhours "only" 9m EUR, so it seems likely they'll make back the total price of the expansion quite quickly.
Your analysis doesn't include the engineering to make this possible, the materials and labor to create the new section, the fees associated with using the dry dock, the lost revenue while the ship was out of service...
I find it hard to believe they will make it back quickly.
Yes, I made a few shortcuts. But is it really so hard to believe that the shipping company made a much more detailed analysis beforehand and decided it was worth it? It's not like you just YOLO a cruise ship into drydock and find out it's too expensive halfway through the project.
(Insert joke about software engineering budget bloat here)
What strikes me about your comment is that you think that a cruise ship company and their army of consultants and engineers would not have done the required calculations to figure out that they would make substantial profit on this over the long term.
I didn't say that. I thought it was interesting enough to mention. My assumption before reading the link was that it would have been a much more substantial change.
It makes me wonder if the fixed cost of the operation was relatively small, or if there was an outside constraint that meant further lengthening was not possible or profitable.
The fixed cost is 10's of millions, but the big thing to focus on is that 7% of the length of the ship is a much larger fraction of payload and that there are also two more restaurants included.
Yeah, it’s surprisingly common. For years when getting the a CalMac ferry from Oban in Scotland you could spot that the MV Isle of Mull had been extended because they had to repaint the ship’s name. That was done to fix stability as all the steel was right at the thickest end of the specified tolerance resulting in the ship being heavier than intended.
I think the "surprising" or unintuitive part for me is that I wouldn't have thought that a join could be sufficiently strong.
However, in another thread recently, it was mentioned that large ships can't support their own weight without water anyway, so I guess that the strength needed is mainly just in tension?
The front 1/3rd of the Maersk Honam was burnt beyond repair in a fire in 2018. That included the bridge and accommodation block. They cut it off, took the rest of it back to the shipyard on a heavy lift ship, and built a new front...
Depends on the project; for the cruise ship it's a newly built section built specifically for that ship and the submarines they were both the same design so as long as you cut in the same place on both ships they should fit together plus or minus 2x the tolerances it was originally built with.
Note that ships in the same class are rarely actually identical. There was also quite a bit of time since they were both built, and the later vessel no doubt incorporated changes / improvements on the design.
And then you get into the really fun stuff, where what's on the plans, and what actually got built are usually at least a little different... and maybe the as-built documentation was not finished correctly either.
They also sag. A half of a ship isn't as rigid as an entire ship. It changes shape in all sorts of unpredictable ways. There is lots of lifting and pulling before the two hulls line up well enough to start welding them together.
The overall structure should be basically the same though and any changes should be documented on a government contract like this so future maintenance and upgrades can be planned and built by any contractors.
That cruise ship example is wild. To do all that work (450,000 man hours) to just add 50 feet to the length of the ship... a 12% increase in passenger capacity. Obviously it must be cost effective but on face value it looks crazy.
My dad used to work for a ship servicing & repair shop ("Humber Ship Repairers"), now defunct. I remember them doing this to a Sally Line ferry. It was fascinating seeing the progress when we occasionally drove past the dry dock. Very little for a while as things were cut through internally, then suddenly one trip the thing was in two halves and the new middle was being put in place.
It does seem crazy. This bit in the article claims that a retrofit would be faster than building entirely new ships.
> The lengthening is a novel approach to adding vessel capacity as shipyard availability shrinks. With demand soaring, many cruise shipbuilders are booked into the early 2020s, and expedition/luxury lines are increasingly ordering newbuilds at yards that used to specialize in offshore vessels or yachts.
450k man hours = 225 people full time, 1 year @ ~ 70k a year = 15m
They added 34 more suites * 2 people * $1000 per person per cruise week = 78000 more per trip
~200 trips to pay back the cost - not sure what the utilization of cruise ships is usually, but if they do 40 packed cruises a year, they're at a ~5 year ROI.
I guess I forgot the cost of the new section itself, but I'm going to guess all in, < 10 years ROI?
The ship is a luxury cruise liner: the article, somewhere close to the bottom, says "Pricing for the 7-day cruise starts at $5,600 per person"
that 'starts" in the last part is kinda-important ... I took a look and they have 1 week cruises for $22,000
So, its really more like
34 more suites * 2 people * $5600 per person per cruise week = $380,000 more per trip at the low end
34 more suites * 2 people * $22000 per person per cruise week which is just over $1.4M more per trip at the high end
Assuming $15M from the 450k man-hours and $23M in materials for the retro-fit, (seriously over-estimating materials because I want the nice easy math that goes with a $38M total), it would be:
- 100 cruise-weeks or about 2 years to re-coup at the low end
- ~30 cruises (not cruise weeks, literally cruises ) to re-coup at the high end
Ford lengthened 50s-era freight ships used for hauling raw materials in the Ford River Rouge Complex an additional 120-feet in the 70s for increased capacity. [0]
Someone uploaded a TV special centered on the SS Byron D. Benson and its captain, in which he speaks to the lengthening and how it affected the ship. [1]
I like when the naming convention is consistent with the front half of the name going with the front half of the object, so the Zubian must have the front half of the Zulu...or the Sileighty must have the front of a Nissan Silvia (and the rear of a 180SX)
Reminds me of Finnish "Frankenhornet"; they attached the forward-section of Canadian F-18 to their own damaged F-18. Unfortunately the thing crashed during test flight after the modification.
This has happened before. After USS San Francisco collided with a seamount, her bow section was replaced with that of USS Honolulu, which was being decommissioned.[0]
These things make economic sense because nuclear refueling is a capital cost, and navies are loathe to waste a submarine reactor that has a decade or more worth of fuel left.
Super common to do stuff like this, when the USS San Francisco struck a sea mount (killing 1) she was repaired by replacing her bow with the bow of the soon-to-be-decommed USS Honolulu.
>In June 2006, it was announced that San Francisco's bow section would be replaced at the Puget Sound Naval Shipyard with the bow of USS Honolulu, which was soon to be retired. San Francisco is four years older than Honolulu, but she had been refueled and upgraded in 2000–2002. The cost of her bow replacement has been estimated at $79 million, as compared with the estimated $170 million to refuel and overhaul the nuclear reactor of Honolulu.
Btw, mer et marine is probably one of the best media if you are looking for french news relative to the maritime defense industry and the maritime industry in general.
Meanwhile, Britain has retired twenty nuclear submarines since 1980. None have been disposed of, and nine still contain radioactive fuel in their reactors.
No land-based ICBMs, and nuclear armed aircraft aren't a great deterrent these days, especially with the distance France's would have to go to reach a likely adversary.
You need a bunch because half of them will be docked (repairs, replenishment, R&R, etc.) at any particular time, and having just one at sea risks an adversary taking it out in a first strike.
The Saphir and Perle are attack submarines - they aren't France's nuclear missile subs (that's the Triomphant class, and they have 4 of them for exactly the reason you described).
France "needs" all this equipment because France (or least enough of its governments) have decided that it's important for France to have an independent capability to influence the world beyond "soft power".
It's easy to understand why they might want an independent SLBM force. And if you're going to be building nuclear submarines, may as well make nuclear attack subs so you can try to keep the knowledge and industry base more continuously active.
As icegreentea2 says, these are attack submarines, not part of the French strategic deterrent.
In a surface attack role a nuclear sub has a significant speed and endurance advantage. Conventional subs are can't adjust to course changes in targets very easily; of course, they are quieter and smaller, so choke point ambush becomes more feasible.
A nuclear boat also has the speed to keep up with a carrier battle group or a fast convoy. The ability to use SLCM to strike land (MdCN) or maritime targets (Exocet) without obvious forewarning is also useful.
Strategic boats are not used for conventional attack because it would reveal their location, and the launch of a ballistic missile could trigger real escalation towards nuclear exchange.
they are silent, and my guess is that it maintains expertise in designing military nuclear reactors which France need in their SNLA (submarines launching atomic bombs).
The best answer is an explanation in their own words, the French whitepaper on defense and national security: https://media.nti.org/pdfs/15-Fr.pdf . "Nuclear attack submarines carrying cruise missiles are a priority. Due to their stealth and virtually unlimited range, they represent versatile strategic systems that can be used for intelligence, protection of the nuclear submarines [here they are referring to their ballistic missile submarines], escort of the aircraft carrier or special operations. The White Paper sets a target of six submarines."
In addition, they can be used on their own to launch strikes against high value targets (things like the chemical weapons facilities in Syria). They are also very useful in the Indo-Pacific to deter China (France still has territorial possessions in southeast Asia): https://warontherocks.com/2021/04/how-franco-australian-coop... .
A great uncle of mine back in Eastern Germany (DDR back then) purchased a decommissioned pleasure boat, but it was longer than 25m so he would have needed a captain's license to operate it.
Instead, he cut out a part (most of the aft deck), and welded it together so that it was just below the 25m limit.
I joined him for a tour on it once, it was pretty awesome. The proportions looked a bit off, but it was much more spacious inside than typical hobby boats :-)
He and his family spent many vacations on that boat, touring much of the big European rivers.
> Luckily for the French navy, one of the Perle’s sister boats, the Saphir, which was retired from service in 2019, was awaiting dismantling at a shipyard in the northwestern port of Cherbourg.
Reminds of the stretched VW bus that a former hippy landlord of mine had. It was made from two buses, the front of one and the back of the other cut off, welded together. It was great for hauling kayaks in the back. I think the two constituent buses were from different years, so the model year of the welded bus was a 1966.5 or something.
"In June 2006, it was announced that San Francisco's bow section would be replaced at the Puget Sound Naval Shipyard with the bow of USS Honolulu, which was soon to be retired. San Francisco is four years older than Honolulu, but she had been refueled and upgraded in 2000–2002. The cost of her bow replacement has been estimated at $79 million, as compared with the estimated $170 million to refuel and overhaul the nuclear reactor of Honolulu."
https://en.m.wikipedia.org/wiki/System_D
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