Spanish sub - one way trip averted.

[3DDave]

https://o.canada.com/news/spain-builds-submarine-70-tons-too-heavy

"A new, Spanish-designed submarine has a weighty problem: The vessel is more than 70 tons too heavy, and officials fear if it goes out to sea, it will not be able to surface.

And a former Spanish official says the problem can be traced to a miscalculation — someone apparently put a decimal point in the wrong place."

"The Defence Ministry said technical problems are normal for projects of this scale." Ahahahahahaha!

At least no one was endangered. 70 tons is a cube of steel around 6 ft on a side. Out of 2200 tons it's not that much.

I ran into a similar foreign military sales bit where the foreign partner had responsibility for design, but my company was saddled with delivering a compliant item on a fixed price contract. It ended up nearly double the cost; no skin off the foreign design authority. Yeah, their engineers were totally shit which their in-house fabricators provided cover. Too bad our CEO was willing to help a bud out in a build-to-unfinished-print contract.

 

[JohnRBaker]

I know what you mean. Back when I was working in hard engineering (before I took a job in the software industry) one of our foreign divisions got a contract to design and build a machine that was installed at one of our large American customers. Unfortunately, it was a lemon and by the time it was put into production, we had closed that division as they just couldn't cut it. The problem was that we promised the customer that we would make it right and I got the job of coming up with a fix and seeing to it that it got implemented. The problem was that while the machine did run (it was a conveyorized cooler for a pie plant in Connecticut) it wasn't long for this world. However, the customer said the he needed to keep it in production and that we could rebuild it 'on the fly', which meant that we had an approximate 30 hour window once a week when the plant was shut down for scheduled and preventative maintenance. Now our office was in Michigan so I had to go and spend a week or so looking at how it was running, where the problems were and how could I go about rebuilding it without taking it out of production. I finally worked-up a proposal, went back home, did the design work and sold the idea to our management who in turn sold it to the customer. Anyway, every two weeks I flew to Connecticut, after parts had been delivered, and supervised our field crew to update a portion of the 800 foot long conveyor system during the shut-down window, restart the machine and make sure it went back into production before I could leave. I would then fly home and repeat the whole procedure in two weeks. Before it was over, I had made 23 trips from Michigan to Connecticut over a period of almost a year (the goal was to get the job done in 12 months or less, and we just made it). I can safely say that in terms of hours worked and miles traveled, that that was the busiest year of my nearly 49 year career working as an engineer.

John R. Baker, P.E. (ret)
EX-Product 'Evangelist'
Irvine, CA
Siemens PLM:
UG/NX Museum:

The secret of life is not finding someone to live with
It's finding someone you can't live without

 

[itsmoked]

Geez John, that sounds like hell. Guess you got some nice travel miles out of that.

What generally was it you had to 'fix' conveyor tracking problems? Refrigeration?


A heavy submarine. It's good it never made it into the water and it's good somebody did actually finally check the numbers.

It would seem fairly simple to add 6 meters to the hull though I bet that can cause some bending-moment issues. It should make the thing faster due to a longer hull. And, no doubt they could put and additional 204m³ (7,200cuft) (thousand square foot house) to great use.

I wonder if they've dumped the pesky lead acid batteries for Lithium batteries to shrink the space wastage by 10X and to ditch the 50% discharge limit torture.

Keith Cress
kcress -

http://www.flaminsystems.com

 

[JohnRBaker]

The pie cooler was not refrigerated, it just depended on convective cooling (as it moved along plus some fans) and time (hence the 800 foot length). The problem was how the cooler was driven. It was a single continuous metal mesh and there was something like 40 drive motors all driven from a single alternator that you could control the speed of, and hence the frequency of the AC current going to the drive motors to control the conveyor speed. The alternator was driven by a normal AC motor with an eddy-current clutch to control the speed of the alternator. Now the idea was fine and we kept that part of the set-up. The problem was that the 'engineer' who designed this had assumed that all of the drive motors would always run at the exact same speed, which was a very poor assumption. He had provided no scheme to compensate for differences in the speed of the drive motor/gear box arrangements. Since we didn't have the option of tearing-out the entire system and replacing it, my proposal was to replace the drive set-ups with a scheme that added a take-up section for each drive with a limit-switch so that when there was too much slack we would momentarily stop that drive until the slack was taken-up. It also turned out that the drive system was way over-designed and we decided that we could remove 10 of the drives which helped reduce the amount of work that needed to be done in terms of new parts and extra wiring. We got it to work by making one of the drives the master that never needed to be compensated, while all the rest were set to run just a bit faster to assure that there was always positive slack. While this created a sort of start-n-stop sensation, since the speed was slow enough and the structure sturdy enough that in the end it worked out pretty good. And since we basically rebuilt one drive unit per on-site work session, this worked-out well in terms of logistics and our need to spread this our over the course of a year.

As for earning air miles, unfortunately this was back in the 70's before airlines had frequent flyer programs. But don't worry, by the time I retired I had flown over 3.6 million miles on American Airlines AAdvantage Program alone (my wife and family used most of the miles, but we did get enough miles in the bank before I retired for a couple of first class vacation flights, one to Europe and one to Hawaii).

John R. Baker, P.E. (ret)
EX-Product 'Evangelist'
Irvine, CA
Siemens PLM:
UG/NX Museum:

The secret of life is not finding someone to live with
It's finding someone you can't live without

 

[IRstuff]

Yeah, dislike travelling enough to not accumulate the miles, but too cheap to buy them

TTFN (ta ta for now)
I can do absolutely anything. I'm an expert!

https://www.youtube.com/watch?v=BKorP55Aqvg

faq731-376 forum1529 Entire Forum list

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[SwinnyGG]

One mistake breeds another..

Spain's new submarine 'too big for its dock'

https://www.bbc.com/news/world-europe-44871788

 

[Sparweb]

That reminds me of this:
France pays $20 billion for trains that don't fit its stations

French state-controlled railway operator SNCF will be forced to modify more than a thousand stations after it was revealed that the 1,860 new trains it ordered at a cost of €15 billion ($20.5 billion) are too wide for many of the country's platforms. The mistake, which was revealed by satirical magazine Le Canard Enchainé, has already cost SNCF more than €50 million ($68.4m), as the operator started quietly "shaving" the edges of affected platforms.

No one believes the theory except the one who developed it. Everyone believes the experiment except the one who ran it.
STF

 

[3DDave]

Always good to see excellent control of requirements management.

I recall a product with a name like "True Number" (just Googled and didn't find it under that name) that was a requirements clearing house so that any document kept a link to a single source and would flag any document that had that number if the number changed, allowing whoever was in charge of the docs to manage the update. This was about 10 years ago.

 

[MintJulep]

@3DDave
That sounds very useful to me if you could stimulate your memory.

 

[Andries]

Transnet, the South African railway organisation, recently had the same debacle: new locomotives too wide for the platforms.

Andries

 

[thebard3]

Sounds like a common theme;

https://www.seattletimes.com/seattl...ay-be-too-big-to-fit-tracks-maintenance-barn/

Brad Waybright

It's all okay as long as it's okay.

 

[VEBill]

Nobody is learning?

BBC (2014): SNCF 2000 new trains too wide

 

[IRstuff]

Aren't those the same trains Sparweb cited?

TTFN (ta ta for now)
I can do absolutely anything. I'm an expert!

https://www.youtube.com/watch?v=BKorP55Aqvg

faq731-376 forum1529 Entire Forum list

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