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Spain builds submarine 70 tons too heavy by putting a decimal in the wrong place

o.canada.com

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Re: Spain builds submarine 70 tons too heavy by putting a decimal in the wrong place

#21

Post by dm2 »

Jare wrote: post #15
dm2 wrote: post #8

The other key figure is that the entire submarine weighs 2,200 tons. The sub was 3% too heavy and it will cost $14 million to fix, big woop, worse happens 1,000 times per day all around the world.

$14 million to find a solution, not to actually put that solution in place. A delay of two years in the $2.7B project will cost at least an order of magnitude more than $14M.

Even if it costs hundreds of millions of dollars, big woop.

How much have we spent on F-35 research, trillions? And those things don't even work in space.

Re: Spain builds submarine 70 tons too heavy by putting a decimal in the wrong place

#22

Post by dm2 »

muzz wrote: post #14
dm2 wrote: post #8

The other key figure is that the entire submarine weighs 2,200 tons. The sub was 3% too heavy and it will cost $14 million to fix, big woop, worse happens 1,000 times per day all around the world.

no, that's not the cost to fix the $14M is just for "an assessment of the problem with the S-80 submarine program and the scope of the work that would be required to correct it"

ok, so $14M + parts and labor

Re: Spain builds submarine 70 tons too heavy by putting a decimal in the wrong place

#23

Post by HNLogInShit »

eridius wrote: post #9

From the headline I thought that somehow they had attached 70 tons more weight onto the thing than they wanted (e.g. accidentally made the hull too thick or something). But from reading the article, it seems it's actually they just miscalculated the final weight based on the specs. Their miscalculation had it coming in 70 tons under its actual weight (which is 2200 tons). So the sub was built to spec, it's just the b…

This is what happens when you use commas instead of proper decimal points.

Re: Spain builds submarine 70 tons too heavy by putting a decimal in the wrong place

#24

Post by pbhjpbhj »

mdigi wrote: post #13
rtanaka wrote: post #10

Earlier quoted context omitted.

Just to add to that - it's $14 million on top of a $2.7 billion project.

This is a great example of an attention whoring headline. When you get into the details there's actually no news here.

Didn't they miscalculate a [the?] vital characteristic (buoyancy) on a 2.7B project. Seems news worthy.

Re: Spain builds submarine 70 tons too heavy by putting a decimal in the wrong place

#25

Post by bigiain »

jsolson wrote: post #17
ars wrote: post #11

Earlier quoted context omitted.

With the advent of computers and programming languages that only use decimal points, I wonder how long countries will hold out and continue using decimal commas. I would not be in the slightest surprised to see that engineering would standardize 100% on decimal points (even if the public used commas), just like how in the US engineering (except houses) uses metric, even though the public uses imperial. (Also, presuma…

> US engineering (except houses) uses metric, even though the public uses imperial. I don't know that I'd make this claim, in general. Everything from bikes to American cars can still be found with imperial nuts and bolts. Even the robotics work I did in school was mostly in imperial units due to the greater availability of, for example, 1/4" 6061 Aluminum stock. People will stick to whatever system is most convenien…

We've been "fully metric" here in Australia since the early '70's - I still find it amusing when seeing things like the building industries "standard sizing", where everything comes in 900mm increments and lumber all comes in sizes like "50 by 100mm nominal". Everything is still built out of 3, 6, and 12 foot two-by-fours and 3 by 6 foot 1/2 ply sheet - all labeled with metric dimensions of varying clarity.

Re: Spain builds submarine 70 tons too heavy by putting a decimal in the wrong place

#26

Post by akiselev »

fosap wrote: post #20
akiselev wrote: post #6

Earlier quoted context omitted.

This is an engineering calculation, it may not be guaranteed based on who they're working with and which standard they use.

I'm almost 100% sure engineers use the SI system. (unlike physicist that use a system that seems to be fitting). And the SI system says that 100.000 and 100,000 are the same. The Si system only uses space to group numbers like 12 343,123 12 for twelf thousand and so on.

My thought was that anything that used the decimal comma could be confusing when dealing with vectors.

However, I wouldn't go so far as to say they use SI across the board. I know aerospace engineering in the US can often switch between imperial and metric depending on which contractors work on the project (this resulted in a mission failure on at least one occassion: http://en.wikipedia.org/wiki/Mars_Climate_Orbiter) and it could be the same for other fields.

Re: Spain builds submarine 70 tons too heavy by putting a decimal in the wrong place

#27

Post by derekp7 »

bigiain wrote: post #25
jsolson wrote: post #17

Earlier quoted context omitted.

> US engineering (except houses) uses metric, even though the public uses imperial. I don't know that I'd make this claim, in general. Everything from bikes to American cars can still be found with imperial nuts and bolts. Even the robotics work I did in school was mostly in imperial units due to the greater availability of, for example, 1/4" 6061 Aluminum stock. People will stick to whatever system is most convenien…

We've been "fully metric" here in Australia since the early '70's - I still find it amusing when seeing things like the building industries "standard sizing", where everything comes in 900mm increments and lumber all comes in sizes like "50 by 100mm nominal". Everything is still built out of 3, 6, and 12 foot two-by-fours and 3 by 6 foot 1/2 ply sheet - all labeled with metric dimensions of varying clarity.

Same with the Mexican Coke bottles that we get in some US stores (Mexican Coke is made with real sugar). It is a 12 ounce bottle, labeled as 355 ml.

Re: Spain builds submarine 70 tons too heavy by putting a decimal in the wrong place

#29

Post by oneye »

kryptiskt wrote: post #3

> “Apparently somebody in the calculations made a mistake in the very beginning and nobody paid attention to review the calculations,” he said. Supporting the old software engineering folklore that the earlier a bug is introduced (and the later it is found) the harder and more expensive it is to fix.

> Supporting the old software engineering folklore that the earlier a bug is introduced (and the later it is found) the harder and more expensive it is to fix.

I wouldn't call it folklore as there are numerous studies supporting it.

EDIT: I decided to crack open Code Complete for anyone who is interested [1].

[1] "Researchers at Hewlett-Packard, IBM, Hughes Aircraft, TRW and other organizations have found that purging an error by the beginning of construction allows rework to be done 10 to 100 times less expensively than when it's done in the last part of the process, during system test or after release (Fagan 1976; Humphrey, Snyder, and Willis 1991; Willis et al. 1998; Grady 1999; Shull et al. 2002; Boehm and Turner 2004)".

Re: Spain builds submarine 70 tons too heavy by putting a decimal in the wrong place

#30

Post by D-Coder »

dm2 wrote: post #21
Jare wrote: post #15

Earlier quoted context omitted.

$14 million to find a solution, not to actually put that solution in place. A delay of two years in the $2.7B project will cost at least an order of magnitude more than $14M.

Even if it costs hundreds of millions of dollars, big woop. How much have we spent on F-35 research, trillions? And those things don't even work in space.

Or under water!
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