

Spain builds submarine 70 tons too heavy by putting a decimal in the wrong place - stfu
http://o.canada.com/2013/06/06/spain-builds-submarine-70-tons-too-heavy/

======
damoncali
In the aerospace business there is a guy known as the Mass Properties Engineer
who gets to rule the project with an iron fist. He is responsible for knowing
the estimated, calculated or measured weight of every part on the spacecraft
from concept through to launch. It's not a very fun job, but it's very
important. Some people actually made careers out of it. You simply cannot get
this stuff wrong and not pay dearly for it later. There are reviews,
arguments, dealings, and handwringing over all of this.

Now, I have no idea if the Spanish sub business runs anything like that, but
it surprises me that it apparently doesn't or didn't in this case. It's not
like you just let some engineer in the corner calculate the weight and then go
build it. This is a systemic fuckup, not a shifted decimal point.

~~~
gmrple
My electrical engineering professors were constantly trying to ingrain in us
the tendency to estimate the solutions to problems long before solving them.
Why? because if you know the ball park solution you'll be able to catch gross
errors before they happen. Thus you will be less likely to pull a Homer
Simpson at the power plant or end up transmitting too much power from your
antenna. I'm thankful to be in an industry where catastrophic failure does not
have such harmful results.

~~~
anonymouz
Without more details it's hard to say what exactly went wrong, but it is not
at all clear that a ballpark estimate would be of any help here: The submarine
weighs 2200 tons, and they think it's 70 tons too heavy.

~~~
Someone
On the one hand, you are right. Preventing things like this (a 3% budget
overrun) in large projects is very, very difficult.

On the other hand, if this really is a single off by ten error, this was not a
death by a thousand cuts, but someone must have reported that his 80 ton part
only weighed 8 tons. That must have been noticeable, even if it got reported
for a 'part' where nobody has a natural feel for its weight (for example, what
do living quarters, with kitchen, supplies, and water for the showers weigh?)

------
patareco
Other explanation, more in line with the reality of Spanish reality.

[http://www.thelocal.es/20130520/530-million-bill-for-
spains-...](http://www.thelocal.es/20130520/530-million-bill-for-spains-
sinking-submarines#.UZvndKvSNk0)

> The president of the Navantia board has defended the work of the company's
> Cartagena shipyard and complained of "meddling" by unqualified people.

> He explained that it had been reported as far back as 2005 that the
> development process was not being properly followed and that there was a lot
> of necessary improvisation due to the addition of new elements at the
> request of the Ministry of Defence.

------
kryptiskt
> “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.

~~~
oneye
> 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)".

~~~
ingve
The studies supporting it have apparently been somewhat hard to confirm, a lot
of the source material used by McConnell seems to be from secondary sources
and self-referential. [1] is a detailed blog post where the author tries to
track down the original sources:

[1] [http://blog.securemacprogramming.com/2012/09/an-apology-
to-r...](http://blog.securemacprogramming.com/2012/09/an-apology-to-readers-
of-test-driven-ios-development&#x2F);

------
eridius
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 buoyancy calculations were wrong.

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

Sloppy reporting. Spain uses a decimal comma.

~~~
ars
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, presumably he spoke in Spanish, so translating decimal comma to decimal
point in English is not sloppy reporting - it's good translation.)

~~~
jsolson
> 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 convenient for most tasks. It
makes it difficult to escape local minima.

~~~
bigiain
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.

~~~
derekp7
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.

~~~
lostlogin
We get 355ml cans here in New Zealand - I had no idea it related to anything
at all. Thank you.

------
dm2
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.

~~~
Jare
$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.

~~~
dm2
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.

~~~
D-Coder
Or under water!

~~~
dm2
Not really practical for an aircraft to operate underwater, but someday
operating in space might not be inconceivable. My point was that for trillions
of dollars, the aircraft better do some cool shit. Yes, crash avoidance is
awesome, but not trillions awesome.

The sea is arguably more valuable than space in terms of military value, an
underwater vehicle is practically invisible and can deliver massive amounts of
firepower to any region in the world. Not to mention the secret mission
capabilities of submarines such as tapping undersea fiber and special forces
delivery.

------
maskedinvader
the article doesn't go on to explain more on how this could have happened, I
would assume they run some tests on the specs, or some kind of simulations (I
am obviously not an expert in making submarines) but considering they are so
expensive, wow, amazing. Someone put a decimal in the wrong place and nobody
noticed , what are the odds of that happening!

~~~
mpyne
It's not as unlikely as you'd think.

Even in the U.S. we used to routinely have to put in slop factors to account
for contractors that would routinely deliver gear in excess of spec. It wasn't
until the most recent SSN class that they were able to finally hold the line
against the contractors and sub-contractors... but at least the design itself
would have weighed what was expected.

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rmcastil
As I've come to believe its always a communication (or generally human)
problem rather than technical. Yet another blunder in line with the Mars
Climate Orbiter and the Gimli Glider.

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mikekij
Is there such a thing as submarine unit testing?

~~~
lmm
You can't exactly unit test the buoyancy - the hull is the only part that
floats on its own[1], all the other crap you put in would sink. The two need
to balance when you combine them, but there's no way to test that at the unit
level.

[1] Ok technically a few other parts like air tanks would float.

~~~
omegant
But you don't have to unit test a radio throwing it to the water. Just sending
messages.

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auctiontheory
Good thing they found the problem before the sub's first voyage underwater.

