
The Bug in the Physical Building - signa11
http://two-wrongs.com/the-bug-in-the-physical-building
======
femto
The original story in The New Yorker, by Morgenstern, has quite a bit more
detail

[http://people.duke.edu/~hpgavin/cee421/citicorp1.htm](http://people.duke.edu/~hpgavin/cee421/citicorp1.htm)

~~~
Animats
It's a much better article, too.

This has been on YC before:
[https://news.ycombinator.com/item?id=7605993](https://news.ycombinator.com/item?id=7605993)

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oddeyed
Supporting the analogy of this construction error as a bug, the error itself
was found by a person completely unrelated to the project who had access to
the 'source code' (built plans).

Source:
[http://www.onlineethics.org/cms/24528.aspx](http://www.onlineethics.org/cms/24528.aspx)
(via the Citigroup Center Wikipedia article)

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asmithmd1
Another example of a change made at time of construction that compromised the
design and wasn't caught is the Kansas City Hyatt walkway collapse:

[https://en.wikipedia.org/wiki/Hyatt_Regency_walkway_collapse](https://en.wikipedia.org/wiki/Hyatt_Regency_walkway_collapse)

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samscully
For anyone interested in this sort of thing "Why Buildings Fall Down" [1] is a
good related book. I did civil engineering at university and you'd be
surprised how many beautiful and interesting buildings only ended up that way
because of constraints forced on the engineers and architects by the
surrounding environment.

[1] [https://www.amazon.co.uk/Why-Buildings-Fall-Down-
Structures/...](https://www.amazon.co.uk/Why-Buildings-Fall-Down-
Structures/dp/039331152X)

~~~
thesehands
Likewise "To Forgive Design: Understanding Failure" [1].

[1][https://www.amazon.co.uk/Forgive-Design-Understanding-
Failur...](https://www.amazon.co.uk/Forgive-Design-Understanding-Failure-
ebook/dp/B00838XLJI/)

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michael-the1
There's also a great 99pi podcast episode about this.

[http://99percentinvisible.org/episode/structural-
integrity/](http://99percentinvisible.org/episode/structural-integrity/)

~~~
raisedbyninjas
This also goes into how the bug was found by a student who managed to contact
the lead architect and the process of quietly patching the building. The
repair happened under a deadline of an approaching tropical storm for added
suspense.

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gumby
I encountered concern about unorthodox approaches when building my house: the
code says that if you have a central support for the stairs and it is a
rectangular pipe of cross section X then it's OK. My staircases floated on a
set of plate struts -- basically climbable sculptures designed by the
architect. In order to get the permit approved we had to pay someone to write
a 15 page book full of differential equations to determine that indeed they
wouldn't collapse.

A pain, but worth it.

~~~
duaneb
Do you have any pictures? Sounds interesting, I'd love to see it.

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kpil
I think the author underestimates the inherent complexity in large scale
systems.

Yes, incidental complexity makes us skip tests that might have been good, but
it is the inherent complexity that explodes in our face when totaly apparently
unrelated issues causes emergent behaviour.

It has nothing to do with that it's a young field, it's just that we can
create complexity that is not bound by laws of physics.

I usually show 'business people' Conway's game of life, and they are always
fascinated, and then I ask them how many rules WE have.

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d33
Not sure if I understood it correctly - so there's a building that would
collapse sooner or later in a very dangerous way, but it's still there after
almost 40 years?

[https://en.wikipedia.org/wiki/Citigroup_Center#Engineering_c...](https://en.wikipedia.org/wiki/Citigroup_Center#Engineering_crisis_of_1978)

~~~
asmithmd1
When the bug was discovered (by an undergraduate architect major) they worked
nights and weekends to weld the bolted joints.

[http://www.slate.com/blogs/the_eye/2014/04/17/the_citicorp_t...](http://www.slate.com/blogs/the_eye/2014/04/17/the_citicorp_tower_design_flaw_that_could_have_wiped_out_the_skyscraper.html)

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bobbylox
If the author is here, there's a typo: "catastrophy" should be "catastrophe."

~~~
kqr
I genuinely did not know that was the correct spelling. Thanks! 10/10 bug
report.

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TrevorJ
The fact that they prolonged the fix in order to carry it out in secret seems
pretty damming. I wonder what the justification for that was?

~~~
digler999
The building wasn't in imminent danger of collapsing. One would assume that
had a gale-force storm been forecast for the city, someone would have ordered
an evacuation. However, had they tried to explain the situation, many people
would have over-reacted and refused to step foot inside, causing huge losses
for everyone.

~~~
EdHominem
Right, and it wasn't "in secret" \- they notified the authorities, etc. An
evacuation plan was developed and would have been used if the storm had gotten
closer to the city.

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eternalban
Not sure this can be called a "bug". This was a design error.

~~~
tantalor
Bugs are found in many different places in software (or hardware). Some
examples that come to mind,

    
    
      1. Design
      2. Implementation
      3. Configuration
      4. Deployment
    

I'm sure other people might think of some more.

~~~
HeyLaughingBoy
I've encountered Requirements bugs due to the requirement being flat out
wrong. Those are usually easy to find. Contradictory ones can hide until you
try to implement them.

But one of my favorite tricky ones was an apparently very clearly written
Requirement. It passed all the Requirements reviews, design passed design
review, code passed, etc. Then the original writer of the requirement went to
use the product and said "but that's not what I meant" Sure, I implemented
exactly what he _very clearly said (wrote)_ but that turned out to be very
different from what he _meant_ to say.

~~~
EdHominem
If all bugs were in code my job (as a programmer) would be so easy.

It's all the squishy human-worded requirements that cause the problems.

