I missed the staff meeting but the minutes show jim rozen
wrote back on 26 Jan 2005 14:21:16 -0800 in
rec.crafts.metalworking :
In article , Jim Stewart says...

Didn't work at Three Mile Island....

It would have if they had closed the relief valve
and took a look at their steam tables...

The pressurizer level indicator was hidden behind a huge
bunch of stuff, most of which they didn't need to look
at.

If I recall correctly, the control levers had been replaced with beer
tap levers. Seems that the issued levers were all alike, and you had to
look to be sure you had the correct one.

But your point is well taken - if they had done a
bunch of different stuff, the core would not have
slumped.

But they didn't. And it did.

Therefore the secondary cooling system did fail. It
failed because it was turned off, granted. Because
of the lack of appropriate human engineering it did not
work.

Ranging from using the same warning horn for everything. How can you
tell the difference between "oh my god it's gonna blow" from "somebody let
the coffee pot run dry" if you use the same klaxon for both?

Etc, etc.

It wasn't as if we didn't have experience with using all the human
senses to prevent accidents. The USAAF made the "wheels down" knob feel
like a wheel, while the "flaps down" knob feel like a little wing. Having
the gauges pointed the same direction when things were good, makes
isolating a problem a lot easier. Especially in multi engine aircraft.
Etc.


The same problem could crop up with a steam boiler
secondary cooling system.

Well, yeah.

But you can think it through and figure out where the problems are.

ALSO, and just as important, you can see what has gone before, to
discover what sort of failures had occurred and their causes. E.g. the top
sheet flashing problem.

tschus
pyotr



--
pyotr filipivich.
as an explaination for the decline in the US's tech edge, James
Niccol wrote "It used to be that the USA was pretty good at
producing stuff teenaged boys could lose a finger or two playing with."