Re: msnbc/oberg: 'Murphy's Law' rules outer space

From: Jeff Findley (jeff.findley_at_ugs.nojunk.com)
Date: 10/22/04 

Date: Fri, 22 Oct 2004 09:52:17 -0400

"Christopher M. Jones" <christopher.m.jones@gmail.com> wrote in message
news:opednYendPQal-TcRVn-hQ@comcast.com...
> To bring in a different set of examples, Mars Polar
> Lander and Mars Climate Orbiter. Different designs,
> different spacecraft, different sub-systems, both
> failures. The reason behind the failures lies not
> in redundancy but in the organization.

I made the point later in my posting that you shouldn't have your first and
only test flight also be the operational mission. That definately falls
into the "organization" category.

> > I'd actually say that integration testing and full up test flights are
more
> > important than budget and design.
>
> This also can fail. As with Galileo, where a g-test was
> performed on the Jupiter atmospheric probe. However, the
> test was invalid because the test harness was wired
> backwards (fyi, Oberg covers this in his article). An
> organization with a high rate of failure is also likely to
> have a high rate of failure in testing procedures. There
> is no silver bullet solution in design, or testing, or
> funding, or anything of that sort for organizational problems
> on this scale, the only solution is fixing the organization.

This is true. A healthy organization will generally perform analysis,
design, integration, and testing in far more optimal ways than an unhealthy
one. The challenge is how to change the "culture" so that the organiztion
becomes healthy. One way to do this is for everyone to really focus on the
processes involved and constantly work to optimize them.

Unfortunatley, I think that unhealthy cultures generally fight change. As
an example, they tend to implement changes like ISO standards to satisfy the
"letter of the law" instead of the spirit. Things like ISO standards can be
viewed as tools to actually help you improve you processes. Unfortunately,
too many companies become focused on ISO certification as a goal in and of
itself. In doing so, they completely miss the opportunity to add value to
their processes.

> Reusability doesn't necessarily gain you much depending on
> how you fly and test. If you fly irregularly and constantly
> tweak the vehicle then, as with the Shuttle, you never really
> know how reliable the mission is.

While this is true, I don't think of the shuttle as a truly reusable
spacecraft. You simply can't "gas and go" between missions. Remember the
times when the SSME's were routinely pulled from the orbiter and torn down
for inspections on each and every flight? That's not reusing the SSME's,
that's rebuilding them. Same thing goes for the SRB's. And the ET clearly
isn't reusable.

> If you fly regularly enough
> and start off with a serious testing regime then you can be
> more confident. However, for experiments like Genesis this
> really isn't the answer. A more bug-tested spacecraft bus
> (and return capsule) would help, but the spacecraft would still
> be fairly custom.

This is true. Until unmanned probes are being sent out in the thousands per
year, you're going to have real trouble getting the reliability up. We've
got a long way to go.

As for manned spaceflight, I'm betting the CEV will be about as reliable as
the shuttle. This is mostly due to similar (low) flight rates and the fact
that the same organization will be running the program. I don't believe
that there will be anything fundamentally different about the way the CEV
program will be run that will make it more reliable.

Jeff 

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