Shame on the guy who did the original calcs and never documented the
assumptions. It is a pretty basic engineering skill to document what you do
along with the design parameters involved. If the original designer did this
then shame on those that followed and did not read it. Both software and
mathematics have one thing in common.. garbage in garbage out..
Dave
> -----Original Message-----
> From: owner-land-speed@Autox.Team.Net
> [mailto:owner-land-speed@Autox.Team.Net]On Behalf Of Joe & Lynne Lance
> Sent: Tuesday, November 23, 2004 11:49 PM
> To: Albaugh, Neil; land-speed@Autox.Team.Net
> Subject: Re: Traction Control and Bench Racing..
>
>
> Neil,
>
> Yes, the computer/software thing is worrisome for a number of reasons. One
> guy, Henry Petroski, who studies civil engineering failures, has
> identified
> a 30-year cycle when bridges and other structures start failing, even
> relatively new ones. Apparently what happens is that the guy who initially
> develops the design bases and formulas and uses limiting, but necessary,
> assumptions concerning the solutions of the equations, materials,
> conditions
> of use, etc. As time passes, other people continue applying the original
> design bases and formulas, but forget or ignore the original assumptions,
> exceed the validity of the original design bases, and things start to fall
> down.
>
> I saw this happen once when a guy made a perfectly logical
> assumption to do
> an analytical comparison of alternate space propulsion concepts. Trouble
> was, another guy came along afterwards and used the "comparison"
> results to
> design a "specific" propulsion system which failed because the logic that
> was okay for the comparison was actually illogical for the real world
> specific design. When that kind of mistake sneaks in it often doesn't get
> recognized until something bad happens.
>
> With so many people using "canned" software to design things and very few
> people using back-of-the envelope calculations, checking worst case
> assumptions, and a using a little imagination and insight with pencil and
> paper to check validity, I fear we could have lots of future failures.
>
> Lance
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