That's not quite it either, Joe. NASA was going to send up signals to
the MCO to burn certain engines for a certain number of seconds. To
calculate those times, they needed data from L-M in the form of computer
files. The contract specified that those files would be in metric units.
L-M supplied the data but in non-metric equivalent units. Since the
computer files contained only numbers, this was not apparent to NASA,
who took the numbers to be metric quantities. The engine firings were
conducted on those unconverted numbers and that put MCO off course.

A simplified analogy would be this. Assume NASA asked L-M how much to
change in velocity of the MCO was needed. L-M provides the number 10
[feet per second] and NASA interprets that as 10 [meters per second]
because the contract said that meters per second were the specified
units. Note that L-M merely says "10" and NASA hears "10", but both are
thinking in terms of different units. The result would be that the
orbiter would be given orders to change velocity by about 3.3 times as
much as it should have. L-M was culpable because the contract specified
the use of (certain) metric units for the provided data and they failed
to comply.

AAAS probably toned down the wording in that article and mentioned only
NASA by name to keep from stirring up another round of finger-pointing
and yelling.

Jim

"Joseph B. Reid" wrote:
> 
> James Frysinger in USMA 16919 quoted Science magazine of December 21 as saying:
> :
> >   In an epic snafu, the controllers of the Mars Climate
> >   Orbiter failed to convert English units of force into
> >   metric ones
> 
> My understanding of the snafu was exactly the reverse of Science's.  The
> NASA flight controllers ordered the Orbiter to make course corrections in
> newton seconds and the Orbiter, built by Lockheed Martin, interpreted the
> orders to be in pound-force seconds  Hence the Orbiter over-reacted.
> 
> Joseph B.Reid
> 17 Glebe Road West
> Toronto  M5P 1C8             TEL. 416-486-6071

-- 
Metric Methods(SM)           "Don't be late to metricate!"
James R. Frysinger, CAMS     http://www.metricmethods.com/
10 Captiva Row               e-mail: [EMAIL PROTECTED]
Charleston, SC 29407         phone/FAX:  843.225.6789

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