[Milsurplus] knots and The Gimli Glider

[Mark Richards]

Another part of the story is this...

The MEL (minimal equipment list) for the type of aircraft called for a stick
measurement of fuel if the onboard fuel metering equipment was inoperable.
In the case of this aircraft, the fuel indicator subsystem was labeled
"INOP" and there was a maintenance note about it.  In order to fly within
the constraints of the MEL, the ground maintenance crew had to perform a
manual fuel measurement.

This brought about the whole conversion thing, which would have been
unnecessary had the fuel data computer been working properly.

It was, incidentally, a simple conversion, but turned out to be something
the crew had not trained for, which leads back to both the government and
airline.  However, several crew and ground staff working on the problem
surely contributed to the mistake.  (Note the heavy reliance on instruments
in normal operations.  Take comfort.  They almost always work.)

As I recall the story, the pilot, named Pearson, now has an airport named in
his honour.

We have 10 fingers (most of us) and decimal units of measure are considered
intuitive.  I don't think there's much wrong with thinking of measurement
units in this manner.  I'd take a leap and suggest that the medical
profession, used to centimeters, millileters, micrograms, and all the rest,
would be making fatal mistakes all over the place if metrics were so awful.

Yours in millimeters,

K1MGY