"Everett M. Greene" wrote in message
...
[The following is for idle speculation and mental recreation.]

A recent issue of Scientific American had an article about the
Earth's magnetic field reversals. The article presents some
plausible explanations of the reversals that have occurred
repeatedly throughout geologic times. It also presents some
indications that another reversal is like to happen soon (in
terms of geological time-scale "soon").

It was interesting to contemplate the consequences of a reversal
on our daily lives.

What is ATC going to use for headings?


Degrees TRUE.

You may be going geographically northward but the compass is
reading around 180. Which number do you use to describe
what's actually happening?


You throw away the compass and buy a cheap GPS.


Airways are prescribed on magnetic courses.
VOR orientations are aligned to magnetic directions.


But they don't have to be. The radials can be realigned to degrees TRUE.


I imagine that magnetic reversals don't occur overnight, so the
transition would be even more chaotic. We'd get a magnetic
deviation setting along with the local altimeter setting in
clearances?


Maybe a little chaotic for VFR types without a GPS for a short while until
they get one.

Magnetic navigation would cease to exist. All nav would be done by GPS.
All directions will be stated in degrees TRUE. Some repainting of runway
numbers required, to match.

Complete changeover in one month, tops.