Peter Dohm wrote:

The magnetic compass has exactly one thing in its favor, and that is just
plain old Brute Reliability.

I like the mag compass too. While they don't rely on any aircraft systems
to work, there are things that can cause them to be innacurate. The earths
magnetic field varies in strength and isn't all that constant in all
locations (and it's getting worse).

I was reading Lindbergh's book about his transatlantic flight and at one
point, both his whiskey compass and Earth Inductor Compass were just wobbling
around uselessly. Eventually, they both started working again on their own,
but he was guessing at his heading for nearly an hour.

I can relate. I have a video that I took on a cross country flight, of my
mag compass doing rapid 360s. It lasted about 5 min. and there were no
magnetic anomolies listed on the chart in that area. There were also no UFO
sightings reported that day :-))

John Galban=====N4BQ (PA28-180)

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