In message HxHud.9448$eb3.8331@clgrps13, Geoff Glave
writes
Any explanation for this?

FM radio generally operates at longer range than AM radio, however it's
limited to line-of-sight. However, when you're 40,000 feet up you can "see"
a lot of transmitters hence the FM signals.

Cheers,
Geoff Glave
Vancouver, Canada



The window holes are much too small to let the much longer wavelengths
of the 'AM' signals through. The body of the plane is a very effective
screen. The 'FM' signals can squeeze in, but it helps if you have a
window seat. I've also listened to SW in the middle of the Atlantic.

Flying from the UK to Florida, on the other side of the Atlantic the
first FM stations you hear are usually speaking French (from Quebec)
It's quite alarming!
Ian.
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