🚀 go-pugleaf

I did 4 days of backcountry hiking in Lassen a week ago and
had the bejeezus scared out of me twice by what I assume were
sonic booms.  Each time was in the early afternoon; without
any warning (such as a faint approaching roar of a jet engine),
a sound like a Howitzer exploded out of nowhere, followed by
the characteristic jet engine roar.  The first time, I saw 
a long exhaust (?) trail in the sky which rapidly dissipated.
Last year at Joshua Tree, I had a similar experience with an
F14 Tomcat or somesuchthing cruising along at less than 500
feet above the ground; no boom with this one, but I could 
almost feel the shockwave rolling over the contours of the 
landscape, and it was most unpleasant.

I realize that the flight paths of such annoying aircraft
would tend to be far from highly-populated areas; what I want
to know is if there's any way to find out supersonic flight
path corridors and avoid (or at least be forewarned of) them 
when I'm expecting some quiet and solitude.  Anybody have any
advice?

thanks in advance,

andy

[followups to rec.backcountry]