"Jay Honeck" wrote in message news:9a5xc.

It may be the thrust reversing.

Nah -- it's the vortices whistling and zipping, after the plane has
passed.

It almost sounds like someone swinging a jump-rope through the air as fast
as they can whip it.

That's exactly what it sounds like. It's truly awesome on a good, still
night. It's so crisp that it seems like you could almost see it, like a
tornado.

In high school, I used to take dates out Marine Drive to listen to it. Heh.
No, really, that's why we went there.

-c