"Desert Shadow" <rch49ers@cox.net> wrote in message news:cc54b6aa-25dc-4fb7-b597-71c00f8bdd60@s31g2000yqs.googlegroups.com...

I ran out to the perimeter of Area 51 just to see what was going on.
Usually there is not much action on our side. Now the interesting
part, we both heard this strange noise. I have been to the GLR warning
signs at least 40-45 times and never heard anything like this before.
It sounded like a rumble just past the first set of hills. I thought
it sounded like a hot air balloon when they pull the cord to fill it.
It sounded like engine thrusting but there was nothing in the sky. It
would last 12-15 seconds at a burst and then stop suddenly. This
happened at least 3-4 times. Is it possible to hear engine thrust
testing from Groom at the GLR warning signs. To me it seems way too
far. I was able to capture this sound twice on my digital camera. The
video quality sucks! The loudest sound is my camera. If you
concentrate on the background sound you will hear the rumble. It was
quite noticible at the GLR. Everybody heard it and questioned what it
was. If you watch the two videos a few times you can hear the sound.
Any thoughts???

Video 1
http://www.youtube.com/watch?v=eeS5QmESmkw

Video 2
http://www.youtube.com/watch?v=8Udvostg6ew

Thrust noise can travel 20 miles or more. Especially at night. But that is over flat country here in Florida. Folks in Jupiter can hear Pratt & Whitney testing that is 20 miles out in the swamp.