Very Loud Jet Engine Sound

Ok, first of all I'll note I live within a mile of alot of Boeing
owned property, and within 5 miles of the Everett Boeing plant.


I've noticed that over the last month or so at around 22:20-
22:30pmPST, there is this very loud sound that resembles a jet
turbine coming to speed, however it's loud enough that it actually
shakes the house a small amount, and is extremely loud when it
begins, but normalizes into a jet engine sound a few seconds
after, it lasts about 10 seconds, than quickly dies away.


Now I figure it's some sort of jet engine, since that's the closest
thing it sounds like to me, but everything about it seems odd to
me, the fact that if it is a jet engine, it's far enough away that it
should'nt be as loud, or shake the house, and that it lasts so little,
and that it's at night.


I'm wondering if anyone might be able to help me with this, what
kind of testing would be done that fot the above variables?

Engine testing, perhaps?

The fact that it is At night, Is brief, And intermittent would seem to suggest such ... most likely nothing more. Considering your close proximity to a known Boeing facility, it would only seem "normal" to hear these types of "sounds" at, what you may consider, odd times.

"At 9:27 p.m. PST we will be conducting a test of engine X111-A-b3. The test will consist of a 30 second power-up, followed by 15 seconds at full throttle, after which it will be shut down. This test is to gather data on the following parameters and charateristics of engine X111-A-3b ... blah blah blah"

Not an unlikely scenario ?

$.02

[edit on 10/28/2006 by 12m8keall2c]

That's what i figure it is, it just seems odd to me that they'd
do it at night, especially when the surrounding neighborhoods
are sort of sticklers when ti comes to disturbance of the peace.

I just figure it would make more sense to do it in the day time.

I agree with the engine theory. It's a good time to test and the fact that it only lasts for a couple of secods means that the engine isn't "on" for a long time wich again means it can't have flown.