Florida-March 2011!Wow! Eerie 20 Minute, Loud Rumbling Sound *Video*

They’re about three miles south of the Tallahassee Regional Airport.
map

Here is a spectrograph of this bizarre sound:



747 Jet engine full throttle, same program, same track, so exact same plugin and everything:


A few things to keep in mind:
1) Very bottom is 35 hz
2) Notice what appears to be harmonic bands
3) Her camera likely could not pickup below 20 Hz, if that, and more likely 30 or 40 Hz on the low end
4) And that's what makes this even more bizarre. Had you been there, there was likely frequencies going way down to be shaking the house, and those are neither present in the wav file or in the spectrograph. The mic in the camera simply cannot respond to frequencies that low, so that must have been absolutely terrifying.
5) I'm stumped. Unless that was the most massive harmonic tremor ever, and Florida is getting ready to erupt with a supervolcano...

reply to post by TrueAmerican

Nice
Can you do/find any spectral analysis of plane engines that may compare...or not?

Peace,
spec
ETA: @ Beavis - Thanks Beavis, how'd you figure that?

I don't know what it is but I find the noise quite soothing on the ear.

I live in Iowa and I hear the same rumbling during the winter. It just goes on and on. I mentioned it to my husband one day and he said "its an airplane", But I pointed out to him that the rumble just continues and doesn't subside. Ive heard it go on for an hour, so I know its not an airplane. I also dont believe the thunder theory because we dont have thunderstorms in the dead of winter.

This intrigues me- Ive always wondered what causes the rumble!

reply to post by Beavis


Yep I see that.

I am going to do a service check of that airport for MRO or FBO etc to see if my theory is even possible.

Are there any weather reports available for that area.

It would be interesting to see if the wind was in the North.

In the spirit of ATS inquisitveness, I did a little digging on strange sounds and ran across this recent vid about sounds emanating from caves. The sound in the vid sounds a lot like the OP's vid, imo. So I tried to find if there were any cave systems around the area Beavis posted for the OP's story, and found in Marianna, FL, there is a cave system.
Going out on a limb here, but for the sake of speculation, check this out.
The sound starts at 2:35 and keeps going until it fades around 20 min later.

www.floridastateparks.org...

Peace,
spec

reply to post by speculativeoptimist


She calls the police at 6:37 and gives her location as spring hill road and walnut grove lane
I'm still leaning towards Independence Day.

Originally posted by JakiusFogg
To me, that sounded like a large aircraft doing Full Power Engines Runs.

They can last for some time. as they are timed for Exhaust Gas Margin calculation.

They can be loud, and if the winf is in the right direction then????

I am just saying that's the first thing I think of when I see that video. and hear the noise.

I'll have to agree! I live just a few miles from an airport and will say that I'm so used to that particular sound, it becomes background noise and hardly take notice to it. I watched the vid all the way through, and she does say that she's just a few miles away from the airport. Plus with that low cloud cover I'm pretty sure the sound was way louder than it would be on a bright sunny day!

My $.02

video.godlikeproductions.com...

Here is the MSM covering the story and I am not buying this!
Meteor burning in the atmosphere or something.. Whatever.



If the flash didn't happen at the end, I would have thought nothing of it but just something we don't know can happen in nature.

But there was a flash and the sound died...

I hear those noises just about every night between 2am and 4 am and the last for at least an hour and then just stop. We have an airport but it closes before midnight and opens at 6am.. My dad is retired from the railway and says its not trains. No military bases nearby....
BTW I live in interior of B,C, Canada.

OK Have found that there are indeed at least 2 MRO located at KTLH

One is called Aero Associates the other A.R.T.

The latter has capability to handle lager aircraft (up to 737). including engine change. After which a ground run would be necessary. with anything up to 65% N1, or higher if needed.

It's stab in the dark, but I am going to go with aircraft engine running. As much as I would like it to be Independence Day.

reply to post by iamcreation


That would be a perfect time for night maintenance.

What you could be hearing is the APU (Auxiliary Power Units) running, so the engineers can get line maintenance done.

Needed for towing and to get power on the aircraft, especially if they are busy and there aren't enough gennys

I used to live near an airport and they can be noisy things, even when "closed" for flights.

Originally posted by speculativeoptimist
reply to post by TrueAmerican

 

Nice

Can you do/find any spectral analysis of plane engines that may compare...or not?

Peace,
spec
ETA: @ Beavis - Thanks Beavis, how'd you figure that?

edit on 20-3-2011 by speculativeoptimist because: (no reason given)

Agreed, I think a side by side analysis of both would answer our question definitively! Great job TrueAmerican btw!

Jet engine?
Hmmmmm

Let's see, ground vibrating, 20 minute roar, flash of light, roar ceases seconds later. I am more comfortable not coming to a conclusion on this thing yet. BTW this was filmed on 3/9/11.

Ok, see above post, I edited it to show both, and I took care to get a very quality file of both at 44.1 kHz stereo.

They look a bit similar, but I dunno...tossup.

EDIT: hmm, the first one doesn't have the higher frequency content....strike one.

The first one doesn't have some of the lower frequency content....strike two....ummm...

Originally posted by TrueAmerican
Ok, see above post, I edited it to show both, and I took care to get a very quality file of both at 44.1 kHz stereo.

They look a bit similar, but I dunno...tossup.

EDIT: hmm, the first one doesn't have the higher frequency content....strike one.

The first one doesn't have some of the lower frequency content....strike two....ummm...

edit on Sun Mar 20th 2011 by TrueAmerican because: (no reason given)

That was fast, thanks!! They look different to me.

Originally posted by TrueAmerican
Ok, see above post, I edited it to show both, and I took care to get a very quality file of both at 44.1 kHz stereo.

They look a bit similar, but I dunno...tossup.

EDIT: hmm, the first one doesn't have the higher frequency content....strike one.

The first one doesn't have some of the lower frequency content....strike two....ummm...

edit on Sun Mar 20th 2011 by TrueAmerican because: (no reason given)

Thanks so much for that, super fast too- you must be non-government *haha*
I'm no expert in this subject but they look distinctly different to me...

reply to post by TrueAmerican


If you were to take in to account the fact that the video was shot right in front of the engine and the other at distance, with weather distortion. would this account for the slight sound degradation in the first.

I am no sound expert but what I see there looks pretty close to me

BTW, it was a 777 aircraft

RR Trent 800 engines.

That is a MASSIVE engine. bigger than anything you would see at KTLH. So that can account for the sound profile being bigger on the aircraft analysis.

From Flightstats I am showing lots of regional jets and MD88's

The latter there has a lesser noise category and uses the Pratt and Whitney smoke machines

I don't know.... That what I think it could be, it's it's not I ain't got a clue!!

reply to post by JakiusFogg




OK this is a typical plane at KTLH, bear in mind this is bearly 50% N1. no where near T/O power

This one at 2 mins is a good T/O power sound. Imagine this in a sustained engine run on the ground