What's that sound the airplane makes?

SixPapaCharlie

SixPapaCharlie

May the force be with you
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I live under the 3000 ft shelf of DFW .

Periodically a plane will be landing and it will just sound like a jet. I'm talking about Jets here. 737s, 727s, 757s, 787s, 777s basically anything that starts or ends with a seven. Or I guess also begins with an A.

Where was I oh yeah.
Sometimes these planes are flying over and it just sounds like a jet and then all the sudden it makes this weird noise like
Whaaaaaaaarrrrrrrrrrhhhhhhh!

It sort of sounds like Chewbacca or a recording of a baby underwater played through a wah pedal.

It only lasts 3 or 4 seconds and it doesn't seem to coincide with landing gear coming down. It's not any sound that I recall hearing on the inside of the plane.

What makes that sound?
How do I make my plane make that sound?

If you don't quite get what sound I'm talking about I'll try to record it when one of these planes flies over. That seems way smarter than getting a baby in a wah wah pedal.
 
Maybe this:

It is known, it is the GTF (Geared turbo fan) jet engine, which makes at different trust levels strange noises, including at one trust level the the howling sound.

It is also called the "GTF Whale song".
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AvTalk episode 99 talks about it, see their description (emphasis mine)
On this episode of AvTalk, whale songs, a Vulcan howl, CHEWBACA'S GREETING—whatever you want to call it, Graham Webb from Pratt and Whitney joins us to explain the Geared Turbo Fan’s distinctive noise.
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Short answer, during large power changes, N1 and N2 can/will be spinning at different rpm’s. It can create a resonance as the engine sections equalize.
 
After landing, thrust reversal? I don't know the sound you're talking aout.
 
It just the engines spooling up from flight idle.
 
I hear something like that in Palm Coast FL, which I suspect is jets descending into MCO. It sounds like the power is getting reduced, but it has a very distinctive shift that only is audible for a couple seconds. The planes are >10k MSL when I hear this. I tried to look at arrival charts to see if there's a speed change, but can't tell from looking at them.
 
post #2 had it. It's a geared turbofan thing, most common offender the Pratts as seen on the A220 et al.
 
Two things immediately jumped to mind.

1st, I’m really disappointed we didn’t get a better description like this other famous Bri(y)an did (jump to the 45 second point):

2nd, I know it’s a different sound, but the blue note some jets make is similar:
 
Hang 4 said:
I hear something like that in Palm Coast FL, which I suspect is jets descending into MCO. It sounds like the power is getting reduced, but it has a very distinctive shift that only is audible for a couple seconds. The planes are >10k MSL when I hear this. I tried to look at arrival charts to see if there's a speed change, but can't tell from looking at them.
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I hear it too, every time I take the dogs out. I feel like it is most noticeable from the Airbus family, and also seems to correspond to ~10k feet
 
DaleB said:
My two favorites are 7 and 8.
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For 8, it was a fight between "Oregon Cherokee," "Vancan," or "JAFTHA" (Just Another F****** Tin Homebuilt Airplane). Getting too many RV-12s at my home airport to risk the latter two...They all have brawny muscles from working pop rivet guns.

Ron Wanttaja
 
jrcox19 said:
I hear it too, every time I take the dogs out. I feel like it is most noticeable from the Airbus family, and also seems to correspond to ~10k feet
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My home is located about the base-to-final turn zone for Sea-Tac airport, and we hear it occasionally. Certainly seems to be something with reconfiguring the aircraft for final approach. Once was told it was 757-related. Will have to fire up FlightAware next time I hear it.

Ron Wanttaja
 
wanttaja said:
For 8, it was a fight between "Oregon Cherokee," "Vancan," or "JAFTHA" (Just Another F****** Tin Homebuilt Airplane). Getting too many RV-12s at my home airport to risk the latter two...They all have brawny muscles from working pop rivet guns.
Click to expand...
I've heard "Ramp fleas" as well. I'm building with wood (just ordered a gallon of T-88 epoxy) and flying a -12, so I've got a foot in both worlds.
 
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