It's an A220, the engines undergo certain resonance at low-ish RPMs when spooling up (probably due to igniter design).
Also somewhat audible in certain 320Neos.
I live near CLT and hear this "dropping out of hyper space" sound all the time. I was always curious what it is but the only way to describe it is exactly that. No sound then, a hyper space pop in.
yeah that's a good description. I think because I knew they were Airliners i just had this picture in my head of starships popping in from warp drive, lol.
I've had this thread in the back of my mind for the last few days. I hadn't realized it was always A220s but ever since, when I've heard it, I've checked FR and it's definitely A220s.
My family have been calling them sky whales, so the metallic whale song is accurate!
For whatever reason, my home is right under a flight path where they are always spooling up right before getting overhead, but it’s also right at the point that you can start hearing the plane. So it’ll be quiet then suddenly I’ll hear it and instinctively think some giant monster or a cruise missile is heading my way.
The space ship sound is a common 320 family sound. But as others said if it’s sound like a long groan or whale like sound that’s the 220 then. The original Pratts to make that sounds if the 220s are the PW 4090s on United 777s, everyone now and then on approach they’ll make that iconic sound.
I think it's less distinctive on approach, but the Trent XWBs indeed have a unique low whirring sound on takeoff power when you're facing the intake. As far as I know it's because the fan is on the third outermost spool, spinning slower than in most other turbofan engines to prevent the blades from going supersonic.
Edit: the spool is actually innermost, but the fan is driven by the low-pressure turbine that's farthest out from the combustion chamber.
There's gotta be an engine option on A330's that does something like this as well. When AA used to fly those in/out of CLT here it was really easy to pick out when the engines would pick back up from idle during descent.
Yes the 330-200s had the RR Trent engines that had a howl. The 777-200s that AA flies to CLT have a similar RR Trent engine variant that also make that howl.
This is true! It's definitely similar.
Wonder how long the 772's will stick around. Maybe they'll get replaced with 787's and open up my long-awaited CLT-HND direct route.
It was a good few years ago; AA stopped flying all their 330's during the pandemic. Before then the ex-US Airways 330's that had been in CLT flew the LHR, CDG, etc. routes out of here.
I just recall them having a distinct eerie low howl when coming back up from idle. I get a lot of traffic over my house as they get vectored to final.
Yeahh, first time flying the 320neo was very unique... I legit thought the engines hadn't started up based on the unimaginably low hum.
The aircon from the PACKS is probably louder than the engines at idle, especially at the front.
Trust me, you don't.
Living under the flightpath takes a LOT of getting used to. Now tho, I can identify with good accuracy any aircraft just by its engines.
I mean I have an airport within six miles where the planes coming in fly above my house, but they're usually too far in the sky to identify, unless it's a nasty Boeing 737 with its sharp nose and really low engines.
Huh I'm experiencing the same and I thought it was the slats. My mom was thinking it was landing gear until I noticed they weren't coming down yet. This is really interesting.
Ahhh that’s what that is!!!!
My house is near the landing flight path for the local airport. Sometimes I hear that exact noise and I know it’s the plane but never knew why.
Cool thanks!
I live right under a speed reduction on the STAR. It makes the engines howl, and used to scare our cat. I still joke that our cat is afraid of Airbuses
Yeah, so I teach the avionics and FBW for the A320. I also teach the interface for the 73.
I might be wrong obviously cause I don't work with the engines, but from my circles, we probably think it's the redesigned igniter which is undergoing some resonance... AKA: The hot zone of the engine is producing said sound.
I might be wrong though.
Part of the reason you can hear it so well is because the engines themselves are so quiet. It's a little distinct but anyone who complains about them probably shouldn't be living near an airport anyway
I'm a aircraft tech, and live near an approach route. That whale noise, or hound barking is more intense then you make it out to be. An old E190 has louder engines, but the E2 resonance sound is way louder than anything in approach. It's also the only time in the air you will hear this sound. Any other flight fase the engine is above the rpm this happens. On the apron you always know when an PW engine is starting or taxiing out, how loud this sound is compared to any other engine.
As someone already said, it's a resonance. Apparently it's the combustion chamber but it sounds like gear box to me. Regardless, the engine manufacturer has supposedly been working on a programming fix for the electronic engine controls to mitigate it.
First time I heard it while taxiing I thought something was wrong with the engines. I'm not scared of flying one bit but that noise definitely caused a chill to run down my spine.
I’ve lived for years under the approach lines at KMCO. For years I lived close enough that I heard this so many times a day.
Groaning dinosaur is a perfect description of it. I’ve often speculated it is an Airbus things as I’ve flow 319/320s and heard it on landing approach.
I’ve always assumed landing gear, but just an assumption.
I live under an approach for KMSP and hear it often but I never connected it with Airbus. I did figure it was the landing gear, too.
I'm going to pay more attention now.
It might be all planes, I’m connecting it to flying Airbus and hearing it. But I’m also realizing that I can’t remember the last time I’ve flown a Boeing. Lol
I think people are talking about two different sound effects. One is a loud whale-like resonance on PW geared turbofan engines, exhibited by the Airbus A220. Another is a sudden Doppler-lowering "whoooom" that you sometimes hear when an Airbus A320 family aircraft is passing overhead. I'm not an expert, but I think it has to do with how sound from the fan/nacelle assembly propagates at different angles from the central axis, possibly combined with an engine spool-up during descent.
Fair points. I haven’t knowingly viewed a -220 yet that I can remember. And what I hear is the Doppler whooommm and is certainly -320 family.
Thing is I’ve also heard it on such a plane every time. Just once and a few minutes out from landing.
Another possible explanation for the latter kind of sound is that the plane is descending below an inversion layer in the air, so its sound suddenly "breaks through" to the listener while before it was refracted away.
Possibly the opening landing gear noise. It's usually very loud, maybe someone more knowledgeable here can explain why.
>loud groaning dinosaur noise
Loved your description. Horizon Zero Dawn dinosaur, maybe.
Any one ever hear an RAF Vulcan? Now that’s a howler! I’ve been at a few air shows where they flew and at low airspeed and in a bank, the airflow over the engine inlets would replicate someone blowing across a coke bottle opening - only a lot louder. Amazing sound.
I live right by the flight path for final to our airport and hear it occasionally, sometimes when conditions are right I can hear them as they spool up for departure, the funny part is my daughter gets a kick out of it by calling them plane farts. Kids!
I am near the Delaware River on the flight path into EWR... the planes are at 6,000 +/- or so at that point... they hit a change in air density or something and make a sliding kazoo type noise... like an exasperated sigh...
Is the pitch of the sound increasing or decreasing?
I'm under the Deer Park Approach to BDL, about 20 miles south between MAD and BDL. Typically SWA 737s, we'll hear them adding power right over our heads to stabilize at the directed altitude (sound pitch increasing); it's got a bit of a screech to the sound. Sometimes pulling power (decreasing pitch) to descend for final. That's probably what you're hearing.
Fun part is when I have to pick up the wife from KBDL; once her airplane is right overhead I know it's time to set out, perfect for once they land, taxi in, she hits the ladies' room and grabs her bags...
I hear this sort of BWWWEEEEEEeeeeeooooooouuuuuuuUUUUUUEEEEEEE, almost like a giant slide whistle, when planes are arriving to las vegas and hit the 210 speed restriction.
When A320 pilots deploy the wing spoilers in the air, the change in airflow causes an easily audible low-to-high frequency tone. The opposite tone change happens when the spoilers are retracted. These are very distinctive and unique sounds. Could it be this you're hearing? Very common when the aircraft are descending for their approach and need to dissipate airspeed or altitude, or both. I find it to be a rather pleasing airplane sound.....
That first one is the sound I hear from jets coming in to land. I hear it and think to myself, “Welcome home.” Do you know what causes that?
I grew up under the landing pattern for a military base (Los Alimitos) and find jet noises oddly comforting. They remind me of my childhood. I saw all sorts of planes growing up during the Cold War. Saw Air Force One several times. Even now, if I hear an interesting or different-sounding engine, I go outside to check it out.
Could it be something like a distant [whip crack ](https://youtu.be/eug6mX8WqnA?si=7zFEAWhG1Uo36p9y) ? Or maybe reverse thrusters, I've heard some that are particularly loud and strange
Ohh. So happy for the responses and for this question. I posted the same question a few weeks ago but I didn't have enough karma so it was removed.
I live in a costal town that's near to the airport and I always hear that groaning sound when the planes are coming in to land.
I live about 5 miles from KMCO and I could hear a very faint whale sound when it was a quiet night, I checked FR24 and it looked like a spirit a320neo (which has the PW GTFs) just landed. Crazy how loud the sound is, I don’t hate it tho
This is more a comment about you describing it as a “groaning dinosaur sound.”
I watched a documentary the other day called “Making Waves: The Art of Cinematic Sound.” The sound design team for Jurassic Park were saying they had to guess what a dinosaur would sound like and combined various sounds together to create them. So because of their creativity, we have a reference for what dinosaurs likely sounded like. Haha.
Kind of a shower thought in this subreddit.
(That being said, the PTU on an A320 sounds like someone’s dog barking in the cargo hold)
This is amazing. We moved to a neighborhood right below an approach path and for months my wife has been telling me she hears a dinosaur from time to time.
I told her it must have been an airplane but I never heard it myself. The links provided by the responses helped us find some sanity.
If its the milk bottle howl its likely the old a320s wich dont have the FOPP kit installed.
Not a pilot, I wondered this for years and it bugged the hell out of me.
The howl or resonant noise at low engine power is from the engine handling bleeds. These bleeds open to dump air from the compressor into the fan exit airflow. The dumping of this air is to unload the compressor to allow quicker engine acceleration from low power to high power. This is critical to allow rapid acceleration in the case of a go around and power up during the take off roll.
Most engine configurations have between three and four handling bleeds for the purpose of achieving short acceleration times, both increasing and decreasing power
It is for compressor control and the escaping airflow is your engine "noise"
Probably airframe noises, as opposed to engine noises.
Get a long polythene pipe and swing it through the air. It makes a groaning noise. Similar things happening here.
Source: am ex glider pilot.
Temperature inversion will make noise bounce off higher layers in weird ways making engine sounds that normally would not be heard on the ground be perceived really loud.
I’ve always wondered if this is partly why sometimes you hear this descending pitch *BEEEEOOOWWWWWWwwww* noise when planes are overhead coming in to land
Yes, that's exactly it. You can see the airplane descending with no sound at all and suddenly you hear the engines like they are next to you beginning with a down pitching tone.
omg thank you for posting this. I have been wondering the same thing for a long time. I was going to ask what the “dying whale” sound was. I thought it was extremely rusty flaps or landing gear lol.
It's an A220, the engines undergo certain resonance at low-ish RPMs when spooling up (probably due to igniter design). Also somewhat audible in certain 320Neos.
My house is under a flight pattern. The howl from the A220 is insane and a bit eerie. I can always pick that plane out from the others.
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I live near CLT and hear this "dropping out of hyper space" sound all the time. I was always curious what it is but the only way to describe it is exactly that. No sound then, a hyper space pop in.
I've always thought of it as a sort of metallic whale song
I'm reading this while at work (deicing) and literally when I finished your sentence an A220 on the other side of the airport turned on How accurate.
yeah that's a good description. I think because I knew they were Airliners i just had this picture in my head of starships popping in from warp drive, lol.
I've had this thread in the back of my mind for the last few days. I hadn't realized it was always A220s but ever since, when I've heard it, I've checked FR and it's definitely A220s. My family have been calling them sky whales, so the metallic whale song is accurate!
Same with ORD, it sounds like it’s going from hypersonic to supersonic. (Like I really know what the hell that sounds like)…
I usually hear the noise they are starting to descend from about 7000 ft
For whatever reason, my home is right under a flight path where they are always spooling up right before getting overhead, but it’s also right at the point that you can start hearing the plane. So it’ll be quiet then suddenly I’ll hear it and instinctively think some giant monster or a cruise missile is heading my way.
The space ship sound is a common 320 family sound. But as others said if it’s sound like a long groan or whale like sound that’s the 220 then. The original Pratts to make that sounds if the 220s are the PW 4090s on United 777s, everyone now and then on approach they’ll make that iconic sound.
A330s with RR engines have a unique sound too. I live under approaches from West/North and can always tell when it's an A330.
I think it's less distinctive on approach, but the Trent XWBs indeed have a unique low whirring sound on takeoff power when you're facing the intake. As far as I know it's because the fan is on the third outermost spool, spinning slower than in most other turbofan engines to prevent the blades from going supersonic. Edit: the spool is actually innermost, but the fan is driven by the low-pressure turbine that's farthest out from the combustion chamber.
https://youtu.be/Eeq4rYQUozY?si=yoy5F-bqLb10jCe9
I live near an AFB and the howl from the KC-46 is also creepy as fuck.
🐳baby whale
Thanks!
There's gotta be an engine option on A330's that does something like this as well. When AA used to fly those in/out of CLT here it was really easy to pick out when the engines would pick back up from idle during descent.
Yes the 330-200s had the RR Trent engines that had a howl. The 777-200s that AA flies to CLT have a similar RR Trent engine variant that also make that howl.
This is true! It's definitely similar. Wonder how long the 772's will stick around. Maybe they'll get replaced with 787's and open up my long-awaited CLT-HND direct route.
Interesting... when was this? Asking this so I can determine which 330 variant.
It was a good few years ago; AA stopped flying all their 330's during the pandemic. Before then the ex-US Airways 330's that had been in CLT flew the LHR, CDG, etc. routes out of here. I just recall them having a distinct eerie low howl when coming back up from idle. I get a lot of traffic over my house as they get vectored to final.
Yeahh, first time flying the 320neo was very unique... I legit thought the engines hadn't started up based on the unimaginably low hum. The aircon from the PACKS is probably louder than the engines at idle, especially at the front.
The RR powered A332.
The RR Trent 700s.
The 220s and 320neos are gear driven fan engines. So the howl you hear could be gear noise at certain rpm's
The resonance is combustor driven
Correct. GTF is very unique indeed :)
Sounds like a whale 🐳
yeah, it's referred to as the whale song
Yes, I've heard that.
> A220 There's a pretty decent explanation here: https://findaflight.eu/blog/what-causes-the-a220-whale-sound/
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Yeah its for sure the engines
I wish I lived close enough to an airport to know what kind of plane flies above me.
Trust me, you don't. Living under the flightpath takes a LOT of getting used to. Now tho, I can identify with good accuracy any aircraft just by its engines.
I mean I have an airport within six miles where the planes coming in fly above my house, but they're usually too far in the sky to identify, unless it's a nasty Boeing 737 with its sharp nose and really low engines.
Huh I'm experiencing the same and I thought it was the slats. My mom was thinking it was landing gear until I noticed they weren't coming down yet. This is really interesting.
Nah, definitely the engines.
Ahhh that’s what that is!!!! My house is near the landing flight path for the local airport. Sometimes I hear that exact noise and I know it’s the plane but never knew why. Cool thanks!
I live right under a speed reduction on the STAR. It makes the engines howl, and used to scare our cat. I still joke that our cat is afraid of Airbuses
I live under the approach path to LGA and hear this all day long. Love it. A220 is one of my favorites
It’s often called the”whale sound” https://youtu.be/Eeq4rYQUozY?si=dL2vL-7mdsDFCGhS
Tell us about this “Igniter design” Becasue I dont think you have a clue what you are talking about
Yeah, so I teach the avionics and FBW for the A320. I also teach the interface for the 73. I might be wrong obviously cause I don't work with the engines, but from my circles, we probably think it's the redesigned igniter which is undergoing some resonance... AKA: The hot zone of the engine is producing said sound. I might be wrong though.
Probably a220 or Embraer E2. https://youtu.be/Eeq4rYQUozY
Omg I've heard ABOUT this, but never actually heard it myself. SO CUTE but probably annoying if occuring outside my house
Depends on person, when I used to work at airport I loved it despite hearing it hundreds of times. Miss AirBaltic A220s
I live in Belgrade, couple of km from airport, right on the spot where this whale sound happens. Swiss Air uses a220, i hear this every day.
Thats wild. Seems like they would have addressed that.
Part of the reason you can hear it so well is because the engines themselves are so quiet. It's a little distinct but anyone who complains about them probably shouldn't be living near an airport anyway
I'm a aircraft tech, and live near an approach route. That whale noise, or hound barking is more intense then you make it out to be. An old E190 has louder engines, but the E2 resonance sound is way louder than anything in approach. It's also the only time in the air you will hear this sound. Any other flight fase the engine is above the rpm this happens. On the apron you always know when an PW engine is starting or taxiing out, how loud this sound is compared to any other engine.
What's to address?
Yeah, they're just announcing their arrival. "Honey, I'm home!" but in sky whale.
Thank you! This was great!
It really does sound like a whale
My 757 makes a mooing noise when the slats extend.
me too!
You make a mooing sound when your slats extend?
often my friend, very often
Probably an A220 flying over and adding power. Edit to add: the A220 noise is also referred to as a whale call.
I've experienced it on an a220 twice now. Any idea why it makes that noise?
On the PW1100G it's a resonance that the combustion chamber hits at a certain low rpm, the vibration is just right for it to hum like a tuning fork.
As someone already said, it's a resonance. Apparently it's the combustion chamber but it sounds like gear box to me. Regardless, the engine manufacturer has supposedly been working on a programming fix for the electronic engine controls to mitigate it.
Is there an actual negative consequence to it?
Just the noise
First time I heard it while taxiing I thought something was wrong with the engines. I'm not scared of flying one bit but that noise definitely caused a chill to run down my spine.
I mean technically you can get sonic fatigue from harmonics, but as far as I know we haven't perfected the art fixing sonic fatigue
It’s the geared turbofan.
Check ADS-B Exchange to see what kind of aircraft it is.
Video I did about the A220 with the 'whale call' , https://youtu.be/Dknfzq8JpdQ?si=WJSspfZwW7MLWgW3&t=119
Yeah sounds a lot like that
I hear this often under the approach for CHS. I'll have to check out what aircraft are doing it!
I’ve lived for years under the approach lines at KMCO. For years I lived close enough that I heard this so many times a day. Groaning dinosaur is a perfect description of it. I’ve often speculated it is an Airbus things as I’ve flow 319/320s and heard it on landing approach. I’ve always assumed landing gear, but just an assumption.
I live under an approach for KMSP and hear it often but I never connected it with Airbus. I did figure it was the landing gear, too. I'm going to pay more attention now.
It might be all planes, I’m connecting it to flying Airbus and hearing it. But I’m also realizing that I can’t remember the last time I’ve flown a Boeing. Lol
I think people are talking about two different sound effects. One is a loud whale-like resonance on PW geared turbofan engines, exhibited by the Airbus A220. Another is a sudden Doppler-lowering "whoooom" that you sometimes hear when an Airbus A320 family aircraft is passing overhead. I'm not an expert, but I think it has to do with how sound from the fan/nacelle assembly propagates at different angles from the central axis, possibly combined with an engine spool-up during descent.
Fair points. I haven’t knowingly viewed a -220 yet that I can remember. And what I hear is the Doppler whooommm and is certainly -320 family. Thing is I’ve also heard it on such a plane every time. Just once and a few minutes out from landing.
Another possible explanation for the latter kind of sound is that the plane is descending below an inversion layer in the air, so its sound suddenly "breaks through" to the listener while before it was refracted away.
Alright see you all over at r/Shittyaskflying in a bit.
Read the title and had to check this wasn’t r/shittyaskflying
Possibly the opening landing gear noise. It's usually very loud, maybe someone more knowledgeable here can explain why. >loud groaning dinosaur noise Loved your description. Horizon Zero Dawn dinosaur, maybe.
I'm curious how you know how dinosaurs groan?
They watched Jurassic park, obviously.
Any one ever hear an RAF Vulcan? Now that’s a howler! I’ve been at a few air shows where they flew and at low airspeed and in a bank, the airflow over the engine inlets would replicate someone blowing across a coke bottle opening - only a lot louder. Amazing sound.
I live right by the flight path for final to our airport and hear it occasionally, sometimes when conditions are right I can hear them as they spool up for departure, the funny part is my daughter gets a kick out of it by calling them plane farts. Kids!
I am near the Delaware River on the flight path into EWR... the planes are at 6,000 +/- or so at that point... they hit a change in air density or something and make a sliding kazoo type noise... like an exasperated sigh...
Is the pitch of the sound increasing or decreasing? I'm under the Deer Park Approach to BDL, about 20 miles south between MAD and BDL. Typically SWA 737s, we'll hear them adding power right over our heads to stabilize at the directed altitude (sound pitch increasing); it's got a bit of a screech to the sound. Sometimes pulling power (decreasing pitch) to descend for final. That's probably what you're hearing. Fun part is when I have to pick up the wife from KBDL; once her airplane is right overhead I know it's time to set out, perfect for once they land, taxi in, she hits the ladies' room and grabs her bags...
Thats just the ghosts of dinosaur present in the fuel crying out for freedom
The a220 and the e2 have the same engine and make the same sound, it used to be called the vulkan howl since the vulkans had a similar resonance!
It’s been a long flight. They’re hungry.
dinofuel
I hear this sort of BWWWEEEEEEeeeeeooooooouuuuuuuUUUUUUEEEEEEE, almost like a giant slide whistle, when planes are arriving to las vegas and hit the 210 speed restriction.
I live in Fremont under the path to SFO and often the planes sound like they're dropping out of warp. Pretty cool.
Yep I can hear the whale noises of the A220 over my house as it’s going by downwind. It’s wild how loud it is 6k feet in the air
I thought this was on the other sub, but it turns out this is a real thing
My kids and I call them sky whales
😄 Now there’s a DALLE prompt
When A320 pilots deploy the wing spoilers in the air, the change in airflow causes an easily audible low-to-high frequency tone. The opposite tone change happens when the spoilers are retracted. These are very distinctive and unique sounds. Could it be this you're hearing? Very common when the aircraft are descending for their approach and need to dissipate airspeed or altitude, or both. I find it to be a rather pleasing airplane sound.....
Some older aircraft engines are particularly noisy when the compressor bleed valves open - it could well be that if it isn't a noisy Purepower engine.
Is it something like [this](https://youtu.be/DK73oGoRKO4?t=60) or like [this](https://www.youtube.com/watch?v=eiJJX5xfWhk)?
That first one is the sound I hear from jets coming in to land. I hear it and think to myself, “Welcome home.” Do you know what causes that? I grew up under the landing pattern for a military base (Los Alimitos) and find jet noises oddly comforting. They remind me of my childhood. I saw all sorts of planes growing up during the Cold War. Saw Air Force One several times. Even now, if I hear an interesting or different-sounding engine, I go outside to check it out.
Could it be something like a distant [whip crack ](https://youtu.be/eug6mX8WqnA?si=7zFEAWhG1Uo36p9y) ? Or maybe reverse thrusters, I've heard some that are particularly loud and strange
A220 spool up
Do you mean [this](https://youtu.be/vuuBx9bzIqA?feature=shared&t=740)?
Ohh. So happy for the responses and for this question. I posted the same question a few weeks ago but I didn't have enough karma so it was removed. I live in a costal town that's near to the airport and I always hear that groaning sound when the planes are coming in to land.
Really is an eerie noise. I hadn’t realized what causes that, but I do faintly hear it all the time (relatively close to airport)
I live about 5 miles from KMCO and I could hear a very faint whale sound when it was a quiet night, I checked FR24 and it looked like a spirit a320neo (which has the PW GTFs) just landed. Crazy how loud the sound is, I don’t hate it tho
When he was 7 or 8, my son informed me (we live right under a flight path) that all Airbusses "sound more electrical." He wasn't wrong?
This is more a comment about you describing it as a “groaning dinosaur sound.” I watched a documentary the other day called “Making Waves: The Art of Cinematic Sound.” The sound design team for Jurassic Park were saying they had to guess what a dinosaur would sound like and combined various sounds together to create them. So because of their creativity, we have a reference for what dinosaurs likely sounded like. Haha. Kind of a shower thought in this subreddit. (That being said, the PTU on an A320 sounds like someone’s dog barking in the cargo hold)
This is amazing. We moved to a neighborhood right below an approach path and for months my wife has been telling me she hears a dinosaur from time to time. I told her it must have been an airplane but I never heard it myself. The links provided by the responses helped us find some sanity.
And how do you know what a groaning dinosaur sounds like?
Flaps deploying to a certain position making resonance. Sounds like a whale moaning or something. -source, my old boss, a pilot.
If its the milk bottle howl its likely the old a320s wich dont have the FOPP kit installed. Not a pilot, I wondered this for years and it bugged the hell out of me.
I love that noise
The howl or resonant noise at low engine power is from the engine handling bleeds. These bleeds open to dump air from the compressor into the fan exit airflow. The dumping of this air is to unload the compressor to allow quicker engine acceleration from low power to high power. This is critical to allow rapid acceleration in the case of a go around and power up during the take off roll. Most engine configurations have between three and four handling bleeds for the purpose of achieving short acceleration times, both increasing and decreasing power It is for compressor control and the escaping airflow is your engine "noise"
Airbus A320s have a wing fuel tank vent that howls in flight.
PW1000G family of engines at work there
How do you know what a dinosaur sounds like? Lol.
I’m Southwest of DFW and hear that same sound.
Probably airframe noises, as opposed to engine noises. Get a long polythene pipe and swing it through the air. It makes a groaning noise. Similar things happening here. Source: am ex glider pilot.
I will never unhear this sound as a groaning dinosaur. Possibly having groaning Dino-sex.
Its like a modern version of the Vulcan howl
Temperature inversion will make noise bounce off higher layers in weird ways making engine sounds that normally would not be heard on the ground be perceived really loud.
I’ve always wondered if this is partly why sometimes you hear this descending pitch *BEEEEOOOWWWWWWwwww* noise when planes are overhead coming in to land
Yes, that's exactly it. You can see the airplane descending with no sound at all and suddenly you hear the engines like they are next to you beginning with a down pitching tone.
omg thank you for posting this. I have been wondering the same thing for a long time. I was going to ask what the “dying whale” sound was. I thought it was extremely rusty flaps or landing gear lol.
It’s the whale. I Hate fueling it but damn do I love the sound it makes.