Sound on the ground

[2016parks]

I’m about 40 miles away from some major airports. Especially on a humid day, I can hear lots of planes passing overhead. Flightaware says many of them are at 15,000 to 20,000 feet. Does that seem right? How high would they have to be, before I wouldn't be able to hear them? 30,000 feet? 35,000?

[DaveReidUK]

Aircraft make noise at whatever height they fly :O

Whether that noise propagates all the way to the ground isn't just a question of how high they are - as you note, it also depends on atmospheric conditions.

But the most crucial consideration is the amount of ambient noise where the listener is located. Under the right conditions, you can often hear an aircraft even at FL350.

If you hear a flight overhead and want to know how high it it, tracking sites like FlightRadar24 will tell you.

[eckhard]

I grew up about 12 nm north of LHR and on a quiet Sunday morning one could hear Concorde taking off. We were nowhere near the flight path.

[treadigraph]

Anything contrailing over the top I can hear, a few miles to one side usually not. A few weeks ago I could clearly hear an A400 out of Brize and approaching 30000' - it was more or less overhead Gatwick, 14 miles to the south of me.

[El Bunto]

The only contrailler I haven't heard passing over was a U-2 at 'above FL600'. I couldn't see it either, just a very thin trail. Some of the big bizjets are hard to hear when they're up in the FL500 range.

Noisiest brutes are A330s climbing, I don't know why they make so much noise but they're identifiable from indoors or through overcast.

I was just thinking this morning of a late friend who used to watch Constellations and DC-6s thrumming overhead, barely clearing FL150.

[Espada III]

I was sitting in my garden last week on a quiet afternoon and realised I could hear an aircraft. I looked around and could see nothing near me, despite several routes almost overhead at low level arrriving into MAN which is about 11 miles away. So I looked further into the sky and there were two contrails, clearly at cruise level and they were the only thing near (confirmed by a quick look at FR24). So I assume that aircraft a 35,000ft can be heard easily under the right conditions.

Remember 35,000ft is about seven miles and I can hear aircraft taking off from MAN if the ambient sound is low.

[MATELO]

Aircraft make noise at whatever height they fly :O

Whether that noise propagates all the way to the ground isn't just a question of how high they are - as you note, it also depends on atmospheric conditions.

But the most crucial consideration is the amount of ambient noise where the listener is located. Under the right conditions, you can often hear an aircraft even at FL350.

If you hear a flight overhead and want to know how high it it, tracking sites like FlightRadar24 will tell you.

I would say higher than that. I get the emirates flight out of Glasgow hitting FL350 right over me most nights and I can hear it through closed windows and doors.

[LiamNCL]

I would say higher than that. I get the emirates flight out of Glasgow hitting FL350 right over me most nights and I can hear it through closed windows and doors.

Im in Newcastle and hear the GLA DXB evening 777 every night the same time and its usually around 35,000ft

[chevvron]

We live about 12 miles southwest of Heathrow and when easterly departures are in use, we can hear them 'opening up' for takeoff from 09R; there's sometimes also a bit of vibration too.

[MATELO]

Im in Newcastle and hear the GLA DXB evening 777 every night the same time and its usually around 35,000ft

Yup, thats where I am. Even Mrs MATELO who has no earthly interest in aircraft looks up and says "Glasgow - Dubai, Emirates" (normally just on 10pm :))

[Musket90]

Reminds me of the Air France Concorde JFK - CDG flight many years ago coming along the English Channel at 9-10 pm and hearing the distant sonic boom.
Consequently I think the point at which deceleration to subsonic occurred was changed to a location further west so people on the ground didn't hear it.

[Rob1975]

For some reason (anyone know?) A330's are quite a bit louder than others when at cruise altitude, I've found.

[dook]

Dave Reid is quite correct re. ambient noise.

I often hear aeroplanes cruising a route at high level almost above me.