Speed of sound.Someone explain.

Foxholer

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So (Rightees) should remember to allow for the 'draw' effect on North to South holes and 'fade' effect on South to North ones! :ROFLMAO:
 

Ye Olde Boomer

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Concorde flew at twice the speed of sound but passengers on the plane would not hear the sonic boom as they were travelling faster than the speed of the sound thus leaving it behind.
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I regret never having flown on the Concorde. I bet that was really great.

Since September of 2001, air travel has been miserable.

It was more pleasant sixty years ago than it is now. I remember actually thinking that it was fun.

Back to the point, though, shouldn't plane speed be based on where the plane was , where the plane is, and how long it took to get there?
I don't understand how the speed of the airstream, working either with or against the plane, would matter.

It may have an effect on what we hear but not on how fast we're going. If the plane has a certain speed and sound has a certain speed, the speeds could be compared regardless of the impact on actual sound made or heard.
 

Kellfire

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.
I regret never having flown on the Concorde. I bet that was really great.

Since September of 2001, air travel has been miserable.

It was more pleasant sixty years ago than it is now. I remember actually thinking that it was fun.

Back to the point, though, shouldn't plane speed be based on where the plane was , where the plane is, and how long it took to get there?
I don't understand how the speed of the airstream, working either with or against the plane, would matter.

It may have an effect on what we hear but not on how fast we're going. If the plane has a certain speed and sound has a certain speed, the speeds could be compared regardless of the impact on actual sound made or heard.
A sonic boom only occurs in an atmosphere, not a vacuum. You must be travelling at Mach One relative to that atmosphere. If you’ve got a wind of 100mph directly behind you, pushing you forward, you need to reach Mach One plus that 100mph tailwind to get a sonic boom.
 

Kellfire

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.
I regret never having flown on the Concorde. I bet that was really great.

Since September of 2001, air travel has been miserable.

It was more pleasant sixty years ago than it is now. I remember actually thinking that it was fun.

Back to the point, though, shouldn't plane speed be based on where the plane was , where the plane is, and how long it took to get there?
I don't understand how the speed of the airstream, working either with or against the plane, would matter.

It may have an effect on what we hear but not on how fast we're going. If the plane has a certain speed and sound has a certain speed, the speeds could be compared regardless of the impact on actual sound made or heard.
Also, you won’t hear a sonic boom if you’re a passenger on the plane that made it because by definition you’re travelling faster than the sound you’ve just created so it can’t catch up to you.
 

Ye Olde Boomer

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A sonic boom only occurs in an atmosphere, not a vacuum. You must be travelling at Mach One relative to that atmosphere. If you’ve got a wind of 100mph directly behind you, pushing you forward, you need to reach Mach One plus that 100mph tailwind to get a sonic boom.

Thanks. That makes perfect sense, even to me.
Would have loved to ride in that Concorde, though.
 

Tashyboy

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Not if you are of any size you wouldn't. They had one at Brooklands and inside of it is tiny. Cattle class is bad, Concorde was worse.

A beautiful sight in the air though.

Was once in Devon on holiday and an air show was on. Anyway it flew over the air show on it's way to New York. Pilot put his " foot down" when he was over Wategate bay where I was chillin in me speedos. Sweet mother the sound was immense. Agree it looked gorgeous.
 

Piece

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You should be in my house when the QRF Typhoons scramble from Coningsby on emergency calls. The house literally shakes and the sound is phenomenal.

When the Farnborough airshow is on, sometimes the fighters fly low over my house. Once, there was a Eurofighter that skipped over our house twice. JFC! The immediate and intense sound...
 

Wolf

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When the Farnborough airshow is on, sometimes the fighters fly low over my house. Once, there was a Eurofighter when that skipped over our house twice. JFC! The immediate and intense sound...
Its insane isn't it, we get them over head most days, im actually sat kitchen niw eating and watching them but doing normal manoeuvres so not a lot of sound, but you know when they have scrambled to a call out, because the sound is awesome and everything shakes.

Most recently was that jet 2 debacle where they scrambled to escort the plane back to Stanstead, all the ornaments on front room windows sill fell of onto the floor, and my oldest lad came running out his room wondering why his PlayStation had started jumping up and down on his cabinet ?
 

Piece

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Its insane isn't it, we get them over head most days, im actually sat kitchen niw eating and watching them but doing normal manoeuvres so not a lot of sound, but you know when they have scrambled to a call out, because the sound is awesome and everything shakes.

Most recently was that jet 2 debacle where they scrambled to escort the plane back to Stanstead, all the ornaments on front room windows sill fell of onto the floor, and my oldest lad came running out his room wondering why his PlayStation had started jumping up and down on his cabinet ?

We also get Chinooks flying very low. One time there was a jeep swinging underneath one, nearly knocking my head off! :LOL:
 

Wolf

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We also get Chinooks flying very low. One time there was a jeep swinging underneath one, nearly knocking my head off! :LOL:
Bloody chinooks, the things are even bloody noisier when you're inside one. The pilots though very skilled people especially the chinook display team guys
 

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Used to play a society match at West Kent, which sits just behind Biggin Hill, on the Friday before the air show. Used to love seeing the jets scream down the valley. No one complained about the slow play as we all stopped & admired the free show. :)
 

NearHull

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A couple of years ago the BBMF Lanc flew over the course at display level ( before it suffered the engine fire), one of my pps said “is that a Spitfire! “ The other two didn’t even bother to look up. After 36 years in the light blue, I still search the skies when I hear an aircraft.
 
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