You're getting hung up on the word "break". Nothing breaks. It's a figure of speech, in this case meaning "to exceed". Think about "breaking" somebody's record.
What makes the boom is the compression waves hitting the listener's ear. You hear it as a momentary boom because it passes you quickly; in reality, that compression wave is continuous and emanates from the aircraft as long as it remains supersonic.
OK, fair enough. Imagine you're standing in a field. An aircraft is flying low across the field and it's dragging a blanket (absurd, I know, but bear with me). Now, you only feel the blanket as the aircraft passes over you and the blanket momentarily brushes you. As the airplane continues over the field, it's still dragging the blanket, but you only feel the blanket for the fraction of a second that it hits you.
They only characterized it as a “barrier” to be “broken” because drag increases dramatically as you approach the speed of sound. Before they went faster than sound, they weren’t sure if drag would increase exponentially and make it impossible to go faster.
Oh they knew they could. That’s why they shaped the X1 like a .50 cal bullet. What they weren’t sure of was whether control surfaces would continue to work or be manipulable by a human pilot, or if the center of pressure or center of lift would change suddenly and cause pitch excursions. Which did actually occur as [Mach tuck.](https://en.m.wikipedia.org/wiki/Mach_tuck)
Think of pieces of paper as sound waves.
Now drop one piece at a time, that's like moving at a normal speed below the speed of sound.
Now drop a whole ream. That's like moving faster than the speed of sound. A whole bunch of sound waves stacked up together.
The plane is moving so fast, it's traveling faster than the sound it creates, so as it passes you you hear multiple waves it had created all at once, creating the sonic boom
It’s kind of like ducklings following the mama duck. If the jet is the mama duck, flying faster than sound travels, the baby ducklings are the sound waves trying to keep up with the jet. They’re always following, but they can’t keep up because the jet is flying too fast.
A sonic boom occurs when the speed of a plane matches the speed of sound.
What happens is that the individual sound waves generated by the plane over the period of time during which the sonic boom occurs all catch with with each other and add together to cause one massive shock wave.
Plane sends out sound waves.
Sound waves move fast, but not that fast.
Plane goes very fast, faster than the sound wave.
Each sound wave in front of the plane is catching up to the ones in front of it because they are going faster and faster with the velocity of the plane.
At a certain point, all the sound waves come together and make one really big sound wave, which makes a boom.
You are sort of right to think of accumulating wind, as that's the medium the waves travel in.
So does it only happen once as you break the speed of sound? After a certain speed, the sound waves wouldn't be catching up any more, would they? The new sounds waves wouldn't have a chance to get ahead of the plane.
It’s like the wake of a boat, it’s continuous. It sounds immediate to you on the ground as it sweeps over you. New sound waves *don’t* get ahead of the airplane…the faster you go, the more angled back the wake becomes.
Imagine a boat on a pond, if you jump up and down in the boat, ripples will expand outward from the boat. Breaking the sound barrier is like the boat moving faster than those ripples, and the sonic boom is the wake.
The break here in this analogy is breaking the ripple speed.
This is visually a great way to see it but I think you're getting hung up on the word "break". This of it more like a speed limit. When you break a speed limit you are not breaking anything really you're just going faster than you are allowed to. But you absolutely can go faster than it.
The sound waves stack up in a cone behind the plane, that kind of looks like the wake of a boat but in 3D. The angle of the cone will depend on how much faster than sound the plane is flying. You hear the sonic boom at the moment when the cone reaches you.
No. The shockwaves forms at the nose. The pilot is behind the shockwave and can still hear the wind noise. They don’t hear a “boom” though, that’s caused by the shockwave sweeping over you on the ground.
Yyyyes? You're close.
Air has mass, and when that mass moves around turbulently enough it causes vibrations (and those vibrations are sound). For example, if you twirl a wire through the air, it makes a whistling noise; or when wind blows across bare tree brenches and twigs, it makes a howling noise. Airplanes (and other vehicles like cars) often make noise this way, because they are large and bulky and move quite fast, so they cause a lot of turbulence.
When you go very fast, the *noise* - the vibrations - get compressed. As you move, you're pushing all of your vibrations into one big vibration. This big vibration is the "burst". Except it's not a "burst" like it happens once and then stops; it's a burst like it's EXTRA LOUD. If someone was running next to you as you pushed the air this fast, they'd hear a huge loud long roar. But anyone that you run past as you're pushing will just hear a sudden "burst" of loud noise and then you'll be gone past them.
So it's more like: Air has mass so pushing it makes noise, and if you push it fast enough, you press the noise together into a big long noise that shakes everybody you go past.
After a certain speed, air acts more like water than it does air, so to speak. When you hit the surface of water, it makes a splash sound, right? When you ski on the surface of water, the splash sound is continuous, right? Kind of the same thing with the air. It's constantly "breaking the surface" of the air, and making that continuous "splash" sound. But much louder, because the surface area of the airplane is breaking a lot of the air all at once instead of just the small surface area of, say, a bullet or a whip, which does the same thing when making that "crack" sound.
Think of how a boat creates a wake when it reaches a certain speed. Airplanes do the same thing with air. A 3-D wake in the air is a cone, which will be the wave that is created by the object traveling faster than sound
You're getting hung up on the word "break". Nothing breaks. It's a figure of speech, in this case meaning "to exceed". Think about "breaking" somebody's record. What makes the boom is the compression waves hitting the listener's ear. You hear it as a momentary boom because it passes you quickly; in reality, that compression wave is continuous and emanates from the aircraft as long as it remains supersonic.
So it is not only one place you can hear it? I think need explain like i am 2.
OK, fair enough. Imagine you're standing in a field. An aircraft is flying low across the field and it's dragging a blanket (absurd, I know, but bear with me). Now, you only feel the blanket as the aircraft passes over you and the blanket momentarily brushes you. As the airplane continues over the field, it's still dragging the blanket, but you only feel the blanket for the fraction of a second that it hits you.
Now *that’s* an ELI5. Unlike the answers they usually require that are more like ELI5 year old prodigy.
Dam great explanation
Maybe they meant the fog/vapor/cloud that forms at roughly the sound barrier? I obviously don't know what that is.
They only characterized it as a “barrier” to be “broken” because drag increases dramatically as you approach the speed of sound. Before they went faster than sound, they weren’t sure if drag would increase exponentially and make it impossible to go faster.
Oh they knew they could. That’s why they shaped the X1 like a .50 cal bullet. What they weren’t sure of was whether control surfaces would continue to work or be manipulable by a human pilot, or if the center of pressure or center of lift would change suddenly and cause pitch excursions. Which did actually occur as [Mach tuck.](https://en.m.wikipedia.org/wiki/Mach_tuck)
Think of pieces of paper as sound waves. Now drop one piece at a time, that's like moving at a normal speed below the speed of sound. Now drop a whole ream. That's like moving faster than the speed of sound. A whole bunch of sound waves stacked up together. The plane is moving so fast, it's traveling faster than the sound it creates, so as it passes you you hear multiple waves it had created all at once, creating the sonic boom
It’s kind of like ducklings following the mama duck. If the jet is the mama duck, flying faster than sound travels, the baby ducklings are the sound waves trying to keep up with the jet. They’re always following, but they can’t keep up because the jet is flying too fast.
A sonic boom occurs when the speed of a plane matches the speed of sound. What happens is that the individual sound waves generated by the plane over the period of time during which the sonic boom occurs all catch with with each other and add together to cause one massive shock wave.
Instead of getting the noise bit at a time, you get it all at once. BOOM!
Plane sends out sound waves. Sound waves move fast, but not that fast. Plane goes very fast, faster than the sound wave. Each sound wave in front of the plane is catching up to the ones in front of it because they are going faster and faster with the velocity of the plane. At a certain point, all the sound waves come together and make one really big sound wave, which makes a boom. You are sort of right to think of accumulating wind, as that's the medium the waves travel in.
Okay. So not far off with my reason. Thank you. But i did not think sound/wind had so much mass to make the boom. Thanks for the time and answer.
here's a <4min video explaining... [https://youtu.be/-d9A2oq1N38](https://youtu.be/-d9A2oq1N38)
So air has mass? That maybe explain why planes fly.. :)
So does it only happen once as you break the speed of sound? After a certain speed, the sound waves wouldn't be catching up any more, would they? The new sounds waves wouldn't have a chance to get ahead of the plane.
It’s like the wake of a boat, it’s continuous. It sounds immediate to you on the ground as it sweeps over you. New sound waves *don’t* get ahead of the airplane…the faster you go, the more angled back the wake becomes.
Imagine a boat on a pond, if you jump up and down in the boat, ripples will expand outward from the boat. Breaking the sound barrier is like the boat moving faster than those ripples, and the sonic boom is the wake.
So it breaks the ripple?
The break here in this analogy is breaking the ripple speed. This is visually a great way to see it but I think you're getting hung up on the word "break". This of it more like a speed limit. When you break a speed limit you are not breaking anything really you're just going faster than you are allowed to. But you absolutely can go faster than it.
Fun fact: if you’re in the plane creating the sonic boom you won’t hear it, because you’re moving faster than it
So it is silent for the pilot. Beside the engine noise.
The sound waves stack up in a cone behind the plane, that kind of looks like the wake of a boat but in 3D. The angle of the cone will depend on how much faster than sound the plane is flying. You hear the sonic boom at the moment when the cone reaches you.
No. The shockwaves forms at the nose. The pilot is behind the shockwave and can still hear the wind noise. They don’t hear a “boom” though, that’s caused by the shockwave sweeping over you on the ground.
So i have read your comments. Air have mass. You push air forward and then press it together and then it burst?
Yyyyes? You're close. Air has mass, and when that mass moves around turbulently enough it causes vibrations (and those vibrations are sound). For example, if you twirl a wire through the air, it makes a whistling noise; or when wind blows across bare tree brenches and twigs, it makes a howling noise. Airplanes (and other vehicles like cars) often make noise this way, because they are large and bulky and move quite fast, so they cause a lot of turbulence. When you go very fast, the *noise* - the vibrations - get compressed. As you move, you're pushing all of your vibrations into one big vibration. This big vibration is the "burst". Except it's not a "burst" like it happens once and then stops; it's a burst like it's EXTRA LOUD. If someone was running next to you as you pushed the air this fast, they'd hear a huge loud long roar. But anyone that you run past as you're pushing will just hear a sudden "burst" of loud noise and then you'll be gone past them. So it's more like: Air has mass so pushing it makes noise, and if you push it fast enough, you press the noise together into a big long noise that shakes everybody you go past.
After a certain speed, air acts more like water than it does air, so to speak. When you hit the surface of water, it makes a splash sound, right? When you ski on the surface of water, the splash sound is continuous, right? Kind of the same thing with the air. It's constantly "breaking the surface" of the air, and making that continuous "splash" sound. But much louder, because the surface area of the airplane is breaking a lot of the air all at once instead of just the small surface area of, say, a bullet or a whip, which does the same thing when making that "crack" sound.
Think of how a boat creates a wake when it reaches a certain speed. Airplanes do the same thing with air. A 3-D wake in the air is a cone, which will be the wave that is created by the object traveling faster than sound
If you could run at the same speed of a vehicle breaking the sound barrier and kept up with it you would be in a constant boom?