BREAK THE SOUND BARRIER

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crazyed

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My son and I both felt like we heard the sound barrier pop today, it was seeing a "bullet" launch off the pad and seemed like just prior to motor burnout the"blast/pop" happened"shocking" everyone. The speed of sound is flippin fast when you see it before your eyes. The blast was like a 12gauge shot gun "bang" In a stop motion pic off my vid there is a what looks like a 3ft long trail of mach diamonds a bit blurred and i will post when i can get it edited out..
I would like to hear about other accounts similar and info on how to build- what motors to use- etc... from the smallest motor and rocket and up
Can you get that bang off a G64W motor?
An E or F motor. ???
Also altitudes ,,How low can you keep it and still break the barrier? Audibly
Thx
Ed
 
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Yeah, you can't hear a Rocket Sonic Boom.
This Thread has been done before.
 
No Boom but I watched a documentary once where they were trying to generate lightning with small mim. Diameter rockets and it worked. I don't remember if the rockets were metal but it only makes sence that they where. Has anyone else seen it or know about it?
 
No Boom but I watched a documentary once where they were trying to generate lightning with small mim. Diameter rockets and it worked. I don't remember if the rockets were metal but it only makes sence that they where. Has anyone else seen it or know about it?

I started a Thread about Lightning Inducing Rocketry awhile back, I'll go find the Link for you. It's apparently easier than it looks, but ofcourse quite Dangerous.

https://www.rocketryforum.com/showthread.php?69016-Rocket-Induced-Lightning!
 
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I remember something about an Arizona Uni doing research. They towed a wire that was to attract lightning but they found out that the ionized smoke trail was sometimes enough. Which is why it's not a good idea to fly rockets with a lightning storm anywhere in the area. Lightning bolts have been known to travel miles and remember, lightning doesn't strike from the cloud down, it starts from the earth up....
 
I remember something about an Arizona Uni doing research. They towed a wire that was to attract lightning but they found out that the ionized smoke trail was sometimes enough. Which is why it's not a good idea to fly rockets with a lightning storm anywhere in the area. Lightning bolts have been known to travel miles and remember, lightning doesn't strike from the cloud down, it starts from the earth up....

In the Thread I started asking about it, it turns out that the People that did/do it PROFESSIONALLY actually ignite the Rocket REMOTELY from the safety of a Bunker or some such.
It should be quite obvious that standing in the Middle of a Field with a Metal Rod attached to a Wire that is essentially attached to you during incliment Weather is a BAD IDEA.
A Friend of mine was Killed by Lightning while playing Softball and the Actual Storm was still Miles away. R.I.P. Amy.
 
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Yeah, you can't hear a Rocket Sonic Boom.
This Thread has been done before.

My first thought is it was a deployment event...referring to the shotgun sound of it. Or a something spit out the nozzle. However, I've hear many claim to hear the echo of a rocket sonic boom... some with video...
 
At MWP12 during the M engine drag race I distinctly heard several pops from the rockets as the ascended. I assumed these to be sonic booms, or more accurately echos of sonic booms. While I understand the the shockwave travels primarily perpendicular to the direction of travel, I would think that some of this energy would propagate in all directions including behind the vehicle. It's either that or the particular M that most of the flyers were using has a bit or a pop at or near burn out.
 
My first thought is it was a deployment event...referring to the shotgun sound of it. Or a something spit out the nozzle. However, I've hear many claim to hear the echo of a rocket sonic boom... some with video...

But, as explained earlier, its not possible to hear a sonic boom on the ground from a rocket in the air unless the rocket were traveling horizontally past you. Many mistakenly believe a sonic "boom" is a sound produced instantly like thunder. It isn't. It's the result of the change in air pressure as the shock wave passes you.

-- Roger
 
At MWP12 during the M engine drag race I distinctly heard several pops from the rockets as the ascended. I assumed these to be sonic booms, or more accurately echos of sonic booms. While I understand the the shockwave travels primarily perpendicular to the direction of travel, I would think that some of this energy would propagate in all directions including behind the vehicle. It's either that or the particular M that most of the flyers were using has a bit or a pop at or near burn out.

A sonic boom isn't a sound so it can't propagate back to the ground.

I witnessed quite a few shuttle launches, but never experienced a sonic boom until the orbiter glided overhead days later. The shuttle went much faster and was much larger than any of our rockets. If a sonic boom from one of our rockets could be heard on the ground, we would have heard them when the shuttles launched. (Someone out in the ocean, though, might have experienced a sonic boom from a shuttle launch as the rocket passed close to horizontally over head.)

-- Roger
 
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Sorry everyone.. Looks like from the info It wasnt the sound barrier popping. I can see how it must have been some kind of noise the motor itself made at burn-out. That I can understand. Thanks for all the response.
 
The best way to tell if a rocket breaks the sound barrier is: to look at the smoke trail.
When it gets a little squirrely behind the rocket and the rocket's path is still true.
Then you know it has passed through it.
Allot of people mistaken a rocket motor initial thrust spike as a sonic boom.... when really it isn't.

JD
 
or you could take a Schlieren picture of it in flight...

https://www.nasa.gov/centers/dryden/news/FactSheets/FS-033-DFRC_prt.htm
100924main_L-94-324.jpg


An interesting technique that uses the Sun as a light source and a telescope trained on that image. The plane flies through the light path from the Sun to the telescope and a movie camera slides the film as the plane passes to capture the changes in light intensity due to the air density changes.

The technique has been modernized for the digital photography age.
https://aviationweek.com/blog/shockwaves-and-beauty-supersonic-flight
b12c2228-7790-463d-a145-e9a33e645dfd.Full.jpg
 
My Norad popped very loud on an I motor, and we also thought it was a sonic boom. After reviewing the video, we can clearly see the motor pop. It was the motor pushing something out of the nozzle. I have a video of it that I'll try to post.
 
Loc Norad pops after launch: [video=youtube_share;e4ysKuKkh84]https://youtu.be/e4ysKuKkh84[/video]
 
I had a Rocket with a "Pop" too recently, thanks to the included "First Fire Jr. Igniters".
Definitely no Sonic Boom there!

[video=youtube;DK7iI3qqR94]https://www.youtube.com/watch?v=DK7iI3qqR94&feature=youtu.be[/video]

So after waiting, I replaced the Igniter with an "Estes Sonic Igniter".
Still no "Sonic Boom", but way better Ignition.

[video=youtube;FHFeGZLoORE]https://www.youtube.com/watch?v=FHFeGZLoORE[/video]
 
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Wow.....I had an Aerotech Mustang on an Aerotech G-80-13T with a loud pop while it was still on the launch rail not too long ago. The single use motor blew up and destroyed my rocket on it's first flight. Defective motor.....ticked me off. Had quite a bit of money in that rocket too. lol
 
At MWP12 during the M engine drag race I distinctly heard several pops from the rockets as the ascended. I assumed these to be sonic booms, or more accurately echos of sonic booms.
We flew those on M3100WTs. That motor is a very aggressive design, and as a result the gas flow velocity at the aft end of the motor (upstream of the nozzle entrance) is very high. If the grains aren't bonded very well into the liner, the aftmost casting tubes can be sucked into the flow and blown out the nozzle. The manufacturer recommended method is to install the grains from the aft end, ensuring that most of the glue ends up where it's needed most. I know that a few people didn't load them this way, so you may have heard their motors chucking casting tubes as they shut down.
 
Wow.....I had an Aerotech Mustang on an Aerotech G-80-13T with a loud pop while it was still on the launch rail not too long ago. The single use motor blew up and destroyed my rocket on it's first flight. Defective motor.....ticked me off. Had quite a bit of money in that rocket too. lol
Was that single use motor or reload?

I had a single use G-80 CATO and destroy the booster of my Cosmodrome Aerobee Hi and they sent me replacement motor.
 
I'm not even sure you could hear the sonic boom even if you were beside the rocket as it broke the sound barrier... Mythbusters did some test on this with bullets and it basically didn't even physically move light objects placed near the bullet path... the only time it broke stuff was when the 50 cal bullet grazed the objects.
 
I'm not even sure you could hear the sonic boom even if you were beside the rocket as it broke the sound barrier... Mythbusters did some test on this with bullets and it basically didn't even physically move light objects placed near the bullet path... the only time it broke stuff was when the 50 cal bullet grazed the objects.

I tried to research this when the discussion came up before, but I was only able to find general statements saying that the power or intesity of the sonic booms (two are produced, but usually they are perceived as one) depends primarily on the mass and speed of the vehicle with the shape having a more limited effect. The duration between the two booms, produced from the front and back of the vehicle, is related to the length and speed of the vehicle. But, I couldn't find anything more than those general statements (and probably wouldn't have understood the math if I had).

-- Roger
 
Maybe get Mythbusters to fire a Machbuster rocket horizontally and have observers downrange listen (but how would you do that safely??)
 
Maybe get Mythbusters to fire a Machbuster rocket horizontally and have observers downrange listen (but how would you do that safely??)

The idea of placing microphones (or, better, some sort of pressure sensor) on towers or whatever came up the last time we discussed this. But, I think it would be difficult to ensure the sensors are close enough.

Maybe firing the rocket on a wire like the Mythbusters did for the RPG versus bullet thing? Of course, that turned out challenging even with their resources.

-- Roger
 
how tall would that tower need to be? I don't think you could do it anywhere near the tallest building in the world...
 
how tall would that tower need to be? I don't think you could do it anywhere near the tallest building in the world...

The towers would have to be tall enough so that the sensors are located where the rocket will be traveling at more than the speed of sound when it passes.

-- Roger
 
Anyone still remember the Machbuster rocket? You know that rugged minimum diameter rocket that flew on a G80. To build such a tower it would need to be about 4000-5000 feet tall, much taller than the world's tallest building. Such a building would be built in an urban area if it ever got built so I doubt anyone would be allowed to launch anything near it.
 
Anyone still remember the Machbuster rocket? You know that rugged minimum diameter rocket that flew on a G80. To build such a tower it would need to be about 4000-5000 feet tall, much taller than the world's tallest building. Such a building would be built in an urban area if it ever got built so I doubt anyone would be allowed to launch anything near it.

Yes...I still have one. I almost lost it on an F motor.
Wild.
 
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