• We’re currently investigating an issue related to the forum theme and styling that is impacting page layout and visual formatting. The problem has been identified, and we are actively working on a resolution. There is no impact to user data or functionality, this is strictly a front-end display issue. We’ll post an update once the fix has been deployed. Thanks for your patience while we get this sorted.

Sonic Boom

fjmeat

fjmeat

Diamond Member
Dopplereffectsourcemovingrightatmach1.4.gif


But the boom comes before the Jet passing over? Video: http://youtu.be/kMtjpDykp9k
 
The video is probably not synced properly.

Also I'm not convinced that was a sonic boom. Jets are fucking loud and just because it CAN fly supersonic, doesn't mean it WAS flying supersonic.
 
Audio/video not synced up and that was definitely NOT a sonic boom.

If it was a sonic boom those car windows would have been shattered and those poor people's ears would probably be bleeding.
 
Crusty said:
Audio/video not synced up and that was definitely NOT a sonic boom.

If it was a sonic boom those car windows would have been shattered and those poor people's ears would probably be bleeding.
Click to expand...

My thought too. At the air show, the announcer always says the jets cant fly fast enough in a public area to create the boom. The crowd would go hysterical. But they can however, do it over the ocean. Won't that upset the shippers?
 
I have been around 1 sonic boom and it was when I was fishing in MN. It sounded like an explosion. I never heard it again and I stayed whole summers on that lake. I don't know about shattering windows but it was pretty damn loud.
 
Jeffg010 said:
I have been around 1 sonic boom and it was when I was fishing in MN. It sounded like an explosion. I never heard it again and I stayed whole summers on that lake. I don't know about shattering windows but it was pretty damn loud.
Click to expand...

At 50' in the air it would definitely shatter those windows.
 
Train said:
lolno
Click to expand...

Every resource I've looked at puts sonic booms at 200+ decibels, some even say it approaches 215dB.

Ear drums rupture at less than 200dB and most glass breaks somewhere below 185dB.

At 50' in the air, like the plane was in the video, I stand by my statement saying that a sonic boom would shatter those windows and rupture their eardrums.
 
At the Oshkosh airshow they used to have a prop plane fly over that had propeller tips that would exceed the speed of sound such that it was continuously farting out little sonic booms. It was loud.
 
Crusty said:
Every resource I've looked at puts sonic booms at 200+ decibels, some even say it approaches 215dB.

Ear drums rupture at less than 200dB and most glass breaks somewhere below 185dB.

At 50' in the air, like the plane was in the video, I stand by my statement saying that a sonic boom would shatter those windows and rupture their eardrums.
Click to expand...

I think your estimates are way off. Myth busters had Blue Angels fly as low as possible and could barely break the weakest of glass. Car windows are one of the toughest forms of glass, they ain't gonna break due to noise. Else anyone who parks near a fireworks show would have their windows blown out.

And ears bleeding? GTFO
 
Train said:
I think your estimates are way off. Myth busters had Blue Angels fly as low as possible and could barely break the weakest of glass. Car windows are one of the toughest forms of glass, they ain't gonna break due to noise. Else anyone who parks near a fireworks show would have their windows blown out.

And ears bleeding? GTFO
Click to expand...

Your car is a lot further away from fireworks shooting off than the car in the video is from the plane.

Did you even watch the video?

As far as the mythbusters episode goes... well it's mythbusters and their 'experiments' are hardly scientific.

Quote from the wiki page about the episode

Jamie set up a test area filled with various glass items and products while Adam performed a flyby in an F/A-18 going supersonic. However, at flybys of 8,000, 2,000, and 500 feet (2,400, 610, and 150 m), the jet failed to break any of the glass. They then performed a series of low altitude flybys at 200 feet (61 m), but only managed to break a single window. Since the majority of the glass was still intact, the MythBusters declared the myth busted.
Click to expand...

That is at 200', the jet in the video is still lower than that.
 
Crusty said:
Your car is a lot further away from fireworks shooting off than the car in the video is from the plane.

Did you even watch the video?

As far as the mythbusters episode goes... well it's mythbusters and their 'experiments' are hardly scientific.

Quote from the wiki page about the episode


That is at 200', the jet in the video is still lower than that.
Click to expand...

Ok, so find me a sonic boom that DOES break a car window. We'll call that scientific.

Considering planes have been breaking the sound barrier for a good 70 or so years, you'd think there would be evidence of this.
 
Train said:
I think your estimates are way off. Myth busters had Blue Angels fly as low as possible and could barely break the weakest of glass. Car windows are one of the toughest forms of glass, they ain't gonna break due to noise. Else anyone who parks near a fireworks show would have their windows blown out.

And ears bleeding? GTFO
Click to expand...

At low altitudes they probably aren't exceeding the speed of sound.
 
Train said:
Ok, so find me a sonic boom that DOES break a car window. We'll call that scientific.

Considering planes have been breaking the sound barrier for a good 70 or so years, you'd think there would be evidence of this.
Click to expand...

breaking the sound barrier, yes. breaking the sound barrier at 50' above populated areas with glass to break? no.
 
Last edited:
Train said:
Ok, so find me a sonic boom that DOES break a car window. We'll call that scientific.

Considering planes have been breaking the sound barrier for a good 70 or so years, you'd think there would be evidence of this.
Click to expand...

You keep on ignoring the fact that this plane in the video is extremely close to the ground.

TBH I would be very surprised if there was ever a plane that broke the sound barrier at 50' in the air directly over a car, let alone just 50' in the air. I'm sure there would be quite a lot of stress on the plane.
 
Crusty said:
You keep on ignoring the fact that this plane in the video is extremely close to the ground.

TBH I would be very surprised if there was ever a plane that broke the sound barrier at 50' in the air directly over a car, let alone just 50' in the air. I'm sure there would be quite a lot of stress on the plane.
Click to expand...

I'm not ignoring it at all, but even from 200 to 50 feet your not gaining many DB's on the ground. Interesting formula here: http://answers.yahoo.com/question/index?qid=20100306143514AAIt9hb

decibels on ground assuming 200 db boom:
200 - (20log(Height in Meters) + 11)

at 200 feet, you'd get 106.8 db, on the ground.

at 50 feet, you'd only have 134.5 db

Neither of which will put a crack in auto glass. Hell you can get car stereos to put out 150+
 
Train said:
They were INTENTIONALLY exceeding the speed of sound.
Click to expand...

It's not easy for any aircraft to get over M1 at 200'. Were they over it for the whole flyby, by how much?

Booms will vary a bit according to weather, type, size, speed of the aircraft. The window's susceptibility will vary depending on its properties as well as it's orientation to the boom, the surrounding land, etc.

I don't trust mythbusters at all.
 
That's an old Sukhoi SU-24M "Fencer". Between 0:17 and 0:19 you can hear the man exclaim "Sukhoi". It's definitely subsonic as it looks to be traveling about 300-350mph. The sound is created by air being drawn into the large rectangular engine intakes at very high velocity, which for the relatively low speed he's traveling at would be extremely loud for several hundred yards in front of the aircraft.
 
You must log in or register to reply here.

TRENDING THREADS

Back
Top