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Comment by dandelany | Hacker News Reader

Yes! My favorite example of this is the sound made by the space shuttle's solid rocket boosters at liftoff. Techies who have seen recordings of shuttle launches generally assume the guttural crackling, popping roar sound they hear is due to a badly adjusted microphone clipping the loud sounds. In fact, this was a physical phenomenon that could be heard in real life, due to the pressure waves physically "clipping" against a vacuum upon reaching the atmospheric pressure limit! Sorry I can't seem to find any better sources, but this is an anecdote I've heard from several witnesses: http://forums.prosoundweb.com/index.php?topic=98023.25;wap2

Here's a good example of the sound I'm talking about: https://www.youtube.com/watch?v=OnoNITE-CLc&t=1m44s

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I had the privilege of watching STS-134 launch from the press site and everyone tells you: "it's loud. louder than loud. you will be surprised by how loud it was." and that still wasn't enough to prepare me. It is loud. It is literally like the sound is clipping, the brapping noise moves through your teeth, it vibrates your clothes, you feel it inside of you. It is incredible, and I was so lucky to have watched it from the closest any humans are allowed to be (except for the brave rescue team in an APC 1 mile away).

I recall being thrilled to be able to see STS-124 in May 2008, only because the previous launch had been delayed, and the new date coincided with our holiday. Among other things it was taking up parts to fix a toilet on the ISS!

I remember also being struck by not only how loud it was, but also how bright. It's something that photos or video just can't capture.

I was at the STS-135 launch, and both the sound and brightness of the main engines surprised me.

Wow! That sounds like an amazing experience. Kind of a dumb question, but were you also impressed by how fast it goes up, or does it 'float' into the sky?

Well, except for the suckers sitting atop the stack of course...

Yesss! I got to see STS-3 (!!!) from the press site. I was just a kid at the time on a school field trip. Our bus was misdirected to the VIP/press site, and they let us stay.. ;-) IIRC, several of the huge rental-only Canon telephoto lenses were in attendance on the photog's hill. The photographers were incredibly cool, talking with us, letting us look through their spotting telescopes and such.

The launch was far and away the loudest phenomenon I've ever heard, or ever hope to hear. Impossible to adequately describe. You don't hear the sound, you are the sound. The universe transforms, and is made of nothing but sound and vibration.

Is this brap noise like "cavitation" you get from propellors in water?

Previous HN discussion about shuttle launches, with a very entertaining essay by Penn and Teller https://news.ycombinator.com/item?id=2793404

As if, at that level, the air bangs against itself """like""" a solid ?

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