
The 'war tubas' we used to spot warplanes before radar (2018) - Tomte
https://edition.cnn.com/style/article/war-sound-locators-before-radar/index.html
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ChuckMcM
Now I want to hear "Minuet in G for War Tuba" :-)

One of the more interesting things about sailing on Lake Mead outside of Las
Vegas was that when conditions were right you could hear people talking on the
beach more than a mile away. That you could weaponize this phenomena seems
pretty obvious in hindsight.

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cbanek
I love how sound carries over water. As a child, I used to sit on a dock on a
small lake, and I could see the beach somewhere between half a mile and a mile
away, and they would play volleyball. I could hear each noise as the ball was
bumped, noticing how the sound was delayed after the viewing of the ball hit.
I was totally amazed thinking, "I've just noticed the difference between the
speed of light and the speed of sound."

Good times.

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Aardwolf
Any idea why they're all pointed in the same direction, rather than different
directions, in photo 4/10?

[https://dynaimage.cdn.cnn.com/cnn/q_auto,w_1100,c_fill,g_aut...](https://dynaimage.cdn.cnn.com/cnn/q_auto,w_1100,c_fill,g_auto/http%3A%2F%2Fcdn.cnn.com%2Fcnnnext%2Fdam%2Fassets%2F181206101633-gettyimages-3224743.jpg)

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usrusr
You don't want to scan two angles at once. Direction is determined by probing
different angles, not by the difference between two angles.

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anamexis
From the article, it seems like the four horns on each individual unit are
enough to do the triangulation.

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Sosh101
Would this still work for modern military aircraft? I wonder if this + machine
learning might still be useful, given radar stealth.

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nephrite
Many of modern aircraft is supersonic so acoustic detection would be useless,
even if it technically works.

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Sosh101
True (though stealth bombers are subsonic, just). What about headings that are
not straight at you though? May still have value detecting things passing by?

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Ididntdothis
When I was at military I attended a few exercises where jets were involved.
They don’t go supersonic but pretty close to it so usually once you start
hearing something it’s almost over. It’s actually quite terrifying to have a
jet coming at you at 800 km/h at low altitude. Very surprising, then very loud
and incredibly fast. You also hear passing by jets only once they are long
gone. I assume radar is just much better than sound.

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jacquesm
Not just jets, a regular propeller based plane can have that effect:

[https://www.youtube.com/watch?v=4iOoiEbtf2w](https://www.youtube.com/watch?v=4iOoiEbtf2w)

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Ididntdothis
Now double or triple the speed, make it much louder and you have a jet.

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_sbrk
One of my favorite bands has the wearable-size version on the cover of an
album.

[https://en.m.wikipedia.org/wiki/Hello_World_(Information_Soc...](https://en.m.wikipedia.org/wiki/Hello_World_\(Information_Society_album\))

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simonsarris
When I played Bioshock Infinite (2013) I had wondered if the Boys of Silence
were conceived based on this idea.

[https://bioshock.fandom.com/wiki/Boy_of_Silence](https://bioshock.fandom.com/wiki/Boy_of_Silence)

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peter_d_sherman
These structures might very well have non-military (peaceful) applications for
physics experiments involving sound...

Sort of like what observatories are to light... these structures might be to
sound...

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dylan604
I'm kind of disappointed I have never seen these in any movies before. I'm
thinking they would have specifically gone well with the recent Man In High
Castle series.

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autokad
very interesting. still could be useful against drones, especially as drones
get used more and more in espionage and reconnaissance

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inscartwheelies
The next iteration, sound mirrors, were featured on Tom Scott.

[https://youtu.be/04F5osXK4vw](https://youtu.be/04F5osXK4vw)

