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The 'war tubas' we used to spot warplanes before radar (2018)

edition.cnn.com

11–20 of 26 posts

Re: The 'war tubas' we used to spot warplanes before radar (2018)

#11
post #5
post #3

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

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

Most do not have supercruise, so they would spend most of their flight at high subsonic speeds.

Re: The 'war tubas' we used to spot warplanes before radar (2018)

#12
post #3

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

Detecting helicopters would be one situation where it could be useful for mobile troops on the ground.

Re: The 'war tubas' we used to spot warplanes before radar (2018)

#13
post #11
post #5

Earlier quoted context omitted.

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

Most do not have supercruise, so they would spend most of their flight at high subsonic speeds.

Then it becomes a battle between the detection range of the audio sensors vs how long the attacking craft can spend supersonic. They could spend the last phase of the approach supersonic and even transition then turn to make any tracking useless.

Re: The 'war tubas' we used to spot warplanes before radar (2018)

#14
post #7

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...

Looks like San Francisco, so I assume it's an exercise and perhaps they're all tracking the same friendly plane.

Re: The 'war tubas' we used to spot warplanes before radar (2018)

#16
post #6
post #5

Earlier quoted context omitted.

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

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?

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.

Re: The 'war tubas' we used to spot warplanes before radar (2018)

#17
post #8
post #7

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...

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

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

Re: The 'war tubas' we used to spot warplanes before radar (2018)

#19
post #6

Earlier quoted context omitted.

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?

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 bette…

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

https://www.youtube.com/watch?v=4iOoiEbtf2w

Re: The 'war tubas' we used to spot warplanes before radar (2018)

#20
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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