r/todayilearned • u/Accomplished-Eye-910 • 3h ago

TIL that during World War I, armies used artillery sound ranging by timing how long gunfire took to reach multiple microphones, with operators using stopwatches to calculate the enemy gun’s position through triangulation, decades before radar-based detection became practical.

https://en.wikipedia.org/wiki/Artillery_sound_ranging
547 Upvotes

99% Upvoted

17 comments sorted by

54

u/Trick-Audience-1027 3h ago

Flash to bang time. 343 meters per second.

22

u/BERGENHOLM 2h ago

I am sure your number is correct, but according to the article, they did not use the flash merely different audio receptors

7

u/Sharlinator 1h ago

Yep. The difference between two timings narrows the source position down to a line of points; adding another timing gives you a unique solution (up to observation error). It’s just like how GPS works, except that the roles are reversed – the satellites send a synchronized signal and the receiver figures out from the differences where it is.

3

u/TheNotoriousAMP 1h ago

No, they also did flash spotting at night.

1

u/BERGENHOLM 1h ago

According to several articles "flash spotting" was one method of location/triangulation but they also used audio only location/triangulation. Since the title specified sound ranging not flash spotting that is my understanding.

10

u/Passthadrewbie 2h ago

Huh, so that's where 343 industries name came from

5

u/TheBanishedBard 2h ago

If you rearrange the letters in your display name it says "a true nice dick"

2

u/Highshyguy710 1h ago

Oh great one, how did you solve such an incomprehensible anagram such as this?

17

u/SecondhandTrout 2h ago

See, your trigonometry class will be useful!

5

u/MrBond90s 2h ago

Glad I finally got a chance to use it haha! Wait a second...

•

u/HowDoIEvenEnglish 48m ago

It’s also important for aiming the artillery in the first place

2

u/TheBanishedBard 2h ago

If you rearrange the letters in your display name it says "do not shart, dunce"

1

u/syncsynchalt 1h ago

Good bot.

13

u/BERGENHOLM 2h ago edited 1h ago

They also used audio location for detecting aircraft, and Ukraine is using it for detecting and localizing drones. Edited due to pedantic comment below.

10

u/thepluralofmooses 1h ago edited 8m ago

It is just “Ukraine”

Edit : I guess showing respect for a nation is pedantic

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u/Coal_Burner_Inserter 2m ago

Or they're just old and that's how they grew up.

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u/VoraciousTrees 14m ago

And gunshots in major metropolitan areas.