Veteran submariner on how sonar crews tirelessly hunt enemies they can't see

Re:Veteran submariner on how sonar crews tirelessly hunt ene... by Anechoic on Wednesday August 12, 2020 @03:37PM (#24135888)

Keep in mind that's likely not related to the dB sound pressure level in air that we're all familiar with. dB is a logarithmic ratio to pressure to a reference. In air, that reference is 20µPa, acoustic pressure in water typically uses a different reference (1µPa). There is also an adjustment of 36 dB to account for the higher impedance of water. So 235 dB in water is roughly 173 dB SPL -- still loud, but many orders of magnitude lower.

[0] https://fas.org/man/dod-101/sys/ship/acoustics.htm

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Re:Veteran submariner on how sonar crews tirelessly hunt ene... by GCPGCP on Wednesday August 12, 2020 @11:38PM (#24139734)

This is what you can expect https://www.youtube.com/watch?v=sCmyZYYR7_s&t=90s

This diver was near a sub base for training.

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Re:Veteran submariner on how sonar crews tirelessly hunt ene... by MrBuddyCasino on Thursday August 13, 2020 @09:34AM (#24143159)

Comments say this was very likely not a sub‘s sonar.

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