@WaffleSekai
Good stuff translating this chapter! Just some corrections on the Military Terminology, since that doesn't translate well literally, plus some editorial suggestions (keep in mind, this is nagging on a high level, i'm thankful regardless);
Like Dagger said, "Siera" should be Sierra (Contacts are reported to the Captain by Sensor Station Identifier, like "Sierra" for Sonar, and a number)
"Emergency Teams" would be more commonly be referred to as "Damage Control Teams"
"Special Silent Dive" is best translated as "Silent Running"
If you want to get real fancy, you could translate stuff like "target has moved behind us" to "target is in our baffles", replace living quarters with "berthing" and use Naval terms like fore, aft, starboard, port.
I'm not sure if localizing TASS makes sense, since it's an official term, but if sailors talk about it in english, they usually call it a "towed array"
Page 20's "Motion Analysis" is usually called "TMA" or Target Motion Analysis in English, so a literal TL is pretty close
Page 25's Sikhval is most likely a reference to "Skhval", a russian supercavitating torpedo, because the gajikura's projectile seems to use a similar mechanism for underwater speed (Dagger also pointed this out)
"Guidance Cut" is fine, but in this use case the japanese may have been used synonymously with "Wire", since modern heavyweight torps are wire-guided, and so you could say "Wire Cut", because once torps go "active" they may move too fast to keep the wire intact
Page 41 Panel 2 is just a bit clumsy, i'd have written something like "Tokushima, you're already on it? Good job." "I noticed the knocking early this time." "Is this like retrieving a SBU diver?" "I guess it is."
They'd probably use "hatch" instead of "door" for the torp tubes, but both work
Page 42 has a bit of those same issues with context-removed MTL pronouns, which makes the TL really difficult to interpret
Page 43 Panel 1 would probably "No surface Anomalies" because it's likely the periscope officer reporting first, them the surfacing being ordered. Also, "like this" instead of "with this"
Again, thanks for sourcing the raws and doing the work, bud!