While I agree, it's impossible for us to tell who might be responsible, I wouldn't dismiss foreign subs as easily detected. AIP diesel-electrics are the quietes

While I agree, it's impossible for us to tell who might be responsible, I wouldn't dismiss foreign subs as easily detected. AIP diesel-electrics are the quietest things out there, and Sweden has one of the best. https://www.thedrive.com/the-war-zone/21662/swedens-notorious-little-carrier-killing-sub-just-got-some-major-upgrades https://www.thedrive.com/the-war-zone/21662/swedens-notoriou...