Submarines do have the EPIRB. This submarine was also confirmed to be equipped with one. One of the reasons that this disappearance was weird was that there was

Submarines do have the EPIRB. This submarine was also confirmed to be equipped with one. One of the reasons that this disappearance was weird was that there wasn't even a trace of the EPIRB activating on this sub so we're not even sure if it "sank" https://arstechnica.com/information-technology/2017/11/us-navy-sends-underwater-robots-to-assist-in-search-for-argentine-sub/ https://arstechnica.com/information-technology/2017/11/us-na...