A lokacin yakin duniya na biyu Nazi Jamus ta submarine rundunar jiragen ruwa na U-boats kusan starved Birtaniya cikin biyayya da kuma inflicted babbar asarar a kan Amurka coastal shipping. Nasarar submarines ya kai ga ci gaban da sabon anti-submarine convoy escorts a lokacin na farko da na biyu yakin duniya, kamar jirgin ruwa mai hallaka. confusingly, da yawa daga cikin wadannan sabon iri soma sunayen da karami warships daga shekaru na jirgin ruwa, kamar corvette, sloop da frigate. Tambaya: A lokacin da ya karshe ya tabbatar da submarines su m?
karshen yakin duniya na farko