▁a ▁naval ▁action ▁fought ▁somewhere ▁in ▁the ▁Atlantic ▁Ocean ▁during ▁World ▁War ▁I . ▁An ▁un ident ified ▁Kaiser liche ▁Marine ▁U - bo at ▁attacked ▁three ▁armed ▁trans ports ▁of ▁the ▁United ▁States ▁Army ▁and ▁Navy , ▁but ▁failed ▁to ▁damage ▁the ▁American ▁ships ▁before ▁she ▁was ▁s unk . ▁ ▁Action ▁On ▁ 4 ▁April ▁ 1 9 1 8 , ▁the ▁armed ▁trans ports ▁, ▁ ▁and ▁ ▁were ▁ste aming ▁back ▁to ▁the ▁United ▁States ▁in ▁con voy ▁after ▁having ▁completed ▁a ▁tro op ▁transport ation ▁voyage ▁to ▁France . ▁At ▁ 1 1 : 4 5 ▁in ▁the ▁morning , ▁a ▁German ▁U - bo at ▁of ▁unknown ▁design ation ▁sur fac ed ▁and ▁fired ▁tor ped o es ▁at ▁Mall ory . ▁Look outs ▁ab o ard ▁the ▁transport ▁sp otted ▁the ▁tor ped o es , ▁allowing ▁the ▁ship ▁to ▁successfully ▁e va de ▁them . ▁ ▁The ▁sub marine ▁was ▁sight ed ▁by ▁the ▁other ▁American ▁trans ports ; ▁all ▁three ▁ships ▁opened ▁fire ▁with ▁their ▁main ▁guns , ▁and ▁appeared ▁to ▁hit ▁the ▁U - bo at ▁as ▁she ▁sub mer ged . ▁The ▁vessels ▁then ▁man eu ver ed ▁in ▁close ▁and ▁depth ▁charged ▁the ▁last - known ▁location ▁of ▁the ▁Germ ans . ▁The ▁three ▁American ▁vessels ▁were ▁cred ited ▁with ▁s inking ▁the ▁attack ing ▁sub marine . ▁The ▁con voy ▁reached ▁the ▁United ▁States ▁on ▁or ▁about ▁ 1 3 ▁April ▁ 1 9 1 8 . ▁ ▁See ▁also