Ka kammala wannan magana: A shekara ta 1943, Munk da Sverdrup sun soma neman hanyar da za su iya sanin tsayin raƙuman ruwan teku. Allies sun shirya don
sauka a Arewacin Afirka, inda kwana biyu cikin uku raƙuman ruwa suke sama da ƙafa shida. An dakatar da saukowar rairayin bakin teku a cikin Carolinas lokacin da raƙuman ruwa suka kai wannan tsawo saboda suna da haɗari ga mutane da kuma jirgin ruwa. Munk da Sverdrup sun sami ka'idar da ke tattare da tsayin raƙuman ruwa da kuma tsawon lokaci zuwa saurin da tsawon iska da kuma nisan da yake busawa. Allies sun yi amfani da wannan hanyar a fagen yaƙi na Pacific da mamayewar Normandy a ranar D.