At 3:50 P.M. on the afternoon of 17 December 1927, the commandant of the Boston Navy Yard received a flash radio message from the U.S. Coast Guard Destroyer Paulding: "Rammed and sank unknown submarine off Wood End, Provincetown." Within minutes, the worst fears of many were realized when it was confirmed that the submarine was the USS S-4. Though rescue efforts immediately began in earnest, it was too late for the 39 crewmen and a civilian observer aboard S-4. Most had already perished; six men trapped in the torpedo compartment would not be rescued in time.
While the events that transpired after the sinking are well known — the rescue efforts, the recovery operations, the trial of those involved in the court of public opinion, and the spectacle of several public investigations — what is less so are the findings of those inquiries.
How is it that a Coast Guard Destroyer could ram and sink and Navy submarine? As with most disasters, the causers were a number of small factors that alone amounted to little, but in combination with one another led to tragedy.