Station HYPO

Although the first class of On the Roof Gang (OTRG) convened on 1 October 1928, the story actually started in 1921, when the Office of Naval Intelligence (ONI) covertly acquired a photographic copy of the “Imperial Japanese Navy Secret Operating Code-1918.”  The code was in essence a dictionary containing a hundred thousand entries, and it took five years to translate.  There were only two Japanese linguists available, and there was no urgency or incentive to complete the project.  After all, having a code book is of no great advantage if one does not have access to messages being encoded in that code.