Chief Petty Officer 1st Class

Chief petty officer, 1st class, AKA CPO1, is the most senior non-commissioned member (NCM) rank of the Royal Canadian Navy. It is equivalent to a chief warrant officer (CWO) in the Canadian Army and Royal Canadian Air Force. It is immediately senior to the rank of chief petty officer 2nd-class and its equivalents, master warrant officer; it is part of the cadre of warrant officers.

The French language form of the rank is premier maître de 1re classe (pm 1).

The rank insignia of the CPO1 is the Coat of Arms of Canada, worn on both forearms of the Service Dress tunic and on slip-ons on both shoulders of other uniforms. Unlike other Chiefs and Petty Officers, CPO1s wear the cap insignia of Naval officers, although the brim of the peak cap remains plain, the same as other Naval NCMs.

CPO1s are generally initially addressed as "Chief Petty Officer Bloggins" or "Chief Bloggins", and thereafter as "Chief", although in correspondence the full rank or abbreviation is used before the member's name. The Coxswain of a Royal Canadian Navy ship will be answered as "Coxswain" (e.g. "yes Coxswain" or "no Coxswain") The full appellation "Chief Petty Officer 1st Class" in speech is generally used only when the "first class" distinction must be made, such as to distinguish between members with similar names but differing ranks, or on promotion parades. CPO1s are never addressed as "Sir" or "Ma'am", regardless of the protocol for their Army and Air Force equivalents; in Naval tradition, the titles "Sir" and "Ma'am" are reserved for officers.

One of the normal appointments of a CPO1 is that of coxswain, the senior NCM on a ship; it is roughly analogous to an Army Regimental Sergeant-Major (RSM). Due to the unified nature of the CF, however, it is not unheard-of for CPO1s — especially those of the "purple trades", such as logistics or military police to find themselves filling the appointment of RSM in what are otherwise considered "hard" army units (such as Service Battalions).

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