A Petty Officer ( PO ) is a rank in the rank group of non-commissioned officers in the naval forces of English-speaking countries, most notably the U.S. Navy.
In the British Royal Navy and other navies of the Commonwealth countries, the equivalent rank "Leading Rate".
United States Navy
The PO is usually a specialist or person responsible for a small group of team ranks.
In the U.S. Navy the rank is ever graded according to seniority and responsibility in three classes, with the " Petty Officer Third Class" ( PO3 ) is the lowest. Because of Petty Officer actually represents a rank group, it is most comparable to the Maaten the German Navy. The equivalent ranks of other U.S. armed services are Corporal, Sergeant and Staff Sergeant (USMC and USA) and Senior Airman, Staff Sergeant and Technical Sergeant (USAF).
Petty Officers are the one in charge and other technical specialists. Each PO has a rank ( rate) and a use designation ( rating ), similar to the MOS in other branches of the armed forces. Therefore, the full service name of a PO is composed of these two titles. A PO3, the use of term " Machinist 's Mate " is, is correctly called " Machinist 's Mate Third Class". The term PO is used only in general, eg to denote a group of PO or a PO whose use designation is unknown.
Any use designation has an official abbreviation, such as MM for Machinist 's Mate, Boatswain's Mate BM for or YN for Yeoman. If this shortcut is combined with the rank, an abbreviation for the particular PO is created, eg BM3 for Boatswain's Mate Third Class. Usually, a PO is then treated in correspondence and in printing name with this symbol. Often, the PO will be addressed only with its abbreviation without his last name, as is for example a PO3 (MM) Miller just called MM3.
The material versions of the ranks on the upper sleeves in the middle is the symbol for the use designation to find.
The commissioned officers of the U.S. Navy carry so-called service stripes on the left sleeve of their A-Class Uniform ( not in the daily service uniform ). Each of these red bar represents 4 years of service time. There is also a gold version, which is carried by non-commissioned officers that there are free from disciplinary action at least 12 years of service and.