[1] Petty Officer Third Class Affiliation UNSC Navy Higher Rank Petty Officer Second Class Lower Rank Crewman Known Petty Officer Third Classs John-117 (2525) Cho Sam Marcus (Tech Officer Third Class) Pauley R. Coney Holly-G003
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Petty Officer Third Class is the fourth enlisted rank (E-4) of the UNSC Navy and is the lowest rank of non-commissioned officer, or NCO. Directly above it is Petty Officer Second Class and directly below is Crewman. It is equal to the rank of Corporal in the UNSC Marine Corps, Corporal and Specialist in the UNSC Army, and Senior Airman in the UNSC Air Force.

In informal settings, a Petty Officer Third Class is typically called a "Petty Officer".

In the UNSC Navy, enlisted personnel are referred to by their rating and rate (rank).

SourcesEdit

1. ↑ This is the insignia for a US Navy Petty Officer Third Class. However, in Halo 3 the insignia for Master Chief Petty Officer is shown to be the same as for the US (with the standard "crow" changed for that of the UNSC "crow"). It is inferred that this applies to all UNSC Navy Enlisted rank insignes.

UNSC Defense Force enlisted ranks
	E-1	E-2	E-3	E-4	E-5	E-6	E-7	E-8	E-9	Senior Enlisted Advisor
Air Force:	AB	Amn	A1C	SrA	SSgt	TSgt	MSgt	SMSgt	CMSgt - CCM	CMSAF
Army:	PV1	PV2	PFC	SPC - CPL	SGT	SSG	SFC	MSG - 1SG	SGM - CSM	SMA
Marine Corps:	Pvt	PFC	LCpl	Cpl	Sgt	SSgt	GySgt	MSgt - 1stSgt	MGySgt - SgtMaj	SgtMajMC
Navy:	CR	CA	CN	PO3	PO2	PO1	CPO	SCPO	MCPO - CMDCM - FORCM - FLTCM	MCPON