[1] Petty Officer First Class Affiliation UNSC Navy Higher Rank Chief Petty Officer Lower Rank Petty Officer Second Class Known Petty Officer First Classs Frederic-104 Healy Jai-006
	[Source]

Petty Officer First Class is the sixth enlisted rank of the UNSC Navy and is a non-commissioned officer. It is equal in rank to Staff Sergeant in the UNSC Marine Corps and UNSC Army, and Technical Sergeant in the UNSC Air Force. It is directly above Petty Officer Second Class and below Chief Petty Officer.

In informal settings, Petty Officers First Class are typically called "Petty Officer".

SourcesEdit

1. ↑ This is the insignia for a U.S. Naval Petty Officer First Class in the Boatswain's Mate rating. However, in Halo 3 the insignia for Master Chief Petty Officer is shown to be the same as for the U.S. 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