First lieutenant
From Halopedia, the Halo wiki
Template:Ratings Template:Rank Infobox First Lieutenant is a junior commissioned officer of the UNSC Marine Corps, Army, and Air Force, equal in rank to Lieutenant, Junior Grade in the UNSC Navy. Mostly they are given command of platoons, but oftentimes they can be given command of a company in the absence of a Captain such as in the case of First Lieutenant Melissa McKay in Halo: The Flood.
A Second Lieutenant usually receives a promotion to First Lieutenant after 18 to 24 months service.
In informal settings, First Lieutenants are referred to simply as "Lieutenant".
