Fireteam

A fireteam is the smallest infantry unit in the UNSC Army, UNSC Marine Corps and Spartan-IV Regiment. Fireteams are typically led by junior non-commissioned officers and do not contain any officers. A fireteam is roughly the equivalent to the Covenant Army's file. A squad is immediately superior to a fireteam in the UNSC Army and Marine Corps, while a section is immediately superior to a fireteam in the Spartan-IV Regiment.

More information at halopedia and wikipedia.

Background
Fireteams are typically made up of three to five soldiers and commanded by a junior NCO. Fireteams are used for tactical flexablility in both the UNSC and the SIV Regiment. A fireteams' organisation will sometimes vary depending on its role, and is usually organised quite differently between the UNSC Army, the UNSC Marine Corps and the SIV Regiment.

UNSC Army
Typically a UNSC Army fireteam will contain a team leader, a rifleman, an automatic rifleman and a grenadier. The team leader will usually be a corporal or a sergeant and wield an MA37 ICWS or an M392 DMR. The other members of the team are usually privates and privates first class. Usually, the rifleman wields an MA37 ICWS or an M392 DMR, the automatic rifleman wields an M247 GPMG and the grenadier wields an MA37 with an attached M301 grenade launcher. Sometimes (although uncommon), the grenadier will wield an M319 IGL. There are two fireteams per squad. Usually, if there is more than four fireteam members, there will be extra riflemen.

UNSC Marine Corps
The UNSC Marine Corps follows a similar organisation scheme to the Army. A Marine Corps fireteam contains a team leader (corporal, sometimes lance corporal) who wields an MA5B ICWSwith an attached M301, a rifleman (private or private first class) who also wields an MA5B or a BR55, an automatic rifleman (private or private first class) who carries an M247, and an assistant automatic rifleman (private or private first class) who also carries an M247, as well as extra ammunition. In a five-man fireteam, it is normal to have two riflemen.

Spartan-IV Regiment
In the Spartan-IV Regiment, fireteams are organised quite differently from UNSC fireteams. Although the Spartan-IV regiment seems to be roughly based on typical Commonwealth organisation, fireteams do not match that organisation. Fireteams contain three members each in the SIV Regiment. Since the SIV Regiment recruits from all four branches of the UNSC, there are numerous different ranks that a soldier may have for a position.

Fireteams work like this, there is a commander who is also either the commander of their section or the second in command of their section. Charlie fireteams contain the commander of the section, while Delta fireteams contain the second in commands. Sections contain a sniper, a grenadier, a technician, a pilot, a medic and a vehicle specialist. Fireteams may contain any three of these positions, as long as the other team in their sections contains the remaining three. Typically, fireteams will contain a sniper or technician, a pilot or medic and a grenadier or vehicle specialist. Each member is usaully trained in two aspects (most pilots are also given medical training and vice versa, so that the fireteams can function properly).

In a fireteam, there is always a commander and three other men. The commander usually holds the rank of airman first class or senior airman (Air Force), private first class or corporal (Army), lance corporal or corporal (Marine Corps), or crewman or petty officer third class (Navy). The ranks are listed in respective order of section second in command or section commander. The other three men will hold the ranks of airman basic or airman (Air Force), private (Army), private or private (Marine Corps), or crewman recruit or crewman apprentice (Navy).

Notable Fireteams

 * Fireteam November (C?/?/A)
 * Fireteam Gestalt (C?/?/A)
 * Fireteam Foxtrot (C3/8/C)
 * Fireteam Zeppelin (D3/8/C)

Trivia

 * In the Spartan-IV Regiment, members get to name their fireteams. This idea orginated from various changes in the series that resulted in there being a Fireteam Foxtrot and a Fireteam November despite the organisational structure naming fireteams as either Charlie or Delta.