Common Military Units

Following is a list of Common Military Units found in the US (Yanks With Tanks) and UK military forces (Brits With Battleships; which, by extension, covers the rest of The Commonwealth). Other countries, e.g. Russia (who inherited its military from USSR) and China, use similar hierarchies with a few regional particularities, also outlined below. See also Common Ranks.

The Other Wiki has more information with tables.

Army units
The following section contains APP-6A codes for the listed units. APP-6A is a unified standard for map marking still widely used by NATO (despite being obsolete after APP-6B's publication). "APP" stands for "Allied Procedural Publication". Also, the abbreviation "CO" ("commanding officer") is used for the commander/leader of a unit for brevity's sake, regardless of whether said commander is an actual (commissioned) officer, a warrant officer, a NonCom, or even an enlisted rank. The size is the number of men and women serving in the unit.


 * Fire and maneuver team. The smallest army unit there can be consists of two foot soldiers who cover each other. This is particularly common for sniper teams who have to stay undetected and move fast across the battle zone. The Pripyat level in Modern Warfare is a pretty accurate depiction.
 * APP-6A symbol: Ø
 * Size: 2
 * CO: Fire and maneuver teams normally consist of servicemen with different rank, so the more senior one naturally takes command. This means that pretty much anyone from Private First Class (OR-2) to Colonel (OF-5) can command an F&MT.


 * Fireteam. The more common smallest army unit is a normal fireteam, slightly larger than a F&MT. A fireteam provides the maximum tactical flexibility possible with the minimal size. It usually consists of a team leader, a rifleman (both equipped with assault rifles, sometimes with a grenade launcher), a grenadier (assault rifle, always with a grenade launcher, and trained and heavily practiced in its use), and a machinegunner (lays suppressing fire with an M249 or other such light machine gun). Depending on the assignment and what they may be expected to encounter or do, the basic rifleman is sometimes replaced with an anti-tank specialist, medic, designated marksman or some other kind of specialist soldier. Note that the US Marines have a slightly different idea of a fireteam: the rifleman acts as a scout, the team leader doubles as grenadier, the machinegunner is the Number Two, and the fourth marine is a secondary machinegunner who carries extra ammo.
 * Symbol: Ø (yes, fire and maneuver teams are lumped with normal fireteams)
 * Size: 4–5
 * CO: Lance corporal (OR-3) to sergeant (OR-5/6)


 * Squad. Consists of two or more fireteams and a coordinating commander. In Commonwealth armies, the term section is used instead, while fulfilling mostly the same functions. In the US, "section" is used only for cavalry, air defense and field artillery. Sometimes, the term patrol is also used because the squad is the smallest unit sent to patrol a certain area.
 * Symbol: • (squad), •• (section)
 * Size: 8–16 (squad), 8–12 (section)
 * CO: Corporal (OR-4) to Staff Sergeant (OR-6/7)


 * Platoon. Consists of two or more squads, sections, or vehicles. A platoon is the smallest unit normally led by a commissioned officer (a lieutenant), who is known as "platoon commander". He is usually assisted by a senior NonCom (OR-6 to OR-7) as his "platoon sergeant".
 * Symbol: •••
 * Size: 25–60
 * CO: Warrant Officer (WO-1) to First/Second Lieutenant (OF-1)


 * Company. Consists of two to eight infantry platoons and has the same size as an artillery battery, a U.S. Cavalry troop, or Commonwealth armor or combat engineering squadron.
 * Symbol: I
 * Size: 70–250
 * CO: Chief Warrant Officer (WO-2 to WO-5), Captain (OF-2), or Major (OF-3)


 * Battalion. Consists of two to six infantry companies or artillery batteries. A U.S. Cavalry squadron consists of 2-6 troops, and a Commonwealth armored regiment, of 2-6 squadrons. A battalion is the smallest unit that can be commanded only by commissioned officers (Lt.Col.).
 * Symbol: II
 * Size: 300–1000
 * CO: Lieutenant Colonel (OF-4)


 * Regiment or group. Consists of two or more battalions.
 * Symbol: III
 * Size: 2000–3000
 * CO: Colonel (OF-5)


 * Brigade. Consists of two or more regiments, or three to six battalions/Commonwealth regiments. Some confusion may arise with the US, where the brigade and the regiment are currently considered roughly equivalent.
 * Symbol: X
 * Size: 2000–5000
 * CO: Colonel (OF-5) to Brigadier/Brigadier General (OF-6)


 * Division. Consists of two to four brigades or regiments. The standard counting level for comparing military forces, especially in the Second World War and Cold War.
 * Symbol: XX
 * Size: 10,000–20,000
 * CO: Major General (OF-7)


 * Corps. Consists of two or more divisions.
 * Symbol: XXX
 * Size: 30,000–80,000
 * CO: Lieutenant General (OF-8)


 * Army. Consists of two to four corps.
 * Symbol: XXXX
 * Size: 60,000–100,000+
 * CO: General (OF-9)


 * Army group. Consists of two or more armies.
 * Symbol: XXXXX
 * Size: 250,000+
 * CO: General (OF-9) to Field Marshal (OF-10)


 * Region, theater, or front. Consists of four or more army groups. In the Soviet Union, the name "Front" was commonly used for an army group, while several army groups were a Strategic Direction.
 * Symbol: XXXXXX
 * Size: 1,000,000+
 * CO: General (OF-9) to Field Marshal (OF-10)

Navy units
Because any unit smaller than a vessel wouldn't make sense in the navy, navy sizes are given in ships rather than personnel. Each ship is normally commanded by a commissioned navy officer, and although there are no ironclad rules, The Captain's rank generally corresponds to the size of his vessel: e.g. an Ensign would command a gunboat, whereas a capital ship can only be commanded by a navy captain.

Modern navies have a very flexible organization compared to ground forces because vessels are often shuffled across the seas as the current strategic situation demands (as opposed to rather rigid and stable structures in the army). This particular section describes primarily the US Navy organization.


 * Task Element. The smallest navy unit, consisting of exactly one large vessel, regardless of her size. In practice, a carrier would not travel without escorts.
 * Size: 1
 * CO: Commander (OF-4) to Captain (OF-5)


 * Task Unit. Consists of a small number of vessels (task elements). A further distinction is made for Flotilla (not capital ships, usually of the same or similar types) and Squadron (includes capital ships; not to be confused with ground and air squadrons).
 * Size: 3–4
 * CO: Rear Admiral (lower half)/Commodore (OF-6)


 * Task Group. Consists of two or more task units, usually combining many types of vessels that complement each other.
 * CO: Rear Admiral (OF-7)


 * Task Force or Battle Fleet. Consists of two or more task groups, uniting a large number of ships of all types.
 * CO: Vice Admiral (OF-8)


 * Fleet. Consists of all vessels in an ocean or general region, either those allocated to that area or which just happen to be there. For example, the US Sixth Fleet consists of all the vessels currently in the Mediterranean Sea (regardless of homeport), while the Russian Northern Fleet consists of all the vessels allocated to the Atlantic Ocean (even if a ship based in the Black Sea winds up in the Atlantic, it is still not part of the Northern Fleet).
 * CO: Admiral (OF-9)


 * Navy or Admiralty. The nation's entire naval forces.
 * CO: Fleet Admiral/Admiral of the Fleet (OF-10)

Additionally, a chain of command is maintained onboard each vessel, depending on its size and purpose. This is where the navy NonCom and lower ranks come into play. Generally the ship is divided up into functional units:


 * Workcenter. A group of sailors that concentrate on one specific operation or piece of equipment that they maintain and practice with. Within an Auxiliaries division, there may be workcenters that deal with Air Conditioning, Water Distilling, Steering Gear, etc. Depends entirely on the equipment installed and the role of the ship.
 * CO: Experienced sailor (usually around E-5) to Senior Enlisted (E-7).


 * Division. A group of sailors (probably not more than 30 or so, and usually around 10-20) devoted to one specific aspect of the ship's operations, with an officer or senior enlisted for leadership. For example, within an Engineering department there may be divisions devoted to Main Propulsion, Electrical, Auxiliaries, or Repair.
 * CO: Again depends on size, but usually led by a Junior Officer from Ensign (OF-0) to Lieutenant (OF-2), with a senior enlisted (E-7 to E-9) for backup and mentorship. Called a Division Officer.


 * Department. A portion of the ship's officers and crew devoted to a particular broad aspect of the ship's operations, such as Engineering, Combat Systems, Operations, Weapons, Supply, etc as per the ship's role.
 * CO: Depending on size, from a Lieutenant (OF-2) all the way to a Captain (OF-5) on very large ships. Called a Department Head.


 * Ship. The vessel itself. May actually be a submarine or an aircraft squadron, which are broken up similarly, though squadrons will typically have many more Junior Officers than divisions for them to lead as most navies only allow officers to be pilots.
 * CO: Depends on size, ranges from Lietenant Commander (OF-3) to Captain (OF-5). The Captain is always "The Captain" aboard his/her own ship, regardless of actual rank. If other officers are aboard who hold a rank actually called Captain, they may be "courtesy promoted" to the next-higher rank ("Commodore" for another naval officer, "Major" for anyone else) to avoid confusion. Likewise, the officer-in-charge of a vessel can be referred to as "the skipper" if further clarification is necessary.

Special note for aircraft carriers: the complement of aircraft and accompanying personnel on a carrier are called its air wing, it has it's own commanding officer (immediately subordinate to the ship's CO) and it's internally structured much like a wing in the air force section below, just with naval ranks. The main difference is that it encompasses a ship rather than an aircraft type or mission: while the air force might have elements of multiple wings at a given airbase, a ship has all her aircraft under one command.

Air force units
The air forces hierarchy varies the most across different countries compared to other service arms. The general tendency, however, is for air force units to be much smaller than their ground and navy counterparts because of the much higher qualification requirements. To put it bluntly: a tank or a gunboat won't go down because of a single loose screw, but a fighter jet may very well do.

The size below is given in personnel (P) and aircraft (A) assigned to a unit. APP-6A symbols are given solely for comparison with respective army units.


 * Section or Detail. The smallest air force unit, consisting of two to three planes, i.e. the leader and his Wing Man. Their responsibilities are similar to the infantry fire and maneuver team.
 * Symbol: ••
 * Size (P): 2–4
 * Size (A): 2–3
 * CO: Junior Officer (OF-1 to OF-2) or Senior NonCom (OR-7 to OR-9)


 * Flight. Consists of two sections plus maintenance and support crew (this is where the air force NonCom and lower ranks come into play).
 * Symbol: •••
 * Size (P): 20–100
 * Size (A): 4–6
 * CO: Captain/Flight Lieutenant (OF-2) to Major/Squadron Leader (OF-3)


 * Squadron. Consists of three to four flights.
 * Symbol: II
 * Size (P): 100–300
 * Size (A): 7–16
 * CO: 	Major/Squadron Leader (OF-3) to Lieutenant Colonel/Wing Commander (OF-4)


 * Group. Consists of three to ten squadrons. The Royal Air Force groups squadrons into wings, and wings, into groups (whereas USAF does it the other way around), and the RAF wings are smaller (3-4 squadrons) than USAF groups. A wing/group attached to particular air base or aerodrome is called station in RAF.
 * Symbol: III
 * Size (P): 300–1,000
 * Size (A): 17–48
 * CO: 	Lieutenant Colonel/Wing Commander (OF-4) to Colonel/Group Captain (OF-5)


 * Wing. Consists of two or more groups. See also the note on RAF wings and groups above.
 * Symbol: X
 * Size (P): 1,000–5,000
 * Size (A): 48–100
 * CO: 	Brigadier General/Air Commodore (OF-6) to Air Vice-Marshal (OF-7)


 * Numbered Air Force. Unique to USAF, a NAF consists of two or more wings. Its exact size varies depending on the region.
 * Symbol: XX
 * CO: Major General (OF-7)


 * (Major) Command or Tactical Air Force. All aircraft and personnel deployed in a region, whose numbers vary greatly.
 * Symbol: XXXXX
 * CO: Air Marshal (OF-8) to General/Air Chief Marshal (OF-9)


 * Air Force. The nation's entire air forces.
 * Symbol: XXXXXX +
 * CO: General/Air Chief Marshal (OF-9) to Marshal of the Royal Air Force (OF-10)

By nation
The following section contains some international equivalents of the units outlined above. Original spelling is given, with the rough pronunciation in brackets for Cyrillic Alphabet. A few more notes:


 * Bundeswehr has a ground unit larger than a platoon but smaller than a company called "Staffel". Its APP-6A symbol is four dots (••••). It is not to be confused with the Luftwaffe Staffel (see below), which is an equivalent of USAF squadron.
 * An artillery battery (equivalent of an infantry company) is called "батарея" (batareya) in Russian.
 * The Strategic Rocket Forces also have the artillery battalion renamed to "дивизион" (divizion), which shouldn't be confused with the much larger division ("дивизия").

Air force units
The formations larger than that wing/group are usually lumped together with the army ones.

Infantry
Your basic everyday soldier. Will carry an assault rifle with a few machine guns around to provide support. Will have to walk or get a truck to their destination and generally do all the hard work.

Mechanized Infantry
Similar to regular Infantry, but is somewhat more mobile and has more firepower due to the support of an APC or IFV. However, these are generally smaller that infantry squads because you can only fit so many men into an armoured vehicle.

Cavalry
Soldiers who ride horses, hence, inherently cool. Now largely relegated to ceremonial roles or an old name retained for a unit that does something else (e.g. the Household Cavalry, who are a reconnaissance regiment). In skilled hands, The Cavalry was known to turn the tide of battle, hence, it is a Trope Namer.
 * In some military forces (such as the United States Army), more modern units, such as Reconnaissance, Armor, and Aviation, might be described as "Cavalry", including Infantry troops that ride vehicles or aircraft into battle (interestingly enough, a soldier who rides in a helicopter can be a Cavalry Trooper, but this isn't the case for a Paratrooper, even though they both fight primarily on the ground. This is due to varying traditions behind the two groups of soldiers.)

Armored
Tank Goodness, basically.

Army Aviation
Usually helicopters. Sometimes light attack aircraft too.

Paratroops/Airborne
It's Raining Men. Troops designed to be deployed by aircraft, either gliders or parachutes. During the Cold War, the USSR maintained no less than eight divisions of airborne troops (one training, seven regular) and their airborne forces, the VDV, were separate from the other arms of service.
 * In point of fact these have been eclipsed since World War 2 as the helicopter does more or less the same chore with fewer of the disadvantages such as scatter(less of a problem with modern parachutes), the difficulty getting heavy equipment in, the requirement of total loss of contact with base and lack of means of retreat, and just the need to train people to jump. Today jumping is mostly a special forces insertion technique and big jumps are rare.

Engineers
Very often omitted in fiction in favor of Easy Logistics.

Air Defense
Anti-Air, also nerfed in fiction-- see Point Defenseless.

Logistics/Supply
In Real Life, probably the single most important part of a military operation. In fiction... never mind.

Signals
Responsible for communications.

Medical
The Medic.

Artillery
Often unseen, but specialise in a unique form of Death From Above thanks to their use of real life BFG's and the closest thing one would get to a Wave Motion Gun.

Special Forces
Conservation of Ninjutsu personifed, and often get first pick of the latest toys.

Military Police
To make sure that the soldiers don't do anything illegal. Often found at the local nightspots dragging people to the stockade or brig. In Real Life, may also be tasked with defending rear-area supply lines, managing POWs (Abu Ghraib is what happens when this goes wrong), and/or acting as meat shields for the command staff.
 * More dramatically these are useful counterinsurgency units as partisans often use tactics similar to those of criminals and hence need a response from units who fit the borderline between constabulary and military roles.

Guards
Made obsolete by changing security techniques, Guards troops are the ones that guard the person of a monarch. In modern times bodyguarding has become more sophisticated then just putting lots of walking sacks of meat between the assassin and the target and Guards units are often as much parade units or honor designations(in the Red Army, weirdly, distinguished units were called guards even though they did no guarding except of their own billet for the name was equiv to a Presidential Unit Citation in America). The most important part of security work is often done by plain clothes agents or special forces or the more specially trained police. But Guards units do carry real weapons, and despite the gaudy clothes they wear for tourists, do also provide an extra assist.

Irregulars
This is a generic for guerillas or local auxiliaries. Many nations have found a way to officialize them, sometimes by finding a specialized officer who can make use of them. While requiring painstaking diplomacy they possess local knowledge and in some cases are easier to downsize in peacetime. Sometimes irregulars associated with a given army for to long will tempt overtidy bureaucrats into making it something indistinguishable from the rest of the service except for having a cool designation. This is a wasteful practice, because the whole point of them is often that their ancestors had lived a civilian life that gave them qualities hard to copy in just any soldier, however frustrating irregulars can be. Special forces are in many ways the modern incarnation though if there was a general war, again the practice of recruiting local will arise again(indeed it seems to have in many places where the US is committed). The difference is that Special forces are from the same manpower pool as regulars, while irregulars tend to be from client polities or even straight out mercenaries.

Capital Ships
These are ships assigned to the main fleet. They are the biggest and the baddest for they are expected to take a lot of damage and go on fighting. Often they are impractical for any other use and thus will never be found alone. In the Hellenistic Age ships above the Trieme class were capital ships while triemes(which were once the capital ships themselves)were small craft. The excellent Rhodian navy also maintained a modified trieme, the Triheimiola as a police vessel. In the Wooden Ships and Iron Men days ships of the line were the capital ships. In World War 2 there was some ambiguity as aircraft carriers were the main capital ship at least in the Pacific, but because they launched aircraft so far could do some of the roles of smaller ships. Cruisers, conceived as replacements for the frigate of earlier times were often mustered as capital ships in late 1942 and early 1943 for night surface actions. The battleships were capable of the job but were to big of gas guzzlers and in any case admirals feared to lose them.

Screener, Escort, or Pursuit ships
This is the other part of the two basic forms of naval vessel there have been through history(naval scholar Julian Corbett divided them into three but the third seems to be smaller versions of screeners for close inshore work). These scout ahead of the fleet, convoy merchants, raid commerce, and in general do most of the work. Basically only a fleet can dominate a given territory and only screeners can dominate places where the fleet is not which is most of the ocean. In Wooden Ships and Iron Men days these were frigates. In World War 2 they were destroyers. Commerce raiding was usually done by submarines and in some ways the classic contenders were several destroyers playing hide and seek with a sub.