Inner Sphere military structure
Every military unit in the BattleTech universe, whether regular or mercenary, is divided into sub-units to facilitate organization, deployment, and combat operations. Mercenary units are extremely varied; some, like Carlyle's Commandos were a single lance while others, like Eridani Light Horse, Wolf's Dragoons, and the 12th Star Guards, consist of several regiments.
There is some common terminology for these organizational structure, but there are differences between BattleMech, infantry, and Aerospace Fighter units. There are also disparities between the five great houses and especially between entities in the Periphery. Clan military structure and that of ComStar and the Word of Blake's military forces are substantially different than any Inner Sphere unit organizations.
 Unit Organization
Each unit is organized differently in practice, but many follow a basic organizational structure that enables them to integrate with other units easily and effectively.
The lance is the smallest organizational unit, equivalent to an infantry platoon. A 'Mech lance consists of four separate BattleMechs (although occasionally a "light lance" consists of only three 'Mechs) and are categorized based upon the average weight of the 'Mechs that comprise it (Light, Medium, Heavy, Assault). A lance commander is usually either a non-commissioned officer (NCO) or a low grade officer (lieutenant or equivalent). Lance commanders are directly engaged in combat operations and are responsible for the 'Mechs under their command.
A Standard Lance consists of one light, one medium, and two heavy BattleMechs.
In addition to four 'Mech pilots, there are normally four to six additional support personnel, making a lance roughly ten individuals. Three lances comprise a company.
 Augmented Lance
After learning of the Novas used by the Clans, the CCAF began to experiment with mixing unit types. Their first successful experiment created an Augmented Mech Lance that combined four BattleMechs with two combat vehicles. This became the "standard" augmented 'Mech lance. A "secondary" augmented 'Mech lance was created by combining four BattleMechs with two squads of battle armored infantry. The CCAF then turned their attention to Armor lances. The "standard" augmented armor lance combines four combat vehicles with two BattleMechs; The "secondary" augmented armor lance combines four combat vehicles with four suits of battle armor-equipped infantry.
 Air Lance
A company consists of three lances and normally some ancillary units, usually scout, armor, or artillery. A company commander is normally either a major or captain (or equivalent). The company commander is usually the leader of the command lance of a company and is directly involved in combat operations. Companies are more self-sufficient than lances and consist of the combat troops and support personnel, including medical, technician, and planetary transport vehicles (DropShips). Companies may also provide reconnaissance and artillery support lances under its command.
In addition to twelve 'Mech pilots and the eighteen support personnel, there are usually additional support or specialist personnel, making a company roughly sixty individuals. Three companies comprise a battalion. Mercenary units commonly do not exceed the size of a company.
 Augmented Company
This formation is used only by the CCAF. It has the twelve combat units of a typical company, but these are organized into two Augmented Lances of any type.
A battalion consists of three companies and is a large organization. It is normally composed of at least thirty-six 'Mechs plus aerospace, artillery, reconnaissance, medical, and numerous other support staff and personnel. Overall, a battalion may consist of over two or three hundred individuals. Battalions are commanded by either a lieutenant colonel (or equivalent). Battalion commanders normally do not participate directly in combat operations, but personal preference dictates this. Most battalion commanders direct operations rather than engage enemy forces.
Battalions are extremely self-sufficient and capable fighting forces. They are capable of traveling over the surface of a planet and deploying significant fire power anywhere within a short period of time. Many mercenary units never achieve a size comparable to that of a battalion.
 Square Battalion
A variant battalion consisting of four companies, and may also have a Command Lance (48 BattleMechs/aerospace fighters). This organizational structure came about when the Inner Sphere militaries re-purposed the air lance that would support each company.
Regiments are very large organizations and the great houses normally organize their regular units into regiments; these are the largest formations in common use. This is traditionally the lowest level of organization that a house's high command will direct (outside of mercenary units). Regiments are commanded by colonels or their equivalent. Regimental commanders rarely engage in combat operations personally; the ability to organize a regimental-sized group is usually not possible on the field of battle. The size of the unit in personnel is not just based upon the combat forces, but it also includes the technical, transportation, scout, and other support personnel and materiel. Regiments are self-sufficient units and usually have their own dedicated DropShips and possibly even JumpShip.
Regiments consist of three to five battalions, commanded by a Colonel or General, for a total of one hundred and eight to one hundred and eighty 'Mechs or combat vehicles. Additional support battalions such as infantry are often attached to the regiment as well.
 Augmented Regiment
In 3081 the Capellan Confederation began organizing Augmented Regiments that expanded the use of their Augmented Lance and Augmented Company organization. Each regiment of the CCAF was reorganized to include a battalion that consisted of four companies of two Augmented Lances and a command lance. Each augmented lance in this battalion consisted of four 'Mechs and a pair of conventional tanks. The four companies provide thirty-two 'Mechs and the command lance adds four more. This gives the Augmented regiment the same firepower as a standard battalion, but includes sixteen armored vehicles for additional fire support. The other battalions form temporary augmented formations by adding battle armor squads to existing 'Mech lances.
 Regimental Combat Team
First developed by the Star League Defense Force, a Regimental Combat Team was originally composed of four combat regiments and a support and transport element. The most experienced regimental commander was put in charge of the RCT, and the four combat elements trained together to improve unit cohesion. These RCTs tended to be permanently assigned to a location in order to better understand and exploit the local terrain. A surviving example of the SLDF's RCT concept is the Eridani Light Horse.
The Federated Suns would develop their own Regimental Combat Teams thanks to First Prince Melissa Davion after she came to power in 2876. The AFFS' version of an RCT is a large multi-regiment formation that consists of a regiment of BattleMechs, three regiments of combat vehicles, five regiments of infantry, two AeroSpace Fighter wings, and a battalion of artillery. Unlike the task forces that had been used previously, these regiments are permanently assigned to work together. These RCTs are usually named for the BattleMech regiment.
 Light Combat Team
After the widespread destruction of the Jihad, the AFFS shifted to a defensive mindset. Though it still had several RCTs on the rolls, the majority of the units were rebuilt as Light Combat Teams. Smaller versions of the AFFS' traditional RCT, the LCT was a reinforced battalion of 'Mechs (typically three companies plus a two-to-three lance command company), two to three battalions of heavy and assault armor, an equal number of cavalry battalions, and an artillery company. Additionally the LCT includes a include a regimental-size Battle Armor formation (though in most cases the size is much smaller) and VTOL assets to provide transportation for the Battle Armor as well as reconnaissance for the LCT. The large conventional infantry forces of the RCT have been reduced to those troops needed to provide engineering, security, and other support roles.
 Larger Formations
Though no longer in common use, there are several larger formations that military planners accept as common terms.
A Brigade is a military formation typically consisting of 3 or more regiments, usually of similar weight classes and capabilities. This formation was used extensively by the SLDF, but is no longer used by most Inner Sphere militaries. Brigades were usually commanded by a Lieutenant General and limited to being no more than five regiments in size for administrative purposes. Some Regimental Combat Teams were also categorized as brigades.
Examples of BattleMech brigades include the Eridani Light Horse, Northwind Highlanders, Deneb Light Cavalry, or the Sword of Light. The Armor and Infantry units of the Federated Sun's Regimental Combat Teams are also referred to as brigades.
A Division is a grouping of three brigades, as well as reserves, support units, and an ASF Wing. They were commanded by a Major General or General. The Division was the heart of the SLDF, and were typically assigned to protect a group of star systems within one jump radius of each other, or a particularly important planet. There are no division-sized formations known to exist in the Inner Sphere.
The ComGuards use the term Division to refer to their Level IV units, which consist of 216 combat units. In reality these units are approximately the size of two mixed regiments of Mechs, conventional armor, and infantry.
Used only by the SLDF, a Corps was a group of military forces that defended between 30 and 100 worlds. Unlike regiments, brigades, and divisions, there was no "standard" or "typical" corps. They typically consisted of one to three BattleMech Divisions, two to seven infantry divisions, several independent regiments, and enough WarShips and transport JumpShips to move the entire unit. Each Star League Member State hosted between one and four Corps-sized units.
Later military planners would consider a corps a group of five to ten divisions, but didn't organize them by type (infantry, BattleMech, etc.).
As units of this size became impossible due to the damage of the Succession Wars, the term fell out of common military parlance until the Com Guards reactivated it to describe their Level V units. These units, like the SLDF Corps and Armies that preceded them, covered large parts of each of the Successor States, each of the then-twelve armies covering an "hour" on the "Inner Sphere Clock". Unlike the SLDF, a Com Guard Army is mostly an administrative term. The Battle of Tukayyid and Operation SCOUR were the only times ComStar deployed Army-sized formations in combat.
Typically an Army consisted of three to five Corps.
While the BattleMech organizational structure is common, there are two other unit types that engage in combat operations both in space and on the ground.
As mentioned earlier, aerospace units are half the size of BattleMech units (a lance has two fighters as opposed to four 'Mechs). DropShips and JumpShips are normally not grouped together, but are treated as independent support troops.
Typical Inner Sphere formation consisting of 2 - Aerospace Fighters, Coventional, VTOLs, WIGE type craft.
Typical Inner Sphere formation consisting of 6 units or airborne vehicles. Consisting of 3 flights. This does not include a Command Flight for the unit's commanding officer.
Typically Battalion size formation, consisting of 18 airborne vehicles. Not counting a Command Flight of 2 additional aerospace vehicles.
Consisting of 2 - 3 Wings of airborne vehicles, including Command Flight.
Infantry is divided into slightly different organizational units that can be integrated into traditional BattleMech units. The structure of an infantry unit is shown below:
- Fire team - consists of three to five individuals
- Squad - comprised of two fire teams and a squad leader (seven to twelve individuals)
- Platoon - comprised of two or more squads plus support personnel (twenty-five to fifty individuals). In the 3025 time period the standard platoon had one support weapons squad and three "line" squads.
- Company - comprised of two or more platoons (seventy to over two hundred individuals)
- Battalion - comprised of two to six companies (three hundred to one thousand individuals)
Combat in the thirty-first and thirty-second centuries has placed far less emphasis on infantry than previous conflicts so it is unusual to see infantry units larger than a company in size. It is common for squads and platoons to support BattleMech operations and to perform general patrol and scout duties.
 Battle Armor
Infantry units equipped with Battle Armor are organized differently from their conventional counterparts, due to their increased combat performance. Organized similarly to BattleMech units, Battle Armor units use the following structure.
- Squad - consists of four battle armored infantry.
- Platoon - consists of three squads and support elements.
- Company - consists of three platoons and support elements.
- Battalion - consists of three companies and support elements.
- ↑ BattleTech, 2nd Edition
- ↑ Field Manual: Capellan Confederation, p. 36
- ↑ BattleTech, 2nd Edition
- ↑ Field Manual: Capellan Confederation, p. 36
- ↑ 5.0 5.1 Total Warefare, p. 34 - Organization - Lance/Battalions/Platoons - Flight description.
- ↑ Field Manual: 3085, pp. 19-20
- ↑ Mercenary's Handbook, p. 68
- ↑ House Davion (The Federated Suns), p. 81
- ↑ House Davion (The Federated Suns), p. 126
- ↑ Field Manual: Federated Suns, p. 18
- ↑ Field Report: AFFS, p. 5
- ↑ 12.0 12.1 12.2 12.3 Total Warfare, p. 35
- ↑ 13.0 13.1 13.2 13.3 The Star League, p. 133
- ↑ Total Warfare, p. 214 - "Battle Armor Organization"