Army and Royal Marines In the
British Army,
Royal Marines, and many other
Commonwealth military and
paramilitary organisations, the commanding officer of a unit is appointed. Thus the office of CO is an appointment. The appointment of commanding officer is exclusive to commanders of major units (
regiments,
battalions and similar sized units). It is customary for a commanding officer to hold the rank of
lieutenant colonel, and they are usually referred to within the unit simply as "the colonel" or the CO. "The colonel" may also refer to the holder of an honorary appointment of a senior officer who oversees the non-operational affairs of a regiment. However, the rank of the appointment holder and the holder's appointment are separate. That is, not all lieutenant colonels are COs, and although most COs are lieutenant colonels, that is not a requirement of the appointment. Sub-units and minor units (
companies,
squadrons and
batteries) and formations (brigades, divisions, corps and armies) do not have a commanding officer. The officer in command of a minor unit holds the appointment of
officer commanding (
OC). Higher formations have a commander (e.g. brigade commander) or a
general officer commanding (GOC). Area commands have a commander-in-chief (e.g. C-in-C Land Army, C-in-C British Army of the Rhine). The OC of a sub-unit or minor unit is today customarily a
major (although formerly usually a
captain in infantry companies and often also in cavalry squadrons), although again the rank of the appointment holder and the holder's appointment are separate and independent of each other. In some cases, independent units smaller than a sub-unit (e.g. a military police platoon that reports directly to a formation such as a brigade) will also have an OC appointed. In these cases, the officer commanding can be a captain or even a lieutenant. The commanders of administrative organisations, such as schools or wings, may also be designated officers commanding or commanders. Appointments such as CO and OC may have specific powers associated with them. For example, they may have statutory powers to promote soldiers or to deal with certain disciplinary offences and award certain punishments. The CO of a unit may have the power to sentence an offender to 28 days' detention, whereas the OC of a sub-unit may have the power to sentence an offender to three days' restriction of privileges. Commanders of units smaller than sub-units (e.g.
platoons,
troops and
sections) are not specific appointments and officers or NCOs who fill those positions are simply referred to as the commander or leader (e.g. platoon commander, troop leader, section commander/leader, etc.).
Air force In the
Royal Air Force, the title of commanding officer is reserved for station commanders or commanders of independent units, including flying squadrons. As with the British Army, the post of a commander of a lesser unit such as an administrative
wing,
squadron or
flight is referred to as the officer commanding (OC).
Navy In the
Royal Navy and many others, commanding officer is the official title of the commander of any ship, unit or installation. However, they are referred to as "the captain" no matter what their actual rank, or informally as
"skipper" or even "boss". ==United States==