Cadet Under Officer

Under officer is an appointment held by the most senior cadets at some Commonwealth officer training establishments and in University Officers' Training Corps in the United Kingdom, and also a rank used in some Commonwealth cadet forces.

The Royal Military College, Duntroon uses the appointments of senior under officer and under officer for senior Staff Cadets.

In the Australian Army Cadets and Australian Air Force Cadets, the rank of Cadet Under Officer (abbreviated in writing to 'CUO') is the highest cadet rank. They are saluted and addressed as "Sir" or "Ma'am" by their subordinates but not by adult officers or instructors or members of the Australian Defence Force.

AAC cadet under officers may be assigned as national, regional, or battalion under officer, as quartermaster, or as the commander of a company or platoon. The rank badge is a lozenge, which contains 27½ chevrons. The national cadet under officer has red in the centre of the lozenge. Regional cadet under officers have blue in the centre of the lozenge.

To become a cadet under officer, a cadet must have completed the senior leaders course module two, otherwise known as the CUO/WO course, often held either at a mid or end of year session. The course runs for one week on a military base, and during this course a prospective cadet under officer will learn platoon and company level command. To gain entry to the course the cadet must have successfully completed the senior leaders course module one or the sergeant course, which entitles them to bear ranks up to staff sergeant.

The insignia for an Australian Air Force Cadet (AAFC) cadet under officer is a thick white stripe.

To achieve the rank of cadet under officer, an AAFC cadet sergeant, cadet flight sergeant or cadet warrant officer must complete the cadet under officer course, which typically takes 3 weeks at a Royal Australian Air Force base in their home state. Upon successful completion of the cadet under officer course, cadet under officers are given full Officer privileges, which includes the right to use the officers' mess on military establishments.

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