A CFAV, or Cadet Force Adult Volunteer, is the official name given to any non-commissioned adult instructor within the Army Cadet Force, regardless of rank.

CFAVs are not paid for general parade night training, however will be reimbursed petrol if their journey exceeds 3 miles. For training weekends and camps, they are paid at a rate dependent on rank.

The non-commissioned rank structure of adult volunteers goes as follows-

Civilian Assistant (CA). CA's are not technically CFAVs and are unpaid with the exception of petrol reimbursement.
Potential Instructor (PI). This is the first paid rank, where an applicant has completed the relevant paperwork to become a CFAV, but has yet to finish their initial training. Rate of pay is little above minimum wage.
Sergeant Instructor (SI). This rank is automatic on successful completion of training.
Staff Sergeant Instructor (SSI). Also know as Colour Sergeant in infantry-affiliated units.
Sergeant Major Instructor (SMI). Both classes of warrant officers fall under this title, with the exception of the RSM.
Regimental Sergeant Major Instructor (RSMI). Unlike the cadet forces, in the regular forces, RSM is a role held by a WO1 as opposed to being a rank in its own right.

Any rank above these requires a commission from the Cadet Force Commissioning Board, which takes the same format as a regular officer selection board despite being far less stringent.