The Governor, on recommendation of the Adjutant General, shall appoint at least one (1) Assistant Adjutant General for Army and at least one (1) Assistant Adjutant General for air and such other assistant adjutants general as may be authorized by rules and regulations of the National Guard Bureau of the United States of America. Each shall have the rank of Brigadier General, or higher, if authorized by the National Guard Bureau of the United States of America. Each shall remain in office during the pleasure of the Governor, and shall be entitled to all the rights, privileges and immunities granted officers of like rank in the Mississippi National Guard. Each shall, before entering upon the duties of their office, take and subscribe to the oath of office prescribed for officers of the Mississippi National Guard, which oaths shall be deposited in the office of the Adjutant General. Each shall aid the Adjutant General by the performance of such duties as may be assigned him. In the case of death, absence or inability of the Adjutant General to act, the senior full-time Assistant Adjutant General shall perform the duties of the Adjutant General until the Adjutant General shall resume his duties or until a successor shall be appointed. To be qualified for appointment as Assistant Adjutant General, a person must at the time of his appointment possess the same qualifications required of the Adjutant General.