Marines and Sailors with the National Naval Officer Association listen to sergeants major and command master chiefs during a professional military education class aboard Marine Corps Air Station Miramar, Calif., Nov. 18. The class was held to help the junior and mid-grade officers better understand the role a senior enlisted advisor has and how they can help. - Marines and Sailors with the National Naval Officer Association listen to sergeants major and command master chiefs during a professional military education class aboard Marine Corps Air Station Miramar, Calif., Nov. 18. The class was held to help the junior and mid-grade officers better understand the role a senior enlisted advisor has and how they can help.