The 5900 electronics maintenance OccFld maintains, operates and repairs organic communication and electronic equipment within the Marine Air Command and Control Systems (MACCS), Marine Aircraft Wings. The MACCS contains sophisticated and modern equipment and systems which include: air defense and surveillance radar systems, aviation radio communication systems, air traffic control systems, and command and control tactical data systems. Accordingly, OccFld 5900 personnel must achieve and maintain a high level of technical competence, knowledge, and skills necessary to maintain and operate complex electronic, data, computer, communication, and radar systems. The opportunity to participate in a formal apprenticeship program leading to a Department of Labor Certificate of Apprenticeship Completion may be available in some MOSs within OccFld 5900. Many skills acquired in the 5900 OccFld are directly transferable to civilian occupations upon leaving the military service. Marines entering this OccFld will receive formal courses of instruction in Basic Electronics followed by detailed instruction involving specific electronic, data, communication, or radar systems. After completion of formal training, a MOS will be assigned which designates a specific job in the electronics maintenance field within the Marine Air Command and Control Systems of the Marine Aircraft Wing.