The warrant officer rank in the South Korean armed forces falls in between that of non-commissioned and commissioned officers. In the ROK Navy, warrant officers are mostly former non-commissioned officers who had earned the rating of "Sangsa" (Chief petty officer) or "Wonsa" (Master chief petty officer) and who had been selected for and completed the warrant officer candidate program. Other routes include the naval aviation program and Air Intercept Controller (AIC) program; a small number of warrant officers serve as language officers who specialize in English translation and interpretation.