Forward air control is the provision of guidance to Close Air Support (CAS) aircraft intended to ensure that their attack hits the intended target and does not injure friendly troops. This task is carried out by a forward air controller (FAC). For NATO forces the qualifications and experience required to be a FAC are set out in a NATO Standard (STANAG). FACs may form part of a Fire Support Team or Tactical Air Control Party, they may be ground based, airborne FACs in fixed wing aircraft (FAC-A) or in helicopters (ABFAC). Since 2003 the United States Armed Forces have used the term joint terminal attack controller (JTAC) for some of their ground based FACs.