text: Fire Support Coordination Measures
  B-5. FSCLs facilitate the expeditious attack of surface targets of opportunity beyond the coordinating
  measure. The FSCL is not a boundary-the synchronization of operations on either side of the FSCL is the
  responsibility of the establishing commander, out to the limits of the land or amphibious force boundary. The
  FSCL applies to all fires of air, land, and sea-based weapon systems using any type of ammunition. The
  JFLCC and JFMCC cannot employ fires long of the FSCL without coordination with affected commanders,
  and the JFACC cannot employ fires short of the FSCL without coordination with the JFLCC or JFMCC.
  Supporting elements attacking targets beyond the FSCL must ensure that the attack will not produce adverse
  effects on, or to the rear of, the line. The appropriate land or amphibious force commander controls all air-
  to- ground and surface-to-surface attack operations short of a FSCL. The FSCL should follow well-defined
  terrain features to assist identification from the air. Coordination of attacks beyond the FSCL is especially
  critical to commanders of air, land, and SOF. For more information on coordination of attacks beyond the
  FSCL see JP 3-09.
  B-6. Establishing a FSCL close-in, yet at sufficient depth to not limit the tempo of maneuver forces, eases
  target engagement coordination requirements within their areas of operations by forces that may not be under
  their direct control. The commander adjusts the location of the FSCL as required to keep pace with operations.
  In large-scale combat operations, the FSCL will change frequently. The JFC should establish a time standard
  and guidance for shifting an FSCL.
  B-7. The FSCL is a term oriented to land and airspace operations and is normally located only on land. In
  certain situations, such as littoral areas, the FSCL may affect both land and sea areas. If possible, the FSCL
  should follow well-defined terrain features to assist identification from the air. The commander of the landing
  force normally establishes the FSCL for amphibious operations. Changes to the FSCL require notification of
  all affected forces within the AO and must allow sufficient time for these forces to incorporate the FSCL
  change. When friendly forces are operating beyond the FSCL restrictive FSCMs such as RFAs and NFAs
  should be employed to protect those forces.
  B-8. A solid black line extending across the assigned areas of the establishing HQ provides the graphic
  portrayal of the FSCL (see figure B-2 on page B-4). The letters "FSCL" followed by the establishing HQ are
  annotated above the line, and the effective date-time-group below the line. FSCLs do not have to follow
  traditional straight-line paths. Positioning the FSCL on terrain identifiable from the air is a technique that
  may further assist in fratricide prevention. Curved or enclosed FSCL have applications in joint operations
  conducted in non-contiguous areas of operation.