text: Fire Support Coordination Measures
  Figure B-20. Common sensor boundary example
  SECTION V – AIRSPACE CONTROL
  B-76. Airspace control increases operational effectiveness by promoting the safe, efficient, and flexible use
  of airspace while minimizing restraints on airspace users. Airspace control includes coordinating, integrating,
  and regulating airspace to increase operational effectiveness.
  B-77. Airspace control is essential to overall military effectiveness and in achieving JFC objectives. Given
  the speed, range, and physical characteristics of air operations, ACMs are integrated into operations to
  deconflict airspace users and decrease the potential for unintended engagements against friendly, civil, and
  neutral aircraft. For more information on airspace control see JP 3-52.
  AIRSPACE COORDINATING MEASURES
  B-78. A key to effectively coordinating joint fires is to constantly view the OA as a three-dimensional area.
  ACMs are nominated from subordinate HQ through component command HQ and forwarded to the airspace
  control authority in accordance with the airspace control plan. Airspace coordinating measures are measures
  employed to facilitate the efficient use of airspace to accomplish missions and simultaneously provide
  safeguards for friendly forces (JP 3-52).
  B-79. Most ACMs affect direct and indirect joint fires trajectories and UAS because of their airspace use.
  The establishment of ACMs in coordination with FSCMs results in the most efficient use of airspace for all
  friendly airspace users. Some ACMs may be established to permit surface joint fires or UAS operations. The
  component commanders ensure that ACMs nominations support and do not conflict with joint operations
  prior to forwarding the nominations to the joint AOC. The airspace control authority approves formal ACM
  nominations and includes them in the ACO. The airspace control authority is the commander designated for
  overall responsibility for airspace control (JP 3- 52).