text: Tactical Control Measures
  COORDINATING ALTITUDE
  A-107. A coordinating altitude is an airspace
  coordinating measure that uses altitude to
  separate users and as the transition between
  different airspace control elements (JP 3-52).
  The establishment of a coordinating altitude
  allows the airspace control authority to assign a
  volume of airspace to another airspace control
  organization. Army forces must be aware that
  any airspace user that transits or fires through an
  established coordinating altitude must
  coordinate with the appropriate airspace control
  agency. For example, all artillery fires that
  exceed the coordinating altitude must be
  coordinated and approved prior to execution.
  The coordinating altitude is normally expressed
  in feet above mean sea level.
  A-108. The joint force airspace control
  authority establishes the coordinating altitude,
  typically after consultation with the other
  Service components. The airspace control
  authority publishes the coordinating altitude as
  part of the airspace control order. Army forces Figure A-52. Coordinating altitude and
  can request adjustments to the coordinating coordination level
  altitude based on mission requirements for
  approval by the airspace control authority. Typically, the only echelon that does this is a division if has a
  joint air-ground integration center. Figure A-52 depicts a coordinating altitude of 13,000 feet mean sea level.
  COORDINATION LEVEL
  A-109. A coordination level is an airspace coordinating measure below which fixed-wing aircraft by
  normally will not fly (JP 3-52). The coordination level and coordinating altitude are not synonymous terms.
  The key distinction being that a coordination level is used to separate fixed- and rotary-wing aircraft while a
  coordinating altitude is used to separate different airspace control elements. Additionally, a coordination level
  can be established with or without a coordinating altitude. Army forces recommend a coordination level, or
  any adjustments to an existing coordination level to the airspace control authority for approval. BCTs and
  above can initiate a request for a coordination level within their air defense airspace management/brigade
  aviation element cell or joint air-ground integration center. A coordination level is established by the airspace
  control authority and is reflected in the airspace control order. The coordination level is normally expressed
  in feet above ground level. Figure A-52 depicts a coordination level.
  RESTRICTED OPERATIONS ZONE
  A-110. A restricted operations zone is airspace reserved for specific activities in which the operations of
  one or more airspace users is restricted (JP 3-52). A restricted operations zone (ROZ) ACM has fourteen
  specific uses. Example uses include close air support and unmanned aircraft.
  Close Air Support ROZ
  A-111. A close air support ROZ is airspace designated for holding orbits and is used by rotary- and fixed-
  wing aircraft in proximity to friendly forces. This ROZ is used in support of air assets performing close air
  support missions in support of ground maneuver forces. When determining the appropriate ROZ size units
  need to consider the type of aircraft providing support and altitude limits This ROZ is requested by the
  applicable ground maneuver force and is established by the airspace control authority.