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ACO

GENERAL. 

The Airspace Control Order (ACO) is developed from the Airspace Control Plan (ACP). It directs the use of joint airspace and details the approved requests for airspace control measures for specified periods. The ACO lists, but is not limited to, airspace control measures (ACMs) and procedures used on or over the area of operations. It is critical to mission success that airspace users receive pertinent airspace information as early in the planning cycle as possible. A change to the ACO should be distributed whenever a new area is established or an existing area deleted. 

ACO Header 

Decode the ACO header. See example below: 

OPER/COBRA GOLD 07/C2WS/ATOTRNG/-// 
MSGID/ACO/C2WS/705401/FEB/CHG/02// 
REF/A/ACMREQ/ABCCC/23FEB2007/-/-/-// 
REF/B/ACMREQ/CTG50.21/230800ZFEB2007/002/-/-// 
ACOID/COBRA GOLD AO/23B// 
GEODATUM/WGS 1984// 
PERIOD/230600FEB2007/240559FEB2007// 
GENTEXT/ACO MANAGEMENT INFORMATION/IDENTIFY 
PROBLEMS PERTAINING TO THIS ACO TO THE JAOC 
AIRSPACE MANAGEMENT CELL AT DSN 123-4567///-// 

Decode the first dataset of the header. It identifies the type of message being received. 

OPER/COBRA GOLD 07// 
EXER/OFF 450 FTU TRAINING// 
•

    Field 1 – Notice that the dataset identifier will be either OPER or EXER indicating the reason for the
    message, followed by a "/".
    • Field 2 – The second element in this dataset is the nickname of the exercise or operation codeword
    itself; "COBRA GOLD". 

    For an EXER there may be one additional data block to display any additional identifiers for the exercise,
    and then a double slash (//) to end the dataset. 

    Decode the second dataset in the header. It contains the Message Identification (MSGID). 

    MSGID/ACO/C2WS/705401/FEB/CHG/02// 
    •

      Field 1 – Message Text Format Identifier. This field must equal "ACO" when it is an ACO message.
      • Field 2 – Originator or Issuing Agency  
      • Field 3 – Message Serial Number. If the ACO is numbered it would be indicated here.
      • Field 4 – Month name. The presence of a month name does NOT by itself imply the ACO is valid
      for the entire month.
      • Field 5 – Qualifier. If this is a change it would indicate "CHG" here.
      • Field 6 – Qualifier Serial Number. Indicating which change number it is. Much of the information in
      these blocks may be "-" indicating a "no data" entry. 

      Decode the next dataset which is the ACO Identification, area, and version. 

      ACOID/COBRA GOLD AO/23B// 

      This dataset is MANDATORY if the message identification is "ACO". 

        Field 1 – Area of Validity. This area is optional and can indicate a geographical area or a command over which the ACO is valid. Field 2 - ACO Serial Number. 

        NOTE: The serial number shall be a number between 01 and 31. It may be followed by a letter. Serial numbers were obviously intended to mirror the day of the month and the alphabetical letters were intended to identify multiple versions in a day. 

        GEODATUM/WGS 1984// 

        The Geodetic Datum reference used throughout the document. The geospatial datum is a critical field which ensures everyone is using the same map reference and coordinate systems. 

        PERIOD/230600FEB2007/240559FEB2007// 

        PERIOD set defines the period covered by the ACO.

          Field 1 – Start day-time, month and year  Field 2 – Stop day-time, month and year 

          GENTEXT/ACO MANAGEMENT INFORMATION/IDENTIFY// 

          GENTEXT indicates the contents of the data element will be in a general text format to provide more information about the ACO, in this case ACO management information. 

          ACM blocks 

          ACMs in the ACO are shown in USMTF format. They are depicted in nested sets of ACM information, and each individual ACM may have various combinations of any or all of the following sets. 

          ACMID/ACM:CORRTE/NAME:BUICK/CORRIDOR/USE:AIRCOR// 

          The Airspace Control Means Identification (ACMID) dataset identifies and defines the type and usage of the airspace coordinating measure, as in the following lines.

            Field 1 – ACM type Field 2 – ACM name (NAME) or designator (DESIG). ACM naming or numbering may be regulated or restricted by the ACA via instructions in the ACP. Field 3 – ACM shape. This is a hugely important block as it will prompt the system to generate the dataset tables which define the coordinates, radii, arcs, or diameter of the ACM shape. Possible entries are limited to the following:
              POLYARC. A polyarc is basically a shape composed of a single arc and another group of points making up the shape.  RADARC. A radarc is a shape commonly seen on radar scopes to create minimum vectoring altitude areas. It is an inner arc connected via radials to an outer arc.   CORRIDOR. A corridor is a sequence of points set one after the other and having a fixed width. POLYGON. A polygon is a set of nonarcing points enclosing a shape.   CIRCLE. A shape with a fixed radius around a single point.   TRACK. A track is like a corridor except the width can vary on either side of centerline for each leg and each leg can have a different altitude.   POINT. A single point.   ORBIT. An orbit is a set of two points forming a route which aircraft maintain a circuit around.   LINE. A series of points having no width. Field 4 – ACM usage  

              GEODATUM/WGS 1984// 

              GEODATUM dataset is only used if the geodetic data standard used for the ACM is different than the standard cited in GEODATUM dataset in the ACO header. If the same geodetic datum was used this field will not appear. 

              SHAPE/CORRIDOR// 

              SHAPE dataset format was determined when the shape name was entered in field 3 of the ACMID dataset. 

              EFFLEVEL/RARA:000AGL-020AGL//  
              EFFLEVEL/FLFL:FL250-FL290// 

              Vertical dimension of the effective level dataset defines the altitudes at which the ACM applies. 

              APERIOD/INTERVAL/131325ZNOV/132359ZNOV/WEEKLY/4WK// 

              APERIOD (Airspace Time Period) dataset defines when the ACM is effective. 

                Field 1 – Airspace time mode Field 2 – Start day-time and month Field 3 – Stop day-time and month Field 4 – Interval frequency. This field is used only if the airspace time mode is “INTEVAL”. Field 5 – Interval duration. This field is used only if the airspace time mode is “INTEVAL”. 

                CONTAUTH/RHEIN MAIN CP/125.25MHZ/341.25KHZ// 

                CONTAUTH (Controlling Authority) defines which is the controlling authority for the ACM. 

                  Field 1 – Authority call sign or name Field 2 – Primary frequency or designator  
                  Field 3 – Secondary frequency or designator
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