READ BELOW BEFORE CONTINUING

See Section 4, Estimated Completion Date, of the "Change Document" (Modification Note, Maintenance Note, Software Note, TCTO, etc.) to determine how many days from the Effective Date you are allowed to implement the configuration change.

The Effective Date is not:

  • The same as the Issuance Date.
  • The same as the Date Signed.

The Effective Date of a change document is determined by the nature of the modification.

  • For hardware modifications requiring additional materials, the Effective Date is established as the date that the kit is shipped from the warehouse. All sites will probably not have the same shipping date.


  • For modifications & maintenance notes not requiring additional materials, the Effective Date is:
    • (NWS Only) the date the site receive EMRS notification to implement the change.

    • OR
    • (DOD & FAA) the date the document “hardcopy” is mailed to each site.


  • For software modifications, the Effective Date is established as the date that software is shipped from the ROC.


  • For modifications that are linked to other activities such as PMI team visit, depot level installation of related hardware, etc., the Effective Date is established in accordance with the schedule for the pre-requisite activity. Note that site personnel are responsible for reporting completion of the modification even if it is implemented by an outside activity. In this instance, the text of the change document will identify the specific circumstances.

Implementation of change documents must be reported in a timely manner.

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