History: Below is a listing of the Revisions and Changes made to this UFGS.
| KEY | PREPARING ACTIVITY (PA) | A Army | N Navy | F Air Force | S NASA [ARCHIVED] |
|---|---|---|---|---|---|
| ACTION | N New | R Revision | C Change | D Deletion |
| Release | PA | Date | Action | Change # | Nature of Change or Revision |
|---|---|---|---|---|---|
| Nov-2021 | N | Nov-2021 | N | New unified section superseding UFGS-27 21 00.00 20, UFGS-27 21 00.00 40, and UFGS-27 51 23.10 all titled INTERCOMMUNICATION SYSTEM. |
