• • Flash Requests for news of aircraft in flight, flight plans,  or  cancellation  messages  to  prevent unnecessary search and rescue action Reports of weather observations of wind speeds of 34 knots or greater The precedence Flash (prosign Z) is reserved for initial enemy contact reports of operational combat messages  of  extreme  urgency.  The  following  are examples of reports assigned this precedence: • • • • • Initial enemy contact reports Messages recalling or diverting friendly aircraft about to bomb targets unexpectedly occupied by friendly  forces Warnings of imminent large-scale attacks Messages containing major strategic decisions of great urgency Reports  of  tropical  storms,  typhoons,  or hurricanes believed to be previously undetected (Unit commanders may use Flash precedence for such reports if no extenuating circumstances would jeopardize the tactical situation.) DELIVERY TIME Because  precedence  is  assigned  according  to desired writer-to-reader time, you should be aware of elements that affect message delivery time, such as the following: • • • • • • Types of telecommunications facilities Number of messages processed Telecommunications equipment speed Message length Number of addressees Telecommunications circuit conditions The following lists the speed-of-service objectives of each precedence: PRECEDENCE Flash Immediate Priority Routine SPEED OF SERVICE PROSIGN OBJECTIVE Z As fast as possible with an objective of less than 10 minutes O 30 minutes P 3 hours R 6 hours DATE-TIME GROUP A date-time group (DTG) is assigned to a message for identification and file purposes only. The DTG is a universal date-time reference system expressed in Greenwich Mean Time (GMT). The date-time group is a six-digit number suffixed by the letter Z, which indicates GMT. The abbreviated month and year are appended to the DTG. The first two digits of the date-time group indicate the date; the next four digits the GMT. For example, 071246Z APR85 indicates 7 April 1985, 1246 GMT. CLASSIFICATION Each classified message must have its classification listed on the classification line of the message. The first word of the classification line must be one of three classification designators or the word “UNCLAS.” The three classification designators are CONFIDENTIAL, SECRET, and TOP SECRET. The acronyms FOUO (For Official Use Only) and EFTO (Encrypt  for  Transmission  Only)  are  not classifications but can be used with UNCLAS in the classification line. Likewise, the terms Restricted Data and Formerly Restricted Data, while not classifications,  can  be  used  with  classification designators. The proper spelling and spacing of these terms are as follows: UNCLAS UNCLAS EFTO FOUO C O N F I D E N T I A L S E C R E T T O P    S E C R E T 8-14