TECHNICAL DIRECTIVE UPDATING METHODS Sometimes,  a  change  or  bulletin  is  not  the complete answer to a problem, and it is necessary to amend or revise a current directive. An amendment clarifies, adds to, deletes from, makes  minor  changes  to,  or  cancels  an  existing technical  directive.  It  only  supplements  the  existing directive and not a complete directive in itself. A maximum of three amendments may be applied to a TD,  each  remaining  in  effect  until  rescinded  or superseded. A requirement for further amendment action requires the issuance of a revision. A revision is a completely new edition of the existing directive. It supersedes the original directive or revision and all existing amendments. TECHNICAL DIRECTIVES (RESCISSION/SUPERSEDURE/ CANCELLATION/AMENDMENT) In   this   section,   rescissions,   supersedures, cancellations, and amendments are discussed. A rescission is the process by which TDs are removed from active files after requirements have been incorporated. Final rescission action is directed in  NAVSUP  2002.  Activities  maintaining  active technical libraries should maintain the TDs on file until they are deleted from the NAVSUP 2002 index. A supersedure is the process by which interim changes are removed from active files after a formal TD has been issued. A cancellation is the process by which a TD is removed from the active files. A TD is canceled if it is determined that a previously issued TD is not to be incorporated. TDs are canceled by an amendment to the TD. The cancellation explicitly states the required configuration of each article initially specified for modification;   for   example,   whether   installed modifications are to remain installed or whether they are to be removed. TD TITLES AND NUMBERING There are many title subjects of changes and bulletins. A few example titles are as follows: Power  Plant  (PPC,  PPB)—The  last  letter identifies the TD as a change (C) or bulletin (B) Avionics (AVC, AVB) Aviation armament (AAC, AAB) Support equipment (SEC, SEB) Airborne weapon (AWC, AWB) Accessory (AYC, AYB) The following are examples of the numbering system: Aviation Armament Change No. 537 Support  Equipment  Change  No.  1299 F- 14 Interim Airframe Change No. 261 F- 14 Interim Airframe Bulletin No. 111 The numbering system is a consecutive numerical application. For example, Avionics Change 204 would be the 204th avionics change issued. The numbers assigned to changes and bulletins are provided by the Technical Directive Control Center, which is located at the Naval Air Technical Services Facility (NATSF). Changes or bulletins that have been amended will have their basic number followed by the words  “Amendment  1,”  “Amendment  2,”  etc.  A revised directive will have the basic directive number followed  with  the  words  “Rev.  A.”  “Rev.  B,”  as appropriate, to denote the first or second revision to that basic directive. The  changes  and  bulletins  are  automatically distributed to the concerned activities. All TDs are issued by NAVAIR or NATSF, except in cases where the time delay in obtaining approval is unacceptable. In  such  cases,  the  controlling  custodians  are authorized  to  issue  interim  TDs  to  prevent unacceptable risks to personnel or equipment. The changes or bulletins are generally based on contractor service bulletins, other letters of recommendations, or proposed modifications from field service activities. TECHNICAL DIRECTIVE CATEGORIES Technical  directives  are  assigned  a  category according  to  the  importance  and  urgency  of accomplishing  the  work  involved.  A  category  of immediate,  urgent,  routine,  or  record  purpose  is assigned to each technical directive. Immediate   action   TDs   are   issued   when   an uncorrected, unsafe condition exists that could result in fatal or serious injury to personnel, or extensive damage to or destruction of valuable property. These unacceptable  risks  require  immediate  action  to  either ground aircraft, prevent launch of missiles, or deny use of related support equipment or munitions. 2-32