text: _________________________________________________________________________________Chapter 9
  Other Survivability Measures
  9-108. Other measures taken to improve the security and survivability of air
  defense systems include the following:
  • Signals security. SAM and AA gun system radars, which move forward
  to cover the offensive or defensive action of a maneuver unit, remain
  silent until after the maneuver unit begins to execute its mission.
  • Frequency spread. Each of the air defense systems operates within
  separate radar frequency bands. (No one jamming system could oper-
  ate simultaneously against all bands.)
  • Frequency diversity. Tracking and guidance radars change frequen-
  cies to overcome jamming.
  • Multiple and interchangeable missile guidance systems. Some
  OPFOR systems work on pulsed radar; others work on continuous
  waves. Some radar tracking systems also possess optical tracking for
  continued operations in a high electronic countermeasures environ-
  ment; others systems use IR homing.
  • Mobility. All OPFOR tactical air defense systems and most opera-
  tional-level systems are mobile. They can quickly change positions af-
  ter firing or after enemy reconnaissance units detect them.
  RECONNAISSANCE
  9-109. Reconnaissance related to air defense takes two basic forms. First,
  commanders conduct terrain reconnaissance to determine likely avenues of
  approach for enemy aircraft and optimum positions for air defense weapons.
  Then air surveillance seeks to detect approaching aircraft and provide early
  warning and target information.
  TERRAIN RECONNAISSANCE
  9-110. The OPFOR places significant emphasis on identifying all potential
  attack routes for low-flying enemy aircraft of all types. Routes of approach suit-
  able for armed helicopters and positions from which these helicopters might em-
  ploy ATGMs are of special concern. The OPFOR considers armed helicopters to
  be a serious threat to its ground maneuver units. The OPFOR trains command-
  ers to look for areas masked by trees or folds in the terrain where enemy aircraft
  might use nap-of-the-earth (NOE) flight techniques to avoid radar detection.
  9-111. Both the commander of the supported maneuver unit and the com-
  mander of the supporting air defense unit usually conduct terrain reconnais-
  sance. A preliminary map reconnaissance can tentatively identify positions
  for deployment of air defense weapons in defensive areas, along movement
  routes, or in areas seized by advancing OPFOR units.
  AIR SURVEILLANCE
  9-112. The principle objective of air surveillance is to provide the earliest
  possible warning of approaching enemy aircraft and to develop target informa-
  tion for planning and conducting air defense. Forearmed with this information,
  the OPFOR can ensure that it can mass the fires of dispersed air defense
  units to engage the intruders. Ground-based and airborne reconnaissance assets