text: Chapter 5
  Figure 5-12. Zone reconnaissance technique during moving flank security mission
  COVER
  5-93. A cover is a type of security operation done independent of the main body to protect them by fighting
  to gain time while preventing enemy ground observation of and direct fire against the main body (ADP 3-90).
  Commanders use the cover task offensively and defensively. A cover is a brigade-level, force-oriented
  mission that protects the division or corps main body from detection or engagement by enemy forces
  attempting to delay or disrupt friendly operations. A covering force may be offensive or defensive in nature.
  The nature of the cover mission reflects the type of operation conducted by the division or corps. All covering
  force operations are aggressively executed making maximum use of offensive opportunities. A covering force
  accomplishes all the tasks of screening and guard forces. (Refer to FM 3-90-2 for more information.)
  5-94. A covering force is an independently operating, self-contained force conducting the cover mission.
  The covering force operates away from the main body to develop the situation, prevent enemy ground
  observation, and protect the main body from direct and indirect fires. METT-TC (I) factors determine the
  distance from the main body. To protect the main body from effective ground observation and direct fires,
  the BCT may execute operations as far as 50 to 60 kilometers from the main body. The covering force denies
  the enemy information by conducting counterreconnaissance to destroy enemy reconnaissance and enemy
  forces within the security zone. A covering force develops the situation earlier than a guard force, fights
  longer and more frequently, and defeats larger enemy forces than a guard force. Furthermore, a covering
  force reconnoiters, screens, attacks, defends, and delays as necessary. The covering force does not allow
  enemy forces to bypass and affect the main body.