text: Reconnaissance
  12-61. Commanders employ aerial reconnaissance when required by the mission variables. However, aerial
  reconnaissance can rarely clear enemy forces from locations where they can affect movement on these routes
  and aircraft cannot breach obstacles. When time is limited, aerial reconnaissance is essential to determine
  which areas are clear of enemy forces and obstacles. Aerial reconnaissance can also cue ground
  reconnaissance assets regarding where to focus their efforts.
  Control Measures Associated with a Route Reconnaissance
  12-62. Commanders create an assigned area for the unit conducting the reconnaissance. They place lateral
  boundaries on both sides of reconnoitered routes. These lateral boundaries are far enough out from these
  routes to allow reconnaissance of all terrain from which an enemy force could influence each reconnoitered
  route. They draw lines of departure with reference to battlefield locations where enemy contact is possible.
  Commanders generally place these lines of departure before and perpendicular to the reconnoitered routes.
  This allows adequate maneuver space for the unit conducting the reconnaissance to deploy into a movement
  formation. These lines of departure create the rear boundary of the assigned area occupied by the units
  conducting the route reconnaissance. Commanders place LOAs far enough beyond the RP for each examined
  route, including any terrain from which an enemy force could influence that route. Together a SP and an
  associated release point define a reconnoitered route. Commanders require detailed information on these
  routes and may add phase lines and checkpoints to coordinate reconnaissance, control movement, or
  designate critical points. They place additional control measures on terrain features identifiable from the
  ground and the air to coordinate indirect and direct fires and assist in air to ground coordination. Figure 12-3
  depicts control measures associated with performing a route reconnaissance.
  Figure 12-3. Example of route reconnaissance control measures