text: Mobility
  Execution
  18-38. Execution involves monitoring the situation, assessing the mission, and adjusting the order as
  needed. When the situation deviates from the order, commanders direct adjustments to exploit opportunities
  and counter threats. Adjustments that may be necessary during breaching might include—
  * Allocating additional assets to the support, breach, or assault force due to attrition.
  * Changing the location of the POB or point of penetration.
  * Modifying the scheme of movement and maneuver and changing the order of the units passing
  through the created lane.
  18-39. For breaching, the commander focuses on monitoring, assessing, and adjusting the critical events of
  a breach that were rehearsed. The critical events that are generally associated with a breach are—
  * Occupying support by fire positions.
  * Suppressing the far side objective.
  * Employing obscuration.
  * Reducing the obstacle.
  * Assaulting the far side objective.
  * Consolidating on the far side objective.
  * Passage of follow-on forces.
  GAP CROSSING
  18-40. A gap is a ravine, mountain pass, river, or other terrain feature that presents an obstacle that may be
  bridged (ATP 3-90.4/MCTP 3-34A). Gap crossing in support of maneuver is similar to a breach in that the
  force is vulnerable while moving through a lane or across a gap. Maneuver units are forced to break
  movement formations, concentrate within lanes or at crossing points, and reform on the far side before
  continuing to maneuver. While much of the terminology and planning associated with gap crossing is the
  same as that used in a breach, gap crossing and breach differ in scope. The amount and type of assets involved
  also differ. Combined arms breaching sometimes includes gap crossings as a reduction method. Since the
  primary focus of planning and preparation is on the breach, they are typically discussed as a subordinate part
  of the breach rather than as a separate gap crossing.
  18-41. Gaps will exist in the operational environment and present a significant challenge to movement and
  maneuver. A gap crossing is the projection of combat power across a linear obstacle (wet or dry gap) (ATP
  3-90.4/MCTP 3-34A). Historically, gap crossings were described only in the context of crossing rivers. A
  river crossing is a special type of gap crossing required before ground combat power can be projected and
  sustained across a water obstacle. A centrally planned and controlled offensive mission requires the allocation
  of specialized crossing resources and a force dedicated to the security of the bridgehead. While river crossing
  is still considered one of the most challenging of gap crossings, a river is only one type of gap that can
  obstruct freedom of mobility. The fundamentals of crossing any type of gap are essentially the same as those
  fundamentals that have been associated with river crossing. River crossings are simply one focused set of
  challenges among all of the possible types of gap crossings. A gap crossing encompasses wet or dry gaps in
  any type of environment or uses organic and augmenting engineer (and other) elements best suited to
  accomplish the mission.
  Types of Gap Crossing
  18-42. The gap crossing types are―
  * Deliberate.
  * Hasty.
  * Covert.
  18-43. Each gap crossing type has a general list of conditions that help define the category. The planning
  requirements for each type of gap crossing are similar. However, the required degree of detail and necessary
  conditions for a high degree of success will vary based on the type and the unique features associated with a
  crossing mission. In all cases, the ability to conduct any type of crossing begins by providing a crossing force