text: Landing Plan
  Itreducesflexibilitybecause forcesaredispersed.
  (cid:132)
  (cid:122) Adjacent dropareas. Landingbattalionsonadjacent areas withina single large ABNIBCT drop
  zone has, although to a lesser degree, the same advantages and disadvantages of dropping on
  separatedropzones.
  TIME OF DELIVERY
  5-33. No set rule can be prescribed for the timing of an airborne operation. It varies with each situation;
  however, the airborne force tries to conduct airborne assaults during limited visibility to protect the force
  and to surprise the enemy. The commander sets the specific time of delivery. However, for the landing
  plan,timesarestated interms ofP-hour.P-houristhe specific houronD-day at which a parachuteassault
  commences with the exit of the first Soldier from an aircraft over a designated drop zone. P-hour may or
  maynotcoincidewithH-hour(FM6-0).Thefollowingconsiderationsaffectthetimingoftheoperation.
  SUPPORTOFTHEDECISIVEOPERATION
  5-34. Theairborneassaultcanbea shapingoperation.Ifso,thetimeof commitmentoftheairborneforces
  in relation to the decisive operation is directed by orders from higher headquarters. It is determined in
  advance according to the mission, the situation, and the terrain. For example, the airborne force can be
  committed in advance of the decisive operation to give the airborne assault an increased element of
  surprise. It can be committed during the decisive operation to neutralize specific areas or to block the
  movementofenemyreserves.Itcanbecommittedafterthe decisiveoperationtoassistabreakthroughorto
  blockanenemywithdrawal.
  VISIBILITY
  5-35. Thedecisionasto whetherthe airborneforceis committed bynightordaydependsontheestimated
  degreeofairsuperiority,theneedfor security fromenemyground observation,therelativeadvantage tobe
  gainedbysurprise,andtheexperienceofbothairliftandairbornepersonnel.
  5-36. As an advantage, night airborne operations greatly increase the chance of surprise and survivability,
  and reduce the chance of attack by enemy aircraft during the air movement. They reduce vulnerability to
  antiaircraft fire, conceal preparations for takeoff from the enemy, and reduce the effectiveness of the
  defender’s fires. Daylight operations provide better visibility from the air and ground, more accurate
  delivery,quickerassembly,andmoreeffectivefriendlyfiresthannightoperations.
  5-37. As a disadvantage, night airborne operations in zero visibility require well-trained Soldiers and
  aircrewstolocatethe dropzoneandassemblerapidly. Theyprovidemore airand landnavigationproblems
  and offer slower rates of assemblythan day operations. Night operations reduce the effectiveness of close
  air support. Day operations increase vulnerability to enemy air defense, ground fires, and air attack, and
  theyresultinlossofsurprise.
  INTERVALS
  5-38. The time interval between delivery of the assault echelon (P-hour) and the follow-on echelon
  dependsontheavailabilityof aircraft,the capacityofdepartureairfields, the numberofaircraft sorties that
  can be flown on the initial airborne assault, the availability of drop zones or landing zones within the
  objective area, and the enemy situation. For example; if there are unlimited aircraft, ample departure
  airfields, numerous drop zones or landing zones within the objective area, and little or no enemy air
  defense, the commander could deliver the follow-on echelon immediately after the assault echelon. Thus,
  the time interval could be so brief that it would be hard to determine which was the last aircraft of the
  assault echelonand whichwasthefirst aircraftofthefollow-onechelon.Regardlessofthe timingselected,
  avoidsettingapattern.
  SECTION III – PREPARATION AND SUPPORTING FIRES
  5-39. An ABNAF’s organic fire support is typically limited to its mortars when initially conducting the
  airborneassaultphaseofanentryoperation.TheABNAFCmust planfor theuseoffiresupportexternalto