text: Chapter 4
  y Field elevation.
  y Landing formation.
  y Terrain conditions.
  y Traffic situation.
  y Obstacles.
  y Availability of visual signals (smoke, light gun, and so forth).
  y Next reporting point.
  Figure 4-16. Terrain flight modes.
  4-52. Before reaching the CCP, IAW instructions from the flight leader, all helicopters in a flight switch
  to the pathfinder control frequency.
  Note: Pathfinders must stay prepared to provide ATC and navigational aid to all aircraft in and
  around the landing site in case those aircraft have no specified flight plan.
  4-53. The helicopter formation continues along the flight route to the RP. The electronic and visual aids
  at the RP (if manned) help pilots navigate. As each helicopter passes over or near the RP, its flight serial
  leader reports this to the respective landing site CC. Then the helicopter flies directly to the assigned
  landing site. The CC at the individual landing site uses visual signals, steering commands, or electronic
  homing techniques to help any flight that cannot find its landing site.
  Day Operation Signals
  4-54. For daylight operations, you can use different smoke colors for each landing site. You can use the
  same color more than once, just spread them out. Use smoke only if you have to, because the enemy can
  see it, too. Try to use it only when the pilot asks for help locating his helicopter site.
  Night Operation Signals
  4-55. For night operations, IR strobe or other visual signals in lieu of smoke. As in daylight, red signals
  mean "DO NOT LAND," but you can also use them to indicate other emergency conditions. All concerned
  must plan and know emergency codes. Each flight lands at the assigned site according to CC messages and