text: Drop Zones
  Flanker Panel
  6-102. Place the flanker panel 150 meters to the left of the alignment panel, as seen from the drop
  heading. Orient the long axis of the panel so it is perpendicular (90 degrees) from drop heading, and
  parallel to the alignment panel.
  LIGHTS
  6-103. At night, replace panels with lights (use one light for each panel). Do not use chem-lights for DZ
  markings. For operations requiring security, night DZ markings should be visible only from the direction
  of the aircraft’s approach. If flashlights are used, they should be equipped with simple hoods or shields and
  aimed toward the approaching aircraft. Omnidirectional lights, fires, or improvised flares may be screened
  on three sides or placed in pits with the sides sloping toward the direction of approach. Use directional
  lights for the approach, corner, alignment, and flanker. If necessary, you can use the directional light holes
  for the far code letter and line up the base light with the corner light. Figure 6-10, page 6-36, provides
  construction requirements for Army code letters. Mark the release point with some type of identifiable light
  source to distinguish it from all other DZ markings.