text: Chapter 6
  RANDOM APPROACH DROP ZONE
  6-129. A random approach DZ is a variation of a previously surveyed DZ. It must be big enough for
  multiple run-in headings. Any axis of approach may be used as long as the resulting DZ meets the
  minimum criteria for the load or personnel being airdropped, and as long as it is within the boundaries of
  the original, surveyed DZ. In all cases, the DZSTL performs a safety-of-flight review before using a
  random approach DZ.
  AREA DROP ZONE
  6-130. An area DZ (Figure 6-18) has a start point (A), an endpoint (B), and a prearranged flight path
  (line-of-flight) over a series of acceptable drop sites between A and B. The distance between A and B is no
  more than 15 nautical miles. Changes in ground elevation within one-half NM of centerline should be no
  more than 300 feet. The reception committee can receive the drop anywhere between A and B within
  one-half NM of centerline. Once the pilot identifies and locates the prebriefed signal or electronic
  NAVAID, he can make the drop.
  Note: Area DZs only apply to C-17 operations when crews are SOLL II qualified.
  Figure 6-18. Area drop zone.
  CIRCULAR DROP ZONE
  6-131. The size of the DZ is governed by mission requirements and usable terrain. The PI of a circular
  DZ is normally at the DZ center to allow for multiple run-in headings. For specific missions, the PI
  location may be adjusted to allow for dropping loads such as sequential heavy equipment (HE) loads or
  mass container delivery system (CDS) loads on circular DZs. However, this limits the run-in heading to
  only one direction. In all cases, the minimum DZ dimensions for the type and number of loads being
  dropped must fit within the surveyed circular DZ. The DSZTL computes the circular drop zone as shown
  in Figure 6-19 to determine whether the minimum DZ fits into the surveyed circular DZ. When the PI has
  been relocated, he should use Option 2. The DZSTL calculates and records the size of the circular DZ
  using Option 1 on the DZ survey form. This prevents confusion and reduces the risk of off-DZ drops if the
  circle center point is used as the PI.