text: Chapter 3
  TRAFFIC PATTERN LEGS
  3-28. The traffic pattern has five possible legs. The pathfinder does not use them all at once. The pilot
  must at least fly the final approach leg, regardless of the type of approach (Table 3-4).
  Leg Flight Course Direction
  UPWIND Parallel to land heading Landing direction
  CROSSWIND Right angle to land heading Landing direction
  DOWNWIND Parallel to land heading Direction opposite of landing direction
  BASE Right angle to landing runway Extends from downwind leg to intersection of
  runway centerline (extended)
  FINAL Along runway centerline Landing direction; extends from base leg down
  (APPROACH) to the runway
  Table 3-4. Traffic pattern legs.
  ADVISORY SERVICE
  3-29. The pathfinder controller issues advisories for the safe operation of aircraft in his area of
  responsibility. He might include such information as the temporary or permanent conditions on the
  landing field.
  3-30. Temporary conditions can include—
  y Construction work on or immediately next to the movement area.
  y Rough portions of the movement area.
  y Degraded runway braking conditions due to ice, snow, mud, slush, or water.
  y Parked aircraft on the movement area.
  3-31. Permanent conditions can include—
  y Excessive slope.
  y Obstacles 18 inches high, wide, or deep on the HLZ.
  y Elevation.
  3-32. No two landing areas and situations are the same. Each location presents its own problems with
  respect to environmental conditions, peculiar weather, preferred landing directions, and so forth.
  For example—
  y The final approach to a particular runway or HLZ might require a higher-than-normal glide
  slope angle.
  y Under certain wind conditions, unusual terrain features near the airfield or HLZ can cause
  turbulence. This could threaten nearby aircraft. Helicopters also can create turbulence that
  could result in harm to light aircraft.
  y Prohibited areas, trees, mountains, or other obstacles and hazards directly in line with the end
  of the runway or around the HLZ can require the pilot to turn or maneuver the aircraft abruptly
  right after takeoff (liftoff).
  y If friendly forces fire either artillery or mortars within the control zone, the pathfinder might
  need to tell the pilot the origin, range, direction, and maximum ordinate of the firing. He also
  tells the pilot about any air strikes in the control zone, especially those by high-performance
  aircraft. He also gives the pilot any available information about the enemy situation.