05-B: Ground Reference Maneuvers

Knowledge

K1: Purpose of ground refernece maneuvers

K2: effects of wind on ground track and relation to a ground reference

• Rectangular course
  • purpose
    • represents an airport pattern
  • analysis (naming does not correspond to airport pattern but to wind direction)
    • crosswind legs require crab into the wind
    • angles
      • small angles when turning from or into headwind leg
      • large angles when turning form or into downwind leg
  • Figure 62 (rectangular course)
    • turned more than 90°:
      • corner 2 and 3
    • turned less than 90°:
      • corner 4 and 1

• S-turns

  • requirements
    • 600 to 1000 feet AGL
  • analysis
    • slowest groundspeed during the line crossing with headwind
    • fastest gorundspeed during the line crossing with tailwind
    • greatest grab during the crosswind points

  • Technique 1:

    • textbook
      • Downwind w/ tailwind
        • Steep
        • Medium
        • Shallow
      • Headwind
        • Shallow
        • Medium
        • Steep
    • mnemonic:
      • as you start a semi-circle: ask yourself "am i fast or slow"
        • fly fast (tailwind) -> fast bank start (steep)
        • fly slow (headwind) -> slow bank start (shallow)
      • based on the start speed (steep or shallow), complete to the inverse (steep -> medium -> shallow or shallow -> medium -> steep)
    • failure results
      • falsely starting or staying shallow widens the circle diameter
      • falsely starting or staying steep narrows the circle diameter

  • Technique 2:

    • stretch the S into the wind
  • Technique 3:
    • pick fly-over points
  • Figure 66 (S-Turn Diagram)
    • understand:
      • 1:
  • Turns around a point

K3: Effects of bank angle and groundspeed on rate and radius of turn

Ground reference maneuver with wind corrections: S-turns

if ground speed < airspeed: headwind (e.g., groundspeed 0, airspeed 100 knots) if ground speed > airspeed: tailwind (e.g., groundspeed 100, airspeed 200)

1) clear by vision 2) clear by turn 3) reference line 4) perform constant-radius turn - for the headwind semi-circle: shallow, medium, steep - for the tailwind semi-circle: steep, medium, shallow

Ground reference maneuver: Turns around a point

Ground reference maneuver: Rectangular course