Althoughplottingcanbecontinuedaslongasthepibalremainsin  sight, only the three points marked will be used for this exercise.  Figure 3-9  illustrates the results of the above sequence. 300° 310° 330° True track at 450 feet your location A D B C Figure 3-1D. Plotting your course. $_{Figure 3-9.}$  A line drawn through the last two plots provides a basis  to measure the angle and determine the wind at that altitude. In  this case, it is 450 feet. To determine the wind directions at different altitudes, extend  lines between the plotted points as shown in  Figure 3-9  back  through the initial azimuth. Using the plotter, measure the  angle between the lines (the angle between the A-B line  and the C-D line). That angle, added to the original azimuth  heading, gives a good approximation of the winds at that  altitude. For the example shown in this sequence, the true  track at 450 feet AGL is 005°. A grid appropriate for this  computation is located in Appendix B. This exercise demonstrates a practical method for determining  approximate wind directions using items readily available  to most pilots. It does not require expensive handheld  calculators, laptop computers, or a theolodite that costs  thousands of dollars. There is some error inherent in this  process that can be lessened with experience and practice,  but the readings obtained by this method can offer real  time, on site weather data no forecast or briefer can provide.  [Figures 3-10  and  3-11]  The information on basic surface winds and winds aloft  readings gathered by this method can be used by a pilot  to project a flight path and anticipated landing sites with  a sectional or topographic map. This plot will form a “V,”  with the cone beginning at the launch site. The two legs will  represent the extremes of the plotted measurements. The  difference between these two extremes is called steerage.  Flying higher will track the flight path closer to the winds  The balloon pilot, more than pilots who fly other types of  aircraft, must have the capability of visualizing the winds  aloft in three dimensions. Continued spatial awareness  (how the balloon is moving through the air), is important  for maintaining control of the balloon and navigating to the  desired point on the ground. Every other safety measure  taken is compromised by inflating a balloon and taking off  without proper planning and an understanding of the winds  and terrain to be navigated.  [Figure 3-12] 3-7 aloft reading, while contour flying will put the balloon closer  to the ground track leg. Varying altitude will allow the pilot  to fly down the middle of the “v.” Accuracy will depend  on the consistency of the conditions, but flight paths and  landing sites may be predicted, after practice, with a high  degree of reliability. $_{Figure 3-10.}$  Practice pibal plots. These exercises are designed to  assist the student pilot in devleoping proficiency in using the pibal  plotting method. (answers on next page)