曝光台 注意防骗
网曝天猫店富美金盛家居专营店坑蒙拐骗欺诈消费者
Imagine, how the landing might have occurred not knowing the surface wind was different from that of the flight path. Perhaps a less considerate pilot would plan on landing in the
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Figure 8-4. The step-down approach.
beets, believing the crop would not be hurt and the farmer would not care. Unfortunately, the balloon turns unexpectedly toward the power lines, causing the pilot to make several burns of undetermined amount, setting up a climb that prevents the pilot from landing on the dirt road. The road is directly in line with the balloon’s track but disappearing behind the balloon. Another good landing site becomes unusable because of the lack of planning.
The prudent pilot makes a nice landing on a dirt road with 25 percent fuel remaining, while the unprepared pilot dives, turns, climbs, and is now back at 600 feet in the air looking for another landing site. For the next attempt, the pilot has less fuel and is under more pressure, all because of not noticing the power lines to the left and not checking the wind on the ground before making the descent. Step-Down Approach
The step-down approach method involves varying descent rates. This procedure is used to determine lower level wind velocities and directions so that options may be considered until beginning the final descent phase to landing. There are other methods to evaluate lower level wind conditions, such as dropping strips of paper, small balloons, etc. While the descent path can be varied and sometimes quite shallow, it is important to avoid long, level flight segments below minimum safe altitudes without intending to land. Level flight at low altitudes could lead an observer to believe that the pilot has discontinued the approach and established level flight at less than a minimum safe altitude. [Figure 8-4]Low Approach
The second type of approach is a low or shallow approach. If there are no obstacles between the balloon and the proposed landing site, a low or shallow approach allows a pilot to check the wind closer to the surface. The closer the balloon is to the surface, the easier it is to land. Low approaches are suitable in open areas with a wide field of view and few obstacles.Obstacles and Approach Angles
Most good landing areas are not very large and generally have obstacles somewhere close by. The classic approach requires the balloon pilot to fly the balloon at a descent angle that clears the highest obstacle in its path to the intended landing site. However, if the pilot allows the balloon to descend below that angle, a rapid adjustment of that angle is necessary to avoid the top of the obstacle. In many cases, the attempt to miss an obstacle by a close margin may result in a period of overcontrolling or excessive burns and vents.
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A
B
Figure 8-5. In this approach, the pilot has elected to clear the obstacle at a minimal distance. Any overcontrol after Point A is likely to send the balloon past the intended landing area, and a very close clearance will be necessary over the obstacle at Point B in order to preserve the desired approach angle.
Figure 8-6. This approach is virtually the same as the one in Figure 8-5, but with subtle differences. In this case, the pilot has aimed for a location above the obstacle at Point B with appropriate obstacle clearance. Minor deviations after Point A on the approach path, if compensated for, still allow the pilot to make the intended landing area.
A
B
The inexperienced pilot usually misses the intended landing site and is forced to find another or has an undesirably hard landing, if the pilot manages to make the landing site. See Figure 8-5 for an illustration of this effect.
This type of approach is helpful by keeping the intended landing area in focus so that the descent results in the balloon touching down precisely where intended. Benefits to this methodology are straight line control and immediate visual feedback from the landing site. The disadvantage of using this specific methodology is that, again, any deviation from the depicted flight path may result in overcontrol or, at best, a “close shave” over the obstacle at Point B to preserve the approach.
Figure 8-6 illustrates the same vertical profile but with a few subtle and important differences. The initial approach is identical, but the initial target is different. Rather than focusing on the landing site past the barn requiring a clearance of two or three feet, this pilot has elected to “aim” for a point of safe obstacle clearance of the barn (about ten feet above the silo), knowing that a short vent on the other side “sharpens” the descent. It is clear that the balloon drops into the landing site somewhat closer to the obstacle, the conscientious pilot having already evaluated that possibility prior to committing to the landing. This methodology minimizes the possibility of overcontrolling and dramatically increases the chances of a successful landing.
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Figure 8-7. A good landing is something to watch.
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Balloon Flying Handbook(97)
