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Ideally, the launch site should be a large, open grassy area. Obstacles in the flight path are a consideration. As a general rule, the balloon should be placed as far as possible upwind of any obstructions to flight (powerlines, trees, buildings, etc.), using a minimum of 100 feet of clearance for each knot of wind. [Figure 6-7]
6-7
Figure 6-7. Examples of good (top) and poor (bottom) launch sites. In the top picture, the pilot would have adequate clearance above the power lines at the far end of the field, as well as more than adequate area to layout the envelope. In the bottom picture, the pilot would have a very short area to lay out. There are obvious obstacles, such as the trees and cell phone tower, which create hazards to a safe launch.
6-8
Figure 6-8. Unloading the basket and moving the vehicle forward minimizes equipment carrying.Landing Sites
The best launch site is of little use if there are no appropriate landing sites downwind. Many pilots examine their flight path from the perspective of the landing area, particularly in an area of few landing fields, and “reverse plan” their launch site in order to make the appropriate choice of launch sites. Occassionally, this may require using a launch site that may be somewhat less than desirable. As long as the launch can be made safely, with appropriate obstacle clearance, this is perfectly acceptable. Launch Site Surface
After determining the flight direction, the next condition that determines the details of the balloon layout is the actual launch site surface. Of course, all pilots want to lay out their balloon on clean, dry, short, green grass. Most pilots are not that fortunate unless they have their own launch site and never fly from different places. Wise pilots modify their techniques according to available conditions, or they have more than one layout procedure to adapt to various launch sites.
Whether flying from a regular launch site, a brand new location, or from an assigned square at a rally, check the ground for items that may damage or soil the balloon. Look for and remove nails, sharp rocks, twigs, branches, and other foreign objects. If there are patches of oil or other substances, cover them with pieces of carpet, floor mats from the chase vehicle, tarps, or the envelope bag. Some pilots cover the ground where they lay out their balloon with a large tarp every time they fly.
Unless flying at a known site, do not assume it is all right to drive the chase vehicle directly onto the launch area. There are some locations (a soft athletic field, for example) where it is necessary to carry the balloon onto the launch area. If using private property, it is necessary to get permission to use the property for flight activities. This may be the first experience with landowner relations, and the considerate pilot takes action to minimize his or her impact on the landowner’s property. Landowner relations are an important part of ballooning, and are discussed in greater detail later in this chapter.Balloon Placement and Wind Direction
Consider the wind direction before the balloon is unloaded from the chase vehicle. Take into account the surface wind at the time of cold inflation to avoid carrying a heavy balloon bag and basket around. A “Murphy’s Law” type of rule is that the wind always changes during inflation. Local knowledge is invaluable. If other balloons are around, check with the most experienced local pilot.
A wind change at or shortly after sunrise is normal in many places. If the balloon is laid out prior to sunrise, a wind change is likely. If flying in a new area, it is beneficial to watch the local pilots, as they have knowledge of local conditions and idiosyncrasies. Some general trends are that air usually flows downhill or down valley first thing in the morning, and air usually flows from cold to warm in the morning. The air drainage may stop very shortly after the sun rises and starts heating the ground. The early morning wind may come from a different direction than the prevailing or predicted wind. Some local pilots may lay their balloons out in a direction that does not match the airflow at the time, but that corrects 15 to 30 minutes later when the sunrise change occurs and the inflation starts.
Removing the Balloon from the Vehicle
Once the specific location on the launch field has been determined, the balloon should be removed from the vehicle, or unloaded from its trailer, and prepared for flight. [Figure 6-8] Good procedures and habit patterns formed here minimize the amount of lifting of balloon components, and reduces the wear and tear on the crew and the pilot, as well as the equipment itself. Despite being a lighter-than-air aircraft, the packed balloon and basket are heavy; the average sport balloon system can weigh over 550 pounds.
One method is for the pilot to establish the specific location and direction of layout, and direct that the basket be placed there. The transport vehicle maneuvers to allow the basket to be removed and placed at the pilot’s discretion, and then pulls forward about 15 or 20 feet to allow for the envelope bag and inflator fan to be removed and placed on the ground. The vehicle may then be removed from the launch site, or moved
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Balloon Flying Handbook(76)