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As previously discussed, a weather brief must be obtained prior to flight; as a procedural matter, the information from the briefing sets the parameters for the flight (launch site, flight track, and potential landing areas).
All electronic sites and briefings represent the starting point for how weather affects the flight. A balloon pilot should not make the mistake of gathering weather data, getting a forecast, deciding to fly, and then paying less attention to actual weather cues. Weather monitoring is an ongoing process that starts on the drive to the launch field and continues until the balloon is packed after landing. Continue gathering weather data for the flight until safely back on the ground.
Despite using the most current and complete electronic weather data available to consider before driving out for the flight, each pilot must never lose sight of the fact that hot air balloons are visual flight rules (VFR) aircraft. Many pilots lose all access to unlimited or even selected electronic weather information en route to or at the launch site. Unless the launch site is a reporting station for any weather service, a pilot is required to visually interpret and evaluate weather data specific to the launch site. Local surface conditions—particularly winds below 500'–800'—show the greatest variability of both speed and direction. These winds are perhaps of greatest importance in determining the conditions and risks for launch and landing. A number of simple observations enable the balloon pilot to gather this data at the launch site, as well as during the flight. [Figure 6-2]
The balloon can sometimes provide valuable weather information provided the pilot knows what to look for. Fabrics on a laid-out envelope begin rippling around eight miles per hour (mph), while 10–12 mph sends small bubbles of air past a closed throat and up along the load tapes. Such information, perhaps unavailable or inaccurate elsewhere, can prove invaluable, especially during the initial phase of flight.
Each pilot must sharpen his or her ability to read and interpret local surface conditions for one primary reason: up to 1 hour may elapse between gathering weather data online and laying out at the launch site. Weather patterns can change in far less time than this, and local conditions can change almost instantly.
Some pilots choose to rely on a portable weather station or handheld wind meter to monitor local conditions at the launch site. Cost, size, portability, and features vary among brands, but each can provide useful information on wind speed/direction, maximum gusts, and other weather data. These can range from a small $100 handheld wind meter to a $500 weather station with 15" mast and dashboard data display. [Figure 6-3]
Perhaps the cheapest yet most valuable launch site weather aid is the pibal or pilot balloon, a 10–14" helium-filled balloon released at the launch site for visual weather cues and forecast confirmation. Some pibal actions clearly mean cancel the flight: rolling along the ground, not clearing obstacles, climbing then diving, or dramatic speed/direction changes (which indicate wind shears). To read and confirm winds at different altitudes, release several pibals at 10–20 second intervals. Fill the first with 100 percent helium, the second with mostly helium and a breath of air from your mouth, and the third with helium and two breaths. This creates different rates of ascent which helps gain a better perspective of the low level winds. Every pilot benefits from having pibals in their vehicle and using them before launch. Appendix D lists various rates of climb for different sizes of pibals; using this knowledge, the pilot can determine the altitudes at which the winds change.
6-4
Every pilot and crewmember can build a mental database of visual cues that report weather data. More important than pre-launch weather is inflight weather, which is further removed in time from forecast conditions (electronic or briefings) but can change just as fast and dramatically. Wind speed or direction changes can signal developing rain or frontal movement. Radar returns require human interpretation and can miss developing conditions or provide false echoes off birds or buildings. Weather-savvy pilots and crew gather weather information from whatever source is available to them anywhere, at any time.Performance Planning/Fuel Planning
The good balloon pilot checks the balloon’s performance charts, considering that day’s conditions, and comes to a reasonable conclusion regarding the limitations of the balloon for that particular flight. Prior to flight (and perhaps even prior to layout), fuel gauges should be checked to ensure there is sufficient fuel on board to conduct the planned flight.
The Chase Crew
Generally, there are two different areas of responsibility for a crew: inflation/launch and chase/recovery. Both are usually referred to as ground crew. Passengers often serve as inflation crew, become passengers for the flight, and crew again after the balloon has landed. Before the noise and activity make discussion difficult, the pilot should give the crew briefing and discuss any requirements before inflation.
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Balloon Flying Handbook(73)