Last month in Part 1, author Jim Isler introduced the concept of Appropriate
Aerostatic Meditation-a preflight checklist item. A checklist helps insure that those
things essential to launch and flight have been done. There are two reasons why this
meditation should be on the checklist: first, aviation permits of few errors; and second,
introducing a new element, meditation, risks being forgotten if you don’t check having
done it. The idea is to do certain things which will make you aware of the morning, and
better prepared to anticipate what will happen to you and your balloon.
Micrometeorology is the knowledge of both small effects, and local effects. It studies
the airflow in a small area, driven by predictable interaction of the three cosmic forces:
the sun, the topography, and the air itself.
All forms of aviation are influenced by geographic features and by the weather.
Isler’s thesis is that weather is less relevant to the balloonist. Weather tells us whether
or not to get out of bed. A different set of phenomena govern our actual flight. They are
the interaction of place, time of day, and what the locals call weather. Given that we
only go out on what most people would call good days, our microscope must look
differently at weather than most aviators.
After the decision is made to go, the most important published weather data
governing our flight becomes the variety of atmospheric pressure readings distributed
around our weather country, that area within 25 to 50 miles of the launch site.
Last month the author utilized the interaction of the three cosmic forces near
Larkspur, Colorado to demonstrate his theory. Below he takes a brief look at the
Albuquerque box and the factors influencing it. On the opposite page are "how to"
instructions on the art of meditation. Editor.
Let’s look at Albuquerque, just the opposite situation from Larkspur, Colorado that we examined last month. (Figure 1) The mountains are on the east, with the land gently sloping upward to the west. The mountains to the east, the Sandias, by blocking the sun, slow the warming of the "valley". The "West Mesa", as they call the high desert west of town, actually begins heating up much earlier than the Fiesta launch site. ABQ has a feature seldom encountered in ballooning called "the box". Low level drainage is predictably down the river to the south, but the higher level air, almost always encountered between 500-1000 feet, is usually running north. It is also unusually calm in ABQ, so both effects, at least at Fiesta time in October, are low speed affairs.
In profile, (Figure 2) you can see that the sun gets to the mesa much more quickly than the valley, but the gentler slope of the West Mesa, compared to the eastern slope of Colorado, makes the effect on drainage less dramatic. Here again, the rising air over the mesa, heated earlier than the same strata over the valley, pulls the balloons west of the box. Early on, we float out of the launch field downriver; rising, the early balloons tend north along the river. Higher and later balloons, on a day where everything doesn’t die early to dead calm, are pulled west across the river. The really high flyers, of course, tend east on the "real" wind.
Now here is where Zen comes in. By meditating on the topography, global weather, local solar activity, and the temperature change expected, we can rule the world-or at least predict the flight and win the competition.
Face the rising, (or setting) sun: What time is it, in relation to sunrise, or sunset? It is becoming the custom at one of our launch sites to arrive half an hour after official sunrise, because we know the drainage doesn’t settle down until an hour after. How strong will the sun be today? He is farther south in the winter than in the summer. If it has been a very cool night he will have more work to do. What will be the effect of clouds on solar heating?
Turn upwind. Feel the force of the drainage (making sure it is not the wind from your fan). Remember that we’re talking 2-5 mph here. If it is a windy inflation, the drainage will be overpowered by weather. Even then, it will have an influence. How strong is the drainage? Is it drainage or weather you are feeling? Freshening or weakening? Usually drainage will slow with the sun’s rising, then the real wind of the day shows up. Is it going to be a changeable day? Here’s where you integrate your official FSS weather briefing data.
Turn downwind, looking down the drain. Does it get shallower or steeper, broader or narrower? Will you speed up or slow down if you climb out slowly? What is down there? If it is a three-mile downward-sloping river valley, the effect will be different from hilly country or a prairie. What will the rising sun do? Predict the effect on today’s drainage.
Turn downwind, this time as referenced by where you expect to land. It is entirely possible that it is the same direction as your layout. Now, think about your climbout options: low and slow in the flow; pop up to escape it; something in between? What will the early thermal effect be? Then think about where you’ll be an hour from now. What are the characteristics of that place? Will there be drainage there? Sometimes when we think the wind will come up toward the end of our flight, we can have an alternate plan to change direction to more hospitable high wind landing sites.
Sometimes there is a fifth facing. If none of the first four were West, it is important to include a nod toward the direction most of America’s weather comes from. You are now facing away from whatever is creating your drainage. The eastern side of a drainage "valley" is particularly important. If the height of this wall is high enough, the sun will warm the western side later, but more quickly, bending the drainage to the west. If the upsun side is low, drainage will be erased earlier.
Most experienced pilots have observed all these things. What many experienced pilots do not do is to plan their flights for maximum control. Once in a while it is fun to just hang it out-launch and fly with no particular destination in mind. Airplane pilots sometimes take off and "bore holes in the sky", enjoying tossing their craft about and returning to do a few touch and goes. Popular conceptions hold that balloonists don’t know where they’re going, or when they’ll get there. How much fun it is to announce your flight plan early; showing pride when you make it, laughing at yourself when none of your plan comes together.
Local knowledge helps with the chase, and that’s what we often seek when we draft indigenous peoples out of the crowd to crew for us. If you have time, especially if you meet them the night before a flight, you can learn a lot besides "red areas" and roadblocks. Few non-balloonists will be able to explain local drainages, and most balloonists’ eyes will glaze over if you do not ask the questions properly.
For example, if you break out a road map, the creeks and hills may or may not be displayed. A topo map will often, but not always, display the roads. Only when the two are used in conjunction can local knowledge be tapped successfully. Try it the next time you go to a new Rally, or a place where you’ve flown only a little. First spend some time with a topo map, then talk topography with the locals using the road map! You show them where the creeks, rivers, and hills are. Remember that high ground is a hill. It doesn’t have to have the word "hill" or "Mount" to count. Don’t ask if the airflow is quick, or westerly-even balloonists may not have noticed, since we are talking 3-5 mph flow-ask if it is usually still in the mornings, or where does the wind usually come from hereabouts. Their answers will tell you what will probably happen on a good day as the drainage fades with the rising sun, even if it is counter to what you thought your topo map study indicated.
Remember that downstream in the morning is often upstream in the evenings. Albuquerque illustrates this. Morning flights at low altitudes are to the south. Evening flights reverse the trend almost exactly.
Nearly anyone can learn to fly a balloon. Nearly any craftsman can make a wall or draw a picture. But an artist can create a world. We can be artists in our sport. When we insert ourselves into the sky, we can fly and survive, or we can appreciate the marvel of our situation, work with the elements at a new level, and ascend to truly new heights.
Ed note: We recommend reading this article until you can hear the sound of one hand clapping! A small book, Mastery, by George Leonard, complements this article, and leads the committed pilot toward the promised delight.
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