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3-4-05
Dear Family and Friends,
I am exploring a new medium that I call the illustrated story. Look it over and tell me what you think.



In my younger days, I became addicted to flying, and even went as far as to own three different aircraft. What a glorious addiction! But one of the cold, hard, facts of life is that planes and kids don't grow out of the same wallet. So, with the help of a loving wife (whose many talents included the ability to "save" money by spending it) and the demands of two wonderful but costly children (whose only cognizant use for currency was to explore it's mouth feel), I was able subdue those cravings (or at least the outward manifestations thereof) and sold my magic carpet. Another of the cold, hard, facts of life is that addictions rarely "go away," and it appears that mine has resurfaced in a slightly different guise. I have taken up flying... kites.
As a child, I was exposed to several small, unstable, inexpensive devices that gyrated drunkenly across the sky, rarely stayed aloft more than a few minutes, and had an inexplicable affinity for trees, power lines, and other inaccessible locations. Then, some 6 years ago, when walking through Sam's Club, I happened upon a kite display that was being closed out. Thinking that my children might enjoy playing with one for a few moments before trashing it, I indulged in what economists refer to as an impulse purchase (for me, a fairly uncommon occurrence). It was at least a year between the purchase and the first flight of this kite (ominously enough in the shape of an aircraft). But when it first flew, and proved to be a stable aerial platform, the old addiction began to emerge. The twine supplied with the kite was modest in length, and so I tried one slightly longer. One string led to another, and it was soon evident that I was in need of some serious accoutrement upgrades.

The reel supplied with the kite deformed under the pressure of bringing the kite in, even when the wind was relatively light, so I constructed an upgraded version using PVC pipe. This was one of those really good ideas that just don't work. Under pressure of the string, the device defromed to the point that the two ends of the "H" almost touched each other. It also came apart while fully loaded with twine (not terribly surprising given that I ingnored AJ's advice to glue it).
After untangling the 735 yards of line, I designed and built model H2 (left) that was basically the same thing made out of metal. Unfortunately, it also deformed under pressure and, given the placement of the handles, "wobbled" while reeling in twine. This caused the twine to be wound from corner to corner until the pile collasped under its own weight, allowing the string again became a tangled mess.
The next try was model O1 (below). This was an ingenious attempt, but proved unwieldy and held too little twine.
At this point, Sam's Club re-entered the scene with their seasonal kite display, and I bought a second one (billed as a three dimensional box structure) that measured 82 inches at its widest point, and had 20 foot streamers on each wingtip. Its primary design consideration was to produce lift, and visual effects were limited to color schemes. After this kite blew away (in a relatively stout wind, on about 600 yards of 12 pound test monofilament fishing line) never to be seen again, I went to masons twine (touted as having a test strength of 150 pounds). About this time, I set the goal of getting a kite out on a mile of line, and H2 simply would not hold that quantity. Further, one of the jagged ends snagged the line one too many times, and two (of three kites on the same line) blew away. Fortunately, we were able to recover them, but clearly some system improvements were needed.
Enter H3 (left), basically a reinforced, three-dimensional reconstruct of H2, which boasted a central handle with a freely turning sleeve. This device released string smoothly, but rewinding long distances quickly became a chore, particularly if there was even a modest wind. At about this point, it became evident that long distance kite flying was a team sport. That is, the device storing the string cannot be used to pull it in. Instead, one person pulls the string in, and another winds it on the reel.
This conceptual breakthrough resulted in model O2 (right). This reel collects and stores the line, but lacks the strength (and leverage) to bring the kite down. I calculated that construction of the prototype would take about four hours, but with a couple of design (and re-design) changes, it occupied all my free time for the better part of a three-day weekend. I loaded it with all the 1.1 mm twine I possess (calculated at 1801 yards), and I estimate that it has a capacity to hold somewhere between 4 and 5 miles. It is a stand-alone model that can be staked to the ground. As is my wont, I fabricated it out of "stock" on hand (a bicycle wheel, head bolts [and washers] from of the Colt, pieces of an ancient swing set [that was on the property when we moved here], heavy galvanized wire [think hot dog roasters], and some quarter inch pipe we "borrowed" from Storm Cocks twenty some years ago). AJ insisted on helping with the welding. Some of it he did quite well, and other parts I revisited. Welding wire to wire is not trivial for someone just learning to melt metals (or for experienced welders either, if the truth be known). As it neared completion, it became obvious it would not fit in my vehicle, so I pressed a recently acquired bicycle rack into service.
All my ideas are good ones (even the bad ones that don't work) but in this particular contraption, the string guides were the coup de grâce. They mandate that the string is laid down in the center of the reel, and keep it from becoming entangled in the stabilizating super structure. They also provide just the right amount of friction to produce the proper tension in the wound string. Though it is an ugly monster, this reel will store string faster than three men and pull it in. So... with these improvements in place, we were ready for the record setting attempt.
The attempt occurred last weekend. Sabrina and her husband Braxton Herring came out from Tucson, and AJ and I comprised the remainder of the team. About 2:30 in the afternoon, the perfect combination of wind, temperature, lack of precipitation, and cloud cover all came together, and we launched. I was the stupidvisor, AJ and Sabrina handled the kite lines, and Braxton functioned as photographer (thank him for these photos).
We ran the first kite out about 425 yards before tying the second kite to the line. The shallow angle of attach of the kite flying on a short line suggests that most of the energy of the wind was translated into lift, and little into drag. Still, the string has a width of 1.1 mm, and 1760 yards of it hanging in the sky has an area of greater than two square meters. We estimated that there was 10 to 15 pounds of pull on the string with it fully extended, and I suspect that most of that drag comes from the string.
With all the string extended, we measured the angle at 25 degrees above the horizon. Assuming first that my command of trigonometry is still functional and second that the string is straight (which it is not) the kite was 820 yards (or 2460 feet) above our heads. In reality, it probably reached an altitude of around 2000 feet.



Some of my children don't understand that works of art take time, and I'm catching flack for not having this event open to the public. I guess the thing to do is to stop promulgating my esoteric cogitations and post the rest as random images. They are basically self-explanatory anyway.

This telephoto shot (right) records the record. The three kites are on the same line. The top one is tied to the end of the string (735 yards measured plus four rolls of 800 feet each, which I calculate at 1801 yards total), the second one is about 420 yards from the first, and the last one is about 480 yards from the second. When the kites are at that distance, there really isn't much to look at, but the pull on the line makes you think that maybe you snagged a flock of vultures. It only required three kites to reach a mile, and I have a total of five (plus the afore mentioned airplane kite). Maybe next we should try for twice that distance?


Well, that is a brief look at how I have been spending my free time as of late. Alan.
Post Script: If you are interested, NASA gives the formula describing the shape of the kite string as:

Y=-(D/p)+cosh(arcsinh(((L-g-W)/D))) + (D/p)cosh((p/D)X+(arcsinh(((L-g-W)/D)))

where:
D = drag
p = unit line weight
L = lift due to kite
g = total line weight
W = kite weight


Assuming :
D = 7.7 lbs
p = .00255114 lbs/yard
L = 7.0 lbs
g = 4.490006 lbs
W = 2.2 lbs
the graph to the right shows the shape of the string.
Based on my memory, that may even be correct.

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