The Bonk Heard 'Round The Sod Farm

Sat, 15 Mar 2008 00:16:46 GMT

I don't believe I have ever blogged except obliquely about my long involvement with radio controlled model sailplanes. They were a passionate hobby for me until I had to stop flying because of the cost in time and money that conflicted with my commitment to give Annie the best care I could. I also lost contact with one of my two primary support groups of friends when I quit flying. I could not possibly have asked for a friendlier, more accepting group of people with whom to have become associated. Excluding the dentist from Detroit's flight crew, that is ... but that really is another ~~story~~ rant.

Model sailplanes are launched in several ways, but most have in common the central principle of something or someone pulling them into the sky like a kite. Once the model reaches the maximum altitude allowed by any of the methods or by the contest rules, it is released and flying on its own. The pilot on the ground then controls it via radio signals which are converted to mechanical movements of the model's control surfaces by tiny servo motors. Any model flier would tell you that this is a grossly simplified explanation, but I am assuming that you do not want a lecture on the Bernoulli effect's relationship to the creation of "lift" in a wing or the techniques used to build a wing from foam, fiberglass, kevlar and carbon fiber in a vacuum bag. I'm guessing that you want to know about the "bonk."

One of the simplest contest types in which we engaged involved keeping the model in the air for a specified amount of time (two minutes, four, six, 10, or whatever,) with points deducted for each second over or under that time. Timing stops when the model touches the ground or any ground based object (even a tall weed.) Landing points are also awarded for stopping the model's nose at an exact spot on the ground, with points being deducted for every three inches from that spot. In theory, at least, this is an extremely simple form of contest to run and to score.

We generally flew at sod farms, at open public parks, and occasionally at a polo field for this sort of contest, as they were all well mowed and relatively flat. Each had its own form of peril, however. The contest I am describing today was on a sod farm. "Farm" is a key word, here. Although sod farms don't generally have tall buildings (except for the one with the window I broke when a novice,) they do tend to have neighboring farms with vicious dogs and silos. When all the surrounding land is flat, the small complex of farm buildings, house, trees, and silo tend to be a spot at which upward thermal currents will "kick off." No small amount of courage or stupidity is required to fly over them, in the hope of catching lift at low altitude, when one is flying a small model at long distance and has poor depth perception. Yeah. I hit the silo.

Actually, I more or less landed on its domed tin roof, resulting in a resounding "BONK!" sort of noise. Flight timing stopped, as silos are definitely considered ground based objects, and a great susurrus of hilarity surrounded the red-faced Doc. End of story? Nooo! What occurred next was almost as much a surprise to me as it was to the laughing contestants. My sailplane started to slide down the dome of the silo, and as it fell off the edge, reached flight speed. In doing so, I was again flying and in control. For one of the few times in my life that I have thought quickly enough to surprise people, I remembered landing points! Apparently nobody else did, so it came quite unexpectedly when I yelled "Heads up!" and made a fast, diving glide to the landing point. I don't honestly recall whether I flew around or under the fabric top of the scoring tent, but I stuck the landing within two feet of the perfect spot. After a good deal of rule checking, discussion, and the consumption of cooler beverages, it was determined that the two aspects of scoring were indeed separate, and I was entitled to the landing points in addition to the flight points I had earned. This misadventure rated a specially drawn cartoon in the following month's issue of Soaring Flight, and a reputation I have never quite lived down. It was truly the most humiliating, yet the finest saved contest flight I have ever made.

Peace, Doc

"A failure is a man who has blundered but is not capable of c(r)ashing in on the experience." - Elbert Hubbard

The Birds

Mon, 28 May 2007 23:13:31 GMT

Once upon a time, long ago and high above, I was flying a little two-meter wingspan radio control glider. It was a fun-flying morning with only a young couple and myself at the flying field. I was expecting nothing other than a little relaxation and some conversation. The picture below, however, ended up being published in the soaring column of Model Aviation magazine. I wish I could claim I was special in some way, but the truth is that my model and I were simply in the right place at the right time and the young woman had a camera to capture the moment. On another occasion shortly after graduating to bifocals, she caught a picture of me hitting myself in the shins with a standard class sailplane while trying to make a precision landing. Events seem to equal out that way.

On the morning this picture was taken, I was using a simple "Hi-Start" (a slingshot-like device made of about 100 feet of stretchy surgical tubing and some heavy nylon string) which launched the glider to a height of about 400 feet. From there on, one either finds lift in a thermal (air rising faster than the model is descending) or lands in about two minutes to try again. With the upward twitch of one wing, I knew there was thermal activity and turned back in the direction of the wing that had risen and began to search for the area of greatest lift. On that day it was very easy to find the usually invisible updraft as it was populated by migrating hawks. Circling raptors or buzzards are always a good indication of the presence of a thermal because they do it for a living and not as a hobby. I was ecstatic and flew with them for several minutes. I'm not sure that they were as happy to have my glider present because I couldn't determine precise altitude and more than one of the hawks had to take evasive maneuvers to avoid flying into it. As far as they were concerned, I was doing the equivalent of driving the wrong way on a one-way street.

There were 127 hawks in the original picture, but to be published, it had to be converted to black and white, cropped, and the section with the glider in it enhanced in a friend's darkroom for visibility. When I scanned it for this post, I lost even more definition and modified it further for better contrast. Still, it marked one of those "once in a lifetime" moments that one feels privileged to have been a part of and never forgets.

After following the thermal and the hawks as far as I could, I returned the model to the landing area and sighed. When I looked back up at the sky again, I saw the approaching thermal train with at least as many hawks in each of the two following thermals, with a few stragglers in the next. At the time, I thought hawks were always very territorial and didn't know that they ever migrated in large groups. Previously I had never seen more than three or four in the sky at the same time. After some research and questioning, I believe that these were Broadtail Hawks heading South for the coming winter. Perhaps when I get the house sold I can migrate, too.

Peace, Doc

When I talked with my good friend, who also happened to be the editor of the soaring column in which the picture was published, I asked how many birds he thought were present. "That's easy. Just count the talons and divide by ten." - Dan Pruss

Doc's Place: Hobbies

The Bonk Heard 'Round The Sod Farm

The Birds