by Ronal Kerbo » Nov 21, 2009 12:07 pm
This may be too long a post and in the wrong place but to answer your question: The balloon efforts in Carlsbad Cavern were born during a walk through the Main Corridor of the cave with Albuquerque New Mexico caver Jim Hardy in about 1979. We had stopped just above the formation know as the Baby Hippo and Jim pointed up to the ceiling and a ledge of rock protruding out, just a little off center of the corridor, "Up there," he said, "could be the continuation of the Main Corridor on a higher level. If someone could get up there it might go." Yeah, I though and if pigs had wings--. So how the hell would I get up there? Carefully, I though, that doesn't look very safe, at least from here. On my off time I started going into the cave with binoculars, laying down on a bench near that lead and just staring at it, trying to figure out how to get up to the ledge without damaging the cave.
Finally I hit on the idea of using helium filled balloons to float a light line up and over the ledge. I discussed my idea with my friend, caver and a geologist, Mike Queen. Mike and I had been pushing other high leads in the Cavern and I thought he might buy into the idea of hanging a rope over a ledge high off the floor of the cave and climbing up to see what might be discovered.
As our plan evolved we thought we thought that one large balloon would do the trick but as we looked at the ledge we realized that we could not get the apex of the line high enough before the balloon would hit the ceiling. As time went on we decided to use two bunches of balloons to get a wider span between the lift lines without having the balloons hit the ceiling. Mike designed and constructed a lightweight spreader composed of balsawood, redwood, and waxed silk thread. The idea was to maintain a separation between the lines being lifted by the two sets of balloons. In the high humidity of the cave the wooden “spreader” just wiggled around, required more balloons to get it aloft and finally proved unnecessary to the effort. We simply placed the balloons far enough apart on the line to allow us to float up what for our use acted as two independent lines joined by a sagging line between the balloons.
The Spirit World attempt in the Big Room of Carlsbad proved to be more difficult because the stalagmites we were trying to reach were set back above a jutting bulge of flowstone. There we needed to devise a “hoop” of balsa wood that would allow us to reach back far enough to settle the line over the stalagmites. The front of the hoop was lifted by two bunches of balloons and the back of it was held level with two plastic dry cleaning cloths bags heat sealed by ranger Tom Bemis with his clothes iron and also filled with helium. This effort also took several nights and a number of people helping us to get the lines up and over the stalagmites.
Several times people have asked why we did not just float a camera up into the leads rather than floating up lines and then pulling up ropes. It would take a lot less energy and also not be as risky as climbing up ropes looped over questionable anchors. My answer has always been that if the camera showed a going lead you have to climb up, if the camera showed no lead, how could you trust the damn thing and you would have to climb up just to make sure, so why waste time messing about with cameras and miss all the fun of climbing up ropes looped over questionable anchors!