The Wrong Jump

My buddy and I had only been full cave for a few months and wanted to practice doing some jumps, especially in a low area that demanded better silt control. We had done the horseshoe circuit at JB before, following a more experienced diver who knew how to set up the circuit. It was weeks later, but we thought we could easily find the correct jumps and do the dive by ourselves.

The horseshoe circuit is best set up by setting the jump reel at the exit point back to the mainline first and then going back down the mainline to the initial jump. That way you have continuous line at both ends, in case you had to turn it. We decided that since we thought we knew the circuit well enough we would just set the deeper jump and go ahead and swim it around to the second, in effect swimming it backwards. Well, after kitting up, safety checks and primary tie off we dropped down into the initial big room at 90 feet and the lead diver started to look for the jump line.

It turns out that there are actually two jump lines within 10-15 feet of each other, both of which transition into a low bedding plane. The one on the left is the horseshoe, which loops in a horseshoe-shaped fashion back to the left. The right line, we learned later, dog legs to the right and parallels the main passage for a couple hundred feet before terminating back in the main tunnel. He jumped to the one on the right, where I thought it should have been the one on the left. But I shook off the doubt and trusted that he had the proper jump. I didn't say anything, which was our first mistake. We proceeded to swim down the line. It seemed slightly different than I remember, but I figured that since we were diving it backwards than from the first time it must just be the way the cave looks going the other way.

The tunnel is narrow, but fairly clean. I knew it had to start turning back to the left to make the horseshoe curve, but instead it headed slightly right and straight. In my mind, though, I was still convinced that we were in the horseshoe and that we would come up a shaft to the main 60 foot cave run that leads to the cavern zone. Instead, the line went through a small restriction. Beyond it I could see a larger room and my initial thought was "wow, we found a new part of the cave!". Remember this was only my 35th or so cave dive and only the 7th since full certification. When it came my turn to negotiate the restriction I had to wriggle in limited viz. I was nervous and breathing heavier than normal, but still in control. I popped out to see that the other side of the large tunnel we had entered had a gold mainline. I STILL tried to put what I was seeing into what I thought it should be and came up empty. All I could think of was that I didn't know where I was but I knew the way back was the way we had come. I called the dive and turned back into the restriction, attempting to lead the way back to known cave. Now it was zero vis and I made it even worse by wriggling on belly and back. I got some 20-30 feet back down into the side tunnel and waited for my buddy. No buddy. Covered my light, straining to see his. No light, no buddy. Oh, doo-doo. Now I was getting scared. Not for me, since I knew the way out, but for him.

I waited a bit longer and then decided to go back through the zero viz restriction for the third time. I popped out and found him there, waiting for me! We finally calmed down enough to pop out dive slates and started to "talk". About then I also started to recognize that we were indeed in the main JB tunnel, some 500 feet back (between the first and second breakdown) and that we could easily exit along the mainline. We both verified via slates that yes, we both knew where we were and that the prudent thing to do was to just exit along the main line. So we did. We exited with enough gas and our sanity preserved, and we had an excellent post dive discussion without any rancor about how we made a bunch of tiny errors that cumulated into a near miss.

I didn't challenge his choice of jump, even though it felt wrong. Both of us stubbornly refused to believe the "read" of the passageway and insisted independently that we were on track. When presented with different information at the end of the jump line, we interpreted it differently and rather than take the time to stop and communicate effectively, I bolted back the way we had came. He chose not to follow me, which added more stress. Luckily I ended up doing the right thing by going back to him and we both had cool enough heads to realize our mistake. I like to think that the cave tested us that day and that we survived as smarter cave divers and better buddies.