Thailand – Australia – United Kingdom

Complex Cave Diving Navigation

Complex navigation in the cave environment is critically important. Taught at the Apprentice Cave Diver level, it is further refined at the full Cave Diver level. At the Cavern and Basic/Intro Cave Diver levels we discourage complex navigation and train divers to stay on the main line. No jumps, no circuits, and no traverses. Cave diving fatalities have occurred when team members mismanaged complex navigation and lost their reference to the direction of the exit.

Skill Review

In the last couple of issues of the Underwater Speleology I have reviewed “How to” scenarios: How to relocate a lost buddy and how to relocate a lost guideline. I encourage you to re-read those articles with special attention paid to the primary sources of trouble: lack of awareness in the cave, failure to use a continuous guideline, and the direct link between increased task loading and decreased awareness.

The modular programs in cave training take advantage of compartmentalizing chunks of training and, by design, save complex navigation for the latter half of training. The reasoning for this is that the task loading cave students undergo at the cavern and basic cave levels (things such as how to properly deploy a reel, buddy awareness, line awareness, overall situational awareness, and dive technique) should be mastered and in muscle memory before more complex dive plans are made and students begin using one third of their gas supply for penetration.

Plan Your Dive

Once a dive plan is made that includes jumping off of the mainline onto another line, the following procedures help the team stay focused on the task of more complex navigation and helps prevent them from “going the wrong way” during their exit.

Divers should always run a reel to the main line and for all jumps. Proper directional markings are essential for safely navigating to the exit. Relying upon memory or someone else is not the safe way to do this. In low or no visibility we realize that it is very easy to become disoriented and go the wrong way.

Dive Your Plan

Once in the cave at the agreed-upon jumps, one teammate designated to install the jump reel should locate the line they are jumping to. He/she should deploy the jump reel, tying in to the other line, to make a continuous guideline back to the exit. The other teammates should wait on the mainline providing light for the teammate deploying the reel, as well as verifying that the jump is done correctly.

Most popular jumps have double line arrows indicating both that a jump exists in the vicinity and indicates the nearest exit direction. If there are no arrows on your jump, place one that can be identified as yours by sight and touch once you return to that line/jump point. Once the designated teammate installs the jump reel he or she will OK the other teammates with his or her light and only then do the other teammates cross to the new line. Once crossed the teammates should inspect the tie off also inspect the reel to ensure they can identify it as their team’s reel once they return. Reels should also be prepared in such a way that they can be identified by touch.

The team is then safe to continue into the cave until someone turns the dive and the team begins its exit. At this point the team’s approach to safely navigating out of the cave is critical, partially dependent upon how the jump line was initially installed and marked.

Safe Exit

After the team turns the dive and once the team reaches the point where the jump was made all teammates, except the team member running the reel, cross to the other line and wait for the reel person on the exit side of the jump. This helps set up the proper exit direction and the proper team order is not changed.

The person responsible for pulling the jump reel should wait at the reel and ensure his/her teammates have each made the jump and are waiting on the exit side before untying the reel from the line. Once all teammates are on the exit side the team member managing the reel can remove it.

Low- or No-Vis Exit

This method is relatively simple and works very well in good visibility. If the team is exiting in low or no visibility the reel(s) should just be left in place. These procedures help ensure that each teammate is thinking about the navigation and is not just following another teammate. Each cave diver is verifying and validating this phase of the dive, as they must also be doing during all phases and transitions during the dive. — Text by Jim Wyatt (photo by Jill Heinreth)

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