Add a skill: Square Spiral Search

Sometime in your diving adventures, you’ll end up losing something underwater that you really don’t want to have to replace. Maybe it’s only a mask or a snorkel, or maybe it’s a wrist mounted computer that cost you a pretty penny. In a separate article, I’ll review how to make a better wrist mount to avoid losing your computer in the first place, (hint: checkout the commercial version of the solution here, and from there it’s pretty easy to imagine how to make your own if you’d rather) but for now let’s return to how to find something you’ve lost. If you have a good idea where you last saw the item, and you have a compass (which you really should), my favorite search pattern to try is the square spiral search, also called the expanding square search. Obviously, you need to have some familiarity with compass navigation to use this search pattern, although not much. If you’re a little rusty on compass navigation, check out my review.

Square Spiral

As illustrated in the figure above, the idea behind a square spiral search is straightforward: kick once, turn 90 degrees counterclockwise, repeat, kick twice, turn 90 degrees, repeat, kick three times, etc. In very good visibility or with a brightly colored lost object you may be tempted to add two kicks every two turns, or use really long / powerful kicks, but I don’t recommend it, for a couple of reasons. The first reason is that even in the best of situations, when you find what you were looking for, you’ll be amazed how often you almost missed it even when going very slowly and carefully- it may be partially buried in the sand, for example. The second reason is that you’ll be doing this with a buddy who has to keep up with you, possibly in poor visibility, as explained below.

BUDDY SYSTEM: As with most recreational diving, the buddy system is an important part of doing a square spiral search. Basically, it’s difficult to watch a compass and look for a dropped object at the same time. This is where teamwork comes in. In this search pattern, one buddy works full time on counting kicks, and navigating 90 degree turns using the compass. So this buddy would start where you believe you’ve dropped the item, point their compass along a heading of 0 degrees, and kick once. The second buddy would follow the first buddy, focusing carefully on the bottom, and keeping the first navigating buddy in the same spot in their peripheral vision as they follow along. Next, the navigating buddy would pause to let the searching buddy catch up, turn to a heading of 90 degrees, and make 1 kick. Next would be two kicks at a heading of 180, followed by 2 at 270, etc.

SLOW AND EASY: In decent conditions it may be tempting to skip the beginning, close-in part of the spiral, since you will be covering a small space and reviewing the same patch of bottom for the first couple of turns. Sticking with these beginning tight turns is actually a great idea, and here’s why: kicking past the same bottom features a few times at the beginning of the spiral allows the navigating buddy to gauge how wide a stretch of bottom can easily be seen at once from your height and with your visibility, for this search. This lets this buddy adjust the strength of their kicks, to be sure that on each leg of the spiral, you’re seeing overlapping swaths of the bottom and not skipping any regions by going too quickly. If the searching buddy needs to ask for a longer or (more likely) shorter kick to ensure this overlap as the search progresses, simple bigger/smaller hand gestures (placing the two hands palms facing, and either pushing them together or pulling them apart) can be used to communicate this information.

If you’re dealing with a rough bottom, as you search widens, you may find obstacles along the bottom. In great visibility you may just be able to work at a depth above all small bottom features, but if you must deviate around them, I like to do a full circuit of the base of the feature, spiral up it if it could be supporting your lost item, and then continue the search pattern on the far side of the obstacle as planned.

PROPER PREVIOUS PLANNING PREVENTS POOR PERFORMANCE: The law of the six P’s is as applicable here as it is everywhere else in diving. During a meltdown about the loss of your new $1000 wireless computer is not the best time for you and your buddy to practice your first attempt at a square spiral search. You’ll notice when you try it that it can be a bit task-loading at first, but that a little practice goes a long way, and once you’ve gotten the hang of it you’ll find it to be a piece of cake when a real situation arises. My advice is to get a 2 pound soft shot weight pouch, the small black (i.e. hard to spot) ones, and use it as your practice “lost item” in shallow water. Have a third buddy toss it and observe where it falls while your backs are turned, and then have this buddy point you in the general direction of where the item was “lost” so you can begin your search. Obviously, if there are any delicate corals, etc. below rather than sandy bottom, have the third buddy place it gently on the bottom instead and surface to tell you where to begin searching. If the vis and conditions are especially nice and you want to really test your new skills, you may want to try a penny instead, and/or try having your third buddy point you slightly off course so that you have to spiral out a bit to reach the place the item was dropped.

Finally, while you’re doing your search, you still need to be doing all the usual diving things like monitoring your remaining air and your depth. My method is, at every other corner, when you pause with your buddy to make the turn, take a look at your gauges or computer. By planning to check this more often than absolutely necessary, you leave yourself a margin of error in case you miss a check once in a while.

Once you’ve practice a couple of times in each of the two roles, you’ll have a new tool at your disposal the next time a piece of gear tries to escape into Davy Jones’ locker. Although the square spiral is my favorite for recovering dropped scuba gear, for other situations, there are other search patterns, (for example, the jackstay search), which we’ll cover in future articles.

If you’ve found this tutorial helpful, please consider making a small donation! Thanks and happy diving!


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