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Underwater Navigation and It’s Importance

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In my experience as a diver and now Open Water Scuba Instructor it has come to my attention that many divers possess less than optimal skills when it comes to the area of navigation under water. What I hope to convey through this article is to simply address the benefits of developing the skill, pass on some tips as to how this can be done, offer advice on practicing the skill, address the safety concerns, and make using Underwater Navigation fun. If these items are addressed and convince divers to develop the skill it will have served its purpose. If nothing else I hope it will at least get divers to think more about how it can benefit them and instructors to address it to a greater degree than they do now.

When I first got certified as an Open Water Diver there was another diver who was going thru his Divemaster internship. One of his tasks was to lead me on an underwater tour. This was on my first dive post checkouts and leading up to AOW. We were diving the same spot that I had during checkouts. The difference was instead of following the lines we followed a compass and natural features course that he knew well. During that dive we used buoyancy control, he had me monitor our depth, note features, and most of all stay in proper position for ease of communication and in case one of us would need any type of assistance. What stuck with me though was his seemingly uncanny sense of direction. We went on a swim of nearly 45 minutes in 10-15 foot vis and came back to within a few yards of our starting point. This has stuck with me throughout my diving career and influenced much of my learning.

First of all what it did was give me an example of what kind of proficiency is possible if you work at it. This can be applied to any skill set. Next it demonstrated the value of mastering buoyancy control as on several legs we swam back along a reciprocal course and had we not been in good trim and using anti-silting kicks we would have had serious difficulties. And it also clearly demonstrated the value of swimming slowly, taking our time, and not rushing around using up air, missing landmarks, or overshooting distances. All of these benefits are available to any diver who wishes to work for them. And all are a result of striving to improve Underwater Navigation skills.

Let’s begin with the basics. There are generally two types of navigation used by recreational or open water divers, compass and natural. Natural is actually a subjective term since much of what divers use for natural features may actually be manmade or deliberately placed. Lines in quarries from platforms to boats or markers are actually used to aid navigation. They help divers find their way yet do not often require a compass. Compass navigation while taking a bit of skill and practice is not difficult. Although like my early mentor there are divers who make it look like magic. In order to be effective at underwater navigation we need to have a few other things in place first. Being really comfortable in the water is one, some experience with dive planning, and most importantly good buoyancy control and trim. As seen below in the divers using natural navigation while maintaining optimal position for communication.

Let’s take a brief look at these before getting into actual techniques and the real benefits of being a successful navigator. Comfort in the water is often taken for granted by divers with some experience. And frankly it should also not be an issue for new divers. Unfortunately we all know that this is not always the case. When we introduce a new task to a diver, being comfortable in the water goes a long way towards achieving success at that task. Every diver should take the steps necessary to feel comfortable in the environment. It is the duty of every conscientious instructor to see to it that the diver they issue a certification card to have the necessary level of comfort in the water to successfully plan, execute, and return from a dive.

Like diver comfort, the ability to plan a dive is in the basic description of every agency when it comes to the open water diver. It is commonly stated as the ability to “plan, execute, and return from a dive with a buddy of equal skill and training in conditions equal to or better than that in which they’ve been trained without the assistance of a dive professional”. We all know that this is too often not the case with newly certified divers. So how can we use underwater navigation to aid the new diver? It is my opinion that by introducing and offering the skill sets needed in UW Navigation we not only can encourage the new diver to improve their skills overall, but add to their confidence level. These can not help but have the effect of increasing their overall comfort. It is my contention that we not look at Underwater Navigation as simply a course in itself. I like to look at it as a way to improve every aspect of the dive experience. By simply being able to find your way to one point and return to your starting point you utilize more than just a compass, line, or a few features. The diver is required to use good dive planning, buddy skills, buoyancy control, and gas management. In short a good navigation course can greatly add to every facet of a diver’s skills!

Now what does a good navigation course consist of. Nearly every certification agency offers a course in underwater navigation. Some are more extensive than others but all contain some basic items in common. These include using a compass, using natural features, discussing some hazards and obstacles, measuring distances, and the dives themselves. These can vary in number and duration but are usually in the range or 3-4 dives. While this is usually sufficient to impart the basics it is often done without assessing the divers other skills. If one, for instance, has poor buoyancy control none of these dives will result in the student actually getting the full benefit of the exercise. One of the things I recommend to those wishing to take a Navigation course is to take an honest look at their basic skills. Mainly in these areas:

1.     Buoyancy control. What used to be taken for a basic skill is now often overlooked in OW classes. For this reason it pays to take an honest look at how well you are able to control your place in the water column. If for example you are still having issues with using lung volume to adjust your depth then perhaps you need to work on that before undertaking a serious Navigation course. In order to successfully navigate over a silty bottom or one with many obstacles you do not need to be grabbing your inflator every two seconds. By mastering using breath control to make these adjustments you actually reduce the amount of task loading. One of the best ways to manage task loading is to reduce the number of tasks you need to manage. Practicing good buoyancy control should ideally begin the first night in the pool on scuba. If it does not what often happens is that bad habits begin to form and once they do it takes real effort to break them. Proper weighting, another skill set that should be introduced in OW class is essential to buoyancy control.

2.     Trim. Trim goes hand in hand with buoyancy control when it comes to successful navigation techniques. Ideally a diver is horizontal in the water with the feet slightly elevated. Using either a modified frog kick or frog kick. In this posture they are able to swim and not disturb the bottom. This is very handy for divers behind them and when they need to retrace their course. If you are not able to hold good trim, as with buoyancy, getting the most from a good nav course will be seriously hindered. An honest assessment by an instructor or an experienced diver with good trim is the best way to determine your level of proficiency when it comes to trim. As with buoyancy control, weighting is also critical but here positioning of the weights is as critical as the amount.

3.     Propulsion techniques. For most recreational diving the standard flutter kick is sufficient. As long as the diver remains a reasonable distance from the bottom. When we actually begin to get serious with navigation it is frequently not the best choice. When using natural features especially where the bottom is used as one of the features, the flutter or scissor kick is more of a hindrance than a help. It is here that the frog or modified frog is the best choice. If you have not found your “inner frog” as yet now is the time to do so. Not only does a good frog kick result in less disturbance of the bottom but it is easier on the legs. Practice with the kick will also result in the diver being able to maintain a steady pace for longer distances which is a key aspect of navigation under water.

4.     Turning Underwater. Turning underwater goes along with propulsion techniques as a skill useful for navigation. When doing squares, triangles, or reciprocal courses the technique known as a helicopter turn saves time, reduces effort, and helps to keep turns more accurate. A helicopter turn also eliminates the need to get vertical in order to make a turn as many are taught to do. By simply moving one ankle a diver can rotate about a fixed point and therefore keep in trim and stay focused on his/her compass. Making course changes more accurate and easier.

5.     Pace. The pace at which you swim can make or break a navigation exercise. Hopefully you were told over and over that under water it is not a race. When you have your kick down and begin to use it on a regular basis you will begin to swim at a pace that is comfortable, affords good control, and is easy to maintain. It will also likely be a less than flat out sprint. By slowing down and being aware of your speed and at what speed you are able to perform basic tasks you will adopt and use this. One other major factor in the pace of the dive is the speed of your buddy. Ideally it was also stressed that the slowest diver sets the pace of the dive. Period. End of discussion. If you and your buddy are constantly playing catch up it is difficult to successfully work as a team. And Navigation is a team skill as much as it is an individual skill.

6.     Position. When divers are navigating as a buddy pair or team the position of the divers becomes another important part of the exercise. Ideally they should be in such a position as to make it a matter of a slight turn of the head to know where each person is. By having the divers in such a position it is easier to concentrate on the actual task of navigation, communicate with each other, and lessen the chance of diver separation. It is also important when diving as a team in proper position to determine who will be doing what tasks. For example if the diver using the compass will initiate turns then the other should be on whatever side will not cause a problem for the compass holder. I.e. if you are turning right the compass user will be on the right to avoid a collision.

Once you have taken a look at these areas and are satisfied with your skills in each of them it is time to start taking a look at the skills you will need to successfully begin developing your navigation skills beyond the basics. It’s at this point that you will need to work on your compass skills, observation skills, data recording, and documentation or map making skills. While all of these sound obvious they evidently are not among many recreational divers. Otherwise there would be no need to discuss the issue. Divers would be told of the importance of being able to navigate from day one. Even if they did not get all the skills in OW class they should at least be told how to use a compass and natural features to find their way around underwater. And get a chance to practice those skills on one or more of their checkout dives. Many agencies require the use of a compass on one dive and instructors will give a briefing of the site. This is usually sufficient to meet the standards of the agency but does not do a whole lot for the student as far as reinforcing the idea that UW Navigation is a very good skill to have. I actually do the following with this. I will take one dive, give the students a heading and allow them to lead me on the dive. This reinforces the idea of compass skills being important and gives them a real chance to see for themselves.

Once we have established these basic skills, UW Navigation is a relatively simple matter to teach. The most common methods of navigation we can ask of students are compass, and of course natural. Taking compass first there are only a few fundamental skills they need to use in the beginning.

They include holding the compass level, knowing how to read it, how to set a course, change a course, and actually trust the compass. For natural navigation the skills of observation, recording of details, and knowledge of the environment are the most commonly used and needed. If we take each by itself they can also impart valuable lessons that will benefit the overall skill of the diver. Let’s look at each one.

1.     Holding the compass. Depending on the type of compass used there are a few ways to hold it. How depends on a few things such as is the compass in wrist mount, console, or on a retractor. It may even be mounted on a slate. No matter the type of mount the primary thing to keep in mind is to hold the compass level. Not holding it level can result it the needle or compass card getting stuck and giving a false reading. There are compasses that are supposed to be accurate even though held at up to a 30 degree angle. Regardless of this not holding it level is a bad habit to get into. Because at some time you will get a compass that cannot be tilted like this and the course you take will be off. Holding it level is accomplished in several different ways. First is the two hand method in which the console, or compass if using a retractor, slate, or module itself, is cupped and the elbows tucked in tight to the body. Holding the compass in this manner allows one to keep the lubber line in line with the body. It also necessitates the use of good buoyancy control and horizontal trim. Another method with a wrist mount is usually taught by extending the arm the compass is not on in front of the body, and grasping just behind the elbow to form a right angle. The compass/lubber line is then again in line with the body. But if the divers buoyancy and trim are off then again the course will not be accurate. A big benefit of using these methods is it requires the diver to work on his/her buoyancy and trim. Something that is all too often lacking in new divers today.

2.     How to read a compass. A compass is read by looking at it from the top or by using the sight window if it is so equipped. We read it by setting a heading and lining up the point of the needle in between the reference marks. Sounds simple, and it is. By itself. But when we are also required to monitor depth, time, air pressure, and perhaps natural features it becomes a real exercise in task loading. As such there are number of real benefits to the divers other skills. In addition to the previously mentioned buoyancy and trim we are now required to maintain a steady pace, swim without rocking from side to side, and have more situational awareness. One way to do this is to add to our resources by using our dive buddy to handle some of these tasks. In doing this we gain the added benefit of improving our buddy skills. Again we all too often see buddies who are no more than same ocean/lake/quarry buddies. They do not swim together or at the same pace. Beginning in OW class they hear about the buddy system but they are not required or even shown how to properly implement it. By practicing UW Navigation their skills in the area of diving with a buddy are improved.

3.     How to set a course. Setting a course is another relatively simple matter. You take a heading as noted previously and maintain it. When actually setting the heading though there are a few things to consider in conjunction with your buddy. First of all is whose compass do you use. Compasses can vary by up to 10 degrees in their readings. If both are using their own then this needs to be determined before setting out on a course. To do this take a bearing on a fixed point on the surface and compare readings. Do this for several points to be sure of the deviation if any. Then select the course or point you wish to find and decide who will do the navigating and who will monitor the other key factors of the dive. It is best to choose one compass and stay with that throughout the dive. The chief benefit of doing this is that it improves the communication skills of the divers in addition to their navigation skills.

4.     Changing a course- Changing a course is another skill that when done properly results in greater accuracy and less stress on the divers. This has the tendency to result in better air consumption and less effort. Changing course properly starts before the dive even begins. The buddy pair or team will decide on the objective, note when course chances are to be made, decide on positioning, and execute the dive. To do proper course changes with a minimum of deviation it will be necessary to master swimming pace, and precise turns. Also called helicopter turns these are used by tech/cave/wreck divers to navigate tight spaces without causing silting. They are just as useful for recreational divers and simple to learn with a minimum amount of instruction from an instructor or mentor who is well versed in them. They as well require good buoyancy and trim and once mastered have the same benefits as previously mentioned with the added benefit of being able to maneuver with great precision. When a diver is able to execute good helicopter turns changing course is easy. When turning to the right we add to our original heading and turning left we subtract. To make 90 degree right turn from a 130 degree heading we reach the turn point, in a horizontal position we stop, turn the compass to the new heading of 220 degrees, and execute the turn remaining horizontal and in good trim. Practicing these turns along with the other skills has the potential to turn an average diver into an exceptional one with buoyancy and trim skills far above what is many times encountered.

5.     Trusting the compass. This last skill in compass navigation is often the most difficult to master and usually takes the most practice. Many of us believe we have an “internal compass” that seems to really kick in when we actually need it the least. Such as when we are midway through a dive and another diver ruins the visibility by stirring up the bottom. We know we should trust the compass but after swimming for what seems too long and not seeing what we expect we begin to doubt it. Then the internal kicks in and says “dummy, you must have been off by a few degrees!” So we turn this way, then that way, the in an effort to settle it once and for all, perhaps we surface, locate our exit point or point of interest and find out that had we stayed on the compass course for another few kick cycles we would have been right where we wanted to be. What happens here is that we fall back on a basic idea that our senses are more reliable than a mechanical device. This is not at all exclusive to use of a compass or even diving. What we need to work on is the ability to trust something outside our selves to aid us in task. The benefit of this in other areas is that we develop a degree of comfort with our abilities. This translates into again diver confidence, comfort, and safety. It also teaches the diver to rely on his or her equipment which requires the diver to become more familiar with it.

Natural Navigation is similar to compass navigation except that the tool we use is the actual underwater environment itself. As stated earlier natural is a subjective term because the “natural” features we may use could have been placed, abandoned, or otherwise deposited by man. In any case what are required for natural navigation are some new abilities in addition to those used in compass navigation. Noteworthy of these are the following. The ability to record or other wise recall details, choose points of interest, and document the site. As we did with compass navigation we will look at each of these in turn and assess their overall benefits beyond navigating a course.

1: Record and recall details. When we use natural navigation we need to pay attention to details as these are the items we will use to find our way back to our entry point. But simply paying attention is not enough. We must have some way to recall these details. If we were not task loaded enough with just the act of being underwater on scuba we now have to contend with multiple points, in a specific order to allow us to return to our starting point or to find a specific point or location. This is mentally possible for some people, especially after a bit of practice, but in the beginning actually recording these details are the best method. As we all know there are different ways to record such items. We can use a slate or wetnotes. Whatever method we choose we need to realize we may only have limited space and time to record these details. As such we must choose a way to make notes that are clear, concise, and above all, brief. There is no set way to do this. It is up to the individual diver or team to determine the words, symbols, characters, or pictures you will use to do this. Once you have selected a method stick with it. Become proficient in its use and make use of it whenever possible. By doing this you will develop a routine that will reinforce other things you need to do on a regular basis. Equipment checks, weight and bubble checks, and planning the overall dive are all necessary for successful diving. When we establish routines they become instinctual and second nature. The result of this is a safer dive due to greater attention to the details that make a safe dive.

Click to enlarge

2: Choosing points of interest. Once you select a method to record details and points of interest you now need to actually decide what points to select. There are so many variables here due to location, conditions, the availability of actual points, etc. So what are some general guidelines we can use when selecting features? In general we want to pick objects that first of all are stationary! If it moves it may move between the time we select it and the time we come back. This is not a good thing! There are times when a non stationary object may be used if we can be sure that it will be there when we get back. Such an occasion may be when there are no other divers in the water and we ourselves place some type of marker to use as a reference. But usually we do not do this. Now the features we select can be truly natural ones or those that have in some way been placed by man or the elements. In any case we need to consider some other factors in addition to the object staying put. We need to be sure we can distinguish the object upon our return. This means choosing truly distinctive ones and once selecting them looking at them from the angle we will be returning to them! In fact we need to look at them from every angle if there are other similar features such as coral heads, tree stumps, etc. The benefit of doing this is that it increases our situational awareness, observation skills, and sharpens our senses. This in turn leads to greater safety in the water and again increased confidence and comfort. This brain coral would make an excellent reference as it sits on a nice sandy spot by itself and would be easy to relocate.

3: Documenting the site. When I speak of documenting the site I am talking about map making. Map making need not be elaborate or a work of art. It needs to be legible, clear, concise, and above all usable by all who intend to use it. Creating a map is done by first using the details we have recorded, getting an overall view of the site sketched out, and combining the information. Once we have done the initial map we now need to augment it by adding details. We do this by returning and diving the site over an over. Each time we add details by changing our course just a bit. The more we do this the more detailed the map becomes. The more detailed the greater the knowledge of the site. The benefit to our other skills is as already stated in addition to more time underwater. This gives us the opportunity to improve our basic skills, propulsion, buoyancy, and trim. In short we dive more and stay sharp.

We could at this point begin to cover in detail the many different ways to navigate a course and actually do an exercise using them. But that is not the point of this presentation. I hope that by covering the things I did that I gave you food for thought. That you now have some idea of the benefits of using underwater navigation and perhaps taking a good Underwater Navigation class. Not only will you improve your navigation skills but by doing so improve your overall dive skills and adding to your confidence, comfort, enjoyment, and most of all safety.

By James A Lapenta SEI Instructor #204


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Comments

  • Ariel Livaudais said:

    Mr. Lapenta,
    This is an excellent article; well written and very informative. I came away with a clear understanding of the requisite knowledge for good navigation as well as having to take a good look at where my current skills are. I am a new diver, with under 10 dives to date. I already knew that my training was not as good as it could have been and that much of my learning would be through experience. I believe the lackluster training was due to a combination of factors such as my inexperience, the fast pace of the course and, from what I understand, a general dumbing-down of the course material in an attempt to make diving more attractive and accessible to newbies. I understand that it is in the spirit of attracting more people to recreational diving, but at a tremendous, and avoidable cost. At any rate, I do know what basic skills I need to improve on and I am even more motivated to get in water and get busy, thanks to your post.

    Thank you,
    Ariel

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