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acelockco
07-09-2007, 04:41 PM
In another post BamaCaveDiver brought up something that I thought would make a great discussion. He said Plan Your Dive & Dive Your Plan. That is something I have heard before, but don't know much about.

So what does it mean exactly to Plan Your Dive & Dive Your Plan? I know it sounds obvious but I need to know what it really means in black and white. I also want to know why you feel it is important or not important.


Ace:confused:

Grateful Diver
07-09-2007, 05:00 PM
As someone who teaches scuba diving, one of my pet peeves has always been the tendency to tell students what they should do ... while at the same time neglecting to instruct them on how to do it.

"End the dive with 500 psi" is another slogan you'll often get without any clues as to how, exactly, you're supposed to go about it ... and they're related.

"Plan your dive and dive your plan" ...

At a conceptual level it implies that before getting in the water, you should have an idea of where you're going, how long you're going to remain there, and how you're going to get back. It's no different, really, than jumping in your car and going somewhere. You usually don't just jump in the car, drive around, and head back when you feel like it. You have a purpose, and you ... at some level ... plan how you're going to use the car to achieve that purpose.

With diving, "planning your dive" at a minimum should involve determining how deep you want to go, how long you intend to stay, and how much air you will need in your tank when you begin your ascent. "Diving your plan" means, simply, that once you've determined the above ... impose enough self-discipline on yourself to stick to what you had determined to do ... don't go deeper than you'd planned, don't stay longer, and start your ascent when your pressure gauge reaches the minimum level of air that you determined you'd need to end the dive with a safe reserve.

Gas management is one of the most important skills not taught by the major agencies. No one would consider taking a trip across a wilderness ... knowing that there are no gas stations along the way ... without having a pretty fair idea of whether they had enough gas to make it. And yet that's exactly what scuba divers often do when they jump in for a dive without knowing how much air they breathe, on average, and whether or not the air in their tank is sufficient for the depth they plan to go to or the amount of time they intend to stay. After all ... the air in your tank is all that you will have available until you get back to the surface ... wouldn't it be great to be assured that you're not going to run out before you've completed the dive? There are straightforward ways of determining that ... although at first it involves some measuring and some arithmetic. Once you know your consumption rate, though, you can actually plan a dive based on the amount of air you HAVE ... rather than having to perhaps cut it short because you used more than you thought you would.

Many (most?) divers get hung up on depth ... some chasing "personal best" depth records without really understanding either the risks involved or the preparation needed to do the dive safely. I have a rule of thumb for my students ... don't go deeper than the cubic feet of gas your tank will hold. In other words ... if you're diving an AL80, limit your dive to 80 feet. Sure, you CAN go deeper ... but it'll be either a short (bounce) dive or you'll be risking running out of air before you can complete your ascent safely.

Planning your dive also involves considering your own skill and training level, and asking yourself if it's adequate for the dive you want to do. What's your comfort level in the water? Can you hold a safety stop without having to hang onto something? Do you need to fin in order to hover? Are you comfortable in current ... or surge? Make sure you get some information on the type of conditions you're likely to encounter, and ask yourself if you're ready for those conditions ... and be honest with yourself, we all have a tendency to think we're more skilled than we actually are.

Another part of planning ... how am I getting out of the water? Am I diving from a boat or from a shore site? If a boat, will I need to get back to the anchor line or can I just surface anywhere and the boat will pick me up? If from shore, will I need to exit at a particular place? What kind of hazards (e.g. current, waves, boat traffic) might I anticipate on my exit? All of this must be considered in the "plan your dive" phase ... never get into the water without first knowing how you're going to get out.

Planning your dive, really, means thinking about all of those things and having a pretty good idea ... before you ever get in the water ... what type of dive you want to do. It means having considered your skills and equipment and deciding that they are adequate to do that dive with a relative amount of safety and comfort ... diving's all about having fun, after all.

Diving your plan means sticking to the dive you'd planned ... don't go deeper, don't stay longer. There's a great peace of mind that comes from knowing ... because you thought about it in advance ... that you can safely handle the dive you're doing. It helps you relax ... and that helps you enjoy the dive more.

... Bob (Grateful Diver)

BamaCaveDiver
07-09-2007, 05:46 PM
That is indeed a great question Ace, and I think Bob has given one of the best explanations that I have yet to see. As he stated, dive planning is all about recognizing your limitations on dry land before you ever splash, and designing your dive around those limitations. Divers who simply jump in with no clue as to how much gas they are carrying or how long that gas supply will last at their targeted depth, they are typically the ones that see something cool and get lured in. Just like the sailors of old who were said to have answered the call of the sirens, these divers may soon find themselves in a situation they are not prepared to deal with. Having a dive plan allows you to look ahead at possible emergency situations and formulate a plan for recognizing the early signs of impending disaster, as well as how to respond safely. Your dive plan, if correctly laid out and properly executed, will ensure that you return to the surface safely without the need for a rescue. If I see something cool, I tend to make a note of it on my slate and then plan my next dive to explore in more detail, as opposed to deviatng from my plan. Finally, a good dive plan can be a godsend for anyone having to do a recovery; a very close friend drowned back in February, and given the system he was in the team was not looking forward to the task ahead of them. Then they found his survey notes from previous dives and were able to piece together his last dive plan which took them straight to where the body was. That may seem a bit grisley, but that individual would not have wanted anyone risking their own lives to remove his lifeless corpse from that or any other system.

heelsfaninpa
07-09-2007, 06:34 PM
Bob, as a new diver, your idea of planning and mine are the same. After going through my recent certification class, planning is one of the things that they preached. However, I have made 8 dives thus far, and since I was diving with much more experienced divers, we really never came up with good dive plans. It was mostly "lets go to the fire truck, then to the airplane, then to the boat". By that time, I was almost out of air (i.e. just below 500#) and felt that I should have prepared even better.

In my work environment, I am a senior reactor operator at a nuclear power plant. Every job we do, every work week we execute, is planned down to the Nth degree. We always preach "plan the schedule, execute the plan". We also make safety our number one priority and in an industrial environment, that is extremely important. This is my idea of how diving should be. While it should mostly be fun, there is a certain safety aspect and protocol that must be followed.

On my future dives, no matter how much of a pain, I will plan my dives and dive my plan, ensuring the safety protocols are followed. I know I will feel much better if my buddy and I are safe throughout the dive. As we used to say on board our submarines (back in my navy days), "keep the surface-to-dive ratio at one".

Thanks for the advice.

acelockco
07-09-2007, 08:29 PM
Thank you so much for all of the great information. I was expecting some answers, but not such a great detailed explanation. That is exactly what I wanted.

Now Grateful Diver, where are you located because you sound like the type of instructor I could actually learn from?!

Grateful Diver
07-09-2007, 08:57 PM
Thank you so much for all of the great information. I was expecting some answers, but not such a great detailed explanation. That is exactly what I wanted.

Now Grateful Diver, where are you located because you sound like the type of instructor I could actually learn from?!

You're welcome ... I'm located in the Seattle, Washington area ...

... Bob (Grateful Diver)

lottie
07-10-2007, 03:11 AM
Even though Ace has already mentioned it - GratefulDiver that was a good post and goes into more detail than what I've learnt through my OW.

Just one thing to add as well - if you're diving with a buddy, also plan what to do when you can't find each other (you shouldn't have gone too far from your buddy in the first place) - but what I'm getting at is that you should plan, for example, to only stay in the water for a few minutes then surface.
I hope you understand the point that I'm trying to put across - that it's not just about you, yourself to plan, but also for your buddy as well.

It's late.....i need sleep

Nite John-boy
:)

acelockco
07-10-2007, 03:54 AM
Lottie,

You sound tired......if that is something you can do here.

LOL

Anyway, great point I think you should always discuss that with your buddy before you dive. I was always told the standard practice was to circle around looking for your buddy for 1 minute. If you don't find him/her then you begin your acent. If you both follow this, you buddy should be at the surface within minutes of you.

Now funny thing, most of the boat diving out here do not observe the buddy system and they never really have. I personally always do, but some do and many don't. The divers with doubles and sling bottles and such don't usually have a buddy, or they decend with someone and split up at the bottom.

hbh2oguard
07-10-2007, 06:42 AM
I really liked the cubic feet of the tank rule, something I never thought of and this post has been a great learning expierence.

lottie
07-10-2007, 12:29 PM
Ace - That was exactly what I was trying to say last night but my brain and fingers weren't in gear.

acelockco
07-10-2007, 01:55 PM
I understand, I often stay up late in the evening on the computer. I find my typing skills quickly get bad when I start to get tired.

LOL

Ace

Grateful Diver
07-10-2007, 02:33 PM
Anyway, great point I think you should always discuss that with your buddy before you dive. I was always told the standard practice was to circle around looking for your buddy for 1 minute. If you don't find him/her then you begin your acent. If you both follow this, you buddy should be at the surface within minutes of you.


About buddy diving ...

There are two main reasons new divers sometimes lose track of their dive buddy.

First off ... when you don a scuba mask, you lose your peripheral vision. All our life, we're used to being able to see "wide angle", being able to detect things on our periphery without having to turn our head. With a scuba mask on, your vision narrows and you have to train yourself to turn your head in order to keep track of what's going on around you. We call this learning "situational awareness" ... it's part mental and part physical, and takes conscious effort at first to learn.

The second reason divers will sometimes lose track of their dive buddy is because you weren't taught proper buddy diving skills. Too often you'll see divers swimming one in front and one in back ... and often the one in back, for one reason or another, will be behind and a little above. This works great for the diver in back ... they can see their buddy just fine. But the diver in front has to be constantly turning around to see if their buddy is there ... and that's a major distraction. If at some point the buddy in the back stops to look at something, the buddy in front isn't aware of it and keeps swimming. Next time he turns around the dive buddy isn't where he expects him to be.

Under most open water conditions, you and your dive buddy should be swimming side-by-side, where it's easy to see each other by simply turning your head a little bit. You should be swimming close enough to be able to quickly get each other's attention, and to be able to reach each other reasonably in an out-of-air emergency. If visibility is poor, you might want to be a little closer together to avoid losing each other. In very poor visibility, a dive light works well to maintain contact. Shine the light on the ground where your dive buddy can see it easily ... if he can see your light, he knows you're there.

In the event of separation, search a complete circle for one minute. Rise up above the bottom a few feet and scan for bubbles ... air bubbles are very reflective in ambient light, and will often be the most visible part of the diver. If you don't find your dive buddy after a minute, initiate a controlled ascent ... keeping yourself safe by making a slow (no more than 30 feet per minute) ascent to the surface. Once on the surface, remain there. If your dive buddy doesn't appear within a three to four minute window, summon help. DO NOT go back down on your own searching for your dive buddy ... chances are he will arrive at the surface a few seconds after you go back down. This can lead to a number of potential problems.

For those who dive in poor visibility, good buddy positioning and swimming slowly will reduce the possibility for buddy separation.

... Bob (Grateful Diver)

BamaCaveDiver
07-10-2007, 03:09 PM
Damn Bob, you have me wanting to take a class with you:p Very good information there.

rubber chicken
07-10-2007, 03:15 PM
Damn Bob, I wish some of my buddies had taken a class with you!:D

Grateful Diver
07-10-2007, 05:29 PM
Thanks ... hope some find my perspective on things useful.

... Bob (Grateful Diver)

Mountain Dog
07-10-2007, 10:03 PM
Grateful Diver-

In your first post you mentioned that there is a bit of math involved in developing safe diving plans. I think something that might be helpful in this discussion is if you could spell out the necessary formulas for divers to determine their sac rates and how to apply that number to varying tank sizes and dive profiles.

I have been doing these calculations for every one of my nearly 50 dives, and I'm starting to get a really good picture of my gas usage, which is quite necessary to take dive planning beyond the "go to the fire truck" stage.

I would provide the formulas, except I'm away from my dive books right now and would hate to publish an error. Besides, you're knowledge on this subject is legendary.

Mountain Dog

hbh2oguard
07-11-2007, 02:44 AM
also if you and your buddy is spearfishing you REALLY want to be side by side