Manta Divers March, 2011 Making a Decent Descent
Imagine you and your buddy have arrived at your favorite dive site. You’ve planned your dive, agreeing on time, air limits and depth limits. You’ve completed a predive safety check and now you are ready to dive. You enter the water, deflate your BCD’s and drop. Right? This may be exactly the procedure that many divers follow when diving, but I believe that many divers dismiss the importance of using good technique in their descent. This step in the process that so many fail to spend much time thinking about can make a difference in the amount of enjoyment you derive from your dive.
Once you and your buddy are in the water, take a moment to look back at what your exit point will look like. Remember you will be looking in the opposite direction as you were when you entered and it may look quite different. If you are diving from a boat, especially if it is one of many that look similar, be sure you know the name of the boat and the dive operator you came with. It is good to be picked up after your dive, but even better if it is by the same boat that brought you.
Buddies should signal that they are ready to descend. With shoulders (and BC air dumps) pointing upward, pull down on your pull dump string on the right, if you have one, and your low pressure hose (if attached to the left dump valve). If properly weighted, you should start to descend slowly, more like a leaf, not a cannonball. Do not move your fins and arms. Exhale to further decrease your volume and thereby make yourself more negatively buoyant. Buddies must keep an eye on each other to avoid separation and to be available to one another if a problem should arise.
As you descend, keep your legs underneath you, either straightened or in a kneeling position to help you stay oriented and to allow continued release of air from your wetsuit and other places where it may be trapped. Continuously equalize your ears. If you are experiencing pain during your descent, you are going too fast.
A good way to monitor the rate of your descent is to use a down line for reference. As you go deeper, your exposure suit and any air you have in your BC will start to crush, decreasing your volume, making you increasingly negative. If left uncontrolled, your rate of descent will increase until you hit the bottom. If you notice that you are picking up speed, you can grab the line to stop you, or better, add short blasts of air into your BC to slow you. (Think the rockets the space modules use to make changes in their positions in space.) Remember to keep an eye on the line to prevent over inflation. The goal here is to slow the descent, not reverse it.
As you approach your maximum depth, be sure to be monitoring the environment below to assure you will stop before reaching the bottom. If you are adding bits of air as needed to slow your descent, when you reach your planned depth, you should be neutral. This technique has several benefits. First, it will conserve energy, especially if you have to ascend a bit to help your buddy, or equalize your ears. Stopping yourself from crashing into the bottom will preserve the visibility because you will not be disturbing any sand or silt. Lastly, it protects the environment from possible damage and supports the “No Touch” philosophy all conscientious divers follow.
If you’ve managed to execute your descent as described, you and your buddy are ready to explore the deep blue together, and in water that is the same clarity as it was before you arrived at the site. In addition, you will expend the least amount of effort and time to navigate due to your good buoyancy control. All facets of your dive training are important and good divers, always learning and looking for ways to improve, take time to reexamine all their skills and are always practicing to be the best they can be.
In Other News..............
Stop and check out the new Aqualung Dimension BC. This is an newer version of the Balance that includes the i3 inflation controller, and a more light-weight design.
Brush up on your skills before your next trip with a Scuba Review! Next sessions April 7 & 14 at 5PM.
Attention! As you know Team Manta is leaving the dreary Wisconsin Spring for the sun and water of Bonaire. Therefore, the shop will be closed March 14-18. Please plan ahead. Watch for reports on Manta Divers FB page.
Divemaster classes forming now. Here's your chance to join the ranks of the diving professionals. Call the shop for pricing and schedules.