Learning Buoyancy Control

 

Many divers strive for good buoyancy control.  Doing so enables a diver in full gear to effortlessly hover and efficiently swim through the water.  The graphic on the science of buoyancy indicates a number of factors that affect buoyancy.

I know instructors who slightly “overweight” their open water students to eliminate the up and down movement that many divers experience when first learning to dive.  Divers may equate being slightly “negative” to sink with good technique.  This practice results in divers dragging themselves along the bottom colliding with terrain as they move along or expending more effort than necessary. They figure adding a bit of air to the buoyancy compensator to “compensate” for a couple of pounds of excess weight is easier. 

Learning Buoyancy

Divers learn a rudimentary buoyancy check technique in the open water class.  Wearing full gear in the water, with the regulator in their mouth, the diver vents all the air out of the buoyancy compensator device (BCD), while slowly exhaling.  A properly weighted diver will sink ever so slightly ending up with the eyes at water level and rise to the starting point when inhaling.  If the diver sinks beyond that point, weight is reduced.  If the diver cannot sink to that point, additional weight is needed. 

This approach yields an approximate neutral buoyancy weight for the gear the diver wears during the check.  Different wetsuits, tanks, and other gear have unique buoyancy characteristics.  In the early 2010’s, my gear configuration went through a series of changes, new drysuit, undergarment, and backplate and wing BCD.  Each addition required changes to the weight I used and affected my underwater streamlining.  It took a couple of dives to make everything just right. 

But Wait, There’s More

Divers can fine tune their buoyancy skills after open water certification.  Taking a so-called “peak performance buoyancy “ specialty course provides additional skills.  As the PADI course description states

Excellent buoyancy control is what defines skilled scuba divers. You've seen them underwater. They glide effortlessly, use less air and ascend, descend or hover almost as if by thought. They more easily observe aquatic life without disturbing their surroundings. You can achieve this, too. The PADI Peak Performance Buoyancy Specialty course improves the buoyancy skills you learned as a new diver and elevates them to the next level.

Why these concepts and techniques are an “add on” rather than part of the open water certification course perplexes me. 

My Experience Observing  Peak Performance Buoyancy

I did have a chance to do the in-water skills portion of the course when my dive buddy, Luke, completed the Peak Performance Buoyancy session in Kona, Hawaii in 2018.  At the time, Luke had completed about 10 dives.  I tagged along to help balance the workload between the dive guides and instructors on board the Kona Diving Company boat.  In doing so, I went through the skills as an active participant rather than as a passive observer.

Luke’s PPB required that he complete the on-line e-learning module and two open water dives.  First, our instructor, Hailey, checked that Luke was neutrally buoyant at the surface using the tried and true method described above.  For Luke, 18 pounds of weight did the trick.

Hailey then put Luke through a series of exercises.  She placed three weight pouches on the sandy bottom containing one pound, three pounds, and five pounds.  Starting with one pound, she directed him to approach and pick up the pouch without disturbing the bottom or sculling with the hands.  After a few tries, Luke mastered snatching the one pound pouch.  The exercise progressed to retrieving the three pound pouch and finally to the five pound pouch.  

During the three-minute stop at the end of the dive, Hailey asks Luke to hover at 15 feet both horizontally and vertically.

As the dives progressed, Luke’s skill increased.  The ultimate test of mastery of the skill is to hold the lotus position while suspended mid-water.  Luke held the position for 80 seconds--a commendable accomplishment.

In between exercises as we toured we encountered black triggerfish, butterfly fish, lots of jacks (a symbol of masculinity in the Hawaiian culture), and a white-mouthed eel.  We saw a milkfish, usually a diver-skittish species, and a filefish consuming a jellyfish.  When it was done, it nibbled on Luke’s head.  I guess the filefish confused Luke with a jellyfish with his newly found buoyancy control.

All kidding aside, after a skill is learned it takes practice in order to be ingrained in a diver's technique.  After a few dives, Luke had mastered the art of maintaining neutral buoyancy throught the entire dive.