In the 60s when I began diving instruction the class equipment was an eclectic assortment of double hose regulators, a few single hose jobs, 33, 50 and 72 cf steel tanks with I valves or J valves and most rigged on a military harness which used no plate at all, the tank was the structural member.
It was suggested that a diver could experience no-BC diving simply by not using their BC. LOL, no, just no. If a diver really wants to learn no-BC diving methods then again, they must forgo all of the modern encumbrances, no dual regulators, no pony bottles, no steel doubles plate, no STAs, no padding, no octopus. A tank (aluminum 63/80/steel LP72), a military harness or Oxy fabric type Ultralite plate or a simple plastic blow molded plate, a single regulator and an SPG. Use buoyant or neutral fins like the modern Scubapro Go-Sports and a low or mid-volume mask and a maximum 3/2 suit and preferably none if can be tolerated. The USA made and NLA Rubatex nitrogen blown neoprene suits we used did not compress as much as the modern day imported hyper-stretch stuff and it was warmer too. My 3/16 suit (5mm) did undergo an initial compression thus the need to
swim down but would remain quite buoyant even at 60 feet thus allowing me to
swim around and when with the air depleted from my LP72 remained sufficiently buoyant at the end of the dive to assist me to
swim back up.
But, the closest we can come to no-BC diving is a Hog rigged (meaning a simple one piece no padding harness) VDH/Freedom/Oxy textile plate with a minimal wing of 18-23 pounds of lift. And I would hate to have to float for hours in such a rig. I carry a DSMB and when I float for "hours" (only sort of happened once) I inflated my DSMB and used it as counter flotation like a big pool noodle under my arms and across my chest. Otherwise trying to lift my head up out of the water sufficient to breath sans regulator was difficult and results in face planting and leg cramps from trying to resist the forward roll. In the day, when needed to float for hours, most of us, when exploring further offshore, had a Mae West vest similar to a modern snorkel vest to inflate if needed on the surface. And unlike modern divers who tow a small dive flag float when shore diving, the pre-BC shore diver would often have a more substantial surface float, often a truck inner tube even with a floor or a surf/dive board or other means of significant flotation. And again, most were good swimmers.
This is a horrible picture from about 6 years ago but here I am returning from the deeper ledge (a very long swim) at Fort Lauderdale Commercial Pier. I have no BC, I have no vest, just a rash guard and swimsuit. I have my Voit 50 Fathom DH, a banjo bolt with an SPG, Mares full foot fins and a surface float with flag and GPS. Nowadays I would also have my cell phone and a PLB I suppose and I might use my inflatible SUP for surface support and egress. (I have done this area numerous times using my SOT kayak).
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That distance is 1.36 miles out and then back the same, swimming the whole way with no BC or even a vest of any sort. It took me over four hours. I was then 62 years old. And it cannot be done?
You might note that I am on my snorkel but it is stuck under the mask strap and the keeper is free. That is because I dislike snorkels and just had it tucked into my swimsuit out of the way during the dive but used it to assist my surface swim out and back. This was one of my last swimming only dives this far out here as I was accompanied by a bull shark on the way in and it just seems to me that such sharks have become more common in this area, not sure. Plus I am older and do not feel like swimming that far when I can use my kayak and go much further, faster and safer.
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