Dive Phase Combat Training Class 222 San Diego Bay 2315 Hours

JJ and Olga were a dive pair. This was their first closed-circuit combat night training mission and they couldn’t see more than a few inches in front of their faces.

It was like being in a dirty loud washing machine with no lights. Sound travels much faster in water than it does in air, and they could hear the loud whine of a speed boat and the occasional whuga whug from the larger vessels with propellers the size of cars.

JJ’s worst fear was getting out in the open harbor channel and finding that a big tanker was overhead. They’d have to suck bottom to avoid being chopped up like fruit in a blender. And the bottom of San Diego Bay was pretty nasty.

Open circuit or SCUBA (Self Contained Breathing Apparatus) was one thing, the Draeger, German-built, was an entirely different style of diving. A hundred percent oxygen and no bubbles to give away your position.

The Draeger unit was surprisingly simple. It consisted of a small oxygen bottle, a canister filled with a chemical that absorbed CO2, and a double-hosed breathing tube that had a one-way check valve, all housed within a simple black chest-mounted container.

Inhale from the one-way hose and exhale out the other valve which scrubbed CO2 and put clean oxygen back into the closed-circuit rig. However, breathing pure O2 came with its own hazards.

Dive too deep and you get O2 toxicity. Anything deeper than 20 feet was a no-go. But stay above that depth and you could dive for over four hours. Long enough to swim into a harbor, plant a listening device or explosive, and get out undetected.

Tonight’s mock mission was to plant a magnetic mine on the target vessel and return to the pick-up point undetected.