2001 Sea Tiger I

I recently realized that for the types of dives that I've been doing and also progressing towards, a closed circuit rebreather would provide substantial benefits in the areas of logistics, gear configuration and safety over open circuit scuba. I evaluated several different models via research and discussions with divers who dived them, and selected a Mk-15 due to its simplicity of operation and decades of proven reliability with the U.S. Navy. My Mk-15 was rebuilt by Kevin "The Dude" Juergensen to include several enhancements, such as completely updated electronics and a whitey valve for switching between onboard and offboard gas supplies. The Mk-15 can be thought of as an "open architecture" rebreather, with various third parties making improvements and customized components.

Closed circuit rebreathers are extremely dangerous in the hands of the untrained, so I signed up for a 10-day trip to Hawaii to learn the Mk-15 with Joe Dituri, who is one of the very, very few people in the world that are currently actively training people outside the Navy on the Mk-15 and its variants (there's like 3 or 4 of them).

The following pictures (all images from video) are from two of our training dives, to a small Japanese freighter, the Sea Tiger. Or maybe that's the Sea Tiger Maru. ;-) These took place on February 28th and March 1st, 2001. Background image: surfing the Bonzai Pipeline on the North Shore of Oahu.

This is my new Mk-15 with the scrubber canister exposed. In the center of it you can see the O2 sensor array. There are two white compressed gas spheres, one for oxygen and on for the diluent gas. Metalworking expert Enrique Alvarez made me a custom stainless backplate for the unit, that enabled me to use my exact same harness that I do when I dive with doubles. I also modified an old DiveRite 65 lb. classic wing by gromitting holes in the center to allow water passage into the holes in the Mk-15 chassis below the counterlung (which is on the underside of the center section, below the scubber).
	We arrive at the dive site, just off Waikiki. The Diamond Head volcano is on the right. Joey ties into one of the two moorings on the wreck. He is one very busy guy.... he's a naval officer and project manager responsible for overhauling US Navy ships at Pearl Harbor, has his own marine salvage / hyperbarics / diving company, and is vice president of IANTD.
I swim over the bow of the wreck.
	This is looking at the bridge. The wreck is almost completely intact.
Joey, diving a Cis-Lunar Mk-5, takes out his light to go look around inside.
	Inside the Bridge, I show off the backlit display of the new Smithers-Juergensen electronics.
Dusting off and looking at the bridge equipment!
	Looking forward from just outside the bridge.
Here I'm in front of the stack, just behind the forward superstructure.
	Some rooms in a small deckhouse.