Mission & Project Info | NOAA’s Aquarius Undersea Laboratory
Mission Blog

Today is decompression day for us. Currently we are at 17 fsw and almost half way through our 16 ½ hour decompression from saturation. As with most all of our missions, whether you are topside or living in Aquarius, this mission has flown by. But unlike our normal missions, this one has explored the use of a different diving technology. During most missions we use SCUBA as the primary diving system for Aquanaut excursions, but other diving operations involve tethered “Hookah” and Superlite 17 dive helmets, connected to the wet porch via umbilicals.

The U.S. Navy Specialized Research Diving Detachment (SRDD) has introduced us another diving technology, closed circuit rebreathers, specifically the MK16. Although rebreathers have been around for quite a while, this is the first Aquarius mission where they have been used for Aquanaut excursions. One of this mission’s primary goals was for “us” (NURC) to learn the specific techniques of supporting rebreathers diving from a seafloor habitat, and from my perspective we have definitely accomplished that goal.

The potential use of rebreathers for making excursions from Aquarius has several advantages, which in turn could have a “ripple effect” on our mission operations. Since rebreathers scrub the carbon dioxide out of the diver’s exhaled gas and re-circulate it, as opposed to SCUBA, which just exhausts all the exhaled gas into the water, the volume of gas required to support diving operations is greatly reduced.

If future Aquarius missions used rebreathers instead of SCUBA for Aquanaut excursions, the size of the compressors on the LSB (Life Support Buoy) could be reduced. Reducing the compressor requirement would in turn reduce the amount of AC current needed to run them, thereby reducing the size of generators needed to supply power, allowing for a smaller LSB to be used for supporting Aquarius, and so on (i.e. the “ripple effect”). Although this mission is just a “first step” in that direction, the potential benefits of it and additional similar missions are easy to imagine.

The Navy divers on the first of these two SRDD missions bring a combined diving experience of over 64 years to this mission and it shows. All of these guys are “aces” in their field and have provided immense technical support and information about rebreathers to the Aquarius program.

I would like to thank Master Chief Master Diver Jim Knudson, Chief Gene Buijten, Chief Tim Ige and Chief Bill Dodd for the knowledge they have shared with me and fellow HabTech Craig Cooper during this mission.

It’s been an honor and a pleasure to saturate with you guys, thanks!