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

The SRDD Sat Missions in Aquarius are going great. During the first five day mission, the dive team completed all their objectives successfully. The MK 16 MOD 1 UBAs were never intended for use as a Saturation Diving underwater breathing apparatus, however, here at Aquarius, and perhaps other opportunities in the future, a closed circuit rebreather provides the aquanauts extended excursion times without having to recharge SCUBA cylinder. The major difference is the breathing resistance. Closed circuit compared to open circuit as a noticeable increase in breathing resistance.

On these two missions, the SRDD divers are performing labor intensive tasks, which essentially challenge the rig’s performance to the normal demands of a deep sea diver. It quickly becomes obvious to the closed circuit diver that in order to complete the labor intensive tasks, the divers must “pace” their work. Completing tasks at a slower pace with detailed work procedures and thinking a procedure through can actually increase work productivity, by removing potential mistakes, causing rework, or by forgetting something due to being in a hurry. Task achievement and success is far more advanced when divers have a clear execution plan and good work habits.

Yesterday, the divers installed a new 300 gallon potable water tank on Aquarius’ baseplate, and replaced half a dozen large sacrificial zincs or anodes around the habitat’s mud mats and framework. Today the SRDD divers will be working jointly with the topside Navy and NURC divers to install a new boat mooring approximately 350′ from the Aquarius, as well as a permanent mount for a long term fish cam that will record fish counts over the coming months. The divers will use hydraulic powered coring tools to drill into the reef, and will then cement the mooring eye and camera mounting post to upgrade the Research Area’s capabilities. In keeping with diver safety and operational control, both divers will be using tethered communications and video from helmet cams back to Aquarius, which is then relayed to the surface support vessel moored just above the working divers.

The MK 16 rigs have worked well so far and have proven over the past couple of missions to be a viable option for future Aquarius aquanauts. After each dive, normally a 3-hour duration for the rebreather equipped SRDD divers, the rigs must be maintained; they require fresh CO2 absorbent, new O2 and diluent flasks, and battery/sensor checks. During the first excursion on the previous five day mission, one of the three O2 sensors aboard one rig failed during the dive, but the diver safely returned due to redundant sensors. Other than that one occurrence, the rigs have performed flawlessly out of Aquarius.

Yesterday, the divers installed a new 300 gallon potable water tank on Aquarius’ baseplate, and replaced half a dozen large sacrificial zincs or anodes around the habitat’s mud mats and framework. Today the SRDD divers will be working jointly with the topside Navy and NURC divers to install a new boat mooring approximately 350′ from the Aquarius, as well as a permanent mount for a long term “fish cam” that will record fish counts over the coming months. The divers will use hydraulic powered coring tools to drill into the reef, and will then cement the mooring eye and camera mounting post to upgrade the Research Area’s capabilities. In keeping with diver safety and operational control, both divers will be using tethered communications and video from “helmet cams” back to Aquarius, which is then relayed to the surface support vessel moored just above the working divers.