|MOBY in the clear blue water at it’s mooring site off the island Lanai. Diver’s are used to service the buoy and for the deployment and recovery of the buoy.|
|MOBY Mooring schematic: A deep sea mooring buoy is tethered to the bottom (1200 meter) with 4 railroad wheels as an anchor. The MOBY optical buoy is connect to the watch mooring using a long tether.|
MOBY mooring site location: The buoy is moored 13 nm from Lanai in 1200 meters of water. The small inset shows a watch circle which is the result of the optical MOBY buoy circling it’s deep sea mooring.
|MOBY operations site: The site is in Honolulu Hawaii on the University of Hawaii’s Marine Center. The large tent is were the MOBY buoy is serviced, cleaned, reburbished and calibrated. MOBY team member offices are mobile labs seen around the tent.|
|MOBY inside the tent: After the bouy has been recovered from a deploymet. The buoy is power washed and then pushed inside the tent. Once in the tent the buoy is serviced, old components are replaced and calibrated.|
|Shark harasses MOBY diver: Oceanic Whitetip sharks sometime harrass the divers as they try and service MOBY.|
MOBY deployment Photos (top)
The Marine Optical Buoy (MOBY) is continuously moored 13 nm off the coast of Lania in 1200 meter of water. During prevailing trade wind conditions, this location is sheltered in the lee of the island, yet it is far enough offshore to minimize atmospheric perturbations associated with the island’s wake. There are two complete MOBY systems, one of which is moored and operational at any given time. The typical duration of a single MOBY deployment is between three and four months. During this period, the other MOBY is maintained and refurbished, and its MOS recalibrated to prepare it for deployment in relief of its alternate. The following photos are of a typical MOBY deployment.
Two ship board cranes are required to deploy MOBY, as well as, a small boat. Which is used to move the buoy away from the ship once it is in the water.
The crane simultaneously lifts both end of the buoy out of the cradles. Tag lines are used to stabilize the buoy as it is lowered into the water.
As the buoy nears the water the small boat begins to pull on the top of the buoy. This helps keep the buoy from hitting the cradles as it is lowered into the water.
The small boat pulls more to continue to swing the top of the buoy away from the ship.
Once the top is in the water the quick release is pulled so the buoy is no longer attached to the crane and the small boat pulls the buoy away.
The second crane will be released once the top of the buoy is far enough out.
Both cranes are released and the small boat pulls the buoy away from the ship.
In this case the buoy was deployed in the lee of Lanai and will be towed by the R/V KA’IMIKAI – O – KANALOA to the mooring 13 nm off of Lanai.
Normally it is preferred that MOBY is deployed at the mooring site. But in the case were the weather does not permit this, the buoy is deployed in the wind shadow of Lanai and towed to the mooring.
Mooring deployments (top)
|The deep sea mooring is deployed once a year. The mooring is used to tether the optical MOBY buoy and carries the meteorological sensors.|
|First the mooring is placed in the water. Tag line sare used to reduce the sway of the mooring as it is begin lifted into the water.|
|Once the mooring is safely in the water all the 1200 meters of line must be let out.|
|A winch is used to spool out the 1200 meters of line as he ship slowly moves away from the mooring buoy.|
|Right above the railroad wheels is the yellow hard hats. These are plastic protective covers for the glass balls inside which act a floats.|
|Directly below the hard hats is the acoustic release. The purpose of the acoustic release is that at the end of the years deployment, a signal is send to the acoustic release then separates from the anchor. The acoustic release, hard hat and all the line is brought to the surface and recovered. The hard hats and acoustic release is then reused to the deploy the mooring buoy. The railroad wheels are the last to go in. The mooring engineers have to calculate were to drop the railroad wheels so the pull of the mooring and all the line puts the mooring in the correct position.|