07/22/2014
Tuesday the crew of RPM, Jack, Emily and I went out on our first mission with the underwater sector scan sonar equipment. Once we arrived on our site, our captain held us above our wreck using a a dynamic positioning system (DP), which keeps the ship in the same position, kind of hoovering above our site; the captain inputs our latitude and longitude and a bearing into the computer and then the computer will calculate and then adjust the thrusters and shafts to work in-sync to keep us in the same position. Then, Cameron, our instructor went over how to build the sector scan sonar tripod. Once our sonar was put together and all of the attachments were in place we learned how to run the cable out and connect it to the transducer. After that, we helped with out first deployment. Gerry, one of the engineer's operated the crane which lifted up the sector scan, and submerged it into the water, very slowly. Every 10 meters the guys would strap a ziptie to keep the steel cable and the computer cable together. Once the tripod landed firmly onto the seafloor (at roughly 76 meters) the lab crew would call out to the deployment crew to stop the decent. The lab crew had a computer monitor with the sonar readings, which would determine the bottom return. The lab crew would take several surveys of the sea floor, and then move a few meters at time to create a mosaic of the sea floor. See below for pictures.
but first, let me take a selfie! ;)
Shot 1. Morgan Bode pictured, with sector scanner in the background.
Morgan Bode. GoPro
Shot 2. Cameron shows us where to get the parts to build our sector scanner.
photo credit: Jack Seubert
Shot 3. Emily and Morgan are clipping the support legs together, forming the structure of the tripod, that holds the transducer in the middle.
photo credit: Jack Seubert.
Shot 4. Us in our cute life jackets! :) Cameron is handing out the clips to secure everything together.
photo credit: Jack Seubert
Shot 5. Morgan assists Emily while she clips the weighted shotput under the transducer, to help it sink faster.
photo credit: Jack Seubert
Shot 6. Emily connecting a cord to the transducer box.
photo credit: Jack Seubert
Shot 7. Gerry, operating the crane, and Richard directing the sector scan over the gunnel.
photo credit: Jack Seubert
Shot 8. The sector scan beginning its decent into the sea.
photo credit: Jack Seubert
Shot 9. Morgan is demonstrating how to unravel the cable for deployment.
photo credit: Jack Seubert
Shot 10. The monitor with a glance at the survey data. The "bumps" or lighter colored dots, are called "target of interest".
photo credit: Jack Seubert
Shot 11. These are day shapes. Ideally this particular pattern is a sphere or circle, over a diamond, over a sphere. Which means restricted in maneuverability. Dayshapes help other vessel, that are nearby know to stay away and far out of our way, because we are operating and we cannot move once we have our sector scanner 250 ft on the seafloor.
photo credit: Jack Seubert
Shot 12. Emily and Morgan organize the cable in an orderly and safely fashion.
photo credit: Jack Seubert
Shot 13. On the left is Cameron and Richard. They are taking in the cable, and undoing each ziptie as Gerry brings up the scanner with the crane. The cable then gets passed from Richard, to Emily, and then on to Morgan as they coil up the cable.
photo credit: Jack Seubert
Shot 14. Zeus stopped by for a bit. :) The storm that ran us off.
photo credit: Jack Seubert
Shot 15 (left) 16 (right).
A waterspout forms on our starboard side. We kicked it up a few knots and got into port real quick!
photo credit: Jack Seubert
All of the above were photos from our first day at the Rodon Amphora site.
We did go back out to the wreck on 07/23/2014 and finished 17 drop sites with the sector scan, however, only videos were taken, so please review the youtube site to see everything in action!
https://www.youtube.com/channel/UCKV9mHN9WJU-IX-NQOHCQ4Q
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