The beginning of the week was spend buttoning up the transceiver room which included organizing the transducer cables we pulled onto cable trays, pulling up the hydrophone cables through the conduits, and closing the Roxblox above the conduits.
Before cable organization
Cables being sorted/organized before being woven into the cable trays
After cables were organized into the cable trays on the ceiling. Also, some excellent final touches with zip ties above and below the transceivers
Cables organized and Roxblox (seen in blue at the base of the cables) closed
Installing Roxblox
Ethan at the top of the mast helping the surveyers collect point data
The second half of the week was crunch time to close up everything on the hull in order to be able to put the ship in the water on the 9th. The recieve array required us to play a maddening game of tetris with eighty pound blocks and five ice windows because the windows were stepped in respect to one another. In addition, all of the spacers that accepted the bolts to secure the ice windows were cockeyed for reasons that could only be surmised but were certainly the work of the Seward gods testing us in our final hour. Nevertheless, we were up to the task and dodged the problem by reducing the number of bolts securing the ice windows. We caught a break with the Tx array and installed, dressed, and torqued the ice windows with no problems. With that, the work under the hull was completed. The next day, the shipyard broke the ice on the rails and moved the ship into position to be lowered. All went well, and the Sikuliaq once again was in the water with only minimal leakage around some pipes. Since there was very little ballast and fuel in her, the ship was pushed across the bay to the ferry by barges.
Tx array before ice windows installed. The blue color is due to a thin layer of anti-fouling paint added to the transducer faces.
Three techs contemplating the Rx array. The white square in the hull (top left) is the Topas, a sub-bottom profiler which sends down low-frequency pulses that can penetrate into the seafloor. This allows scientist to see the different layers of sediment and rock in order to find features like ancient lakes. The trade off for sending out low-frequency pulses is that the resolution of the image you generate is lower. The round yellow ADCP in the hull (top middle) sends out higher frequency pulses which is less penetrating but the resolution is much finer. With enough resolution, scientist can detect plankton in the water column!
Raising ice windows on the Tx array. Ice windows are put into place for, as their name suggests, protecting the transducer faces from ice. The Sikuliaq often works in the Arctic and this buffer is a very important safety mechanism.
Sikuliaq riding high out of the water, being barged into place
Shipyard survivors 🙂
Thanks for reading,
Sarah
