Argg Matey’s,
Thanks for tuning back into the adventures aboard the R/V Marcus Langseth. This week has been full of surprises. From blue whales to hydraulic malfunctions; join me as I retell last week’s adventure.
First our OBS (Pictured) recovery hit a few snags. We had one that was unable to communicate with the ship and couldn’t be recovered (we will try again next week). Another OBS had an O-ring fail which caused the logger compartment to flood and react with the lithium battery. This caused an explosion/melting of the logger and part of the containment structure. The data for this OBS was lost. After the recoveries we deployed the streamer which is a 8km array of hydrophones spaced 25 meters apart. We control the depth of this streamer (between 11-13 meters) with 29 “birds” or radio operated diving modules. They are equipped with “wings” or flukes which can be changed for the desired depth. Each “bird” has a pressure transducer used to measure its depth below the sea surface. We simply tell the birds to dive to 12 meters and they adjust their flukes till they are there and then level out. We also mounted acoustics on the streamer one at the beginning and one at the end to give us range and bearing of the streamer.
After we finished with the streamer I hoped down to the gun deck put on my harness and we deployed the guns (which requires hanging over the back of the ship getting soaked by waves running up the slip way and it always seems to be raining when we put the guns out).
The idea behind the streamer and gun array is to measure the two way travel time (streamer) of the reflected/refracted sound waves (guns).
But nothing ever goes as planned. While deploying the streamer we blew a hydraulic line. After quickly dealing with the leak and isolating the line, we came up with some clever ways of using winches on other hydraulic systems to finish deploying the streamer. Seeing and being part of a crew who can work together so quickly and efficiently to overcome un-foreseen problems was inspiring.
One thing about science/ship life is it gets very hectic and busy then….nothing. You just sit around for 12 hours doing your logs and monitoring instruments. Maybe some ship maintance like cutting angle iron for building shelving or re-greasing machinery. This is how it’s been the past three days. Except for a few blue whale sightings that we are required to shut down the guns for, it has been quiet. This is good for science but boring for us lol.
I am sure things will get more interesting soon they always do!
Till next time
– C