It’s been approximately a month since I left for San Diego. Since then I have completed a mooring deployment cruise and a sediment coring/imaging cruise. I must say it’s been a busy month and It feels rather strange to be back on shore.
While I am back I will have to head to our Newport storage facility to pick up some items for my next cruise (spare PMI grips, sensors, etc) and I will continue to try and solve my Triaxus problem.
Brief update since my Shakedown cruise on the Healy.
– Successfully completed the full inventory on all of the Triaxus boxes that OSU received from Moss Landing. Meaning that I will be able to start work on the rebuild during my next period of shore leave. Still not 100% sure where to even start on this project since we appear to have a lot of spare and broken parts. As well as the fact the Triaxus was supposedly customized by the Applied Physics Lab at the University of Washington….and the documentation is missing. It’s almost like buying a puzzle at the Goodwill and discovering you are missing the crucial boarder pieces. Luckily I still have the original MacArtney documentation as well as access to some great resources if I need to ask questions.
-Mooring deployment cruise. Completed a week long mooring deployment cruise for a Naval research group. Their custom “Quadpods” and ADCP/Temperature moorings will be used to monitor sediment transport along the seabed. Overall the cruise went well, we finished all the deployments in two days.
-Coring cruise. As of 0800 this morning we shipped out of San Francisco to begin a sediment coring cruise with a private research group based out of Washington. This seems like it will be an interesting cruise, albeit a lot of work due to the 24hr ops. Since the Oceanus only runs one technician generally, true 24 hr ops are not really possibly. However for this cruise one of the science technicians will spilt a 12hr shift with our marine technician (noon-midnight, midnight-noon) and I will be running from 6am-6pm in order to maintain clear communications between our science party and crew.
Been awhile since my last detailed post, but time flies and I’ve been way too busy to even muster the urge to type anything useful.
This last week I had the fortune to work aboard the USCGC Healy for a 4 day shakedown cruise. The goal of a shakedown cruise is to get all of the science and technical aspects working since the ship had been sitting essentially unused for a few months. Dusting off the cobwebs on computer based systems are always fun because they always seem to turn on with new issues. Overall our cruise went well, with the main exception being the 4 hour delay due to engine failure before we left the dock. Our main issues revolved around the Met System that displays the flow through information, the multibeam, and the CTD.
On the cruise I learned and practiced many useful techniques. Its amazing how every technician you meet has a different way of doing things, a prime example being CTD terminations. On the shakedown cruise my OSU tech coworker and I got to work with some awesome Scripps technicians since the Healy shipboard tech support group is made up of a collaboration of OSU and Scripps (STARC) and the Coast Guard’s MSTs and ESUs. Overall it was a great experience.
As for present day. I am currently back in Corvallis Oregon working in our office space. I am still inventorying the multiple boxes of Triaxus related gear before I can even think about piecing it together. However I only have till Sunday before I fly off to meet the R/V Oceanus for a month at sea. I am hoping my coworker starts to feel better otherwise I may be the lead marine tech running this upcoming cruise. It would be entertaining and fun to run the cruise for sure, but I still have to read over the cruise plan and expected science to be completed.
During my 6-month internship I will be working on rebuilding a MacArtney Trixaxus. I am absolutly thrilled to have the oppertunity to help my ship regain an extremely useful piece of equipment, however I am also somewhat terrified as all of those boxes contain random parts, cables, and electronics that I don’t quite undersatnd at this point.
The above image was taken on the R/V Point Sur and stolen from Wikipedia.
As for what a Triaxus is….I’ll leave the description to the MacArtney website article:
“ Adding a new dimension to towed vehicles, the TRIAXUS is the natural step forward from the existing 2D towed vehicle technology to a true 3D towfish. The TRIAXUS uses state of the art computer technology and fibre optic telemetry for vehicle and sensor communication.
The TRIAXUS features flaps for vertical as well as lateral control. A powerful industrial PC controls the vehicle based on input from the onboard vehicle control sensors according to the preprogrammed flight path.
The TRIAXUS is developed for high-speed oceanographic data acquisition work, and is designed to undulate between 1 and 350 metres*. Lateral offsets of up to 80 metres to either side of the ship is possible, enabling the vertical profiling to be carried out in an undisturbed water column.
Towing speed* between 1 and 10 knots and vertical speed* of up to 1 metre per second are possible. The TRIAXUS has been designed using the latest carbon fibre moulding technologies and the Danish Maritime Institute (DMI) has supplied the hydrodynamic design. The embedded telemetry system is based on the successful NEXUS fibre optic multiplexer system, allowing interface of up to 9 additional sensor packages using the Plug and Play principle.”
As an intern on the R/V Oceanus I have had the pleasure of watching experienced marine technicians not only work on deck but also work on cruise planning logistics in the office. On my last internship I never had the ability to see how cruises were actually planned and how marine technicians worked through logistical issues with the science party. What I have witnessed is both amazing and slightly daunting to a new technician. A constant flow of emails with questions and concerns are often waiting for us each morning, and it can be frustrating as you must research whether or not a scientist’s supplied gear will work on your vessel. If the gear the science party wants is not personally supplied then you must look into the different UNOLS equipment pools. Two of the pools I am quickly coming familiar with are NORCOR operated by OSU and the West Coast Winch Pool operated by Scripps. NORCOR primarily offers coring and dredging gear for the UNOLS fleet while the West Coast Winch Pool offers various winches and spoolers.
While planning a cruise a marine technician and chief scientist must assess what sort of winch and wire, if any, are needed for their operations. Currently the Oceanus is outfitted with two small starboard winches (DESH-5 and COM-15 models) and one stern winch (Dynacon HT). Generally there are four standard categories of oceanographic cables, trawl, hydrographic, electro-mechanical/CTD, and fiber optic. Below is a chart of the general characteristics:
Trawl
Hydro
E-M/CTD
Fiber Optic
Size
9/16”
1/4″
.322”
.681”
Construction
3 x 19 galv.
3 x 19 galv.
2 armor galv.
3 armor galv.
R.B.S
32,500 lbs.
6,750 lbs.
11,600 lbs.
46,000 lbs.
Yield
24,375 lbs.
5,063 lbs.
5,000 lbs.
—
2% Yield
28,600 lbs.
5,900 lbs.
—
—
S.W.L
14,300 lbs.
2,950 lbs.
4,500 lbs.
14,000 lbs.
Below are three figures showing the internal slice of the Trawl, E-M, and Fiber Optic wires. I was unable to find a diagram of the 1/4 “ Hydrographic wire.
Trawl wire and hydrographic wire are both generally used on the aft winch as a means of deploying and/or towing various scientific insturments. Trawl wire (9/16″) is used for heavier objects due to it’s size and breaking strength while hydrographic wire (1/4″) is used for smaller applications.
Figure 1. Construction diagram of the 9/16” 3 x 19 Trawl Wire and the 1/4″ 3 x 19 hydrographic wire. All UNOLS 3×19 wire rope are torque balanced, meaning that the rope resists rotation and on the sudden release of the load will not kink or form loops. They also have a higher strength to weight ratio when compared to conventional 6-strand rope.
The .322″ E-M cable is used for various insturments, most commonly a CTD (conductivity, temperature, depth sensor), as its internal electrical conductors, made of copper, allows data transmission to happen between an insturments and its deck box. This allows for functions such as real time variable profiles (exp: CTD display of temperature, salinity, depth) as well as triggering an insutrment to open/close (exp: closing of a niskan bottle on a rosette).
Figure 2. Construction diagram of the .322” Electro-mechanical/CTD cable
The .681″ Fiber optic cable is simialr in a way to the EM cable due to the fact it is also used to trasmit data back and forth from an insturment to a deck box with the exception that it uses thin strands of coated glass fibers instead of copper conductors. To transmit data information is digitized and coded onto light pulses whcih travel along the glass fiber at the speed of light. Once it reaches it’s destination a decoder coverts the information back into a useable format. Due to this process it is much more effiecent then copper conductors. A notable example of its use is in the deployment of ROV’s such as ROV Jason on the WHOI ships. These fiber optic cables allow the ship to send commands to Jason as well as recieve the data and images that the ROV captures.
Figure 3. Construction diagram of the .681” Fiber Optic cable
Currently the R/V Oceanus only has two types of wire on board, the .322” E-M and the 9/16” 3×9 Trawl wire. However both .680 E-M and .681 Fiber optic cables are available if requested.
Breaking Loads
When it comes to working with wire two of the most important considerations to keep in mind are breaking loads and the safe working load. Breaking loads are separated into three categories (definitions are from the UNOLS Appendix A):
-Nominal Breaking Load (NBL): Manufacturer’s minimum published breaking load for a rope or cable.
-Tested Breaking Load (TBL): The actual load required to pull a tension member to destruction as determined by testing.
-Assigned Breaking Load (ABL): Will be the lowest of the Nominal Breaking Load and Tested Breaking Load. In practice, ABL = NBL unless testing shows the TBL < NBL.
The Safe Working Load is the maximum load that is allowed to be supported during normal operation. It is derived from the Able Working load (ABL) and a Factor of Safety (FS), the Factor of Safety is selected by the operator based on rules set by the UNOLS Appendix A. So: SWL = AWL / FS
In order to determine the Test Breaking Load (TBL) of a wire the UNOLS ship is required to send a sample of their wire to the WHOI Wire pool. There they will conduct a tensile test using either fixed ends or one end free to rotate (depending on the requirments of the wire). After the sample wire is broken the ship will recieve a certifiation of testing report showing the breaking features of the wire. Below is an example test certification:
Depending on the results of the break testing and the Factor of Safety selected for the wire, testing could be required every 6 month, annually, or every 2 years.
Overall this has probably been a very technical and in some ways confusing blog post. However this is the nature of the marine technician buisness. Understanding the basic concepts of the tools given to you, as well as the guidelines setforth by the fleet and home institutions (UNOLS Appendix A) can allow you to be a better safer technician. Plus…where’s the fun in all of this stuff if it wasn’t a little confusing? Life would be boring if it was always so straightforward.
Next Post: Understanding Wire and Rope (Part 2) – Rope
Date: 3/25/2015
Time: 20:58
Location: Corvallis, Oregon
Quick introduction
Greetings to the few people that will probably glance over this blog post, my name is Sonia Brugger and I am the 2015 6-month MATE intern. A brief background about myself: I graduated from the University of Washington in June 2014 with a degree in Oceanography as well as Aquatic Fishery Sciences. I have spent time on the R/V Thompson, Barnes, and New Horizon as well as having had the pleasure of spending July-October of 2014 on the R/V Savannah for my short term MATE internship. Overall the majority of my past cruise experiences have been focused around biological and physical oceanography.
Log
It has been four days since I officially started my internship. The first two days consisted of checking into my housing as well as meeting the new hire for the OSU Marine Tech pool. On Sunday Rob (the new hire) and I drove down to Newport, OR where the R/V Oceanus is stationed to meet the crew and tour the ship.
Monday was my first day of actual work. Since the ship was leaving for a 4-day cruise starting Tuesday morning I spent a short portion of my day helping load gear, which consisted of a large amount of geological sampling instruments (grab sampler, gravity/piston corer, box corer). With the loading completed I learned how to terminate the .322 CTD wire and calibrated the tension sensor through load testing. There were also other small projects that I helped the other techs with such as installing sensors to the CTD package, putting up a bench in the wetlab for the science party, and troubleshooting the fluorometer. Overall it was a long day, around 14hours including the hour-long drive from our tech shop in Corvallis to the dock in Newport.
Today was relatively tame compared to Monday. Rob and I drove to Newport in the morning to bring over some paperwork and help the tech Johna with any last minute things before her cruise left. Overall there wasn’t much to finish up other then making sure the cables on the CTD package were ziptied and we didn’t leave any unnecessary gear on the ship. Afterwards we headed back to Corvallis to meet with the OOI (Ocean Observatories Initiative) group that would be sailing with us next week. We sat in a cruise plan meeting and got to check out all of their buoys/moorings. It was pretty exciting and yet rather unnerving to know that will be my first cruise as a marine technician on the R/V Oceanus. The OOI project is one of the biggest and probably could be considered as one of the most important projects currently going on in the oceanography community. The buoys that we will be deploying and retrieving are some of the largest ones built which makes them extremely difficult in a deck operation standpoint. As marine technicians for this project we will have to get one of our techs trained in the operation of a special heavy lifting winch that will be installed on the ship Saturday and is the only thing capable of working with the massive equipment. Overall it has been a thrilling start to my internship. I’ve already learned a lot of useful things and met some great people.
One week later and I still find remnants of my internship in my pockets. A shackle pin, zip ties, soldering wire and lots of used electrical tape. Looking back it all happened so fast but it was an amazing experience.
On September 5th at 0400 the silence was broken by the sound of the main engine that was just ignited. Half an hour later I get up excited about the work we had to do but sad since it was my last day on the Oceanus. I have been fortunate to squeeze in one last day cruise before the end of my internship, the objective being to retrieve two science buoys and two gliders.
Mooring work, I believe, is one of the most exciting things the marine tech gets to do. It takes focus, vigilance and excellent communication skills. You have to be aware of your surroundings at all times, ready to foresee what might go wrong.
About half an hour before the retrieval we had a meeting on the bridge with the captain and all the people involved. The head marine tech, Dave, went through each step of the operation making sure that the captain, whose primary concern is safety, agrees all the way through. If not, adjustments are made in the sequence of events or methods used.
After that, we went down to the aft deck where Dave assigned us specific tasks; who is going to be tagging which of the three lines, who is going to be tending each one, who is going to operate the crane, the A-frame, winch, and capstan, and who is going to strap down the buoy on deck.
What I find most amazing is that eleven people managed to work in unison on our small aft deck through a web of lines and trip hazards, and safely secured a 700 lb buoy that was hanging from the crane, 12 feet in the air and swinging with the swell.
Which brings me to the most important aspect of my internship; the people I had the opportunity to meet and work with. From our stewards Joy and Sean that always prepared fabulous food, the Able Bodies: Doug, Mark, and Patrick who taught me how to work safely on deck, the engineers: Chip, Jay Bart and Dave, who kept me alive in the transducer well and provided all their technical knowledge, the mates: Tony and Todd and captain Jeff Crews who welcomed me onboard and let me hang out on the bridge.
Of course I cannot thank enough my mentors and marine techs Johna, Dave and Toby who were always there to answer my questions and provide all the insights of their profession. I also feel fortunate to have met the science groups from WHOI, Scripps, Oregon State University, the University of South Florida and the University of Washington, who gave me the unique opportunity to learn about ocean bottom seismometers, moorings, oceanographic buoys and internal waves.
Lastly I would like to thank Tami Lunsford and Nandita Sarkar from the MATE program that made this experience happen and arranging for me to work with the R/V Oceanus group.
This past week we have been tied to the dock doing various repairs and getting ready for the next cruise. The crew sanding and painting in the wet lab, the mechanics welding in the galley, the marine techs opening and cleaning all hardware in electronic racks, and the engineers installing a flow through system pump in the engine room.
But last Tuesday was not an ordinary workday. After lunch Jonha, the marine technician, and I climbed through a hatch below the main deck and down a 16 foot narrow tube into a chamber the size of a Volkswagen Beetle.
After making sure we had all the tools we needed, we established radio contact with Chip, the engineer, and told him to close the door and start pressurizing. Air started coming through the vents and our ears started popping as if we were scuba diving. After 30 minutes of swallowing to equalize we reached seven psi. Only then we began to remove the bolts from a thick steel plate located at the bottom of the ship. Sixteen bolts later, I lift up the plate to see the ocean beneath me as still as if it was a bowl of water.
The objective of all this was to replace the two plates with Acoustic Doppler Current Profiler (ADCP) transducers that emit high frequency pulses of sound that scatter off moving particles in the ocean. From the change in transmitted and received frequency we can determine current velocity.
These transducers look like one-inch thick steel 19th century top hats with sensitive instruments inside. Securing them into their exact position in this small space was a challenge to say the least. It took us three hours to install them both, check for leaks, repeat, add more washers and check again.
The simple physics behind the reason why we didn’t sink the ship by opening a hole in the hull is that the pressure of the water at that depth is less or equivalent to the pressure of air in our chamber, so ideally there is not fluid movement either way.
On one occasion the waterline started rising so we radioed the engineer above to increase the pressure and the water started going down. What we found out later is that every time we made a seal between the hull and the transducer the air pressure jumped up to 9 psi, so the engineers had to immediately turn off the intake and open the valves to release air. Big thanks to Chip and Don for standing by for three hours monitoring the gauges. Overall, it was an amazing experience.
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