Join me, Dana Yoerger on my first journey aboard R/VFalkor to Loihi Seamount. With over 70 oceanographic expeditions under my belt, I still get excited for the unknown adventure that awaits mapping underwater seamounts and volcanoes, who knows what discovery is just around the corner.
July 1st, 2014
We had a good dive with Sentry at the Shinkai Deep site (~4700 depth) last night, doing multibeam, sidescan, and photos. Sentry behaved quite well and the launch was very smooth. Recovery was probably our most challenging to date, with wind and swells a bit higher than before. Ship handling and deck work all went very well. The multibeam map came out very nice, and our data pipeline made short work of the processing tasks.
Two of the vehicles science sensors, Eh and optical backscatter, were not working. We knew that before we launched but Brian the chief scientist on the cruise, and I decided we should go in without them working. While Sentry was on deck, we diagnosed the problems (corroded electrical connectors on both) which were repaired. No doubt we made the right call as those repairs took some time. Fortunately, we had all the needed spares on board. We are hoping for the best from those sensors on Sentry’s 4th dive which started just before lunch.
We are fighting some problems with the networking to the vehicle, which has meant we have had delays while we offload data and charge the vehicle’s batteries. We had to delay our launch today to get those tasks done. We will have a better plan for our next on-deck period.
The photos from the last Sentry dive have kept Brian pretty busy. Entertained as well, I think. He has been able to relocate targets from his previous Jason dives and found plenty of new microbial sites, as well as the inevitable trash. Our navigation corresponds very well to the Jason coordinates for the targets, 10-20m in most cases. This is consistent with the performance we expect from our USBL navigation system used on both cruises.
Arne, one of our geochemists, landed a nice mahi-mahi today. His enthusiasm for fishing is exceeded only by his excitement about his scientific work. A beautiful (and no doubt tasty) fish.
Yours truly from the Falkor,
Dana Yoerger
June 27th, 2014
We launched about 7:30 a.m. local. We had been aiming for 6:00 a.m., but we had a delay with getting our topside navigation working. Leighton Rolley, our cruise coordinator and marine technician, had the ship make a few multibeam lines to fill the time. We got our problem squared away and the rest of the launch went smoothly. Winds are about 12 knots and the seas mild. Sentry and ship teamwork is excellent. We have all our displays plumbed around the ship using Falkor’s distribution system.
Sentry descended normally to the seafloor at about 5000 m. We had a decent USBL tracking, it’s a bit noisy but no complaints there. We have not heard any acoustic message after about 4000 m depth, but we think the vehicle is hearing our commands. If we get any replies at all we will be happy.
Today’s dive has a high-altitude multibeam run over “the bumps”, then side scan and photos over some known microbial mat targets to the west. Judging by the USBL fixes, all is going well, the first turn was nearly spot-on the desired point. We are hoping for a long run.
Life aboard Falkor remains very good. The crew could not be more helpful. The ship is very quiet, and the food is great. I passed on the double-baked pork belly last night, but there were plenty of other choices.
Yours truly from the Falkor,
Dana Yoerger
June 25th, 2014
We are underway, headed for the FeMO Deep off the east coast of the Big Island of Hawaii. Thanks to the good work of many, our preparations in port went smoothly. Trucking Sentry across the country and air-freighting it to Hawaii went just as planned (easy for me to say!). Our move onto Falkor was busy, but smooth. We did some practice launches and recoveries at the dock. USBL installation required significantly more work than we anticipated.
Carl Kaiser, Ben Pietro, and Al Duester from the Woods Hole Oceanographic Institution (WHOI) AUV Sentry team stayed on board when we left port. With their help, we did some more launch and recovery tests near the sea buoy. We were in the “real ocean” although conditions were fairly benign. We launched the vehicle without weights and drove it away from the ship. The ship then drove around to practice approaching the vehicle. We made a number of small but important adjustments to our recovery method, changing how we use the air tugger and the knuckle-boom crane. Chris Taylor got some valuable experience driving Sentry, as this is his first time working on this particular vehicle. Mostly, we all got to know each other better, which is of course always critical. We launched and recovered three times and were all very satisfied in the end. On our last recovery, the ship sat “in the trough” intentionally to make things a bit more lively. We also did a CTD cast that included a successful test of the USBL system (a few tweaks were needed)! After a good day of practice, the small boat took Carl, Ben, and Al back to Honolulu. We will start our first CTD cast and USBL calibration tonight and should begin our first Sentry dive early morning on Friday.
Life on Falkor is quite comfortable. We had an awesome cookout on board last night. This included great food, a rainbow, and even some live music courtesy of a newly formed trio from the ship and from science crew.
Yours truly from the Falkor,
Dana Yoerger
