MONDAY, 04.27.09

1212: Day 21 Update
It has been roughly four days since you last heard from me. My apologies, but it really has been pretty much the same old, same old. That is one of the things about being at sea that is fairly distinctive, the tendency for things to kind of blur together. I guess that would actually argue for keeping pretty good logs and journals, but for the purposes of this continuing entry, I really do not see the value of just stating the launch and recovery times of the vehicles since those are covered in two other logs we keep. It does help the time pass a bit for me personally; I think of it as akin to looking at your watch every five minutes, time seems to slow down. These last few weeks have been going by fairly quickly, and the vehicles have been presenting few issues. The days tend to melt together –  you never really know what day it is until you get to a calendar and look. The main delineations are your meals, Saturday is ‘Steak Night’ and you just look forward to the next one. They seem to come with increasing frequency as long as you are not checking off the boxes in your calendar.

People’s tempers have become just the slightest bit shorter lately. It’s not so much that morale is down; people are not dejected, nor are they showing signs of doing a poor job. It’s just that folks have a tendency to disagree a little quicker, to argue over little things and then silently bear each other’s company afterward. I think the same thing happened on the last trip. After about 30 days, you live in your own little world and any interactions are more likely to interfere with your personal gravimetric field. Like astronomical bodies, it’s okay to pass by closely, but you don’t want to slam into each other. As long as everyone gives everyone else the room they need, we keep spinning along nicely.

Since my last report on April 23, we’ve had six additional missions. With one exception, all went off with no issues. That exception was because of our first serious operator error on this Leg. During the launch of the vehicle, the system sonar was not properly checked to ensure it was recording sonar data on the surface. When it came back up 20 hours later, there was no data in the record at all. This was doubly unfortunate because we were right on the edge of finishing the E/F boxes. Last week we had an issue with one of our Deep Ocean Transponders (DOTs), so we skipped the problem area and went south to work our way back north, leaving an ever-decreasing space between finished areas. We needed to finish some work in the south so we could obtain a DOT with the proper channel to replace the problematic one. The E/F boxes require more DOTS for the vehicles to get their fixes.

Essentially, the A/B rows are rectangles on a long axis, each set of boxes only requiring a DOT at the upper and lower intersection. The E/F rows are squarer, requiring DOTs on the upper and lower intersections, and one in the middle. This may seem a less efficient use of DOTS (more farming and planting of DOTs), but it suited our coverage purposes. We’ll have the same issue with the C boxes since the vehicles will not be working in two boxes that are alongside each other, but in two parallel boxes. It uses a bit more fuel for farming, and we have to take extra care to make sure we keep the proper sequence of DOTs, but it suits our coverage needs.

When one mission came up without data, we suffered a fairly serious 18-hour loss in productivity. We planned to put both vehicles in the water to finish up the last box, but that wasn’t possible due to a crack in one vehicle’s altimeter cable. That took six hours to repair, and then we had to make the call whether to put both vehicles in the water or go back down to the south and clean up the three DOTs remaining there. If we put both vehicles in after one suffered a six-hour delay, the only benefit would be the time when both were working. The first vehicle had the entire box programmed into it (to cover the eventuality that we did not get another vehicle in), so when they closed on each other, one working north to south and the other working south to north, we would eventually have to abort one. The DOT farming would take roughly four hours; the delay in the launching of the second vehicle meant we would not have a four-hour window to safely send an abort command. Therefore, I made the decision to leave the job to one vehicle and go farm the DOTs. When the vehicle in the E/F boxes came up, she had all her data.

Of the vehicle launches in the last few days without issues, turnarounds averaged three and a half hours. Not great, but given everything that was going on, not too shabby. At this time we’ve finished all A, B, E, and F boxes. We’re now picking up all our toys and heading over to C with two fully functional vehicles and all our DOTs. At this minute, we’re steaming to the northern end of the C boxes, where we will lay down five DOTs and survey in three, launch the ladies, survey the remaining two DOTs, lay in three more and then start turning gear.

Productivity on this Leg remains head and shoulders above what we saw on the first Leg. Once our transducer issues ceased cropping up every other day, things smoothed out to what we hoped we could accomplish with the system. I have included a mosaic of the first Leg, plus a map showing the area we’ve covered to date. In the map, the shaded area represents 1,664 square miles of mapped bottom. It’s truly impressive. We’ve had 100 evolutions of the equipment, and each lady has over 50 missions. When we finish this job, we should have roughly four times the coverage of the 2006 survey in about twice the time. This system is truly revolutionary, a quantum jump from previous capabilities in deep survey.