WEDNESDAY, 02.11.09

0414: Shakedowns Complete
We got off the dock yesterday morning at the prescribed time, ran out about 20 kilometers and started our testing. The bathymetry run using the ship’s fathometer showed us that we picked an area with a lot more vertical activity than the charts indicated (this is becoming a somewhat annoying constant, the inaccuracy of charts. If only someone out there would provide the world with some more accurate bottom data … oh yeah, never mind).

We met, discussed it and decided we were going to need to face this challenge some day, might as well be now before we get to our grounds. We know there are seamounts out there, and we also have some potential search areas near the islands where the bottom is ugly. We gotta do it sometime, let’s do it now: time to put the pencil beams to the test. Also, we wanted to give this new software a chance to see how it handled some of the bugs - false detects in the pencil beams (collision avoidance), sonar resets due to file writing cessations we saw on a couple missions during trials and some general tweaks to the system.

Tangible Search Grid

The team refines plans for the survey missions

So we proceeded with our plan. The CTD (Connectivity, Temperature and Depth sensors) cast to test the releases on our four primary Deep Ocean Transponders (DOTs) went off well, all released with no indications of any problems. We then lined out to test our trawl net. This turned into a snarl, literally. The deck team did not make sure they had sufficient weight on the cable leading from the upper deck winch that tows that system and the cable back-spooled on the drum. That test was canceled while they sorted the resultant bird’s nest of wire. We have a period during the transit when the ship will have to slow for a couple hours for routine maintenance. We’ll do a tow then.

That left us the remaining task of getting the girls wet. We set two DOTs and surveyed them in. Mary Ann went in first yesterday at 1756 and ran her mission until 2130 when she aborted due to a timeout. When we looked at her data and telemetry we determined that everything was doing what it should. She was detecting rises and falls in the terrain in front of her and this prevented her from completing one of her lines in the time allotted, which set off her safety features and she aborted. When we looked at the data we could see that she would rise up into the water column in front of a wall and sometimes be taken off her path by current. When the path cleared in front of her, she would drive back over to the line and proceed. One of the times this happened, it simply took her too long to finish the line and she aborted. This is pretty much what she’s supposed to do. We put Ginger in at 2230 and had her run a little bit higher off the bottom. I think they lengthened the timeout interval as well. She just came back out today at 0225, mission completed.

Both vehicles performed well within their specification and provided us with a lot of good data to learn from, to maximize our potential when this happens in the future. I think the new software is performing well, which basically means that the vehicles are running better than before.

I just gave the go ahead to retrieve the DOTs and informed the captain we were done with shakedowns. We’re on our way to our grounds as soon as we get the DOTs aboard and the gear stowed. Time to get to work on the reason we came out here. The first DOT is already aboard. I expect we’ll be underway by 4:30 a.m. Trials ran approximately 19 hours, so we are perhaps a day behind schedule. We should be on station and working in four days maximum, according to the plot at 10 knots. We’ll shave that down, I’m sure.

That’s it from radio Dessner. I am going to bed!

RVSJ BEGINS TRANSIT TO HOWLAND ISLAND

0430: We’re On The Way

1201: To Ted Waitt, Schedules
We are scheduled to arrive Sunday (02/15/09) morning at 6 a.m. We are currently running at 10.5 knots. The ship’s crew is working on a four-hour on, eight-hour off schedule beginning at 8 a.m., three shifts, twice a day. The ops team works 12-hour shifts from noon to midnight.

Ship meals are at:
Breakfast 0630-0730
Lunch 1130-1230
Supper 1730-1830

We are going to keep the Samoan clock which has us three hours behind San Diego time. Once the vehicles start rolling, there’s not much predicting when they will go in and come back past an 18-hour bottom time. We roll them back in the water as fast as we possibly can; it gets kind of tough to call once one aborts for whatever reason.

1347: From Ted Waitt Re: Schedules
Do you do a daily briefing?

1359: To Ted Waitt, Re: Schedules
Right now we are not and the ones we did during sea trials were pretty much ad hoc. There has been some resistance to my suggestions on this, although I think we will still meet on the bridge at noon each day once we commence operations. It’s been tough for me to get something a bit more formal going. My suggestion would be at noon, all department heads from both shifts and the captain.

1555: To Ted Waitt, Re: Schedules
One option for us would be to hold it in the ops lab, probably best actually. That way we could go over targets on the system.