TARGET 4: BARREL

SUNDAY, 5.03.09

0958: Days 25 - 27 (May 1 - 3)
Well, we haven’t had the best couple days, and just now, this has been capped off by a somewhat hairy recovery. As you know, the vehicle is recovered by fairly ingenious pieces of equipment working in tandem. The nose of the vehicle has a detachable segment that acts as a float. When this is remotely released, we give the vehicle a command to back itself down in the water, which opens up space between the vehicle and the float so that a line can be attached between the two. We then fire an air-powered cannon that throws a grappling hook (attached to another line) over the line between the vehicle and the float. We use the grappling line to bring the float to the ship, remove the float from the line attached to the vehicle, attach the line from the LARS to the now bitter end of the float line, move the ship forward slowly while maintaining pressure on what is now the recovery line, slowly pay it back behind the ship until it is taut, and then use the winch on the LARS to haul the vehicle back towards the stern of the ship and into the LARS.

It is a fairly complex dance of personnel and equipment, usually taking place with four to five people back and forward along the starboard rail, stumbling across cleats and bollards, various equipment and lines, hydraulic hoses and sometimes squeezing between the ship’s A-frame and the rail towards the stern. There are a few ways this can go wrong. The first way, as well as the most common, is for the solenoid that releases the float to fail (others include gun failure, failure to properly tend lines, failure of the ship to make an approach that lends itself to all the motions of the dance and the ultimate, actually running over the vehicle with the ship).

We have developed various plans for a float release failure. The immediate action is to sidle the ship next to the vehicle so we can rap on the float with long poles. We do this amidships (see the ultimate failure mentioned as a potential result of doing this towards the stern). Another option is for us to put a swimmer in the water and we’ve done this four times, but the option is limited to the sea state and time of day (we will not put a swimmer in at night). The last, which to date we have not done due to its impact time and infrastructure, is to launch a small boat.

Very early this morning when Mary Ann came to the surface, we suffered a float-release malfunction that turned out to be a rotated pin in the solenoid assembly. The crew fixed the problem by sidling the ship up next to the vehicle and giving it multiple raps with a pole, while others held it away from the ship. The fear was that the vehicle could slip under the ship and get damaged. This particular evolution, the ship still had some forward sway and we ended up working down the side of the ship toward the stern, which severely limits our options — we do not want to engage the screws and have a repeat of the previous damage situation — so we just kept pushing, prodding and letting the situation unfold as it would. The vehicle did slip under the stern, but popped out in a few seconds, none the worse for wear. When we had 10 meters separation, we engaged the screws and came around for another try. We brought her alongside amidships again, got a hook in the cage around the upper transducer to help hold it off and tried multiple times to pry the float free. We finally deployed a Jacobs Ladder (rope and wood ladder) and sent a man down to pry it loose with a screwdriver. That worked. We grabbed the line and allowed the ship’s motion to walk the vehicle down the starboard rail. When she was astern, we engaged the screws, trailed her and ran her up into the LARS. The whole episode took about 45 minutes and was pretty hectic with some fairly high drama.

This little gem topped off a couple of fairly messed up days. As you may remember, a few launches ago we had another issue with Ginger’s sonar not communicating with the vehicle (This problem is definitely going to be something we address before we go to sea again.) When we finally got her back down, the problem evinced again at depth. When Greg Packard tried to abort her, he accidentally aborted the wrong vehicle. The user interfaces for the vehicles are identical when two are below, so it’s as simple as not switching a tab on the toolbar. I would have fizzed hard had it been anyone other than Greg, but as it was I had to cheer him up — he was much harder on himself than I ever would have been.

It should also be pointed out that Greg is easily working the longest hours and is the most important guy to this effort. He knows the girls inside and out, has been through some tough times out here — including difficulties back home — and still chose to come back out for the second leg. He has become a friend and an asset that I can barely imagine doing without when it comes to keeping the girls tuned and running.

Anyway, just because things come in threes, when Ginger came up from her next mission, it looked like we finally suffered the failure of the last of the 75/410 transducers in service. That meant we had a mission with only one channel of data. Instead of troubleshooting a system we know is failing, we went ahead and put in the 120/410 transducers and got Ginger back to work. None of the original transducers is now in service.

So we took a couple hits — Ginger down six hours the other day, an accidental abort and a lost mission to a bad transducer. As Ted Waitt very accurately observed, people are getting tired and the routines have turned to rote. It’s tough to find ways to mix it up. I don’t want to break up teams who have been working together for a month; they’ve sorted out their responsibilities nicely, and I fear a change at this point would bring more upset to morale than improvement to productivity. However, I am trying to keep a closer eye on things and I keep second-guessing people. I don’t mind too much if the crew is merely irritated with me, as opposed to each other. It’s really all I can do, I think, to just keep everyone mindful and attentive.

We did make one re-imaging run on a target that turned out to be a 55-gallon metal drum. I have included Andy Sherrell’s original report to Ted and his subsequent follow-up on this entry. We have roughly a baker’s dozen of non-surveyed boxes on our current agenda and 10 days to do it; it’s possible and I hope for it. The analysts are going through the data again and again to make sure we haven’t missed anything. The re-image of the barrel did nothing to dent our confidence in target assays to date.

Mary Ann’s data from this morning’s recovery looks good, and she should get wet again in an hour or so. A breakdown on the times is as follows:

April 30:
0233 Launched Ginger to survey 3/5C
0508 Conducted two-hour trawl to 1,500 meters
1320 Transited to DOT
1320 Released DOT
1617 Recovered DOT
1852 Recovered Mary Ann
2337 Launched Mary Ann into 2/4C

May 1:
0039 Recovered Ginger
0254 Launched Ginger
0307 Ginger loses sonar, recovered into LARS
0404 Re-launch Ginger
0420 Ginger faults at 900 meters, re-sets, aborts
0433 Mary Ann accidentally aborted instead of Ginger
0512 Recovered Ginger
0613 Recovered Mary Ann
0806 Launched Mary Ann to survey 4/6C
1429 Recovered DOT/troubleshot Ginger
1701 Launched Ginger to survey 5/7C
1730 Transited to deploy DOTs
1926 2013, 2047 Deployed DOTs
2055 Began DOT survey

May 2:
0125 Completed survey
0346 Recovered Mary Ann
0419 Conducted plankton net tow
0648 Launched Mary Ann to survey 6/8C
1112-1340 Conducted net trawl
1459 Recovered Ginger, switched transducers
2016 Launched Ginger to resurvey box 5/7C

May 3:
0415 Recovered Mary Ann