It is 7:30 p.m. local time, and the pilots
are finishing repairs on ROV
Tiburon's manipulator arm in preparation for another dive. It
has been a day of mechanical challenges with the manipulator. Two dives
were already attempted today but had to be aborted when the arm wasn't
working properly. The pilots worked all afternoon and through dinner to
fix it. Tiburon has just been dunked in the moonpool as part of the
checkout before the dive. If it passes these tests, the dive will begin.
The dive will be short: an hour descent to the seafloor, an hour of
measurements with the laser Raman
spectrometer (LRS), and an hour to return.
Sheri White and Bill Kirkwood (at left with Peter Brewer) reconfigured the LRS system for today. Yesterday the sampling lens, or optic, in the system was an immersion probe, a metal tube with a lens behind a sapphire window that penetrated through the pressure housing. Today's configuration uses a non-contact optic that sits behind a dome window and can be focused on the sample. The LRS has been put into a stand that was attached to the "front porch" area in front of Tiburon's cameras (see below). Once at the gas vent, the stand will be placed on the seafloor. Tiburon will dig out pieces of the solid hydrate that form in the sediment. The funnel will hold the hydrate sample in place beneath the probe head, and the spectra will be measured.
The LRS system and stand attached
Unfortunately, the manipulator arm failed the in-water tests this evening. The pilots have determined that it can't be fixed for this leg and have decided to install an older, different arm. They have a long evening ahead of them to get everything working by tomorrow.