we continue to test the ship's equipment. the bow thruster has gone out and it is a challenge for the bridge crew to maintain precise
locations for our coring operation. we hope that the part that is broken is not one that is not on the ship...
also, we are coring again in relatively deep water (5,800m), so the winch has been failing. basically, it goes into free fall mode. and
then the winch operator needs to put on the brake. the piston core we are using now is very sensitive to vertical motions up-and-down,
so we need to be careful not to abruptly change its velocity or it will 'pre-trip' during the breaking and re-descent operations. if it
pre-trips, we loose the ability to do a piston core (where the piston sucks the sediment up into the core) and our device is simply a
gravity core. so, we would probably just bring the corer back up on deck and reset it for a second deployment. doing this operation on
the aftdeck (becaseu the equipment is broken to do it otherwise) is the most dangerous coring operation that the coring chief has done
in his 30 yrs of experience. i have videos...
a second problem with pre-tripping is that the core usually drops with sufficient force that the cable snaps and our $50,000 equipment
gets delivered to davey jones. fortunately, we believe the shock absorber i designed (with the assitance of an engineer to make sure we
were orders of magnitude on the right track) saved us from losing the coring equipment during a pretrip we have already experienced.
glad i spent all that time working on that (about a month). more planning to do...
safety first! jay
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