28 July, 2003
There was a glitch or two, but scientific progress marches on. It didnít seem that way, however, for a few hours this evening.
During a routine cast of the CTD/rosette, an alarm sounded-off alerting us that the CTD was too close to the bottom. Normally thatís a good thing because you donít ever want the rosette to strike the bottom which can damage the CTD. The problem was this: the rosette was 1250 meters above the bottom. Indeed, the CTD warning alarm isnít suppose to activate until itís within 20 meters of the sea-floor. So this was interesting.
Graduate student, Craig Aumack, who was directing the cast, consulted with Scrippsís electronics technician Rob Palomares, and subsequently instructed the winch operator, Danny Plaza, to retrieve the rosette. After a quick inspection by Rob, and electronic technician Brent Evers, marine tech Jenny White, and Dr. Karl Newyear, Craig was given the green light to repeat the cast.
All seemed to be going well until an identical error occurred and the cast had to be aborted again. Now it was puzzling.
Rob, Brent, Jenny, and Karl took an even closer look, and when all seemed fine, a third cast commenced. By this time a new winch operator, Ricky Alvezo, began his shift. And Craig was joined by graduate student Jeremy Mathis and Chief Scientist, Jim Swift in the lab. Everything worked well going down, and three water samples were taken before the rosette completely lost power and failed to transmit data on its return to the surface. It was time to get serious.
Eventually, Rob, Brent, and Gerry Bucher (another electronics technician) determined that there was an electrical short, and possibly a blown fuse, which made it necessary to replace the CTD on the rosette. (The ship carries two spare CTDs.) A couple of new sensor cables were installed too. And for good measure, the last 50 meters of the big cable that attaches the CTD/rosette to the winch was removed by marine technicians Emily Constantine and Jesse Doren (who relieved Jenny and Karl). Over a period of time, the end of the cable gets stressed and becomes work-hardened, making it less flexible, so every so often, it has to be ďre-terminated,Ē or replaced. Finally, the cast was successfully executed.
Plainly put, it was fascinating to observe all the teamwork and trouble-shooting employed by everyone involved. And Iím pleased to report that the CTD has worked just fine ever since.
As I mentioned before, glitch by glitch, science goes on.
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