Dave Ward, Louis Florit and Mike Jankulak worked at the SRVI1 CREWS station from Wednesday, June 29th through Friday, July 1st, 2005. This is a brief breakdown of the work that was done:
June 29th, AM: Dave Ward lowers the station and installs the ladder. We attempt to measure voltage leaks to the ocean but the tests are inconclusive. High voltages are measured even when all instruments are disconnected from the datalogger. At this point, the old camera/transmitter connections to the datalogger are severed and never reconnected. Conditions are extremely choppy with some rain.
June 29th, PM: Rain delays further work. After consulting with Mike Shoemaker by phone, we try to measure voltages to the ocean in a different way, and this time NO leaks are measured, even with most instruments reconnected to the datalogger.
June 30th, AM: The Surface BIC (light sensor) is evaluated by switching to a different cable and light sensor. We find that the old cable appears to work but the old instrument is broken and completely unresponsive. We mount the replacement instrument and connect it using the old cable. With the Underwater BIC, we find that the old instrument AND cable are both broken. We connect the new instrument with the new cable that will simply run up the outside of the station. The new cable is wired into the datalogger box. The Underwater BIC's mount is damaged in removing the instrument so the spare BIC mount that we brought with us is used to deploy the replacement instrument. We also find that the RS-232 connector on the old Surface-BIC cable is broken so we wire it to a new connector. Conditions are still very choppy but skies are clearer.
June 30th, PM: We find over lunchtime that the Surface BIC is not working. We decide to replace the Surface BIC cable as well as the SIO4 that connects to both BICs, the CT and the CTD. We also connect the CT to confirm that it is still working. Unfortunately, when this work is complete, the CTD is no longer communicating with the datalogger. Several different tests are attempted but in the end, the only thing that works is to switch back to the original SIO4 unit. Either the new SIO4's "port 4" is broken or there is something wrong with its programming.
July 1st, AM: We raise the station platform, disconnect the CT, and tie up all loose instrument cables. We also do two sets of (light) profiler casts.
Conclusions: The Surface BIC and Underwater BIC have been successfully repaired. Examinations of data since March/2005 suggest that the malfunctioning windbird may have corrected itself. In any case, no work was done on the windbirds. Also, the data shows that the CTD's pressure sensor has been broken for several months now, and we must either replace the pressure sensor's tube or the entire CTD. Dave Ward should be able to accomplish this if we ship him the necessary parts and give him detailed instructions.
Note that only the CT and CTD are still connected to the original underwater cables. We would not be surprised if either or both of these instruments eventually fail, and there is still the risk of these cables causing systemic problems to the station's power supply and other instruments. Our best guess right now is that the Underwater BIC's cable failed, drained power from the station and perhaps caused the two BICs to malfunction. The windbird issues and CTD pressure sensor failure appear to be unrelated.
-- Mike J+