Monday, June 6, 2011

A Brief Visit From the J-Box

Sunday morning before my 0400 Jason watch, I took my hot cocoa up to the bridge to see the stars.  Up there, I’d heard, you sit above the reach of the bright deck lights so nothing gets between you and the stars. It was true. Between the twinkling and many up there, you could even see a faint smudge of the Milky Way.  In addition to the light from the stars came fleeting but thick strokes of lighting. A squall dead ahead was shouting grey and electric warnings. Luckily, we were static on station so though headed straight for it, we got no closer.   Even 100 km away, you could see a faint orange glow off the starboard bow on the horizon originating from Oahu.

At 0400, I arrived in the van and was greeted for a second time by an unexpected display of water column. For a second time, while I was sleeping, Jason had been recovered and redeployed.  This time it was to prepare Medea with the bridle to bring the J-box back to the surface. Overnight, Jason’s fiber optic bellybutton had been plugged into the cable termination to test the signal. The results from that test were somewhat encouraging – Makaha received a signal back but at a lower intensity than desired. With the time remaining on the cruise, the plan was to recover the J-box and reconfigure it one last time, changing the attenuation as well to decrease the signal loss.

This dive was slightly more challenging than others for the Jason pilots, engineers and navigators because Medea’s compass was misbehaving. This meant that Medea, who usually can be put on autopilot, must be watched and tended to constantly. The only way to determine bearing on Medea was to align itself with Jason’s heading from the cameras. The Jason team completed the task without hitch and the J-box was back up after lunch.

The J-box was put through the same spa treatment as a few nights before, except this time with more rapidity. Rinsed and toweled down, the titanium casing in which the fiber optic system resides was opened and its innards exposed. Cables and attenuators were examined through microscopes and gadgets measuring loss in dB.  Inspector Gadget made an entrance wearing a newer and dorkier form of investigation – a headband with high magnification glasses that fold down. Once the right set of attenuators was selected and the correct pin reconfiguration was triple checked it was time to prepare the o-rings to seal the casing back up. As with other instruments of Jefrey’s, he took great care in wiping down the o-ring seats and the o-rings themselves with Kimwipes, then a little grease. As there is really only room for one head to be hunched over the open casing, we all stood around Jefrey as he meticulously inspected for hairs and dust – surely making his job easier. With happy o-rings, they closed the casing up and retrieved the vacuum pump. In order to make sure that all the humid air is evacuated from around the sensitive equipment, they suck out all the air and refill the chamber with helium, an inert gas, three times.

After dinner, the J-box was anxious to jump back in. We all said our last goodbyes and took our last pictures. True to our deployment style, the sun set in the background and the quarter moon had risen above the A-frame making for great documentation. With a little more than a day left, this would likely be the last dive of the cruise and hopefully the one in which the puzzle pieces lay flat to see the whole picture.

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