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Rothera to Scar Inlet

November 16, 2012
Accumulation pole leaning towards Cape Disappointment.

Accumulation pole leaning towards Cape Disappointment.

Terry writes:

The weather looked very good at both Flask and Rothera this morning, so we took off at 09:35 with my new General field Assistant (called a “GA” in Rothera-speak) Roger Stilwell, Daniel Farinotti’s GA Ash Fusiarski, and pilot Ian Potten. We arrived at Scar AMIGOS2/4 at about 11:05 and did a flyover noting that the slots we saw so clearly nine days ago were not nearly as visible from the air. Also, the accumulation pole was still present, but bent over at a steep angle. Ian decided it looked relatively safe to land near the tower, so after a single touch and go, we landed at 11:15 about 100 meters from the tower.

This greatly simplified our logistics. We roped up without skis, and Roger and Ash hauled the first load of equipment with me walking in the middle. Ash did notice a fairly narrow slot about ten meters from the tower which he probed. He determined its bridge was relatively sound, as were the other slots we found with probing. I started taking photos, while the GAs returned to the plane for more equipment. By 12:04, I was taking the first voltage readings of the 12 volt power supply. The first reading was 0.34 volts with the power cable plugged into the CPU, and unplugged it read 0.44 volts, so clearly the batteries were essentially dead.

Power and solar panel cables leading to battery box encased in ice.

Power and solar panel cables leading to battery box encased in ice.

We uncovered the snow layer covering the battery box. It was encased in a solid ice layer extending to the base of the tower and enclosing the one power cable and the two solar battery cables. I worked on reviving the CPU using the replacement batteries and the new battery box while Roger and Ash attempted to free the solar panel cables from the ice. I quickly realized that the power cable connector on the new battery box had been damaged on the twin otter (since I hadn’t protected it), so there was nothing holding the power cable to the box.

Roger as able to come up with a scheme using a piece of cord that seemed to do the job. When I hooked up AMIGOS-4 to the computer, I could see it booting just fine through the serial port, but I could not get an ethernet connection. I tried three different cables and two different hub ports. Fearing that the hub had died. I decided we needed to swap out AMIGOS-4 for AMIGOS-1. Roger and Ash managed to unbolt the enclosure from the tower and bolt in AMIGOS-1. After reconnecting all the peripherals, I booted up AMIGOS-1. Again the serial port worked fine but I couldn’t get an ethernet connection. Finally I tried re-initializing the laptop’s local area connection, and the ethernet worked fine. I realized then that the AMIGOS-4 ethernet was probably okay, but by now it was 14:30. Roger and Ash realized they weren’t going to be able to free the solar cables from the old battery box, so somehow we were going to have to rewire them. We had two replacement cables, which I thought we could attach to the panels directly, but that would have required working over two meters above the ground, and besides, the cables were too short.

Roger then suggested cutting the cables as close to the old battery box as possible, and then somehow splicing the replacement cable leads to the cut cables. I then remembered that Seth had included some kind of cable splicing arrangement for the cGPS solar panels. So Roger and Ash retrieved the last and heaviest case of UNAVCO parts from the plane and we found the splicing kit.

Meanwhile AMIGOS-1 was cranking out data, including GPS and weather data that looked good. While Roger and Ash worked on the splicing, I attempted three sets of image acquisitions. The camera appeared to work fine, but, just as we had seen in Boulder before leaving, the AMIGOS-1 router was unable to establish an internet connection, and so was incapable of transmitting the images. Once the splicing was done, we tested each panel output and got about 23 volts from each cable. We then sealed the battery box with caulk as well as the power and solar panel connections to the battery box. Ian helped me strap the battery box to the tower. I disconnected the computer from AMIGOS-4 at about 15:55. We then packed up the plane and took off about 16:45. By now it was overcast and we could see a cloud deck covering the top of Cape Disappointment.

New battery box including cord for fixing broken connector and caulking toseal the box from water intrusion.

New battery box including cord for fixing broken connector and caulking to seal the box from water intrusion.

We decided it was still worth a look to see if we could spot the tower and possibly make a landing. We made a couple of passes, couldn’t see the tower, and had poor contrast that precluded a landing. We left Cape Disappointment at 16:56 and headed for cGPS LPRD. Again clouds and poor contrast prevented us both from seeing the LPRD and from landing (I had already seen LPRD nine days earlier, and determined that the bottom of the panels were on the snow surface). We left Leppard at 20:22 and landed at Rothera at 21:29. I’m going to test AMIGOS-4 over the next day or two while also monitoring the ability of AMIGOS-1 to dial-out. If I determine that AMIGOS4 is working better than AMIGOS-1, I’m going to suggest replacing AMIGOS-1 with AMIGOS-4. We think it could be done with about an hour on the ground. To date, AMIGOS-1 Single Burst Data (SBD) messages are working fine, but no dial-outs have succeeded.

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