8 June, 1998

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<fontfamily>Times_New_Roman<bigger><bigger>TEA Journal

Day 9

6/8/98

Living in Barrow has certainly taught me to make the most of the beautiful days while they are here because by tomorrow things will probably have changed. This rule of thumb holds true here on the west end of the slope every bit as much as in the central area. The ship is in heavily ridged ice again and has been since shortly after midnight. Progress has slowed to several hundred meters per hour and we are still 45 miles away from the helo launch position. The day is foggy, cold, and windy and as I look out onto the ice I still feel great about the two gorgeous days we just had.

General Quarters sounded again this morning shortly after reveille and once again the beakers made for the hangar. Aaron was in the shower and showed up soaking wet and carrying his shoes and shirt. An amusing sight but added only a moment of brevity to a situation that was very tense with anticipation. The problem turned out to be a burst lubricating oil line to the port side shaft reduction gear which sprayed a lot of oil onto the bulkhead (wall) and into some electrical circuits. The chance of fire was present so setting condition zebra was required. It took about an hour for the immediate danger to pass and most the beakers stretched out on the floor of the hangar and tried to catch a few more winks.

One would think it proper and prudent to pitch in and lend a hand with whatever action the emergency situation required. In fact staying out of the way and not being in the middle of the goings on is by far the better course of action. Damage control on a ship requires a knowledge of the piping systems, wiring systems, ventilation systems and the content and function of each space on the vessel. As new people report aboard they spend the first several months acquainting themselves with all of the above. In order to be qualified to stand a specific watch one must demonstrate that they know the systems associated with that specific space. Hauling hoses and equipment out onto the deck might be appropriate beaker tasks but going below decks or entering smoke filled spaces are activities only for those that have been properly trained.

The ice group went out to collect cores by way of the crane while the ship was stopped. We are not seeing as much dirt on the surface as we have over the last couple of days however the sediment we found within the cores was surprising. The ice is about 170 cm (67 inches) thick and the dirt within the core indicates that possibly one piece had rafted on top of an already existing piece of ice. We punched three cores and then Terry and Aaron went in search of sediment as Bill and I returned to the ship with the cores and got them stored in the cold room.

The ship did not get the shafts turning again until almost 6:00 PM. Crashing and ramming the ice consumes tremendous amounts of energy and as a result takes a steady toll on the engineering plant. The work of the engineers on this vessel is never done and these women and men spend very little of their underway time out of the engine spaces. The Polar Sea is equipped with three shafts that spin at a constant speed, each one turning an adjustable pitch propeller. The pitch adjustment is a hydraulic/pneumatic system and the collar that attaches to the shaft must allow the shaft to spin within it yet be mounted so that the collar itself does not move. Powering the shafts are two systems that can be combined or run in an either/or configuration. One system, called diesel electric has as many as six sixteen cylinder diesel engines turning generators which funnel all the electricity to main control and then down to electric motors which power the shafts. The ship can generate 8,000 horsepower per shaft with this system. The other system involves 3 gas turbines which spin massive reduction gears and which then spin the shafts. The ship is able to generate an amazing total of 72,000 horsepower in this configuration. In the diesel/electric configuration the shaft speed is 130 RPM's and in the turbine mode they spin at 170 RPM's. The shafts are about 1m in diameter and the propellers are about 4m across. Often times when breaking ice the 2 outboard shafts will be powered by diesels and the center line shaft will be powered by a turbine. When all 3 turbines are running the fuel consumption is over 40,000 gallons per day so this system is used only to break through the thickest ice and only for short periods of time.=20

I worked for a while with Bill and Terry in the cold room this evening. It certainly is named appropriately! We sliced today's cores into 10 cm sections and then cut a thin longitudinal section out of each piece. These pieces are then put on a light table that has polarizing filters in place that allow the crystal structure within the thin section to be viewed. One of the things that the CRREL group is looking at is the crystal structure specifically where there is sediment incorporated into the ice crystals. If the crystal structure indicates that the ice is frazzle or jumbled ice such as might form when small chunks of ice come together in cold water then that is expected. However, if the sediment parcticles are incorporated into longer ice crystals called columnar ice, then that is of interest. Ice transport of sediment is being studied not only to determine how much material is being moved from away from beaches and adding to beach erosion but also to determine how parcticulate pollutants might be transported by ice. Neat stuff!

As somebody's shirt here on the ship read, "if we knew all the answers, we wouldn't call it research!" =20

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