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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