LIVE FROM...OTHER WORLDS    Antarctica Weekly Report 11-15-93

The week started out with the goal of finishing the survey of the Dayton
transect sites.  Little did we know the kind of problems we would run into
doing this task which we thought was almost complete.  On Monday Nov. 8, we had
all equipment set up and the TROV deployed by 9:00 AM, a record for getting
started and proof that our operation was becoming highly efficient.  However,
after two hours of operation, both horizontal thrusters quit working.  We
recovered and found that the recovery rope was again frayed, even though we had
secured it in such a way that we did not think it could get anywhere near the
thruster propellors.

In the late afternoon, after we had repaired the thrusters, Jim Barry began a
new set of transect surveys using the Sharps navigation system to define the
transect lines.  Transects that we had previously performed were surveyed by
following a fixed line, much as a diver would survey the site.  Now, instead,
we used the Sharps display to determine our position and the length of the
transect survey was determined by the Sharps as well.  The Sharps navigation
system involves deploying a set of acoustic transponders in a grid along with
two transponders mounted on the TROV. An IBM PC receives and processes the data
and produces a graphic display of the data including a track of the vehicle
position over time.  One can drive in a straight line by keeping track of the
past position of the TROV using this track.  We found that, using the Sharps
display to locate the TROV, transects could be performed very quickly.  By
dinner time, Jim was really on a roll and was getting so much!  work done that
we decided not to bring the vehicle back in but to break for dinner and come
back to finish the transects.  We returned to the hut at 7:30 pm and resumed
the survey work.  However, after about an hour, the TROV was in an area where
we could see lines coming up from things Jim said were sediment traps he had
laid out years ago.  I noticed that Jim seemed to have gone by one of these
lines several times.  He noticed it also and, looking backward, could see that
the TROV umbilical had made at least two loops around one of these lines.

The line in question was coming up some 20 feet off the bottom, and had a float
on the top.  Near the top was a large clump of organisms.  Jim retraced his
path to unwind the two loops of the umbilical around the vertical line.  We
thought we were free of it and tried going to the surface.  But, looking down,
we could still see our cable attached to that line.

Jim came back down and drove up to the line, inspecting it carefully.  We tried
pulling in cable and tugging on the line.  We could see that the line was
somehow attatched to our cable, but we could not see how.  There was a big
clump of organisms right where the cable and the line seemed tangled, and we
could not see through it.

Finally, we started using the TROV arm to pull off some of the organism and get
a clearer view.  We tore at the big clump of organisms with the gripper claw of
the arm.  Finally we could see what looked like a knot near the umbilical
attach point.  We tried grabbing the line with the gripper and driving away.
It seemed to us that it was just snagged and we should be able to break free of
the snag with some tension.  However, the snag held on.

At 11:00 pm, after 2 1/2 hours of complex driving, we had not managed to
untangle the line but had made some interesting use of the arm.  However, we
were getting very tired, especially Jim Barry who had been driving continuously
for several hours by that time.  The snagged line was in about 100 feet of
water and we knew a diver could cut the line loose quite easily.  We decided to
break for the night and send a diver down in the morning to cut the TROV loose.
Figuring that we could not recover the TROV with the snagged line, we
reluctantly left it in the water over night.

 The vehicle was snagged about 300 feet from the Hypertat hut, and that was far
too long of a swim for a SCUBA diver.  Instead, we needed a hole drilled as
close to the snag point as possible.  The next morning (Nov. 9), we called to
get a hole drilled in the ice so that a diver could go down it to cut the line.
However, we found that the drill rig was in the shop being repaired.  We were
told it would be ready after lunch.  We spent a nervous morning waiting for the
drill rig repair.  By 3:00 pm, the drill rig was still not ready, and we were
told it would have to wait until the next day.  Our patience was wearing thin.
The previous night, Don had suggested outfitting the gripper with razor blades
and cutting the line loose with the gripper.  However, it was so late at night,
and freeing the TROV by having a diver cut the line seemed so simple, that I
decided against it.  But since the drill rig was broken, it seemed worthwhile
to try it, if we could just get the TROV back into the Hypertat.

Luckily, we had just enough free line to drive all the way back to the dive
hole in the Hypertat. Ordinarily, the umbilical is brought in and coiled up
near the hut until we get to the last 20 feet, where there is a rope attatched
to it which is used to pull the TROV vertically up the ice hole.  The rope is
used to keep strain off the TROV umbilical.  However, since we could not access
that rope without bringing in the snarled umbilical, now we had to get a
grappling hook down the hole and grab the TROV by the crash frame to pull it up
the hole.  The machine shop in McMurdo quickly rigged us a 10 foot long
grappling hook to lower down the hole, and we snagged the TROV crash frame
without any problem.  Soon the TROV was back in the Hypertat.

Don quickly installed razor blades from a utility knife in the TROV gripper.
We tested the functionality of this cutter by chopping several pieces of rope
with the gripper in the hut.  The gripper looked a bit like Edward Scissorhands
and we knew we had a killer TROV as we lowered it back down the hole.

Once in the water, we quickly followed the tether back to the line we were
tangled on.  We grabbed the line several feet below the tangle spot with the
gripper.  By moving the arm up and down and twisting the wrist back and forth
we began to saw through the line.  After about 5 minutes we could see the line
starting to fray and in 5 more minutes we were free, with much cheering and
jubilation, I might add.

We brought the TROV back to the dive hole and started pulling in line until we
came to the monster that had trapped us..  Wrapped twice around the umbilical
was a 3/4" nylon line tied to a float and, just below, a large clump of plastic
dish cleaners hooked together with a wire.  The dish cleaners were settlement
surfaces for organisms to grow on, and lots of things were growing there in a
mass 18" in diameter.  This trophy was taken to the McMurdo Aquarium. Edward
Scissorhands had triumphed.

One of our motivations for attempting to self rescue the TROV was that we had a
planned remote operation at Ames the next day in which students were being
brought in to operate the TROV. However, when we awoke in the morning (Nov.
10), we found that the STARS system (the communication satellite system) was
down for repairs and we had no communication with the states, not even by
telephone.  Our remote operation was scheduled to begin at 10:30 so we went to
the Hypertat to be ready if STARS came back on line.  At 10:00 AM the problem
had been fixed and we began remote operation from Ames. At 10:30, Geoff
Haine-Stiles arrived at Ames with a group of Junior High School students.  Some
of these students were allowed to operate the TROV without any prior training.
While they were driving around, Dale Andersen fielded questions from the
students about what they were looking at in Antarctica.

The remote test ended at noon.  After lunch we resumed science transects, again
using the Sharps Navigation system to get directional information.  Jim Barry
drove local transects until he finished surveying the area.  Next, Mike Sims
and Butler Hine each took a turn at driving transects by remote control from
Ames with Jim giving them instructions and pointers over the telephone.  This
day was remarkably productive, and at the end of it we were ready to move to
the next dive site in deeper water.

The next day (Nov. 11) we planned to move to a new site.  The move was
scheduled for afternoon, so we went to the Hypertat in the morning to pack up
for the move.  By this time it had been snowing almost continuously for over a
week.  By mid-morning the wind had picked up and was blowing the accumulated
snow so that the visibility out on the sea ice was less than 50 feet.  We were
finally experiencing Condition 1 weather, and not just experiencing it but
working in it as well.  Fortunately, by now the weather has warmed enough that
we could work outside in the high winds without too much danger of frostbite.
But everything took much longer because of the deep snow and low visibility.
We barely got moved to the new location by the end of the day.

The bad weather continued for the next two days, and we decided to spend them
performing some needed maintainance.

On Sunday, Nov. 14, we got the incredible good fortune to see a partial solar
eclipse in Antarctica. McMurdo was not in the totality path, but the sun was
97% eclipsed at the maximum point.

In the morning, we got together with our friend Eugene Miya from Ames. Eugene
is working with a team that is going out to Icestream Bravo, a rapidly moving
glacial ice stream.  Several members of the Bravo team joined us and we took a
Sprite ride out to a good place to watch the eclipse.  The eclipse was at
maximum at 10:30 AM and we thought, given the sun position at that time of day,
an ideal place to watch it would be out on the sea ice South of McMurdo. In
this direction about 5 miles out there is an interesting terrain feature in the
form of an iceberg that drifted into McMurdo sound last summer after the sea
ice had broken out.  It eventually ran into the permanent ice to the South of
McMurdo and there became grounded.  The iceberg is roughly 100 feet high and
1000 feet in diameter.  It formed the perfect backdrop for watching the
Eclipse.

Since the eclipse was not total, we could not look at it with our naked eyes.
We brought along some glass plates from a welding mask through which we could
view the sun.  Various attempts were made to photograph it, and by covering the
lense of a video camera with the glass, we were able to get video of the
eclipse.

Fortunately, the stormy conditions of the previous week and passed and we had
glorious weather for the eclipse.  In fact, the weather has become downright
hot.

After the Eclipse, Eugene and I, who had brought skis, sent the rest of the
crew back in the Sprite and stayed at the iceberg.  We skied cross country from
there up to Castle Rock.

Castle Rock is a volcanic cinder cone from Mount Erebus. It is a dark red
angular precipice of rock jutting several hundred feet in the air on the ridge
above McMurdo. The rocky soil around Castle Rock is comprised of Palagonite, a
weathering product of basalt which forms in cold arid regions and is an exact
spectral match to the soils on Mars. The terrain around Castle Rock is some of
the most Mars-like terrain on Earth. Castle Rock is the favorite hiking spot
from McMurdo. In fact, it is the only legal hiking spot.  It is an easy rock
scramble to the top of the rock and well worth the trouble to climb it since
the climber is treated to spectacular views of Erebus and the whole of Ross
Island. I felt blessed to be able to experience the beautiful view, the
wonderful weather, and the solar eclipse all in one splendid day on THE ICE.
---
  Via FTL BBS (404-292-8761) and NASA Spacelink (205-895-0028)
