Cape petrels drifting on the side of the Polarstern (picture by Marie).
29.01.2013 (Tuesday). I wake up late
as I thought that I would have little to do today. A supposition, which will
turn out to be definitely wrong. Outside,
in the morning it is quite foggy and the ice coverage of the sea is weak at
that time. I look at one of the wall screens displaying the time schedule of
the day. I see that we will have to test our acoustic larger today at 12:30. It
is important to test if it works properly before fixing it to the lander.
Indeed, it is a very expensive gear and we should take as little risk as
possible to loose it. I have a bit of apprehension because I have little
experience with it (six years ago it was my colleague and friend Henri Robert,
who operated the system). However, everything works properly. We fix the hydrophone
to the telecommand. We put it on. We send the command of opening the hook of
the larger. It opens properly. We close it on a metal ring, which is supposed
to be released during the test. Then the larger is attached to a cable. The
large and heavy (30 kg) cylinder of the larger dives to 200 m depth. The hydrophone (attached to a 10 m cable and
connected to the telecommand) is put in the sea. We put on the telecommand. We
successfully send (1) the message of loading and (2) the message of releasing.
Two very long seconds and the telecommand makes a bip, which indicates that the
larger has received its message. The
larger is lifted up. the hook is open and the ring has been released to
sink forever into the abysses. So, so far, so good. But...
Testing the larger (picture by Marie).
Now that we know that the acoustic
larger works, we decide to fix it on the
lander (the cubic cage, where the baited traps will be fixed). We soon have a
confirmation of a problem, which I was fearing. When trying to insert the heavy
larger between two bars of the lander, it does not enter. The lander has been
constructed very carefully by Luc Trevels in Belgium and everything was
calculated to the millimeter. When it was sawed and resoldered, the lander
became a few millimeters too short, hence the larger can no longer be inserted
at the right place. With the help of the crew, we try to increase the space of
insertion. First with a huge hammer: it does not work at all. Obviously, an
even more drastic method is required... The bottom of lander is firmly fixed to
the deck with rope and the top is pulled upwards with a crane! By this process
the top of the lander is slightly twisted upwards and now it should become
possible to insert the larger. Yes the lander now enters but another problem
arises. Due to the recent harsh treatments it has recently endured, the lander
is now slightly distorted. There are holes (for bolts) on the larger and on the
lander which are supposed to be in a straight line (4 upper ones and 4 lower
ones). This, I can only be checked in laying on my back in the cage, just under
the larger. In this position I fix a first bolt. Then I see that the other
holes are no longer in a straight line. I remain on my back under the cage to
control the situation, with a bolt in my hand. With the help of the crew, we
twist the lander once again (now the inner bars) to rectify the position of the
holes. As soon as a hole of the larger is in the straight line of the
corresponding hole of the lander, I insert a bolt and start to screw it. I put
the This proves to be very difficult for all of us. With great difficulties we
managed to fix the four lower bolts. We have even more difficulties to fix the
last upper bolts, and we only manage to fix three on four of them (but this
should be enough). The larger is now almost ready for use. There is just to fix
one more buoy, the flag, the radio beacon and the flash, but that should be
easy operations and we have time. We will not use the larger before several
days but the most difficult task is now behind us.
Stretching the lander with a crane...
Cédric entering in the cage.
Cédric in the cage.
Cédric trying to insert a bolt inside the cage, with the help of two memebers of the crew.
Larger seen from inside the cage.
Bottom of the larger with one (of four) bolt fixed: that is what you see when you are on your back in the cage.
Once insereted, the bolts still have to be screwed.
During all these painstaking
operations, we are enjoying an extraordinary scenery. We are again deep into
the ice, but whilst so far the sea was calm, now there are low waves. So the
iceflows slowly go up and down as if they were colossal white scales covering
the back of some mythological reptilian sea monster. This is a sight I will
never forget.
Ice dolmen
At the daily general meeting at 19:30, we are informed that we
will get rough weather tomorrow. maybe winds of 9 Beaufort. So during the
evening we attach all our stuffs properly. Or at least we hope we have attached
them properly enough (we are scientists not sailors...).
At 22:45, I look by the window of my
cabin. We are completely stuck into the ice.
(Cédric)
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