UPDATE 27 november 2020:
Here are some underwater images of the large ring made with robot submarine 'Victor' from the french research vessel 'Pourquoi pas ?'. The vertical mooring lines have unfolded beautifully according to plan. The whole deployment has thus been successful. The stuck brake parachute was cut loose and salvaged.
Day 12: On a perfect day with very little wind and waves, the towing service arrived just a little later than planned. The big ring takeover of the tug to the Pelagia went smoothly. Two lines were disconnected from dinghies and taken over by the tugboat, after which the Pelagia maneuvered closer and took over the two inner tow lines from the two dinghies. Then the entire ring was checked.
On the outside, straps of acoustic releases were removed and some repair work was done on the ropes. In the ring, the locking pins of all 45 buoys were removed. On the spot it flowed about 1 knot. After the Pelagia parachute was lowered and attached to the large ring, all 36 lower valves of the steel tubes were opened.
Opening the top taps made the ring sink seemingly flawlessly, albeit almost two times faster than expected. The braking parachute was already working before the ring was completely submerged. The triangulation of the 6 acoustic releases at the bottom of the 6 drag parachute lines shows that the ring has in principle landed round. All 6 releases then disconnected normally.
After re-calling, it turned out that the drag parachute did not come up, because 2 of the 6 lines somehow got caught on one side of the ring. Dredgen now makes no sense and may destroy more than it does well. Video recordings with an underwater submarine (ROV) will have to provide a definite answer about the cause of the jam and about any damage to the ring of the less than optimal landing on the seabed. It is still unclear whether the ROV will be able to cut the drag parachute. As far as we can see now, a maximum of 5 of the 45 vertical lines are hindered by the drag parachute. All in all, not a bad result, for now.
Position were the construction has been lowered, at the foot of the southern French continental slope of the Mediterranean.
Day 11: We are on our way!
Day 10: Quarantine
Day 9: The last 4 packages were assembled within 2 hours today. The phase-out phase takes more effort than expected. Especially connecting the synchronization wires is difficult, we have only done 2 of the 6 groups. For the rest, we need at least another day. The entry of the Pelagia made up for a lot. Unfortunately, we had to stop earlier for the PCR test.
Day 8: 41 packages mounted, 4 more to go. Nice weather, but unfortunately also windier than the previous two days. The assembly raft continues to prove its worth, but the two 2 hp whisper engines now have to be helped with pulling ropes from the quay. From tomorrow we will be in the completion phase: tightening a lot of cables. And of course PCR testing.
Day 7: We mounted as many packages in the water today as in the previous two days; two-thirds are now ready. It's a lot of work, but the weather helps us. All around us it seems worse.
Day 6: One third of the packages with temperature sensors etcetera are now connected in the steel cable network in the water. That took more effort than expected and it turned out to be a very long day, in good weather, though. Except for a downpour yesterday, we are lucky with the weather so far.
Day 5: The first 5.5 packages with temperature, 125m of cable anf top-buoy are mounted in the cable network; until a huge downpour with some lightning made further work impossible for today.
Day 4: Because today is Thursday two photos. Another long day, in which we managed to establish the main points with the necessary effort. With the telehandler we pulled the entire network into the ring via a pulley across the quai, in several stages. Securing transverse lines was done via the zodiac, of which the outboard motor has now been well tested.
Day 3: Days 3 and 4 are on our schedule for the assembly of the steel cable network. The entire network has been laid out on the quay today and the assembly raft is under construction. In between the activities we receive regular visits, today among others from the head of the 'capitainerie'. And that while we work on a quay in a corner of the harbor, shielded by a security post.
Day 2: Today was a long working day, but we managed to get the entire large ring in the water. Quite a hassle to lift it out of the water every time to tighten the bottom bolts. Without the cables in it, the ring flexes properly, even in light wind. A beautiful sight.
Day 1: First day here in La Seyne-sur-mer (Toulon, F) went very well, despite a fresh Mistral wind. The NIOZ camp has already been fully set up and all 18 pipes are linked in pairs on the quay. The trucks were unloaded before 10 am. Tomorrow, little wind is forecast and the tubes will go into the water of the port.