Wednesday 13 August 2014

Storm anchoring.


When we where anchored at a nice Northerly bay of Tinos, we were facing 7 Beaufort, but the rocks around the village shielded us so we mostly felt just 5 Beaufort. We arrived in the Bay just after dark, and Elizabeth used the radar to drop anchor in the center of the bay. As we where anchored in 12 meters of water, we decided to drop 55 meters of chain. This gave us a swing circle that would keep us clear from sharp cliffs on the one side, and the city key on the other side. In the beginning I was a bit nervous being anchored in so much wind, and I slept out in the cockpit, so I would be alert if anything happened on the deck. Of course our trusty Excalibur (the nickname for our 40 kg Rocna anchor) held. At five in the morning we had a sudden shift in wind direction, just as predicted by the GRIB file weather forecast. I have never seen a wind shift like this in my life. Rather than gently brining the boat around the swing circle to the new location, the wind made a sudden shift, and we floated literally straight over our anchor to face the new wind direction. During this wind shift, the wind was a steady 5 Beaufort, and the only parameter changing the wind direction. Any anchor will have a hard time when suddenly yanked, in the opposite direction of how it is buried. It took Excalibur only 20 meters of dragging over the bottom to bury itself and renew his unrelenting grip at the sea bottom. Once Excalibur was settled we did not drag a single centimeter, which we could easily verify as the stern of SaltyPaws had drifted quite close to some jerry cans, that marked the unused moorings of some of the local vessels.

When we spotted a break in the wind (5 instead of 7 Beaufort) we made our way from Tinos to Paros, as we felt we needed to get some more kite surfing done. We found a sheltered bay where we could face the predicted 30 knots of wind, with gusts predicted to be more. This weather forecast was remarkably accurate. Once day we went kiting out on the 6 and the 8 m2 kites, and we stopped when I felt overpowered on my 132 m twin-tip on the 6m2. The next day the wind remained at this level, and it was too strong for us to kite even on the smallest kites. This blow set a new record for us as we recorded at times 44 knots of wind. This corresponds to 9 Beaufort, and if you want to know how strong this is, just stick your head out of the car window when you are driving 80 kilometers per hour (on the GPS that is, more closely to 90 on the odometer).

The trusty Excalibur lived up its name, and even the 44 knots thrown at it could not make its dead rip to the soil relent. We removed the Bimini top of the boat, to reduced the windage, and also the noise created by the flapping of the Bimini. A short dinghy ride to shore, in the sheltered bay would still soak you in salt water, as the waves seemed to build up sizable even in a very short fetch. Our 14 mm nylon bridle lines, ended up as 12 mm nylon lines when the storm had finally subsided. I always knew that the bridle lines would be the weak point in our anchor set-up, however this is by design. One function of the bride is shock absorption, and this typically not handled well by anchor chains, or ropes the size of your arm. Our bridle strategy is to replace it frequently, to walk the narrow line between maintaining enough flexibility in the system and ensuring it is strong enough to face up to its tasks. after just 3 months of sailing, the first anchor bridle is now relegated to less demanding duty. So far, the only one to dislodge excallibur's relentless grip on the sea bottom is Arthur, our trusty winch.



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