The Wind or ‘vind’

Saturday March 04th, 2017

02:25 You don’t really sleep when the wind blows 25/30 overnight. You close your eyes and a noise gets your attention and you are in the cockpit trying to identify the offending source. The wind is a powerful source of energy. The wind at 15m/s or about 30KTS has a force of around 135 N/m2. The wind blowing at 15KTS has a force, load or pressure of about 34 N/m2. So physics fans,  the wind blows twice as fast but the force of the wind is 4 times as strong. One only needs to try to sleep on FRACAS to validate this. We will get through the night, but the forecast is for this to blow like this for a couple more days before it diminishes to 20.

05:30 I guess I am up for the day now. I was up a couple of times since the last entry everything still ok. The wind is so gusty that Fracas continues to do the tango with the anchor. But so far she is maintaining her distance to where we put the anchor so that is good. Every time I think or say that I think the wind is quieting a little it pipes up with another grunt of wind. The maximum gust this session was over 33 KTS.

It is a little more relaxing now that I have the chart plotter repeating on the TV in the salon. I can sit out of the wind and monitor stuff, you know what Captains do. If you squint you can see that the wind at the time was almost 24KTS. My reference waypoint out near where the anchor lives is 160 feet out. I have 100 feet of chain off the bow with 16 to 12 feet from the roller to the bottom with the tide. The engineers say that anything more than 6 to 1 anchor rode scope is a waste. So we have Fracas at a little more than 5 to 1 and she’s holding. The GPS antenna is at the stern so we have to add the length of the boat to the bow roller or about 45 feet. So, my reference point is out there 10 or 15 feet beyond the anchor. So I keep a weather eye on the Dist to Dest which shows 156 to 160 feet and has done so all night.

You can see from the plot that I added about 25 feet of chain when the blow started and we’ve plotted a pretty localized trace during the night, all good. It looks like we have wandered but it is well within the error of the system, and the scale is very tight. The distance between the – and + at the bottom of the screen is 20 feet. I’ll bring in the 25 feet of chain when this blow settles on Monday to keep our swing under control in this tight anchorage.

When the wind clocks to the east as this settles out the ‘yellow’ Florida boat 75 feet off my starboard beam will be an issue. He will likely be right over my chain. I gave him the stare yesterday but to no avail… perhaps it will come to rum or cannon fire or perhaps both.

I look forward to daylight when I can safely get on deck and fix a clanger on the main mast. Something slacked and started clanging but not to the level of immediate repair. So much easier in the light.

It is now just after 06:00 and the latest solid gust ramped up to over 30 again. This air is in a hurry to get somewhere and do it’s part in balancing out the world. The butterfly effect?

Leave a Reply

This site uses Akismet to reduce spam. Learn how your comment data is processed.