Current location for King Malu

Sunday, 15 April 2012

Return from Beirut

116 nautical miles
One of the things we have been trying to do is work out the best way for route planning, specifically route planning relating to wind conditions. When we are sailing in the locality of land we usually use windguru.gz or, however for longer passages Tim has made in the past we used

Passage Weather shows maps of different areas of the world. The trouble is for short passages, the maps are not very detailed. For instance, the largest scale map of our area of the Mediterranean shows the passage from Beirut to Larnaca as a very small part of the map. (shown right the passage as a red arrow).
I don't know where I saw it recommended, but I saw on one of the forums I read. The cost for the basic option is quite reasonable at €19/year so we decided to give it a try. With the basic package you can set start and end waypoints and date/time of passage. This is useful as you can play 'what if' scenarios, changing the departure time to see how it affects the passage. 
PredictWind will then map out routes for either the fastest or greatest comfort. They also have four different weather algorithms - based on GFS or CMC and basic or Predict Wind modified. We tried the default, which is the Predict Wind modified. You can then play the scenario and watch the wind conditions change as you move along the route. On the whole we thought the red CMC was a more likely route and so I plotted three 'weather' waypoints into our chart plotter and created a route for the autohelm to follow.

We left Beirut a little earlier than expected, around 16:00 rather than the 18:00 we had plotted, but found the route almost exactly correct, except our boat speed was faster than they predicted. This was not surprising since you really have to put in boat and wave polars to Predict Wind for it to calculate correctly. We will do this next time.

The passage back was great. I (Richard) didn't get seasick at all and so it was very enjoyable. Tim and I are complementary skilled and learning from each other. Tim has been sailing on the ocean since he was a kid and so his seamanship is very much better than mine, but my reading of the navigation systems is something I am very comfortable with - years ago I even wrote the algorithm to convert 'Digital Chart of the World' to a GIS format for a group I was working with in the USA. 

The only time Predict Wind didn't get it right was coming into the Larnaca Bay itself. The wind was about 11-12 knots 120 starboard. The clouds were very low and Tim and I both clipped on as his experience said that we were in for some squalls... the first one touched 25 knots, which is quite an increase on 11 knots in less than 10-15 seconds. 

This hadn't been predicted so I called up Cyprus Radio on the marine band radio to see if the forecast had changed while we were sailing. While doing this a second squall came thought at 28 knots. Cyprus Radio said the forecast was for winds from the direction we were observing but beaufort 3-4, which was very much less than the beaufort 6 we were actually experiencing while I talked to them on the radio!

We arrived back safely and then went through the check-in procedure at Larnaca: Marine Police for Immigration, Medical Doctor, Customs and finally Marina (which we actually did the following morning).

All in all a very good maiden voyage for us in King Malu.

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