Year 5 Day 160 Slow And Easy
13 July 2012 | Sailing OffThe North Coast Of Australia
Dave/Weather: Mostly Sunny
The winds have been more consistent during these last 24 hours. However, they remain light averaging only about 12 knots. Did you know that the world wide average for wind speed is just 12 knots? Yep, it's true. Thus, I guess you could just call this day an "average" day. However, with this "average" day comes what is for us below average sailing speed. During our 4.5 years of cruising, we have averaged about 6.5 knots. Right now, 6.5 knots would seem like speeding! Mind you, I am not complaining. This passage has been wonderful with fair skies most of the time, calm seas and winds that at least keep us moving forward. You really can't ask for much more than that!
During this passage we have only had to dodge one set of pretty paltry squalls. The rest of the time we have had no rain, heavy seas, nor high winds. Sounds pretty sweet to me!
We are less than a day away from rounding Cape Don and entering the Gulf of Van Diemen. The entrance of the gulf is the second "gate" in this passage to Darwin. The first "gate" was the Gulf of Carpentaria. As you know when we rounded Cape York and headed for the Gulf of Carpentaria, the "gate" was closed due to high winds and rough seas. We had to wait a number of days before the winds abated and the "gate" was opened.
The "gate" at Cape Don is not so much controlled by winds as it is by tides. There is a tidal current that flows into and out of the Gulf of Van Diemen that can go up to 6 knots. Thus, you want to time your entrance to the gulf based on an in flowing tide. The general rule is to time your entrance based on the tides at Darwin and enter 4.5 hours before high tide at Darwin. The alternative rule is to enter the gulf on a flooding tide. Flooding tides flow south into the gulf.
Looking at the tide chart for Darwin, we should enter the gulf around 0845 tomorrow. However, based on the tide chart for Cape Don, the tide changes and starts to flood at 0644 tomorrow. Thus, it looks to me that we have about a 2 hour window to pass through this "gate" and enjoy the peak tidal currents flowing in our favor. I am going to try to time our arrival for about 0730 since there should be good light then. Many cruisers have to pull into Alcaro Bay, which is just before you reach Cape Don, and wait for the correct tidal situation (i.e., for an open "gate"). However, I believe we can adjust our speed a bit to get there without having to wait. We shall see
At 1230, our position was 10 46.0'S/133 32.0'E. We only made 133 nm with light winds that blew between 10 and 14 knots. We averaged about 5.5 knots for the day. Our course is 267 degrees True; our current speed is 4.5 knots. The winds are currently from the ESE and "blowing" 9.7 knots. Our apparent wind is 8.5 knots from 100 degrees from our port bow. The swells are from both the E and SE with respective heights of about 1 meter and respective periods of about 6 seconds. We are just "waltzing" along