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Lexington - 3/8/17. 3 am. 8°. 54' south. 100°. 11' west



So it is my watch again. Getting up at 3 sucks but seeing the sunrise is a good reward. We have had a good night with southeast winds 10-14 knots. Our boat speed is high 6's. My guess is the air temperature is 78-80 but that is a guess. All in all, very pleasant.
We are sailing great for my boat. We are trying to be conservative and not break stuff but we are usually 6 knots or above. For a 10 hour period during the day yesterday, we averaged 6.1 knots. The hooker is that we are in with a bunch of good boats and good sailors. When I looked at the position report just issued there just a few boats further from the destination than we were. One of those broke their mast and is catching up and another delayed their start to fix a generator problem. When we were motoring a lot at first we ran at around 1,400 rpm which resulted in around 4 knots. We have a computer in the system that calculates miles per gallon of fuel. At that rate we consumed 0.5 gallons an hour. If we doubled our fuel consumption to 1 gallon an hour we would only increase our speed by 50%. Now for our excuses!
With boats there are some limitations on speed. For monohulls there is the hull speed which is determined by the length of your waterline (how long is the section of boat at the surface of the water). Sail boats (most) are displacement boats meaning that they move thru the water not over the water. A boat that moves over the water is a planing boat. When it gets enough power it will come up out of the water and skim along the top. The next step up is a hydroplaning boat, like the America's Cup Catamarans. They literally hydroplane the whole hull out of the water. Each of these steps reduces friction and increases speed. My boat has a speed above which you can not go called the hull speed which is calculated as something like 1.34 times the square root of the length of water line. You have to realize that I have no Google... this is all from memory. Do not take this stuff for absolutely correct. If I quadruple the horse power of my engine I would not increase my speed above the hull speed. Increased power just pushes a bigger and bigger bow wave thereby keeping the speed down. Back to the other boats, there are a lot of longer boats ahead of us for multiple reasons, one of which is hull speed. Catamarans generally sail faster unless they are weighted down tremendously.
Zeeland, Tulla Mhor, Timshel, Owl, North, and Taistealai are in our size group. Unfortunately of that group we are bringing up the rear. At times we have done better. I think we may sail a little more aggressively at night than some others. Four of those 6 boats are sailed by husband and wife crews. Generally those boats will reduce sail at night to be safer and easy for one person to handle alone at night. Hopefully we might move more into the pack over the next 15-20 days. We definitely have time to improve.
This is getting a little too long and boring. Most of you real sailors all know this stuff but a lot of people reading this are not that versed with sailing. Give me your comments. Is my content boring or not?
Best wishes to all. Tolerate me. These post are how I fill my watch and get to talk to someone even though you cannot say shut up!  Bob

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