The Henderson Bow

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Jul 3, 2006
108
Wildschut skûtsje Carcassonne
Hi Glenn,

It is easy to watch the evolution of the Hunter designs under your hand; your very distinctive "hollow-cheeked" bows mark all of the recent models you have drawn for them. Can you please share with us the process that took you to this design.

In my estimation, this fine entry combined with the broad stern sections that you have drawn, contributes so much to the motion comfort of my 49, and makes it such a fast boat. I have on many occasions exceeded the theoretical hull speed, often sailing in the area of 9.5 knots, and at times topping 10. I congratulate you on your wonderful design of the 49. To me it combines wonderful sea kindlieness and superb comfort in a very easy to sail vessel. I am fully confident that it will take me wherever I wish to go.

We are leaving in August on an open-ended exploration of the planet, and I am nearing completion of adding about 2,000 kilograms to the weight of the boat, with a 1225 Ah house bank, a generator, a 510 Watt solar array and wind generator on a subsiduary stern arch, a Hydrovane, a watermaker, three additional anchors from a 40kg Rocna on down, 150 metres of additional chain, and so on.

In the next few weeks, after I have finished these installations, I will see how sprightly she is on her new lines. She appears to be some 10 centimetres or so deeper in the water now than is her newly arrived unladen sister in the marina. Can you please tell me what the kilograms per centimetre of immersion is for the 49.
 

ghen

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Mar 15, 2009
104
2 216 St. Augustine
Michael,

The bow hollow reduces drag and minimizes pitching. Issac Newton taught us that "a particle of mass at rest wants to stay at rest". Once the particle is moving it is easier to move it more. As the bow enters still water, the narrow stem pushes the molecules of water aside. The hollow allows the molecules to gain intertia before the rest of the boat comes along and pushes them more. It takes energy to move the molecules from rest.

Kgs per Cm Immersion= 332

Have fun on your cruise!
 
Jun 2, 2004
5,802
Hunter 37-cutter, '79 41 23' 30"N 82 33' 20"W--------Huron, OH
Really, 150 metres of additional chain!? Where can you put that much chain, surely not all in the bow area? And if really 500 feet I guess I wonder why.
 
Jul 3, 2006
108
Wildschut skûtsje Carcassonne
Really, 150 metres of additional chain!? Where can you put that much chain, surely not all in the bow area? And if really 500 feet I guess I wonder why.
Ed,

100 metres of it is on the 40 kg Rocna and stowed in the bow's starboard chain locker, a further 25 metres is now on the 20 kg Delta with 80 metres of 19mm laid nylon in the bow's port chain locker. The remaining chain is in the transom locker with a FX-55 and a FX-37 and 200 metres of 19mm laid nylon as spare ground tackle and for use as stern anchor and/or stern ties as necessary.

The 150 metres weighs about 315 kilos, which on my boat is only about 2% of the displacement and very reasonable, while on yours it would be 5-6% of the displacement, and would not only be unreasonable, but also unnecessary.

As to why; yesterday we were anchored in 28 metres and with our 4-5 metre tidal range on the BC coast, that left us with barely a 3:1 scope. A long rode is useful here. In Patagonia, where we are heading, many of the deep narrow anchorages with their frequent williwaws, require long and beefy ground tackle and robust stern tie arrangements.
 
Jul 3, 2006
108
Wildschut skûtsje Carcassonne
Michael,

The bow hollow reduces drag and minimizes pitching. Issac Newton taught us that "a particle of mass at rest wants to stay at rest". Once the particle is moving it is easier to move it more. As the bow enters still water, the narrow stem pushes the molecules of water aside. The hollow allows the molecules to gain intertia before the rest of the boat comes along and pushes them more. It takes energy to move the molecules from rest.
Thank you Glenn for your wonderfully simple reply. This makes so much sense, I wonder why we don't see it applied more often.
Have fun on your cruise!
You bet we will. I've been dreaming of and planning for this since I bought my first sailboat in 1964. The reality of it is getting so close now, I can taste it; only 135 days to departure.
 

ghen

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Mar 15, 2009
104
2 216 St. Augustine
Michael,

I have been fantasizing lately myself. I was digging in a closet a few days ago and broke out my old sextant. I also had my old log books and charts. I just read a book "The Strormy Voyage of Father's Day" by Hugo Vihlen. It was about the record setting smallest boat (1.63 M) sailed across the Atlantic. Though his was understandably a more ardous trip than I care to make, he relayed a lot of the joys of being on the ocean that I remembered. I hope you get the same enjoyment. I live in Costa Rica most of the time and life is so much more real here. Very similar to cruising. It is a much more organic lifestyle. You know you are connected to the earth and sea and not just a particle of a synthetic world. Have fun!

Glenn Henderson
 
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