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Passagemaker attributes - pilothouse location

T
Truelove39@aol.com
Fri, Jan 23, 2009 2:00 PM

Hi  Ken,

Thanks  for sharing your exp. with the 62. IMHO Nordys best (after the 46) -
a  great boat and likely patterned after our Skookum 53 :-)

You  are right about the 1/3 of the way from the stern - that's the magic 28%
that  Beebe stated as the ideal location for the paravanes. I  called it the
"center of pitch" in my original post for clarity; it is really  the Center of
Flotation (CF).

Question - how does your 68 compare to the 62 in a head  sea?

Regards,

John
"Seahorse"

I  probably shouldn't post anything, because I'm not sure I'm  correctly

following the discussion, but as a former Nordhavn 62 owner I can  definitely
say that the pilothouse sure seemed to be in the perfect location.  It is at
the center pivot point to the boat. We were in wild seas on  several
occasions, and you could clearly see where the center of the boat  was. The
closer you were to the center, the more stable you felt. On the N62  this
meant the pilot house, or the aft deck behind the pilot house. It also  meant
the main salon. Interestingly, the pivot point didn't seem to be at  the
middle of the length of the boat, but about 1/3rd of the way from the  back
of the boat. My interpretation has always been (and, correct me if  I'm
wrong), that this is because the center of the vessel (the center  of
gravity) is at the center of the vessel's weight, not its' length, and  that
with the engines towards the back of the boat on the N62, the center  of
gravity is aft of midship.

The other nice thing about the  pilothouse location on the N62 was the huge
bow in front of the pilothouse.  Rarely did waves coming over the bow hit the
windshield. In the pilothouse,  we were a good 25 feet back from the bow.
This also gives the N62 a HUGE bow  which is perfect for tenders.

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Hi Ken, Thanks for sharing your exp. with the 62. IMHO Nordys best (after the 46) - a great boat and likely patterned after our Skookum 53 :-) You are right about the 1/3 of the way from the stern - that's the magic 28% that Beebe stated as the ideal location for the paravanes. I called it the "center of pitch" in my original post for clarity; it is really the Center of Flotation (CF). Question - how does your 68 compare to the 62 in a head sea? Regards, John "Seahorse" >I probably shouldn't post anything, because I'm not sure I'm correctly following the discussion, but as a former Nordhavn 62 owner I can definitely say that the pilothouse sure seemed to be in the perfect location. It is at the center pivot point to the boat. We were in wild seas on several occasions, and you could clearly see where the center of the boat was. The closer you were to the center, the more stable you felt. On the N62 this meant the pilot house, or the aft deck behind the pilot house. It also meant the main salon. Interestingly, the pivot point didn't seem to be at the middle of the length of the boat, but about 1/3rd of the way from the back of the boat. My interpretation has always been (and, correct me if I'm wrong), that this is because the center of the vessel (the center of gravity) is at the center of the vessel's weight, not its' length, and that with the engines towards the back of the boat on the N62, the center of gravity is aft of midship. The other nice thing about the pilothouse location on the N62 was the huge bow in front of the pilothouse. Rarely did waves coming over the bow hit the windshield. In the pilothouse, we were a good 25 feet back from the bow. This also gives the N62 a HUGE bow which is perfect for tenders. **************A Good Credit Score is 700 or Above. See yours in just 2 easy steps! (http://pr.atwola.com/promoclk/100000075x1215855013x1201028747/aol?redir=http://www.freecreditreport.com/pm/default.aspx?sc=668072%26hmpgID=62%26bcd=De cemailfooterNO62)
KW
Ken Williams
Fri, Jan 23, 2009 2:38 PM

John (Seahorse) said: "... Question - how does your 68 compare to the 62 in
a head  sea?..."

It's impossible to really compare the two boats accurately. We sold our 62
nearly five years ago, and I have such fond memories of it, that it is
difficult to be objective. But, I'll do my best...

The N68 is amazing going into head seas. I've never seen a boat take head
seas as well, and I have a few theories as to why:

  • The "center of pitch" on the N68 is closer to the middle. This helps keep
    the bow down. Because the 62 has it's fulcrum point further aft, the long
    bow has to move up and down more (imagine a teeter-totter, with an off
    center fulcrum).

  • The 62 has a bulbous bow, and the 68 does not. The bulbous bow on the 62
    is an older technology than what is being used today, and has a tendency to
    slap the water on re-entry.

  • Weight is certainly a factor in the difference in the ride. The 62 weighs
    sixty tons, whereas the 68 weighs over 100 tons.

  • The twin engines in my 68 may be a factor. I've never had the boat slow
    down when punching into head seas, unless I slowed it down, or a current
    did. I have plenty of power available, and the twin props take a big bite at
    the sea.

Despite my saying that it is impossible to directly compare the boats, we're
about to do it! Two 62s (Grey Pearl and Seabird) as well as my 68 (Sans
Souci) will be running the Bering Sea, backwards, this July. We'll be
battling a head sea, and head wind, side by side for a couple thousand
miles. Overall we'll be running together for over five thousand miles. My
guess is that by the time we arrive in Japan we'll have some good
quantitative information about how the boats compare in every type of
condition imaginable. I'm just hoping that my stomach fares as well as
either model of boat.

Ken Williams
Sans Souci, Nordhavn 68
www.kensblog.com

John (Seahorse) said: "... Question - how does your 68 compare to the 62 in a head sea?..." It's impossible to really compare the two boats accurately. We sold our 62 nearly five years ago, and I have such fond memories of it, that it is difficult to be objective. But, I'll do my best... The N68 is amazing going into head seas. I've never seen a boat take head seas as well, and I have a few theories as to why: - The "center of pitch" on the N68 is closer to the middle. This helps keep the bow down. Because the 62 has it's fulcrum point further aft, the long bow has to move up and down more (imagine a teeter-totter, with an off center fulcrum). - The 62 has a bulbous bow, and the 68 does not. The bulbous bow on the 62 is an older technology than what is being used today, and has a tendency to slap the water on re-entry. - Weight is certainly a factor in the difference in the ride. The 62 weighs sixty tons, whereas the 68 weighs over 100 tons. - The twin engines in my 68 may be a factor. I've never had the boat slow down when punching into head seas, unless I slowed it down, or a current did. I have plenty of power available, and the twin props take a big bite at the sea. Despite my saying that it is impossible to directly compare the boats, we're about to do it! Two 62s (Grey Pearl and Seabird) as well as my 68 (Sans Souci) will be running the Bering Sea, backwards, this July. We'll be battling a head sea, and head wind, side by side for a couple thousand miles. Overall we'll be running together for over five thousand miles. My guess is that by the time we arrive in Japan we'll have some good quantitative information about how the boats compare in every type of condition imaginable. I'm just hoping that my stomach fares as well as either model of boat. Ken Williams Sans Souci, Nordhavn 68 www.kensblog.com