Re: [PCW] new member
Hello Robert and Jonah,
My concern with a low bridging deck is not the fact that it is low, but is
it strong enough to withstand pounding.
In certain sea state conditions, that can even occur on lakes, short, steep
swells will lift the boat up and it will drop back down causing it to slam
against the water. This consistent lifting up and slamming down is called
pounding. Constant pounding can be traumatizing until you get used to it,
but it should not damage a well built power catamaran. It should be hoped
that the designer and builder have done their jobs and the boat is built
strong enough to resist this constant pounding over the lifetime of the
boat.
The pounding noise doesnt always come from the bridge deck slamming down
into the water. Often it is a wave passing at an angle between the hulls
and slapping into the inside of the leeward hull. This vertical surface
acts like a piano sounding board transmitting the noise up into the bridge
deck and although the noise is loud it is unlikely to cause any damage to a
well constructed hull. If you do get into a prolonged heavy pounding
situation, then once you get to a calm anchorage, it would be a good idea to
do an underneath inspection for any stress cracks.
It doesnt necessary follow that the bridge deck being low to the water will
pound more. If the deck is low to the water it wont have so far to fall.
Other considerations come into play such as the weight of the boat and the
amount of buoyancy in the hulls and how far forward it extends to support
the weight. Adding bulb bows helps to improve the inherent lack of forward
buoyancy in catamaran hulls. Having said that I believe a 4 height
underneath at the bow sloping back to 3 for the final > of the length to
the transoms are safe numbers to have. Our ocean designed cruising cats
have an underneath clearance of 5 6 at the bow down to 4 at the transom.
Its a serious misconception that bay cruising or coastal cruising is safer
than going offshore. More boats get into more trouble along the coast than
they do offshore and thats not because there are more of them. It is due
to ocean swells coming up against a shallowing bottom that forces the wave
energy up to their cresting and breaking point resulting in breaking
confused seas. In deep offshore water the same waves may be just big
rollers that give you a big lift but generally dont break. This is why the
Navy will often leave a safe harbor and head out to deep water if a big
storm or hurricane threatens.
Cheers,
Captain Graham Pfister
President & Principle Designer
TrawlerCat Marine Designs
http://www.trawlercatmarine.com/ www.trawlercatmarine.com
-----Original Message-----
From: power-catamaran-bounces@lists.samurai.com
[mailto:power-catamaran-bounces@lists.samurai.com] On Behalf Of
power-catamaran-request@lists.samurai.com
Sent: Sunday, January 17, 2010 9:00 PM
To: power-catamaran@lists.samurai.com
Subject: Power-Catamaran Digest, Vol 57, Issue 14
Send Power-Catamaran mailing list submissions to
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Today's Topics:
- Re: new member. (leaper4me@aol.com)
- Re: new member. (leaper4me@aol.com)
Message: 1
Power-Catamaran Mailing List
Message: 2
Date: Sun, 17 Jan 2010 14:38:15 EST
From: leaper4me@aol.com
To: power-catamaran@lists.samurai.com
Subject: Re: [PCW] new member.
Message-ID: 1a9f1.29f07829.3884c127@aol.com
Content-Type: text/plain; charset="us-ascii"
In a message dated 1/17/2010 2:37:36 P.M. Eastern Standard Time,
leaper4me@aol.com writes:
Thank you for the welcome. Sorry it took me a while to reply.
We love the Endeavour 48, In fact at the 2008 Trawlerfest in Solomons, MD
we spent so much time on it that we were afraid they were going to charge
us a loitering fee. The only thing that concerns us is that afterward we
have had several people, some competitors but some without any interest in
what we ultimately decide to buy, describe the Endeavour 48 it as a "bay
boat".
When I ask what they meant the reply I got was that the bridgedeck
clearance was insufficient for open water passages through the Caribbean
and possibly beyond and better suited for fairly protected waters.
We would love to hear your thoughts on this as well as what you like about
your beautiful boat as well as anything you would like to change.
Thanks
Robert
In a message dated 1/7/2010 4:10:52 P.M. Eastern Standard Time,
jonah@northrock.bm writes:
Robert,
we are the owners of an endeavour 48. (link below)
Happy to answer any questions that you may have
Jonah.
www.jonah-art.com
www.jonahs-whale.com
Power-Catamaran Mailing List
Power-Catamaran Mailing List
Power-Catamaran Mailing List
End of Power-Catamaran Digest, Vol 57, Issue 14
Power Catamaran Members,
Yes, Low bridging tunnels can be disadvantage and
very noisy and
when the vessel is not well built, dangerous, as mentioned in the post
below.
It is quite difficult to design a true asymmetrical semi-planning hull,
where the entrance is fine, the
forward centre section a bit bulbous and therefore lifts the hulls with the
end section around 60% flat and planning.
When you get that right, as in cases with Wright and Lavranos, then things
come into true perspective of how a smooth stable catamaran should react in
all kinds of seas, which then also includes all the economic benefits.
Regards,
Tim Jordaan Aventure Power Catamaran
-----Original Message-----
From: power-catamaran-bounces@lists.samurai.com
[mailto:power-catamaran-bounces@lists.samurai.com] On Behalf Of Graham
Sent: 18 January 2010 21:05
To: power-catamaran@lists.samurai.com
Subject: Re: [PCW] new member
Hello Robert and Jonah,
My concern with a low bridging deck is not the fact that it is low, but is
it strong enough to withstand pounding.
In certain sea state conditions, that can even occur on lakes, short, steep
swells will lift the boat up and it will drop back down causing it to slam
against the water. This consistent lifting up and slamming down is called
pounding. Constant pounding can be traumatizing until you get used to it,
but it should not damage a well built power catamaran. It should be hoped
that the designer and builder have done their jobs and the boat is built
strong enough to resist this constant pounding over the lifetime of the
boat.
The pounding noise doesnt always come from the bridge deck slamming down
into the water. Often it is a wave passing at an angle between the hulls
and slapping into the inside of the leeward hull. This vertical surface
acts like a piano sounding board transmitting the noise up into the bridge
deck and although the noise is loud it is unlikely to cause any damage to a
well constructed hull. If you do get into a prolonged heavy pounding
situation, then once you get to a calm anchorage, it would be a good idea to
do an underneath inspection for any stress cracks.
It doesnt necessary follow that the bridge deck being low to the water will
pound more. If the deck is low to the water it wont have so far to fall.
Other considerations come into play such as the weight of the boat and the
amount of buoyancy in the hulls and how far forward it extends to support
the weight. Adding bulb bows helps to improve the inherent lack of forward
buoyancy in catamaran hulls. Having said that I believe a 4 height
underneath at the bow sloping back to 3 for the final > of the length to
the transoms are safe numbers to have. Our ocean designed cruising cats
have an underneath clearance of 5 6 at the bow down to 4 at the transom.
Its a serious misconception that bay cruising or coastal cruising is safer
than going offshore. More boats get into more trouble along the coast than
they do offshore and thats not because there are more of them. It is due
to ocean swells coming up against a shallowing bottom that forces the wave
energy up to their cresting and breaking point resulting in breaking
confused seas. In deep offshore water the same waves may be just big
rollers that give you a big lift but generally dont break. This is why the
Navy will often leave a safe harbor and head out to deep water if a big
storm or hurricane threatens.
Cheers,
Captain Graham Pfister
President & Principle Designer
TrawlerCat Marine Designs
http://www.trawlercatmarine.com/ www.trawlercatmarine.com
-----Original Message-----
From: power-catamaran-bounces@lists.samurai.com
[mailto:power-catamaran-bounces@lists.samurai.com] On Behalf Of
power-catamaran-request@lists.samurai.com
Sent: Sunday, January 17, 2010 9:00 PM
To: power-catamaran@lists.samurai.com
Subject: Power-Catamaran Digest, Vol 57, Issue 14
Send Power-Catamaran mailing list submissions to
power-catamaran@lists.samurai.com
To subscribe or unsubscribe via the World Wide Web, visit
http://lists.samurai.com/mailman/listinfo/power-catamaran
or, via email, send a message with subject or body 'help' to
power-catamaran-request@lists.samurai.com
You can reach the person managing the list at
power-catamaran-owner@lists.samurai.com
When replying, please edit your Subject line so it is more specific than
"Re: Contents of Power-Catamaran digest..."
Today's Topics:
- Re: new member. (leaper4me@aol.com)
- Re: new member. (leaper4me@aol.com)
Message: 1
Power-Catamaran Mailing List
Message: 2
Date: Sun, 17 Jan 2010 14:38:15 EST
From: leaper4me@aol.com
To: power-catamaran@lists.samurai.com
Subject: Re: [PCW] new member.
Message-ID: 1a9f1.29f07829.3884c127@aol.com
Content-Type: text/plain; charset="us-ascii"
In a message dated 1/17/2010 2:37:36 P.M. Eastern Standard Time,
leaper4me@aol.com writes:
Thank you for the welcome. Sorry it took me a while to reply.
We love the Endeavour 48, In fact at the 2008 Trawlerfest in Solomons, MD
we spent so much time on it that we were afraid they were going to charge
us a loitering fee. The only thing that concerns us is that afterward we
have had several people, some competitors but some without any interest in
what we ultimately decide to buy, describe the Endeavour 48 it as a "bay
boat".
When I ask what they meant the reply I got was that the bridgedeck
clearance was insufficient for open water passages through the Caribbean
and possibly beyond and better suited for fairly protected waters.
We would love to hear your thoughts on this as well as what you like about
your beautiful boat as well as anything you would like to change.
Thanks
Robert
In a message dated 1/7/2010 4:10:52 P.M. Eastern Standard Time,
jonah@northrock.bm writes:
Robert,
we are the owners of an endeavour 48. (link below)
Happy to answer any questions that you may have
Jonah.
www.jonah-art.com
www.jonahs-whale.com
Power-Catamaran Mailing List
Power-Catamaran Mailing List
Power-Catamaran Mailing List
End of Power-Catamaran Digest, Vol 57, Issue 14
Power-Catamaran Mailing List