Lightning-motorsailers-passagemakers
trawlers are very efficient, perhaps not as
efficient as even the worst of
sailboats, but even big trawlers can move through
the water with an
amazingly low amount of horsepower. They don't move
fast, but they move.
Sails do generate horsepower, and use no
electricity.
Ken - I think the 'missing link' you are searching for
is two fold. First, although a 45-foot sailboat may
have a 50hp engine, it's probably only using under
10hp or so to move through flat water at hull speed. I
have no idea of the wind/hp mathmatical formula
either, but sails are not producing 50hp. The old
British rule for sizing an engine for a sailboat was
1-hp per long-ton of displacement. If your 100-ton
boat was built 50 years ago as an auxilliary sailboat,
it would have the equivilent of a Perkins 4-236 (80hp)
in it - barely enough for in-har. You gotta love the
Brits!
Second, sailboats can sail close to the wind because
there is "lift" generated by the sail shape AND the
keel shape.
With sails, however, your Nordhavn would drift
slightly faster and collide with whatever eventual
landmass is downwind slightly sooner. I'm not sure if
that's a good or a bad thing.
BTW - Nice website (nordhavn68.com)
Peter
=======================
Peter Pisciotta
415-902-8439
As an indirect offshoot of this discussion, I was just googling compressed
air starting systems. As people have said, the obvious answer is to "get the
diesel engine running", which can be tricky without batteries. My current
thinking is that I'll have plenty of compressed air on the boat (scuba
tanks, air horn), and although I haven't found it yet I'm confident such
systems exist. It might be that a cheap adapter stored in a closet, provides
a simple way to get the diesel engine turning.
John Marshall raised the question of electronic engines. I raised this issue
with Steve Shultz of Lugger a few months back. My Nordhavn 62 had a
"mechanical engine," and was much simpler, hence more reliable. The new
Lugger engines, and I suspect all new diesel engines, have computers and
electric fuel pumps. I had Steve walk me through a zero-electricity
scenario, and it wasn't pretty. The conversation wasn't recent so I don't
recall the details, but I think we found a way to get around the electric
fuel pumps, and Steve claimed that the engines WOULD run without the
computers, but very poorly. I didn't like the look in his eye as he said it,
and suspected that if the need ever arose, I wasn't going to like
discovering what "running poorly" meant. I bought backup computers for each
of my engines (I think they were like $1,800 each! and are specifically
programmed for the engine they apply to) I did ask Steve whether or not it
was possible to order a "good old fashioned mechanical engine" and he said
that the computers were now mandatory for emissions compliance.
-Ken W
Nordhavn68.com
-----Original Message-----
From: passagemaking-under-power-bounces+kenw=seanet.com@lists.samurai.com
[mailto:passagemaking-under-power-bounces+kenw=seanet.com@lists.samurai.com]
On Behalf Of bob england
Sent: Wednesday, March 21, 2007 12:23 AM
To: passagemaking-under-power@lists.samurai.com
Subject: Re: [PUP] Passagemakers under power, and sails
A nordy68 is gonna drift, not sail. It has a lot of windage. If I can't make
a diesel engine run I'm a Du#$%ss and have no business being anywhere
offshore in a diesel powered boat.
Thanks, Ken. Sounds like you had the exact discussion with engine
guys that I was about to start. Result... it ooks like a spare
computer (pre-programmed) and a spare electric fuel pump have just
joined my spares list. Not just from a lightning perspective (object
of this thread) but because anything either electronic or with a
motor WILL fail. It's just a matter of time.
John
On Mar 21, 2007, at 8:04 AM, Ken Williams wrote:
As an indirect offshoot of this discussion, I was just googling
compressed
air starting systems. As people have said, the obvious answer is to
"get the
diesel engine running", which can be tricky without batteries. My
current
thinking is that I'll have plenty of compressed air on the boat (scuba
tanks, air horn), and although I haven't found it yet I'm confident
such
systems exist. It might be that a cheap adapter stored in a closet,
provides
a simple way to get the diesel engine turning.
John Marshall raised the question of electronic engines. I raised
this issue
with Steve Shultz of Lugger a few months back. My Nordhavn 62 had a
"mechanical engine," and was much simpler, hence more reliable. The
new
Lugger engines, and I suspect all new diesel engines, have
computers and
electric fuel pumps. I had Steve walk me through a zero-electricity
scenario, and it wasn't pretty. The conversation wasn't recent so I
don't
recall the details, but I think we found a way to get around the
electric
fuel pumps, and Steve claimed that the engines WOULD run without the
computers, but very poorly. I didn't like the look in his eye as he
said it,
and suspected that if the need ever arose, I wasn't going to like
discovering what "running poorly" meant. I bought backup computers
for each
of my engines (I think they were like $1,800 each! and are
specifically
programmed for the engine they apply to) I did ask Steve whether or
not it
was possible to order a "good old fashioned mechanical engine" and
he said
that the computers were now mandatory for emissions compliance.
-Ken W
Nordhavn68.com
-----Original Message-----
From: passagemaking-under-power-bounces
+kenw=seanet.com@lists.samurai.com
[mailto:passagemaking-under-power-bounces
+kenw=seanet.com@lists.samurai.com]
On Behalf Of bob england
Sent: Wednesday, March 21, 2007 12:23 AM
To: passagemaking-under-power@lists.samurai.com
Subject: Re: [PUP] Passagemakers under power, and sails
A nordy68 is gonna drift, not sail. It has a lot of windage. If I
can't make
a diesel engine run I'm a Du#$%ss and have no business being anywhere
offshore in a diesel powered boat.
Passagemaking Under Power and PUP are trademarks of Water World
Productions, formerly known as Trawler World Productions.
To be removed from the PUP list send an email with the
subject "unsubscribe" (no quotes) to the link below:
mailto:passagemaking-under-power@lists.samurai.com
Passagemaking-Under-Power Mailing List
Thanks, Ken. Sounds like you had the exact discussion with engine
guys that I was about to start. Result... it ooks like a spare
computer (pre-programmed) and a spare electric fuel pump have just
joined my spares list. Not just from a lightning perspective (object
of this thread) but because anything either electronic or with a
motor WILL fail. It's just a matter of time.
John
On Mar 21, 2007, at 8:04 AM, Ken Williams wrote:
As an indirect offshoot of this discussion, I was just googling
compressed
air starting systems. As people have said, the obvious answer is to
"get the
diesel engine running", which can be tricky without batteries. My
current
thinking is that I'll have plenty of compressed air on the boat (scuba
tanks, air horn), and although I haven't found it yet I'm confident
such
systems exist. It might be that a cheap adapter stored in a closet,
provides
a simple way to get the diesel engine turning.
John Marshall raised the question of electronic engines. I raised
this issue
with Steve Shultz of Lugger a few months back. My Nordhavn 62 had a
"mechanical engine," and was much simpler, hence more reliable. The
new
Lugger engines, and I suspect all new diesel engines, have
computers and
electric fuel pumps. I had Steve walk me through a zero-electricity
scenario, and it wasn't pretty. The conversation wasn't recent so I
don't
recall the details, but I think we found a way to get around the
electric
fuel pumps, and Steve claimed that the engines WOULD run without the
computers, but very poorly. I didn't like the look in his eye as he
said it,
and suspected that if the need ever arose, I wasn't going to like
discovering what "running poorly" meant. I bought backup computers
for each
of my engines (I think they were like $1,800 each! and are
specifically
programmed for the engine they apply to) I did ask Steve whether or
not it
was possible to order a "good old fashioned mechanical engine" and
he said
that the computers were now mandatory for emissions compliance.
-Ken W
Nordhavn68.com
-----Original Message-----
From: passagemaking-under-power-bounces
+kenw=seanet.com@lists.samurai.com
[mailto:passagemaking-under-power-bounces
+kenw=seanet.com@lists.samurai.com]
On Behalf Of bob england
Sent: Wednesday, March 21, 2007 12:23 AM
To: passagemaking-under-power@lists.samurai.com
Subject: Re: [PUP] Passagemakers under power, and sails
A nordy68 is gonna drift, not sail. It has a lot of windage. If I
can't make
a diesel engine run I'm a Du#$%ss and have no business being anywhere
offshore in a diesel powered boat.
Passagemaking Under Power and PUP are trademarks of Water World
Productions, formerly known as Trawler World Productions.
To be removed from the PUP list send an email with the
subject "unsubscribe" (no quotes) to the link below:
mailto:passagemaking-under-power@lists.samurai.com
Passagemaking-Under-Power Mailing List
Ken - I think the 'missing link' you are searching for
is two fold. First, although a 45-foot sailboat may
have a 50hp engine, it's probably only using under
10hp or so to move through flat water at hull speed. I
Real hull speed at 1.34 times the waterline length probably takes all 50
hp, but if not at least about 3/4 of the 50 or about 38 hp.
At 1.00 times the WLL, it might take about 10 hp.
The curve of effort required to get above 1.00/1.10 is quite steep.
The use of 100 to 150 hp engines in boats of about 45 feet provides
considerable power to overcome the effects of contrary wind and waves,
but will not generally make a displacement one go faster than 1.34 times
the WLL. Or about 8 knots.
Long range economy is generally not above 1.1 times the WLL.
There are a lot of minor variables in all of the above.
Mike
Capt. Mike Maurice
Beaverton Oregon(Near Portland)
programmed for the engine they apply to) I did ask Steve whether or not it
was possible to order a "good old fashioned mechanical engine" and he said
that the computers were now mandatory for emissions compliance.
It is my understanding that the Iveco 150? hp engine that Seahorse
Marine is using is not electronic controlled and is Tier 3 compliant.
Bill Kimley follows this forum, perhaps he will provide some comment.
Mike
Capt. Mike Maurice
Beaverton Oregon(Near Portland)
Another way: Spring starters: http://www.springstarter.com/
Just pull the 'starter' coard a few times to build up enough energy to start
the motor.
-al-
----- Original Message -----
From: "Ken Williams" kenw@seanet.com
To: "'Passagemaking Under Power List'"
passagemaking-under-power@lists.samurai.com
Sent: Wednesday, March 21, 2007 8:04 AM
Subject: Re: [PUP] Passagemakers under power, and sails
As an indirect offshoot of this discussion, I was just googling compressed
air starting systems.