[PUP] Med Bound 2007 Noon Report - June 18: Stabilizer problems

[Georgs Kolesnikovs]

Noon Report June 18, 2007

Position 34-51.5.N 50-25.4 W as of 12:00 Atlantic time (GMT - 3 hrs) 
Monday, June 18, 2007
Course 095 deg M
Speed 5.9 kts @ 1700 RPM
1,075 NM to go to Horta, Faial, Azores (59% of the way)
Distance made good past 24 hours:  147 NM (6.1 kts)
Distance made good since Bermuda: 743 NM (41% of the way)
Total fuel consumed (122.3 engine hours) 460 gals, average 3.8 GPH 
(incl. genset), fuel remaining 1020 gal. (fuel used/remaining: 
31%/69%)
Conditions: Wind 20-25 kts., swells 3-5 ft from 250 deg M, mostly 
cloudy with slight haze, visibility good.
Barometer 1020.3 mb and steady.
Sea water temp 74 deg F, air temp 81 deg F.
ETA Horta: June 25, 2007

What a difference a day makes!

As the Med Bound fleet was overtaken by low pressure overnight, 
chasing away yesterday's flat seas and clear skies, our winds and 
cloud cover increased. Seas have built slowly to 3-5 feet on the 
starboard quarter and looking around we see whitecaps everywhere. 
Bob says there's some rain to come, possible thunderstorms.  It was 
all quite comfortable until Judy awakened me mid-morning with a 
report that we had a stabilizer alarm.  "Probably no big deal," I 
thought, as I pulled myself out of bed and made my way to the 
pilothouse.  But investigation and trouble-shooting led to my 
preliminary diagnosis which was confirmed by Naiad: the starboard 
side potentiometer, which tells the system how that fin is 
positioned, has failed or malfunctioned.  If the system's  software 
doesn't know the position of the fin, it cannot position the fin 
correctly-and that was what the alarm was telling us.  What does this 
mean?   Bluewater's port side stabilizer fin is out of business.  We 
do not carry a spare potentiometer, so for the next 1,000 miles or so 
we're down to a single working stabilizer fin to keep us on the 
level.  The good news is that a stabilization system like ours is 
about 80% as effective on a single fin as on two.

Up on my soapbox for a minute.  If you've been to sea in a full 
displacement trawler like a Nordhavn, you know that good 
stabilization is a critical part of the equation.  Even without 
stabilizers, a vessel like ours is a most seaworthy creation.  It's 
not going to sink and it's not going to turn over.  But it will roll 
and roll and roll.  The roll is built right into the design, and 
nothing I've seen other than active fin stabilizers and their 
low-tech cousins, paravanes, can do much about that.

When we began rolling more than normal today after the port 
stabilizer went south, George asked seriously whether this boat would 
"turn over."  To owners like Judy and me, both of us sailors for more 
than 40 years, that seems an odd question-but to someone with a lot 
fewer sea miles it's a legitimate one that deserves an answer.  As I 
explained to George today, the short answer is, NO.  No Nordhavn has 
ever turned over at sea and it's most unlikely that one ever will. 
Chief designer Jeff Leishman can give you the technical side, but the 
truth is that stability is designed in from the keel up, and it's 
physically impossible for a vessel like this to turn over (that is, 
roll to port or starboard) and not recover.  By the very nature of 
her design and the laws of physics, the farther she rolls in one 
direction, the greater the resistance to rolling.  She'll roll, but 
she'll always resist the roll and come back in the other direction, 
rolling to the other side.  That very stability is what makes her an 
uncomfortable yacht when stabilization is lost.

The truth is that no Nordhavn has ever been lost at sea by sinking or 
"turning over".  That's just one of many reasons Judy and I own a 
Nordhavn and have enough confidence in the yacht to take her across 
an ocean!

Stabilization in an ocean-going trawler yacht is much more than a 
comfort issue.  In truth it's a safety issue as well.  Yes, a trawler 
yacht like Bluewater can go to sea without stabilization, but the 
crew aboard such a yacht will be many times less comfortable and runs 
a much greater risk of injury from being tossed about in a seaway. 
On the other hand, a well stabilized yacht allows crewmembers more 
comfort, better rest and more of it, especially in heavy weather.   A 
crew with injuries or exhausted from lack of rest is a crew on the 
verge of making mistakes!

As much as I love Bluewater's active fin stabilizers, I began this 
trip knowing that active fin stabilizers had been the Nordhavn 
Atlantic Rally's most troublesome mechanical system.  Crossing oceans 
is not for wimpy power boats or wimpy stabilizer systems.  In fact, 
it's my guess that a single ocean crossing aboard a trawler yacht 
probably subjects its active fin stabilization system to more stress 
than many stabilizer systems see in a lifetime.  That's one reason we 
outfitted Bluewater with a heavy-duty Naiad system designed for 
larger yachts than our 47 feet-but then ordered a backup system, 
paravanes, as well.   A paravane system requires a lot of rigging and 
it's not pretty to the eye of many owners, but as a backup 
stabilization system it has a lot going for it because it has no 
hydraulic, electrical, or electronic parts to break-the stabilization 
comes from towing heavy delta-wing paravanes through the water to 
resist rolling   Paravanes will definitely slow a yacht down when 
being used; our experience shows a speed loss of about 4/10 of a 
knot, something we do not experience with our Naiads.  But in most 
cases a more stable oceangoing yacht trumps a faster one.  So 
Bluewater continues on, confident that even if the other stabilizer 
packs it in, we'll have stabilization all the way to the Azores.  Our 
paravanes are stowed in fittings on our transom and our paravane 
poles were deployed in the ready position as we departed Bermuda, so 
we can launch paravanes in minutes if the need arises.

Our two companion yachts, the N55s Moana Kuewa and Salty Dawg, both 
have TRAC stabilizer systems, a brand favored by many Nordhavn 
owners.  My own stabilizer experience-virtually all of it-is with 
Naiad, and in building Bluewater my decision was to stick with what I 
know.  Over more than 15 years of owning Naiads on two yachts I've 
had few stabilizer problems.  Anytime I have had a problem, however, 
never once has Naiad failed diagnose the problem quickly and get me 
up and running in short order.  It my experience it all comes down to 
one man: Vic Kuzmovich, former Naiad chief engineer and for the last 
15 years or so head of Naiad Florida.  To quote my friend Scott 
Flanders, another Naiad fan, Vic is the real deal-he does what he 
says and he stands behind his company's products like nobody else. 
Vic is my Naiad oracle!

Bluewater's Naiad active fin stabilizer system is still under 
warranty, and I spoke with Vic today about the repair.  To a trained 
hydraulics guy, our Naiad system is a robust and simple system, and 
changing out a potentiometer ought to be a quick and easy task.  To a 
shade-tree mechanic like me, however, it's a different matter!   Do I 
have the skills to needed change the potentiometer and align it 
properly?  Perhaps with detailed instructions and help from 
crewmember George, whose mechanical skills leave mine in the slow 
lane, and  from Med Bound 2007 Chief Engineer Bernie Francis, whose 
principal technical skills are in diesel mechanics, I can pull it off.

Meanwhile, we're rolling along nicely.  To be sure, we're rolling 
more than we would with two working fins, but Bluewater's crew 
remains a contented one and our loss of a stabilizer fin is best 
considered an inconvenience rather than a serious problem.

--Milt, Judy, George and Schipperke Katy