Water Ballast Safety
My website at http://h260.com
draws a lot of traffic and I get very interesting questions and
suggestions for improvements. I've never tried to act as the
expert on the H26/260 (I'll leave that to Crazy Dave) -- I see my
role as facilitating the exchange of information between
potential, former, and current owners of these boats. I've learned
a lot from you all and I intend to continue the dialogue as long
as I can.
There is a lot of misunderstanding about how water ballast works,
and I've tried to address its various aspects in related pages. I
recently received a question regarding off-loading water ballast
in order to achieve more speed. It took me a while to sort out the
various issues involved. Here's the question and my response. I
welcome additions and any corrections from those more expert in
this area than I.
QUESTION:
"Hello! Great article—lots of info! I’m racing in a keel
boat regatta this weekend and was looking for a legal edge—do
think it would be okay to sail with about half (or less) water
ballast on board? I’d like to go faster, but I don’t want to
sink my boat doing it! Expected conditions are steady winds 9-12
knots."
ANSWER:
" I'll assume this is not a trick question and you really
consider doing this.
Hunter warns that it's unsafe to sail or motor the H26/260 with
less than a full ballast tank. I know there have been people that
have tried unloading their ballast tanks for various reasons, but
the hassle to me does not seem worth the effort and it might be
dangerous. Most ballast valves leak anyway, which makes keeping
less than a full load in the tank problematic. A couple of times
I've forgotten to open the ballast valve before setting out for a
sail. When I did check it, I found the tank full - apparently, the
seal is pretty weak and there is a lot of pressure on the valve
and the tank just wants to fill regardless of the operators error.
What you propose is like cutting off half or more
from a conventional lead keel thus modifying the US Coast Guard
approved design of the vessel. Once you modify the design of a
boat without consulting with a naval architect and getting
approval from the USCG, you could end up with an unsafe vessel and
open yourself up to all kinds of grief. The design of all
production boats is carefully calculated to provide safe sailing
within design parameters. Messing with the ballast in a boat is a
tricky proposition. Every now and then you read about a boat whose
ballast fell off and the boat immediately turtled; it happens so
quick, loss of life is a frequent result.
Finally, one of the first things a new H26/260
owner learns is the power in the H26/260 comes from the large
roach in the main and it does not take much to become overpowered
when the winds approach 10-15mph. I'm one of those "reef
early and often" guys. I can't even imagine how the boat
would handle with half or more of it's ballast missing in 9-12mph
winds. Looks like a disaster waiting to happen to me. One of
the things I like about the boat is how fast it sails and how well
it handles with a reef in the main.
Some other questions and problems come to mind:
I assume you'll tell the race committee and your competitors that
you have modified the design parameters of your boat - to not do
so is dishonest and would provide you an unfair advantage. You'd
probably be disqualified if this information was not made
available to the committee anyway.
I assume your regatta will use the US PHRF handicap system. As you
know, the PHRF system is designed to provide a level playing field
for dissimilar boats. The race committee will assign you a
handicap which normally ranges from 207 to 234 for a fully
ballasted H26. However, the committee will want to adjust your
handicap even further to compensate for the lighter load so I'm
not sure what advantage you'll achieve. Also, once the committee
finds out you are sailing a potentially unsafe boat, they may not
allow you to compete.
I assume you are not a naval architect. How do you intend to
calculate the weight of the water in your tank, keep it at a
constant level throughout the race, and how do you propose to
compute and compensate for the changes in weight and balance and
righting moment you'll experience so that you don't end up being a
customer of the US Coast Guard?
Another thought - As far as I know the ballast tank does not have
baffles nor are they needed. Since the tank is normally full, the
water does not "slosh" around. Let's assume you were
able to empty the tank to 50% and keep it there. It seems to me
each time you tack, you'll have 1000 lbs of ballast or about 25 %
of the total vessel weight shifting from one side of the boat to
the other. As a result the weight will be on the wrong side of the
boat to counter the heeling force of the wind, and when you tack
there will be huge weight shift in the boat. With the wind pushing
the boat to leeward, and only half of the ballast working to
resist the pressure on the sails, what do you think the result
will be?
Do you intend to advise your insurance company of
your intentions? I guess not, but if there were an incident, my
assumption is your insurance would be null and void and any claims
against you by crew and other boats would surely be upheld in
court. It's likely a first year law student could win this case.
Backyard mechanics run the same risk when they modify their car
suspension or set-up without consulting with an automotive
engineer (and an attorney).
Assuming
all the other issues could be addressed satisfactorily, would lightening
the boat really result in more speed? Of course, it would depend
on how heavily the boat was loaded in the first place. With a
planing hull there is generally a direct relationship between
horsepower and speed. With displacement hulls, it's very
difficult to get the boat to exceed its theoretical hull
speed. You eventually reach a point of diminishing
returns - the more horses you apply, the more water
resistance you get.
If that is not enough to persuade you to reconsider this idea, why
not take a look at a very famous case where a boat without a full
ballast tank capsized resulting in the deaths of two children and
the operator went to prison for a long time. Alcohol was involved
in this case, but the primary cause of the accident was operation
of the vessel outside it's design parameters. For more on this
incident go to this link: http://www.ne-ts.com/ar/ar-407capsize.html
.