What a difference a day makes...
Rhiann Marie - Round the World
Stewart Graham
Tue 25 Oct 2011 11:03
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Tuesday 25th October 0939 UTC 1039
BST
Wind: 3 Knots Variable, COG 042 Deg True, SOG 8.2
Knots
34:14.496N 007:47.533W
Whew! What a day yesterday was. I could only really
file a basic blog because of the conditions.
They were however pretty much what was expected,
though that does not lessen one little bit the impact of barreling along in 40 +
knot winds at speeds sometimes exceeding 18 knots!
Yaaaaaaaaaaahooooooooooooooooo! Easy to say now but it was a case of
feeling very small and vulnerable yesterday in these force nine conditions
and just hanging on. So close to the end of our trip exacerbates the anxiety
that something may go wrong but that in turn sharpens the focus on ensuring that
nothing does.
I also tried my best to look after Trish who
broke her two month old vow not to do another passage with more than one number
in its' distance! The poor soul, what a way to go back to sea! I made her
scambled eggs on two slices of Stugeron for
breakfast and though she thinks it helped she had to remain awake to hold on as
she was getting thrown all over the place. One impact during her "superwoman
leaving a bed" repertoire, even ripping a lee cloth out! Anyway it was only for
thirty six hours.
Speeds were on average above ten knots as I
had heavily reefed down. I left very little mainsail up and the boom right out
and prevented. On the opposite wing, on Starboard I had the genoa on the pole
with about three reefs in it. This gave better balance, as with any
more mainsail Rhiann Marie in a combination of the strongest blasts which were
up to 45 knots, and big following seas could roll wildly. With more balance on
the genoa on the pole up front, we were like a bull with a ring through its
nose being dragged ever forward (with ass at constant distance
directly behind) on our halter, which was the very insistent
gale.
Now a wee bit of technical stuff just for the
sailors. Every sailor needs to know their boat and believe it or not even
after almost 40,000 miles I am still learning more about how to handle Rhiann
Marie in various conditions.
Exact circumstances and conditions you see are
almost alway slightly different. Wind, sea conditions, currents and tides,
traffic, crew, itenerary, day time/night time, condition of boat, sails and
rigging etc etc. The list is endless.
Most of yesterday winds which were forecast to
between twenty and thirty three knots were, as always to be expected with
GRIB's, between twenty five and forty five knots bulding through the night
Sunday / Monday, and a bit ahead of forecast.
The wind direction was well forecast and that is
what induced me to grab the rare at this time of year, following
winds, though strong, which would project us north like a freight train,
through the middle part of our passage.
However on this occasion it was the very last leg
of our travels. Maybe a delivery type trip, however now that our
circumnavigation is complete and the priority is to get boat and crew home
safely and as far as possible without incident. So discretion being the better
part of valour (allegedly) I reefed heavily and decided to, believe it or not,
sail more slowly and more conservatively and try to avoid breakage. But herin
lies the dilemma you see. By running with more canvas Rhiann Marie would travel
faster and that in turn would lessen the apparent wind that the boat felt. e.g.
Wind 40 knots Rhiann Marie travelling at 15 knots almost dead down wind so
apparent wind of say 25 knots. The motion too is less rolly when more pressed.
Less rolly, but in a very narrow "slot" downwind sailing at 165 degrees to the
wind. That means when you do eventually roll with a big tumbling wave crashing
down behind you, the leeward side of the mainsail is exposed to the wind and you
will broach to or crash gybe (possibly wake your wife up even) and be lucky
not to have very major damage. (See my blog Break, Break, Brake! on 14 August
2010 when we were lucky not to lose our boom or even our mast). In fact
describing this now I can hardly believe that that back en route to Fiji in a
moment (well a day actually) of irresponsible exuberance I sailed Rhiann
Marie with all canvas up and winds of 33 knots, what a bloomin'
..............................................
blast! Yeehaa!
Now however, older and wiser and sooooo close to
"home" I decided to reef down heavily so we have 40 knots of wind and boat speed
of average 10 knots.... We now feel apparent wind of 30 knots. Force being a
function of the square of the velocity that gives us 900 (30 x 30). Our example
above gives us 550 (25 x 25). That means the difference in having more
canvas up is (theoretically of course in non dynamic conditions) is only 61% of
having less canvas up. The motion also is less rolly and less waves pass under
the boat because of boat speed, meaning less surfing and less falling off the
back of waves with more canvas up and higher boat speeds. Note that on my Fiji
run we had high average speeds between 13 and 15 knots. Yesterdays experience
was an average of nearer 10 knots with speeds sometimes accelerating
to 13, 15 and even above 18 knots - but of course what all these sailors who
tell you about highest speeds forget to tell you is, that falling off the back
off these waves you have just surfed delivers speeds right down to 6 knots
hence the lower average.
Anyway to the critical point. Once you understand
all these things the trade off in terms of how much canvas to carry, is that of
risk. With less sail you will have higher apparent winds but of course it is
pressed against less canvas so loads on the boat may still be lighter. There is
also much less risk of you crash gybing or broaching to. It will however be
more rolly due to the waves passing under you and may to some extent be LESS
comfortable. With more canvas up you feel less apparent wind
though the boat's rig may be more heavily loaded you will
probably roll less and it may in fact be more comfortable. That is, unless you
roll into a broach or worse, crash gybe, in which case if the boat suddenly
stops your apparent wind will go (40knots - zero boat speed) to a formula
component of 1600! Then its most likely home-less quickly and mastless
quickly.
Yesterday had we another consideration which was
that if we sailed faster we would stay in the strongest of winds for much longer
and I had my wife to consider....... so like a lightweight we took it "easy" uncomfortably and rolly but
less risky ....... and just a little bit slower to let the gale overtake us.
We planned to and wanted to ride ii but not endlessly. Slower of course
is a relative term and of course we covered a lot of ground yesteday
well over two hundred miles. The conditions were spectacular though and it was
quite majestic to be sitting on a secure and well found boat in a sea of white
streaks and tumbling surf bursting from the grey power of the ocean and its
rippling muscles. A reminder that it was only just flexing them as a reminder to
us ..........
Just in case yo have any doubt about the conditions
here are a couple of snapshots of the instruments yesterday! Oh yes,
and one of your author who has laboured for many a long hour at the keyboard at
this station, though not always in such benign conditions as todays photo
shows!
Well our Gibraltar ETA is noon tomorrow. We must
not be complacent in the traffic. As for the wind however none other than a
light following wind is forecast - for now anyway.
Let me know your book thoughts on rhiann {DOT} marie {CHANGE TO AT} gaelforce {DOT} net
and thanks to those who already have.
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