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tacking
"Board
the Tack!"
Two
kinds of maneuvers are quite common on the MIR: the tacking and the
wearing the ship.
Both are complicated affairs on a big square rigger and need solid
preparation
and a well trained crew - especially when tacking the ship. Let us look
at the maneuver
with the eyes of the commanding officer from the bridge. For
that purpose I describe a routine tack in the way it takes place when
the
ship is zigzagging against the wind. Normally those maneuvers do not
come out of
the blue, but are announced in advance. Captain and watch officer have
agreed about
how long to stay with one course - e.g. until the ship reaches a
certain
position, a landmark comes in sight or until a certain time like a
changing of
watches when most of the crew are on deck anyway. Normally an
announcement is
made to inform the crew about the approximate starting time of the
maneuver: "Tonight at 8 we will board a tack with all hands!" For this
text I assume that the tack is planned by geographical means (e.g.
crossing the
0-meridian). In this case the watch officer regularly checks the
position and
when the ship comes closer to the turning point a chain of events
happens.
Immediately before the entire maneuver begins he will call the captain
-
unless he is not already on the bridge - to hand over the command to
him.
1.
PREPARATIONS
Before
the deck's crew or the free watch even notices that a maneuver is about
to start,
there are some preparations to be done on the bridge.
The
engine control room gets informed to pump the ballast water to the
other
side.
The
galley gets informed to give them a chance to secure the pots and pans
and
other materials.
The
bosuns get called to the bridge to get informed about the way the
maneuver is held today in accordance to the weather or other special
problems that might
influence his work.
The
position of the ship is checked permanently now and is also controlled
manually. On the radar and the GPS the positions and courses of the
other in
this area operating ships get checked and a peering is made
towards other
objects and ships in sight.
Eventually
other traffic gets informed by radio that a change of course will take
place. This might change the right of way for the other ships and it
might be
important for them to know that the sailing vessel ahead might become
very slow
and then suddenly very fast again after the tack. This is especially
important
for the ships behind us that are faster than MIR. Unfortunately
nowadays one
cannot assume the watch officers on cargo ships to know what will
happen when a
sailing ship turns. Good information is a matter of OUR safety...
If we
are near to the shore or in an area of heavy traffic (German Bight,
Straight of Dover,...) it might be necessary to inform land based
stations as
well.
Now the
sailing alarm is given. It is also announced what kind of maneuver will
follow. A tack is almost always made with "all hands", for wearing the
ship it is sufficient to have two watches on the deck, e.g. during a
change of
watches. In this case the free watch will not be disturbed in their
sleep.
After
the announcement "vsje navjerkh gatovy" everybody on board
appears on the deck in weatherproof working gear and if belonging to
those who
lay aloft also with the safety harnesses already put on. Everybody
reports to
his station. Exceptions can be the engine staff who is on watch in the
engine control
room, the cooks if they have the pots on the fire and the bridge staff.
Helmsman and lookout stay on their position until they get released by
those who
will do these jobs during the maneuver.
All
lines needed for the maneuver get thrown off.
2.
THE TACK
As
a rule on the MIR a change of direction will be done through tacking
the ship.
There is a big crew and MIR is a very handy ship that follows rudder
and helm even
in strong breezes without problems. During a tack the ship goes through
the wind
with the bow first "overshtag". With a well trained crew the entire
maneuver
will take about 20 minutes. Every master has got his own way to sail
the tack
although it is mainly all the same. In the following the tack
is described
in the way Captain Antonov sails it.
The tack
is started
from a position very high on the wind (30°)
At first
the rudder is laid hard windward (35° rudder
position) and at the same time the spanker driven completely to
windward.
By the
time when the sails start flapping, the courses and eventually also the
royals get clewed up. Now the
yards of the mizzen mast are braced around and the sheets of the
staysails are
eased.
When the
bow goes through the wind, the sheets of the stay sails are thrown off
so that they all can fly to the other
side on their own.
When the
bow has cut through the wind the helm is laid back into midships
position. The
ship keeps on turning through the fore sails staying aback in pressure
of the wind. Only in case of a complete
stop of turning it might be necessary to steer
slightly to the other side.
Now the
ship is already on the new tack - has an angle to the wind of approx.
15-20°. The staysails are fastened to the wind again starting
from the stern to
the bow.
The
yards of the fore topp are
braced together with the turning of the ship so that the sails are all
the time
flapping but never completely aback. The main topp can be braced either
together with the fore topp or
with the mizzen or at any time in-between.
At last the
fore sails are taken to the other side they are left aback until the
ship has
completely gone to the by-the-wind-position on the new tack.
Then
the courses and eventually the royals get
set again.
The
sails get
trimmed into the new position by the wind.
The
helmsman finds the new zero position of the rudder and steers the new
course according to the orders of the captain or commanding officer.
3.
WEARING THE
SHIP
Certain
weather conditions (minor winds or storms), a reduced number of crew
members in
the early season when there are no cadets on board, or night maneuvers
when -
as the ship is not in a race - the captain does not want to wake the
free watch, or an
untrained crew can lead to the decision to wear the ship instead
of tacking. This maneuver is easier to do, but needs more time and the
ship
looses some miles in the needed direction as it is forced to describe a
circle.
The main difference is that when wearing it is not the bow that goes
through the
wind but the stern. We turn "fordewind".
It
begins with clewing up the courses.
Then the
rudder is laid to the leeward side.
The
spanker is clewed up and the mizzen gets braced around to be taken out
of
the wind. So the wind hits only the sails on the fore half of the ship.
With
these unequal forces the ship turns quickly and the mizzen stays aback.
During
this turning the main and the fore topp get braced lively, what means
their sails remain filled.
The fore
topp remains in an square position. At the moment when the mizzen is in
the wind again, the main topp gets braced around.
Staysails
and fore sails get hold tight to the wind.
The fore
topp gets braced around.
The
courses and the spanker are set again.
The ship
is steered towards the wind.
The
helmsman finds the new zero position of the rudder and steers the new
course
according to the orders of the captain or commanding officer.
4.
AFTER THE MANEUVER
When
the ship is already on the new course there remains some work to be
done before the free watch gets released again.
The deck
must be cleared up again. That means that all lines have got to be
belayed
again and everything has to be returned to it's normal position.
Everything must
be prepared ready to start a new maneuver immediately.
The
cadets will hear the "maneuver critics" to learn what they can do
better next time.
The free
watch gets released. "Adboy!"
The
watch returns to their duties.
Cadets
(or trainees) take over helm and lookout again.
The
position gets checked again.
The new
course gets announced and noted onto the sea chart.
The
maneuver and possible special entries are noted into the ship's journal
(logbook).
The
surrounding traffic gets informed that the maneuver is finished now.
The
engine control room is told to check the trimming ballast again.
The
bosun appears on the bridge and reports about the maneuver, the cadets
and
other things.
The
captain hands over the command to the watch officer.
