It is one of the most tragic
maritime accidents in recent times. The 7-year old, 291 meters long cruise ship
Costa Concordia capsized outside Giglio Island harbor on the 13th of January
2012, killing 32 people.
The Costa Concordia was carrying
4,252 people from all over the world and was on the first leg of a cruise
around the Mediterranean Sea. She had left the Italian port of Civitavecchia in
Lazio, when she hit a reef during an unofficial near-shore salute to the local
islanders.
To perform this manoeuvre, Captain Francesco
Schettino had deviated from the ship’s computer-programmed route, claiming that
he was familiar with the local seabed.
It was 20:43:25 in the evening when
the Costa Concordia set course on a heading to Le Scole rocks. There was only a
distance of 2 ship’s length when the Costa Concordia’s bridge team saw the
razor-sharp Le Scole rocks right ahead, if not a little bit on her starboard
side. At this moment the Captain gave the order: “Hard to starboard”
The ship had a speed of 15.9 knots.
She had started to turn to her starboard side, but at the same time she was
drifting in a direction opposite to where she was being steered to: right onto
the Le Scole rocks. The time was 20:44:53 and the speed was 15.3 knots when the
Costa Concordia’s bow just missed the rocks but the ship was still drifting
towards the lethal Le Scole rocks.
And now comes the contentious
point.
Could the Costa Concordia have
missed the rocks, if the ship was put “hard to port” when the bow had just
missed the rocks?
Well, this is the most recent
argument of Captain Schettino, who has put the blame on the Indonesian helmsman
of the ship.
Schettino said: “From the black box,
you can hear that I had asked the helmsman to move the rudder to port and said
“port, 20 to the port!”. At that time the ship had an angle leaning towards the
starboard and the error of not putting it to the port immediately -, the delay
of this action has, caused this accident”
Well, on paper, Schettino is right!
In ship maneuvering terms, such a command would have resulted in the
starboard-side swing of the ship’s stern (away from the rocks).
Theoretically this could have saved the ship’s stern from hitting the rocks
hard. Of course this is if you can forget about the initial drift.
As a ship maneuvering expert, I
analyzed the ship’s AIS track many times, and also watched the animation made
by Transas which shows how the ship had drifted towards the rocks. From
the speed data, it is clear that the ship’s speed had dropped during the whole
process, which was good for reducing the impact of collision but bad for the
maneuverability of the ship. My final thought is that the collision with the
rocks was inevitable from the point when Captain Schettino took the wrong
decision at 20:43:25 to take the ship just 600 meters away from the rocks!
This reminded me of another tragic
disaster, when the Titanic hit an iceberg in the Atlantic, probably an iceberg
as sharp as the rocks of Giglio Island.
“Iceberg, right ahead!”
These three words were spoken by
Lookout Frederick Fleet at 11:40 p.m. on 14 April 1912 from the crow’s nest of
the ill-fated RMS Titanic. The story goes that, reacting to this three-word
warning, First Officer William Murdoch ordered “hard a-starboard.” The ship
started to turn to port, but its bow grazed the iceberg.
Looking at both incidents- Titanic
and Costa Concordia- I see that the situations were nearly the same, preventive
actions were nearly the same, and results, also were nearly the same! Both
ships were badly damaged from the side, that made the transvers bulkheads
useless and as a result, their sinking was inevitable.
(Attentive readers might have
noticed the above command and resultant reaction of the Titanic: Helmsman was
ordered hard to starboard and ship moved to port. The reason is that in the
British Merchant Navy steering orders used to be given as helm orders as though
the helmsman at the wheel was actually holding a tiller. So ‘hard a starboard’
would mean ‘put your helm or tiller hard a starboard’. This would turn the
ship’s rudder to port and so the ship would turn to port.)
In both situations, both with the
Titanic and the Costa Concordia , a preventive command could have stopped
the ship in the shortest time possible; which is:
“Stop! Full astern!”
On ships, this action is called as
“Crash stop” in which the engine is put to full-astern without any concern
about possible damage to the main engine A modern cruise ship with strong
engines can stop within 3 ship’s length at 24 knots speed when put to full astern.
In the case of Costa Concordia which was at 15,9 knots and at a distance of
more than 2 ship’s length to the rocks ahead- the time when Schettino had
ordered “hard to starboard”; nothing but a “crash stop” could have saved
the ship and lives of 32 passengers, including the Captain’s own
professional life.
During a crash-stop manoeuvre, the
ship’s heading can be maintained by the bow thrusters in order to avoid damage
to the sides. A head-on crash onto the rocks at low speed-in case the ship
could not have stopped before- would result in insignificant damage to the ship
and the bulkhead doors would have perfectly prevented the ingress of water... ν
Source : SN-TR.
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