The following commentary is based largely
on the preliminary ATSB report and like it
is subject to change.
The preliminary ATSB report makes it pretty clear
that the primary cause of this grounding was fatigue.
The Chief Mate, who was the officer of the watch,
had had 2.5 hours of broken sleep in the last 37 hours,
when he took over the watch at 1600 hours.
Depsite 20 years at sea, 11 as mate, and 3 as chief mate,
he made a number of elementary mistakes,
including failing to plot the ship's position
for nearly an hour after taking over the watch
and failing to switch charts at the right time.
As a result he failed to make the required
starboard turn from 020 to 075 on time
despite the channel being 12 miles wide.
The reason for the lack of sleep was the crew size.
The 70,000 ton ship had a crew of 23,
about average by current standards,
but far below pre-1980 standards.
The ship had four deck officers
including the Master, the Chief Mate (C/M), and two other mates.
The three mates serve as officers of the Watch
on a 4 hours on/8 hours off schedule.
But the C/M is also responsible for loading and discharging the cargo.
In this case, the loading process including berthing
lasted from 0300 on 2010-04-02 until 1115 on 2010-04-03,
about 32 hours.
(Often it is longer.)
During this time, the C/M had at most 2 hours sleep.
After departure, he had had another half-hour's sleep,
when his alarm rang at 1530 to get ready
to start his watch at 1600.
There is simply no way a human can function
at anywhere near 100% with 2.5 hours sleep in 37 hours.
On some ships, it is the practice for the Master,
who is normally much better rested,
to take the C/M's first watch after departure.
But this is up to the Captain
and often the Captain declines,
sometimes citing paperwork requirements
which have increase enormously in the last two decades,
while at the same time, the Radio officer,
which usually served as a sort of ship's secretary
In any event, the rule should be clear.
No one can serve as OOW unless they
have had at least x hours sleep in the y
hours before their watch starts.
If that means, a 5th deck officer, so be it.
The ship was equipped with GPS
but apparently not ECDIS.
The 2/M had altered the planned course
and waypoints slightly in the preceeding watch.
The C/M was informed of this.
But the 2/M failed to alter the off-course alarm.
Instead when the GPS alarmed on the new course,
he accepted the alarm,
efffectively disabling the alarm.
If the alarm had been re-set,
it might have woken the C/M up
in time to make the turn.
The 2/M was also probably tired.
On a 3 mate ship,
during load discharge, it is normal practice
for the two junior mates to work 6 on /6 off.
But the six off is often illusory
as the mates have to do voyage planning,
order/check stores, etc during the off periods.
The fully loaded ship went aground at about 12 knots.
The ship had a draft of 13.3 m fwd and 13.4 aft.
Some claim a 2 mile gash in the coral.
This ship has a double bottom
and the double bottom tanks are arranged
in a 3x5 pattern.
Some of the double bottom tanks are ballast
and some are bunkers.
Several double bottom tanks
including one bunker tank were holed
as well as the engine room,
indicating the damage extended
close to the full length of the ship.
The seven cargo holds were not breached.
(At his point CTX has no real details of the damage).
The area where Shen Neng I ran aground
had a charted depth of about 10.8 m.
Very fortunately, she ran aground
at almost exactly low tide (1706),
at which point the water depth was 0.8 m above datum.
So the water depth at impact was about 11.6 m.
(The ship measured 11 m on port side and 12 m on starboard.)
The flooding tide improved the hydrostatic balance,
and apparently less than 5 tons of bunkers was spilled.
The following high water (2.8 m above datum)
was at 0002 the next day,
enough time to transfer fuel from the holed tank.
Ship switched from ABS to China Classification Society in 2007.
But she had a pretty good port state record:
four deficiencies since 1998, and no detentions.
Had traded to US and Europe in 2005.