The Case Of The Fall From
Grace
ZMF 2014
m/v Lowlands Grace
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Lowlands Grace is a Hong Kong registered cape-sized bulk
carrier of 149 518 deadweight tonnes at its summer draught
of 17.325 m
We’ll call them Paul and Butch. Not their real names but they were
real people. They can no longer tell you their story.
Paul was Third Engineer and Butch was an Ordinary Seaman aboard
the Lowlands Grace when she anchored in ballast nearly 12 miles off
Port Hedland, Australia on the morning of the 6
th
of October, 2004 to
wait for a cargo of iron ore for China.
The Lowlands Grace was a fairly standard bulk carrier of about
150,000 deadweight tonnes. She was registered in Hong Kong and
had a crew of 25.
Most important for our story she carried two totally enclosed
lifeboats on gravity davits, each capable of carrying a complement of
32. The starboard lifeboat was the designated rescue boat. The
lifeboats were built by the Blue Sea Industrial Company of Taiwan,
which was no longer in business. They’d been designed by a
respected British company, naval architects Laurent Giles, founded in
1927.
The on-load release hooks were made by William Mills Marine, now
part of the ubiquitous Schat-Harding Group. William Mills Marine has
quite a history. It built Britain’s first aluminium foundry, produced the
first aluminium golf club head and its founder William Mills invented
the Mills Bomb hand grenade that was in service with British forces
from 1915 to the 1960s.
There was little special about the lifeboats aboard the Lowlands
Grace. They were 7.3 metres long with an unladen weight of a little
more than three and a quarter tonnes, rising to somewhat more than
5 and a half tonnes when full. There was a raised coxswain’s position
with the boat’s controls within easy reach.
One of the lifeboat suspension rings
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Behind the aft bulkhead
One of the lifeboat suspension rings
Manufacturer’s
suspension rings
Behind a plywood bulkhead was the forward keel stay and
attachment for the forward lifting hook. A similar arrangement was
behind the aft bulkhead, together with parts of the tiller and engine
exhaust. Both bulkheads had inspection hatches.
Each lifeboat was suspended from its falls by an elongated ring.
It wasn’t what the manufacturer specified, they should have been
circular rings, but perhaps nobody thought the difference was
important.
The lifeboats were not supported on chocks in the stowed position so
the keel stays took their entire weight.
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Schematic showing after
hook keel attachment
the hook and lifeboat suspension ring
The lifeboats were not supported on chocks in the stowed position so
the keel stays took their entire weight.
Lowlands Grace couldn’t berth for another couple of days so there
wasn’t much to do except for the usual daily shipboard routine. The
next day, the 7th, the weather forecast was good and the master
decided to hold a lifeboat drill.
A little before 1500 hours, the time scheduled for the drill, the master
relieved the second mate on anchor watch so he could take part in the
drill.
Paul, Butch and the rest of the lifeboat crew assembled at 1500 at the
port lifeboat muster station. Over the next 20 minutes the first mate
briefed the crew on safety procedures and emergency duties.
At 1520, the crew cleared the gripes of the port lifeboat and lowered it
to the embarkation position at boat deck level.
The ship’s chief mate gave the third mate command of the lifeboat with
Paul, Butch, the fitter and an able seaman as crew.
Each man entered the lifeboat wearing a hardhat and lifejacket and
belted themselves into their seats.
The boarding hatch was closed and the third mate called the chief mate
on his handheld radio to say that they were ready to lower the boat. The
chief mate told him to lower away and he operated the remote davit
brake release cable.
The boat lowered under its own weight for around two to three metres.
Then the third mate tested the davit brake by releasing the cable.
It stopped with a jerk. Then there was a bang and the men in the
lifeboat heard the sound of tearing fibreglass as the stern dropped. Men
on board the Lowlands Grace watched horrified as the lifeboat swung
around the foreward hook. The afterhook assembly ripped through its
hull and dropped into the water below.
The lifeboat continued to rotate around the forward suspension to about
220 degrees, then the forward hook opened and the lifeboat fell, upside
down, 16 metres, nearly 50 feet, into the water below.
The lifeboat was still secured to the ship by a painter so the Chief Mate
and the Boatswain lowered the gangway. As they did so the third mate
escaped and climbed on top of the upturned hull. Then came Paul and
an able seaman, then the fitter.
With the gangway lowered, crew were able to help Paul and the fitter
onto the inverted boat. Butch was still inside so another AB swam into
the lifeboat to find him. He surfaced a short time later to say that he
thought Butch had drowned.
By now, Paul was having difficulty breathing.
As they waited for medical assistance from a nearby warship, the HMAS
Melbourne, Paul lost consciousness so some of the other crew started
CPR.
When Australian navy divers entered the lifeboat they found Butch in his
lifejacket floating face down. The divers cut off his lifejacket and
extracted him from the boat.
By now, Paul showed no sign of life. Aboard HMAS Melbourne a doctor
pronounced Paul and Butch dead.
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The afterhook assembly ripped through
its hull and dropped into the water
The snapped port lifeboat keel stay
The story of what happened to Paul and Butch actually began a long
time before October 7, 2004. Over time, sea water got into the lifeboats
and, because ships tend to be trimmed by the stern, settled behind the
lifeboat after bulkhead. By the time of the incident, as much as 25 per
cent of the keel stay had been eaten away.
With the lifeboats supported only by the falls, the keel stays took the
shocks of the ship’s movement and occasional rough handling during
drills. Perhaps a small crack appeared, and grew with each jolt and
bump, until the final shock load on October 7 when the third mate
applied the davit brake.
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The lifeboat is recovered
aboard a barge
extensive damage from the fall
lists specific checks for on-load release systems,
which includes the condition of the hook fastening, implicitly, the keel
stays.
Why wasn’t the corrosion spotted? The ship’s SMS procedures only
included two items related to the on-load release system: that the
quick release system and lifting hook be greased and the cables and
control handles be checked for excessive play, and that the lifeboat
should be lowered and auto released and maneuvered in the water for
15 minutes every three months. Nothing about checking the keel stays.
But the SMS did carry the advice that routine maintenance should be
carried out as defined in the manufacturer’s manual.
The manufacturer’s manual didn’t expressly mention keel stays, but it
does say that there should be a weekly check for corrosion that may
need corrective action and a monthly check that should also look for
signs of corrosion and dirt among other things.
The maintenance instructions did include checking the cables and
clamps which are located on the keel stays. If those instruction were
being followed, it’s hard to see how the poor condition of the
attachments could have gone unnoticed.
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Lifeboat forward and after hook
suspension rings after the accident
Forward suspension ring on hook
Even with the failure of the after hook, the lifeboat should still have
been held by the forward hook. Hooks should be designed with a
safety factor of six. For the lifeboat on the Lowland’s Grace, that’s 30
tonnes. On the day of the accident the lifeboat had a total weight of
3.65 tonnes, about 12 per cent of the designed strength.
In fact, The load of the hook may have reached as much as 50 tonnes
instantaneous load without failing, but the lifeboat was suspended by
an elongated ring which contacted the hooks pivot pin and multiplied
the opening force.
The ATSB also identified the release hook itself as prone to open when
not fully reset or when parts of the mechanism is worn. It’s a type
that has been implicated in several lifeboat accidents yet is still in
use.
Staying alive in a lifeboat may well depend on your maintenance so
go and check those keel fixtures now. While you’re at it, make sure
the lifeboat suspension rings follow the manufacturer’s specifications.
And, of course, that the hooks are properly set.
Try to remember :
IF YOU DON’T CARE OF YOUR
LIFEBOAT , IT WILL NOT TAKE
CARE OF YOU !!!
Lowlands Grace’s Events and causal factor
chart
CONCLUSIONS
The port lifeboat’s after hook’s keel stays were wasted
(corroded), around the point of attachment to the keel block,
to the point where they had little remaining strength.
While the lifeboat was being lowered a momentary shock
load, when the third mate halted the lowering, caused the
after hook’s wasted keel stays to fail and separate from the
keel block. The stern of the lifeboat then dropped, with the
boat swinging forward and rotating about the fixed point of
the forward fall.
When the lifeboat was vertical, or close to it, the foredeck
failed, and in the process the end of the operating cable for
the forward hook was damaged (bent) which led to the
hook’s cam release pin being rotated some way towards its
tripping position.
CONCLUSIONS
The lifeboat rotated to approximately 220 degrees with the
forward hook being subjected to very high opening forces
which rotated the cam release pin until the hook opened.
The lifeboat, now detached from both falls, then fell
approximately 16 m to the water, still inverted, to strike
slightly bow down.
The corrosion and wastage of the port lifeboat’s after hook’s
keel stays occurred over a relatively long period of time due
to its conditions of service.
The ship’s planned maintenance procedures with respect to
the on-load release systems fitted to the lifeboats were
deficient as the condition of the wasted keel stays had not
been detected and rectified.
CONCLUSIONS
The lifeboat’s survey regime was deficient with respect to the
on-load release systems fitted to the lifeboats as the
condition of the wasted keel stays had not been detected and
rectified.
The suspension rings fitted to the lifeboat davit falls were
incorrectly sized and subjected the forward hook to greatly
increased opening forces while the lifeboat was swinging.
The design of the on-load release system is also implicated in
the failure of the forward hook as the system of locking the
hook became particularly prone to spontaneous release when
the operating cable was damaged.
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