CHIRP annual digest 2016 6th

CHIRP Maritime
The lessons to be learnt
We do not in this case have the identity of or comment
from the third party (ship 2); so the exact circumstances
onboard are a matter of conjecture. The most probable
explanation of this event is a loss of concentration on
the bridge. It is also possible, but there is no evidence,
that a technical failure may have contributed: of auto -
matic steering, or the steering gear itself for example.
A highly dangerous situation arose; had ship 2 pro -
gressed any further before her alteration back to
starboard into the south west lane, she would have
been at very close quarters with ship 3, and quite
possibly in collision. We see again how quickly such a
situation can develop, especially in dense shipping and
constrained waters. The danger is further exacerbated
when the constriction of a TSS brings – in this case three
large vessels into close proximity with almost no sea
room to spare: the “sandwich effect”.
CHIRP Suggests
Traffic separation Collision Regulations (COLREGS). Ship
2 certainly contravened COLREG 10(b)ii (“… keep clear
separation line”) by encroaching on the separation line,
and at least came close to contravening COLREG 10(b)I
(“… general direction of traffic”).
Other COLREGS. She also failed to take ‘positive action in
ample time’, and was probably failing to keep a proper
lookout. These failures may well have been exacerbated
by overload, tiredness, distraction, undermanning, and/or
failure to look up and out. Obviating these risks must be
part of the passage planning process and supervision at
the time.
Overtaking in a highly constrained part of a TSS or
approaching a corner can be dangerous and reduces
options. In this case the reporter’s ship had no room to
starboard as she approached the Bergues North buoy.
Look and think ahead.
The above article was published in MFB 43
Article. 24
A Potential Close Quarters Situation in
the Approaches to the Cape Roca TSS
What a reporter told us
A ship approaching a TSS, still at a distance of 12 nautical
miles, is concerned by the actions of another vessel – on
the reporter’s port quarter, probably overtaking – who is
closing on a steady bearing. ‘The other ship’ alters to port
at just under a mile, giving a CPA of 3 cables. The reporter
who is himself overtaking another vessel on his starboard
side with a speed advantage of 0.4 knots, slows down, and
alters to starboard to open the CPA on ‘the other ship’,
presumably under the stern of the one he was very slowly
overtaking
Lessons to be learnt
The report highlights the kind of relatively close
quarters situations which may arise as ships shape
courses for the entrances to TSSs. This process requires
action in plenty of time, and a well considered assess -
ment of other ships’ intentions based on a good
all-round lookout, so that – where other ships are
present – an orderly separation of ships is already
established before the scheme itself is entered.
The complication arises from what amounts to two
simultaneous overtaking manoeuvres. The reporter is
constrained to starboard, and will be for a long time as
he gains less than half a mile per hour on the vessel on
his starboard side. He could perhaps have minimised his
constraints by instead ‘slotting in’ astern. ‘The other
ship’ might have alleviated the reporter’s concern by
allowing more sea room, and could also have de -
celerated; we do not know how or if he was constrained
to port.
CHIRP Suggests
Plan well ahead and keep a complete all round lookout
when taking up position in an approach to a TSS; take
account of the manoeuvring options of other ships. If
overtaking, do it as quickly as possible. If sea room is at a
premium, slow down and don’t overtake. See ‘The Perils
in TSSs’ (Maritime Feedback 42).
The above article was published in MFB44
Article. 25
Close Encounter Crossing a Traffic
Separation Scheme (TSS)
A report of a near miss at a busy crossing section of a TSS,
this includes an excellent response from the Third Party.
What did the reporter tell us?
Own vessel was proceeding in a lane of a Traffic Separation
Scheme that was in close vicinity to a bank. A ferry was
observed leaving Port A bound for Port B. Initially the
closest position of approach (CPA) was 1.5 mile astern of
me. At a range of about 4 miles he altered course 40
degrees to starboard, resulting in a CPA and bow crossing
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