Page 28 - CHIRP annual digest 2016.pdf

CHIRP Maritime

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

A report of a near miss at a busy crossing section of a TSS,
Article. 24 this includes an excellent response from the Third Party.
A Potential Close Quarters Situation in What did the reporter tell us?
the Approaches to the Cape Roca TSS Own vessel was proceeding in a lane of a Traffic Separation
What a reporter told us Scheme that was in close vicinity to a bank. A ferry was
A ship approaching a TSS, still at a distance of 12 nautical observed leaving Port A bound for Port B. Initially the
miles, is concerned by the actions of another vessel – on closest position of approach (CPA) was 1.5 mile astern of
the reporter’s port quarter, probably overtaking – who is me. At a range of about 4 miles he altered course 40
closing on a steady bearing. ‘The other ship’ alters to port degrees to starboard, resulting in a CPA and bow crossing

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