Ingangsdatum: 01-11-1993
4.2.1 Scope
The provisions
given hereunder apply to decked seagoing fishing vessels as defined in
1.3.4. The stability criteria given in 4.2.3 and 4.2.4 below should be
complied with for all conditions of loading as specified in 4.2.5,
unless the Administration is satisfied that operating experience
justifies departures therefrom.
4.2.2 General precautions against capsizing
Apart from general precautions referred to in sections
2.3 and 2.5, the following measures should be considered as preliminary
guidance on matters influencing safety as related to stability.
.1 all fishing gear and other large weights
should be properly stowed and placed as low as possible;
.2 particular care should be taken when pull
from fishing gear might have a bad effect on stability, e.g., when nets
are hauled by power-block or the trawl catches obstructions on the
sea-bed;
.3 gear for releasing deck load in
fishing vessels carrying catch on deck, e.g., herring, should be kept in
good working condition for use when necessary;
.4
when the main deck is prepared for the carriage of deck load by
division with pound boards, there should be slots between them of
suitable size to allow easy flow of water to freeing ports to prevent
trapping of water;
.5 fish should never be
carried in bulk without first being sure that the portable divisions in
the holds are properly installed;
.6 reliance
on automatic steering may be dangerous as this prevents changes to
course which may be needed in bad weather;
.7
in all conditions of loading necessary care should be taken to
maintain a seaworthy freeboard.
.8 particular
care should be taken when the pull from fishing gear results in
dangerous heel angles. This may occur when fishing gear fastens onto an
underwater obstacle or when handling fishing gear, particularly on purse
seiners, or when one of the trawl wires tears off. The heel angles
caused by the fishing gear in these situations may be eliminated by
employing devices which can relieve or remove excessive forces applied
through the fishing gear. Such devices should not impose a danger to the
vessel through operating in circumstances other than those for which
they were intended.
4.2.3¹
Recommended general criteria ²
4.2.3.1 The general intact stability criteria given in
section 3.1.2 (paragraphs 3.1.2.1 to 3.1.2.3) should apply to fishing
vessels having a length of 24 m and over, with the exception of
requirements on the initial metacentric height GM
o (paragraph
3.1.2.4) which, for fishing vessels, should not be less than 0.35 m for
single deck vessels. In vessels with complete superstructure or vessels
of 70 m in length and over the metacentric height may be reduced to the
satisfaction of the Administration but in no case should be less than
0.15 m.
4.2.3.2 The adoption
by individual countries of simplified criteria which apply such basic
stability values to their own types and classes of vessels is recognized
as a practical and valuable method of economically judging the
stability.
4.2.3.3 Where
arrangements other than bilge keels are provided to limit the angle of
roll, the Administration should be satisfied that the stability criteria
referred to in 4.2.3.1 are maintained in all operating conditions.
4.2.4 Severe wind and rolling
criterion (weather criterion) for fishing vessels
4.2.4.1 The Administration may apply the
provisions of 3.2 to fishing vessels of 45 m length and over.
4.2.4.2 For fishing vessels
in the length range between 24 m and 45 m, the Administration may apply
the provisions of 3.2.
Alternatively the values of
wind pressure (see 3.2.2.2) may be taken from the following table:
| h (metres) | 1 | 2 | 3 | 4 | 5 | 6 and over |
| P (N/m²) | 316 | 386 | 429 | 460 | 485 | 504 |
where h is the vertical
distance from the center of the projected vertical area of the vessel
above the waterline, to the waterline.
4.2.5² Loading conditions to be considered³
4.2.5.1 The standard loading
conditions referred to in 4.2.1 are as follows:
.1
departure conditions for the fishing grounds with full fuel, stores,
ice, fishing gear, etc;
.2 departure from the
fishing grounds with full catch and a percentage of stores, fuel, etc.,
as agreed by the Administration;
.3 arrival at
home port with 10% stores, fuel, etc., remaining and full catch;
.4 arrival at home port with 10% stores, fuel,
etc., and a minimum catch, which should normally be 20% of full catch
but may be up 40% provided the Administration is satisfied that
operating patterns justify such a value.
4.2.5.2 Assumptions for calculating loading
conditions should be as follows:
.1 allowance
should be made for the weight of the wet fishing nets and tackle, etc.,
on deck;
.2 allowance for icing, where this is
anticipated to occur should be made in accordance with the provisions of
section 5.3;
.3 in all cases the cargo should
be assumed to be homogenous unless this is inconsistent with practice;
.4 in conditions referred to in 4.2.5.1.2
and 4.2.5.1.3 deck cargo should be included if such a practice is
anticipated;
.5 water ballast should normally
only be included if carried in tanks which are specially provided for
this purpose.
4.2.6
Recommendation for an interim simplified stability criterion for
decked fishing vessels under 30 m in length
4.2.6.1 For decked vessels with a length less
than 30 m, the following approximate formula for the minimum metacentric
height GM
min (in metres) for all operating conditions should
be used as the criterion:
GM
min = 0.53+2B [0.075 - 0.37
(f/B)+ 0.82 (f/B)
2 - 0.014 (B/D) - 0.032(l
s/L)]
where:
L is
the length of the vessel on the waterline in maximum load condition (in
metres)
l
s is the actual length of enclosed
superstructure extending from side to side of the vessel (in metres)
B is the extreme breadth of the vessel on the
waterline in maximum load condition (in metres)
D is
the depth of the vessel measured vertically amidships from the base line
to the top of the upper deck at side (in metres)
f is
the smallest freeboard measured vertically from the top of the upper
deck at side to the actual waterline (in metres)
The
formula is applicable for vessels having:
- f/B between 0.02 and
0.20;
- ls/L smaller than 0.60;
- B/D between 1.75 and 2.15;
- sheer fore and aft at least equal to or exceeding the
standard sheer prescribed in regulation 38(8) of the
International Convention on Load Lines, 1966;
- height of
superstructure included in the calculation not less than 1.8 m.
For ships with parameters outside of the above limits the
formula should be applied with special care.
4.2.6.2 The above formula is not intended as a
replacement for the basic criteria given in 4.2.3 and 4.2.4 but is to be
used only if circumstances are such that cross curves of stability, KM
curve and subsequent GZ curves are not and cannot be made available for
judging a particular vessel's stability.
4.2.6.3 The calculated value of
GM
min should be compared with actual GM values of the
vessel in all loading conditions. If a rolling test (see section 7.6),
an inclining experiment based on estimated displacement or another
approximate method of determining the actual GM is used, a safety margin
should be added to the calculated GM
min
¹ Refer to regulation 44 of the 1966 LL Convention and the 1988 LL
Protocol.
² Refer to regulation III/2 of the 1993
Torremolinos Protocol.
³ Refer to regulation III/7
of the 1993 Torremolinos Protocol.
Note:
In paragraph 4.2.3.1, in
the second sentence, the word "it" was inserted after the word
"should" with the adoption of res. MSC.75(69) 14 May 1998. In
addition 4.2.4.1 and 4.2.4.1 were amended.
This
resolution was adopted on 4 November 1993.