Resolution MSC.137(76)
STANDARDS FOR SHIP MANOEUVRABILITY
(adopted
on 5 December 2002)
THE
MARITIME SAFETY COMMITTEE,
RECALLING Article 28(b) of the Convention on the International
Maritime Organization concerning the functions of the Committee,
RECALLING ALSO that by resolution A.751(18), the Assembly approved
Interim Standards for Ship Manoeuvrability, whereby Governments were
recommended to encourage those responsible for the design, construction, repair
and operation of ships to apply the Standards and invited to collect data
obtained by the application of the aforementioned Standards and report them to
the Organization,
RECALLING FURTHER that by MSC/Circ.644, the Committee approved
Explanatory Notes to the Interim Standards for Ship Manoeuvrability to provide
Administrations with specific guidance so that adequate data may be collected
by the Organization on the manoeuvrability of ships,
RECOGNIZING the manoeuvring capability of ships to be an important
contribution to the safety of navigation,
BELIEVING that the development and implementation of standards for
ship manoeuvrability, particularly for large ships and ships carrying dangerous
goods in bulk, will improve maritime safety and enhance marine environmental
protection,
HAVING CONSIDERED the recommendations made by the Sub-Committee on
Ship Design and Equipment at its forty-fifth session,
1. ADOPTS the Standards for Ship Manoeuvrability the text of which
is set out in the Annex to the present resolution;
2. INVITES Governments to encourage those responsible for the
design, construction, repair and operation of ships to apply the Standards.
ANNEX.
STANDARDS FOR SHIP MANOEUVRABILITY
1.1 The standards should be used to evaluate the manoeuvring
performance of ships and to assist those responsible for the design,
construction, repair and operation of ships to ensure that such ships comply
with the standards.
1.2 It should be noted that the standards were developed for ships
with traditional propulsion and steering systems (e.g. shaft driven ships with
conventional rudders). Therefore, the standards and methods for establishing
compliance may be periodically reviewed and updated by the Organization, as
appropriate, taking into account new technologies, research and development and
the results of experience with the present standards.
2.1 The standards contained in this document are based on the
understanding that the manoeuvrability of ships can be evaluated from the
characteristics of conventional trial manoeuvres. The following two methods can
be used to demonstrate compliance with these standards:
.1 scale model tests and/or
computer predictions using mathematical models can be performed to predict
compliance at the design stage. In this case full-scale trials should be
conducted to validate these results. The ship should then be considered to meet
these standards regardless of full-scale trial results, except where the
Administration determines that the prediction efforts were substandard and/or
the ship performance is in substantial disagreement
with these standards; and
.2 the
compliance with the standards can be demonstrated based on the results of the
full-scale trials conducted in accordance with the standards. If a ship is
found in substantial disagreement with the standards, then the Administration
should take remedial action, as appropriate.
3.1 Notwithstanding the points raised in paragraph 1.2 above, the
standards should be applied to ships of all rudder and propulsion types, of 100
m in length and over, and chemical tankers and gas carriers regardless of the
length, which are constructed on or after [date of adoption].
3.2 In the event that the ships referred to in paragraph 3.1 above
undergo repairs, alterations or modifications which, in the opinion of the
Administration, may influence their manoeuvrability characteristics, the
continued compliance with the standards should be verified.
3.3 Whenever other ships, originally not subject to the standards,
undergo repairs, alterations or modifications which, in the opinion of the
Administration, are of such an extent that the ship may be considered to be a
new ship, then that ship should comply with these standards. Otherwise, if the
repairs, alterations and modifications, in the opinion of the Administration,
may influence the manoeuvrability characteristics, it should be demonstrated
that these characteristics do not lead to any deterioration of the
manoeuvrability of the ship.
3.4 The standards should not be applied to high-speed craft as
defined in the relevant Code.
.1 Length (L) is the length
measured between the aft and forward perpendiculars.
.2 Midship point is the
point on the centreline of a ship midway between the aft and forward perpendiculars.
.3 Draught (Ta)
is the draught at the aft perpendicular.
.4 Draught (Tf)
is the draught at the forward perpendicular.
.5 Mean draught (Tm)
is defined as
Тm =
(Та + Tf /2)
.6 Trim (t) is defined as t = Та - Tf
.7 Δ
- is the displacement
of the ship.
4.2 Standard manoeuvres and associated
terminology
Standard manoeuvres and associated terminology are as defined
below:
.1 the test speed (V) used
in the standards is a speed of at least 90% of the ship's speed corresponding
to 85% of the maximum engine output;
.2 turning
circle manoeuvre is the manoeuvre to be performed to both starboard and port
with 35° rudder angle or the maximum rudder angle permissible at the test
speed, following a steady approach with zero yaw rate;
.3 advance is
the distance travelled in the direction of the original course by the midship
point of a ship from the position at which the rudder order is given to the
position at which the heading has changed 90° from the original course;
.4 tactical diameter is the
distance travelled by the midship point of a ship from the position at which
the rudder order is given to the position at which the heading has changed 180°
from the original course. It is measured in a
direction perpendicular to the original heading of the ship;
.5 zig-zag test
is the manoeuvre where a known amount of helm is applied alternately to either
side when a known heading deviation from the original heading is reached;
.6 the 10°/10°
zig-zag test is performed by turning the rudder alternately by 10° to either
side following a heading deviation of 10° from the original heading in
accordance with the following procedure:
.1 after a steady approach
with zero yaw rate, the rudder is put over to 10° to starboard or port (first
execute);
.2 when the heading has
changed to 10° off the original heading, the rudder is reversed to 10° to port
or starboard (second execute); and
.3 after the rudder has been
turned to port/starboard, the ship will continue turning in the original
direction with decreasing turning rate. In response to the rudder, the ship
should then turn to port/starboard. When the ship has reached a heading of 10°
to port/starboard of the original course the rudder is again reversed to 10° to
starboard/port (third execute);
.7 the first
overshoot angle is the additional heading deviation experienced in the zig-zag
test following the second execute;
.8 the second
overshoot angle is the additional heading deviation experienced in the zig-zag
test following the third execute;
.9 the 20°/20°
zig-zag test is performed using the procedure given in paragraph 4.2.6 above
using 20° rudder angles and 20° change of heading, instead of 10° rudder angles
and 10° change of heading, respectively;
.10 full astern stopping
test determines the track reach of a ship from the time an order for full
astern is given until the ship stops in the water;
.11 track reach is the
distance along the path described by the midship point of a ship measured from
the position at which an order for full astern is given to the position at
which the ship stops in the water;
.12 MCR is the maximum
continuous rating for propulsion power of the ship, expressed in horsepower;
.13 Vmcr is the
ship's speed at MCR;
.14 Fn is Froude
number at the test speed in the trial.
5.1 The standard manoeuvres should be performed without the use of
any manoeuvring aids which are not continuously and readily available in normal
operation.
5.2 Conditions at which the standards apply
In order to evaluate the performance of a ship, manoeuvring trials
should be conducted to both port and starboard and at conditions specified
below:
.1 deep,
unrestricted water;
.2 calm
environment;
.3 full load (summer
load line draught), even keel condition; and
.4 steady
approach at the test speed.
5.3
Criteria*
_______________
* For ships with non-conventional steering and
propulsion systems, the Administration may permit the use of comparative
steering angles to the rudder