STABILITY

Question 1

Genral stability criteria

Answer 1

1. Gm should be more than or equal to 0.15m . In timber ship 0.05m
2. Max GZ should be at or beyond 30 degree.
   3.At 30 degree GZ should be more than or equal to 0.2m
   4.Area under GZ curve from 0 to 40 degree or angle of down flooding which ever is least must be more than or equal to 0.09m RAD
   5.Area under GZ curve from 30 to 40 degree or angle of down flooding which ever is least must be more than or equal to 0.03m RAD
   6.Area between 0 to 30 degree 0.055 m Rad

Question 2

Grain stability criteria

Answer 2

1.The initial metacentric height, after correction for the free surface effects of liquids in tanks, shall be not less than 0.30 meter
2.The angle of heel due to the shift of grain shall not be greater than 12° or in the case of ships constructed on or after 1 January 1994 the angle at which the deck edge is immersed, whichever is the lesser
3.In the statical stability diagram, the net or residual area between the heeling arm curve and the righting arm curve up to the angle of heel of maximum difference between the ordinates of the two curves, or 40° or the angle of flooding (01), whichever is the least, shall in all conditions of loading be not less than 0.075 metre-radians
4.Before loading bulk grain the master shall, if so required by the Contracting Government of the country of the port of loading, demonstrate the ability of the ship at all stages of any voyage to comply with the stability criteria required by this section.
5.After loading, the master shall ensure that the ship is upright before proceeding to sea.

Question 3

Bulk carrier damage stability

Answer 3

1)Bulk carriers of 150 m in length and upwards of single side skin construction, designed to carry solid bulk cargoes having a density of 1,000 kg/m3 and above, constructed on or after 1 July 1999 shall, when loaded to the summer load line, be able to withstand flooding of any one cargo hold in all loading conditions and remain afloat in a satisfactory condition of equilibrium, as specified in paragraph 3.

2) Bulk carriers of 150 m in length and upwards of single side skin construction, carrying solid bulk cargoes having a density of 1,780 kg/m3 and above, constructed before 1 July 1999 shall, when loaded to the summer load line, be able to withstand flooding of the foremost cargo hold in all loading conditions and remain afloat in a satisfactory condition of equilibrium, as specified in paragraph 3. This requirement shall be complied with in accordance with the implementation schedule specified in regulation 3.

3) Subject to the provisions of paragraph 6, the condition of equilibrium after flooding shall satisfy the condition of equilibrium laid down in the annex to resolution A.320(IX), Regulation equivalent to regulation 27 of the International Convention on Load Lines, 1966, as amended by resolution A.514(13). The assumed flooding need only take into account flooding of the cargo hold space. The permeability of a loaded hold shall be assumed as 0.9 and the permeability of an empty hold shall be assumed as 0.95, unless a permeability relevant to a particular cargo is assumed for the volume of a flooded hold occupied by cargo and a permeability of 0.95 is assumed for the remaining empty volume of the hold.

Question 4

Damage stability criteria

Answer 4

1.Final water line after flooding is below the lower edge of any deck
opening through which progressive downflooding could take place.
2 Final angle of heel does not exceed 15º (17º if deck edge not emerged).
3. The metacentric height in the flooded condition is positive.
4. The residual stability after flooding should be as follows ~
Range of stability of at least 20º.
Max GZ not less than 0.1 m.
Area under GZ curve of at least 0.0175 m.r.