What are the factors affecting ship stability?

What are the factors affecting ship stability?

Stability overview Stability is determined by the force of buoyancy provided by the underwater parts of a vessel, coupled with the combined weight of its hull, equipment, fuel, stores and load. These forces can also be adversely affected by the prevailing weather conditions and sea-state.

What are the conditions needed for stability?

Intact conditions

• Lightship or Light Displacement.
• Full load departure or full displacement.
• Standard condition.
• Light arrival.

What is the parameter of ship’s stability?

A ship’s stability, as seen above, can be directly commented on, by the value of its metacentric height (GM). GM > 0 means the ship is stable. GM = 0 means the ship is neutrally stable. GM < 0 means the ship is unstable.

What are the two major types of stability that concern surface ships?

That there are two major types of stability that concern surface ships- Intact Stability and Damaged Stability.

What is the reason why ro ro cargo affect the stability of the ship?

Due to absence of subdivisional bulkheads, the water progresses along the length of the ship. This not only causes the ship to lose its inherent buoyancy, but adversely affects its stability because of increasing free surface effect.

What is damage stability?

marine. Stability of a flooded ship. When water runs into a ship following an accident, different scenarios can take place. The ship may sink due to flooding of so many compartments that there is not enough buoyancy to keep the vessel afloat.

What are the three stability conditions?

There are three types of equilibrium: stable, unstable, and neutral.

What are the 2 conditions for stability?

To quantify equilibrium for a single object, there are two conditions:

• The net external force on the object is zero: ∑iFi=Fnet=0.
• The net external torque, regardless of choice of origin, is also zero: ∑iri×Fi=∑iτi=τnet=0.

What is the dynamic stability of a ship?

The dynamical stability of a ship at a given angle of heel is defined as the work done in heeling the ship to that angle very slowly and at constant displacement, i.e., ignoring any work done against air or water resistance.

What is Ship Stability list?

marine. A steady angle of heel created by forces within the ship. For example, when the ship is inclined due to her asymmetric construction, or by shifting a weight transversely within the ship. The list reduces of ship’s stability.

How do you check the statical stability of ships?

The statical stability of ships is checked by comparing the righting-arm curve with the curves of heeling arms. A heeling arm is calculated by dividing a heeling moment by the ship displacement force. In general, a heeling-arm curve intersects the righting-arm curve in two points that correspond to positions of statical equilibrium.

How does weight affect the stability of ships?

If the ship is undamaged and floating in calm water, the weights are balanced and the ship is stable. However, the movement of weight on the ship causes a change in the location of the ship’s center of gravity, and thereby affects the stability of the ship.

What is the history of ship-stability?

His book, Bemastung und Takelung der Schiffe was first published in Berlin, in 1903, and it contained the first proposal for a ship-stability criterion. In 1933, Pierrottet (see Pierrottet, 1935) wrote in a publication of the test basin in Rome that the stability of a ship must be assessed by comparing the heeling moments with the righting moment.

What are the regulations for the safe design of ships?

The safe design of a ship is primarily regulated in SOLAS chapter II-1, parts A (General) , A-1 (structure of ships) and B (subdivision and stability), the 1966 Load Line Convention and the 1988 Protocol relating thereto, the 1969 Tonnage Measurement Convention and the International Code on Intact Stability, 2008.