Ship Stability

Rajeev Jassal
Rajeev Jassal Master

I am sure you must have already gone through the good books of basic stability. The one written in the easiest language is that written by Capt Subramanium.

But I completely understand that sometimes the concepts are not easy to grasp.

I have lined up few stability topics to write and you will get

Rajeev Jassal
Rajeev Jassal Master

When taking a sight by sextant, the important thing is the angle between the position lines.

So if we are taking the Sun sight, we need two position lines separated by as close as possible to 90 degrees. This is done by taking first sight in the morning and calculating it by Long by Chron method. T

Hi,

If the rolling is undamped then yes each phase of rolling will be same. However, in real scenario of damped rolling, as the damping forces in each phase are likely to be different the behavior in each phase is going to be different. Rolling period on the other hand is defined as time for c

Rajeev Jassal
Rajeev Jassal Master

If there aren't any limitations for loading, it does not really matter so much if the vessel will have Sag or Hog till the time stresses are below limits.

Off course it is always better to have minimum stresses on ship. So keeping this in mind, we should spread the load so that we neither have

Rajeev Jassal
Rajeev Jassal Master

When lifting a heavt lift, Why does GM reduces ? GM reduces because of shift of center of gravity of the ship. In fact this is not only the case of lifting heavy lift alone. Center of gravity of the ship would change each time

  • a weight is added (loaded) to the ship
  • a weight is reduced&

Rajeev Jassal
Rajeev Jassal Master

Testing requirements of the approved loadicator includes testing on board by the ship staff and testing by the classification society of the ship.

Testing by ship staff

Each ship is given the test conditions by the class before approving the loadicator. At least every 3 months, ship staff n

Rajeev Jassal
Rajeev Jassal Master

Roll period is how quickly a vessel return to upright position while rolling. So it is the time a ship takes from upright position to going to a particular angle on port side and then going to a angle on starboard side and then again returning back to upright posit

Rajeev Jassal
Rajeev Jassal Master

The block coefficient of a ship is the ratio of the underwater volume of ship to the volume of a rectangular block having the same overall length, breadth and depth.

Let us make this more clear.

Let us say a vessel has a draft equal to 'd' meters. The ship's underwater volume will be a