STIFF SHIPS
- Stiff ships are ships having comparatively higher GM( Metacentric Height) for her type ,size and nature(type refers to type of vessel and nature refers to peculiarities of the vessel)
- Angle of roll and Period of roll is small
- Violent and irregular rolling which makes the people on board uncomfortable due to jerky movements
- Due to violent and irregular rolling severe stresses set up on hull.
- Cargo shifts on Stiff ship depending on the type of cargo .If it is a general cargo vessel the cargo is likely to shift due to violent rolling. But if it is a bulk cargo it won't shift much as the period of roll is small.
- Chances of ship getting unstable during the passage due consumption of fuel ,fresh water etc is very less
- As Stiff ships have higher GM they can withstand loss of GM due to occurances like flooding.
- It allows only very little transverse shift of cargo. So the list caused by this is very less.
TENDER SHIPS
- Tender ships are ships having very low GM of her type ,size and nature.
- High angle of roll and Period of roll
- Regular and smooth rolling which keeps the people onboard comfortable.
- Very little stresses set up on hull because of regular and smooth rolling
- Cargo shifts on tender ships depending upon the type of cargo. General Cargo is less likely to shift in a tender ship due to smooth and regular rolling, but the bulk cargoes will shift and create danger due to high period of roll.
- There are chances for the vessel getting unstable during the voyage due to consumption of fresh water or fuel.
- Due to less GM the chances of vessel getting unstable due to flooding is pretty high.
- Transverse shift of cargo is high and list caused by such a shift is very large.
CONCLUSION
From the above explanation it is clear that neither stiff ship nor tender ship is perfect. GM Shouldn't be too large or too less.An intermediate GM is much better.Also ships can be stiff or tender depending on the type of cargo that they are carrying.
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