Influence of Metacentric Height
If the metacentric height (GM) of a ship is large,
the righting arms that develop, at small angles of heel,
will be large. Such a ship is “stiff” and will resist roll.
However, if the metacentric height of a ship is small,
the righting arms that develop will be small. Such a
ship is tender and will roll slowly.
In ships, large GM and large righting arms are
desirable for resistance to damage. However, a
smaller GM is sometimes desirable for a slow, easy
roll that allows for more accurate gunfire; therefore,
the GM value for a naval ship is the result of
compromise.