Bismarck Class stability
Posted: Mon Nov 22, 2004 9:21 am
In the excellent Bismarck article written by William H. Garzke, Jr. & Robert O. Dulin, Jr. and originally published in Warship International No. 2, 1994, there is a paragraph commenting on the stability of the ship:
"The Germans devoted great attention to the displacement and stability of the Bismarck and Tirpitz. They recognized the need to provide great initial stability, with commensurate resistance to large lists after side compartments were damaged. A disadvantage of this stability was the short rolling period resulting from the large GM. The Bismarck was a lively gun platform and the ship's general behavior at sea was probably rather unpleasant, particularly in following seas, where rolling and yawing motions are coupled. The Bismarck had excessive stability in many respects in that her GM exceeded the "good design practice" standard for GM (at last 5%, but no more than 10%) of the beam. Too much stability results in an unduly "stiff" ship with somewhat unpleasant rolling characteristics which tend to degrade weapon's systems effectiveness."
I don't understand this principle, how can too much stability degrade weapon's systems effectiveness? In his book Müllenheim-Rechberg seems to say the opposite:
"Of special interest is the fact that, in comparison with most large warships of the period, her beam was relatively wide in proportion to her length. This characteristic ran counter to the prevalent desire for more speed, which called for the least beam possible in relation to length. However, Bismarck’s wide beam seemed to work to her overall advantage, because it lessened any tendency to roll in a seaway and, thus, increased her value as a gun platform."
Any comments on this?
"The Germans devoted great attention to the displacement and stability of the Bismarck and Tirpitz. They recognized the need to provide great initial stability, with commensurate resistance to large lists after side compartments were damaged. A disadvantage of this stability was the short rolling period resulting from the large GM. The Bismarck was a lively gun platform and the ship's general behavior at sea was probably rather unpleasant, particularly in following seas, where rolling and yawing motions are coupled. The Bismarck had excessive stability in many respects in that her GM exceeded the "good design practice" standard for GM (at last 5%, but no more than 10%) of the beam. Too much stability results in an unduly "stiff" ship with somewhat unpleasant rolling characteristics which tend to degrade weapon's systems effectiveness."
I don't understand this principle, how can too much stability degrade weapon's systems effectiveness? In his book Müllenheim-Rechberg seems to say the opposite:
"Of special interest is the fact that, in comparison with most large warships of the period, her beam was relatively wide in proportion to her length. This characteristic ran counter to the prevalent desire for more speed, which called for the least beam possible in relation to length. However, Bismarck’s wide beam seemed to work to her overall advantage, because it lessened any tendency to roll in a seaway and, thus, increased her value as a gun platform."
Any comments on this?