When a ship rolls heavily in a sea-way she is subjected to racking stresses which tend to distort her aides and upper deck, and a combination of both pitching and rolling subjects her to torsional stresses which tend to twist her hull about its fore- and -aft axis .
Xa inqanawa iqwengqeleka ngamandla elwandle ingaqhekeka nto leyo edla ngokubangela ngokulahleka kwezixhobo zoncedo ezikwidekhi engasentla, kwaye ukudibana kwezinto ezihla zinyuka neziqengqelekayo kuyibangela ukuba ijijeke isiqu kangangokuba phantse umva uze ngaphambili umphambili uye ngasemva.