▁to ▁Gib ral tar ▁for ▁rep airs . ▁Several ▁months ▁later , ▁the ▁boat ▁returned ▁to ▁service ▁and ▁conducted ▁two ▁pat rol s ▁in ▁the ▁A ege an , ▁s inking ▁another ▁three ▁ca ï ques , ▁a ▁sail ing ▁vessel , ▁and ▁a ▁merchant ▁ship . ▁On ▁ 3 1 ▁May ▁ 1 9 4 4 , ▁S ick le ▁depart ed ▁Mal ta ▁for ▁a ▁pat rol ▁in ▁the ▁A ege an ▁and ▁did ▁not ▁return . ▁It ▁is ▁considered ▁probable ▁that ▁she ▁hit ▁mines ▁on ▁her ▁way ▁back ▁to ▁Mal ta ▁around ▁ 1 6 – 1 8 ▁June ▁ 1 9 4 4 . ▁ ▁Design ▁and ▁description ▁ ▁The ▁S - class ▁sub mar ines ▁were ▁designed ▁to ▁pat rol ▁the ▁restricted ▁waters ▁of ▁the ▁North ▁Sea ▁and ▁the ▁Mediter rane an ▁Sea . ▁The ▁third ▁batch ▁was ▁slightly ▁en larg ed ▁and ▁improved ▁over ▁the ▁preceding ▁second ▁batch ▁of ▁the ▁S ▁class . ▁The ▁sub mar ines ▁had ▁a ▁length ▁of ▁ ▁overall , ▁a ▁beam ▁of ▁ ▁and ▁a ▁dra ug ht ▁of ▁. ▁They ▁disp la ced ▁ ▁on ▁the ▁surface ▁and ▁ ▁sub mer ged . ▁The ▁S - class ▁sub mar ines ▁had ▁a ▁crew ▁of ▁ 4 8 ▁officers ▁and ▁ratings . ▁They ▁had ▁a ▁div ing ▁depth ▁of ▁. ▁ ▁For ▁surface ▁running , ▁the ▁boats ▁were ▁power ed ▁by ▁two ▁ ▁dies el ▁engines , ▁each ▁driving ▁one ▁prop eller ▁sh aft . ▁When ▁sub mer ged ▁each ▁prop eller