german submarine german submarine type boat nazi_germany kriegsmarine world war keel laid december launched july commissioned kriegsmarine september command succeeded commanding officers years conducted seven war patrols august november command sinking ships totaling gross register tons grt damaging totaling grt patrol training vessel bring new boat crews standard later sunk accident march stricken august construction design construction ordered kriegsmarine april violation treaty versailles keel laid shipyard bremen yard number december months construction launched july commissioned kriegsmarine type submarine september command design like type submarines displaced tonnes long tons surfaced long tons submerged overall length pressure hull propulsion consisted man cylinder stroke diesel engines totaled maximum rpm submarine equipped electric motors totaled shp maximum rpm power plants gave maximum speed knots mph surfaced knots mph submerged range nmi traveling knots mph surface nmi knots mph submerged boat test depth deep having hull crushed armament consisted torpedo tubes located bow stern torpedoes board mines mines equipped gun deck gun rounds anti aircraft defenses consisted anti aircraft gun service history patrol war patrol took place august september september sailing mouth sank ton freighter success patrol second patrol second war patrol took place november december effort instructed lay minefield near port city route bristol sank ships ton dutch tanker ton british freighter laid minefield returned port germany minefield immediate success sank ton british freighter days laid patrol sortie took place february march instructed lay mines british naval base portsmouth laid minefield went sink ships tons fourth patrol fourth war patrol took place june july sent western approaches turned average performance sinking ships totalling tons irish government sought explanation germany sinking neutral greek ship entire cargo comprised grain exclusive consumption sailing argentina cargo wheat torpedoed sunk south west ireland fifth patrol fifth war patrol took place august september productive august sank ships tons september found tracked convoy darkness early morning september attacked convoy claimed large tons sunk caused damage ton tanker bringing total patrol ships tons postwar analysis credited sinking ton dutch freighter damaging ton british freighter combined earlier brought total ships tons return awarded knight cross work sixth patrol sixth final war patrol took germany heavy seas foul weather sank half ship tons shared credit sinking november returned germany turned training command proceeded command fate sank accident march boat pier training exercise boat passed dummy freighter target practice commander training failed note position stationary freighter boat conning tower ripped water flooded control room compartments remained intact crew escaped slowly water pressure boat swimming surface boat raised march stricken august submarine crew suffered casualties career took june summary raiding history
German submarine U-28 (1936)