 UB @-@ 7 was laid down by Germaniawerft in Kiel on 30 November . As built , UB @-@ 7 was 28 @.@ 10 metres ( 92 ft 2 in ) long , 3 @.@ 15 metres ( 10 ft 4 in ) abeam , and had a draft of 3 @.@ 03 metres ( 9 ft 11 in ) . She had a single 59 @-@ brake @-@ horsepower ( 44 kW ) Daimler 4 @-@ cylinder diesel engine for surface travel , and a single 119 @-@ shaft @-@ horsepower ( 89 kW ) Siemens @-@ Schuckert electric motor for underwater travel , both attached to a single propeller shaft . Her top speeds were 6 @.@ 47 knots ( 11 @.@ 98 km / h ; 7 @.@ 45 mph ) , surfaced , and 5 @.@ 51 knots ( 10 @.@ 20 km / h ; 6 @.@ 34 mph ) , submerged . At more moderate speeds , she could sail up to 1 @,@ 650 nautical miles ( 3 @,@ 060 km ; 1 @,@ 900 mi ) on the surface before refueling , and up to 45 nautical miles ( 83 km ; 52 mi ) submerged before recharging her batteries . Like all boats of the class , UB @-@ 7 was rated to a diving depth of 50 metres ( 160 ft ) , and could completely submerge in 33 seconds . 
