 Mainz was ordered under the contract name Ersatz Jagd and was laid down in 1907 at the AG Vulcan shipyard in Stettin . She was launched on 23 January 1909 and christened by the mayor of Mainz , Karl Emil <unk> , after which fitting @-@ out work commenced . She was commissioned into the High Seas Fleet on 1 October 1909 . The ship was 130 @.@ 5 meters ( 428 ft ) long overall and had a beam of 14 m ( 46 ft ) and a draft of 5 @.@ 58 m ( 18 @.@ 3 ft ) forward . She displaced 4 @,@ 915 t ( 4 @,@ 837 long tons ; 5 @,@ 418 short tons ) at full combat load . Her propulsion system consisted of two sets of AEG @-@ Curtiss steam turbines driving two 3 @.@ 45 @-@ meter ( 11 @.@ 3 ft ) propellers . They were designed to give 19 @,@ 000 shaft horsepower ( 14 @,@ 000 kW ) . These were powered by fifteen coal @-@ fired Marine water @-@ tube boilers . These gave the ship a top speed of 26 knots ( 48 km / h ; 30 mph ) . Mainz carried 1 @,@ 010 t ( 990 long tons ; 1 @,@ 110 short tons ) of coal that gave her a range of approximately 3 @,@ 630 nautical miles ( 6 @,@ 720 km ; 4 @,@ 180 mi ) at 14 knots ( 26 km / h ; 16 mph ) . Mainz had a crew of eighteen officers and 349 enlisted men . 
