SS Merion SS " Merion " was an ocean liner built in 1902 for the American Line , a subsidiary line of the International Mercantile Marine ( IMM ) . She also sailed for the Red Star Line and the Dominion Line — both subsidiary lines of IMM — during her passenger career . After the outbreak of World War I she was bought by the British Admiralty and converted to serve as a decoy resembling the Royal Navy battlecruiser . In May 1915 , while posing as " Tiger " in the Aegean Sea , " Merion " was sunk by the German submarine . Career . " Merion " was built by John Brown & Company of Clydebank , Scotland for the American Line , a subsidiary of the International Navigation Company , and launched on 26 November 1901 . The ship was long ( between perpendiculars ) and abeam . She had a gross register tonnage ( GRT ) of 11 , 621 . The ship had twin screw propellers powered by twin triple - expansion steam engines , and , at top speed , could move . As built , " Merion " had accommodations for 150 second - and 1 , 700 third - class passengers . She was a sister ship to . Upon completion , the ship was chartered to the Dominion Line , a subsidiary line of International Mercantile Marine ( IMM ) with which International Navigation had merged in 1902 . The liner sailed for Dominion on her maiden voyage on 8 March 1902 from Liverpool to Boston . After completing eleven voyages on that route , " Merion " was returned to the American Line in March 1903 . The following month she began sailing on the Liverpool – Philadelphia route on which she sailed most of the rest of her passenger career . She was briefly chartered to the Red Star Line in 1907 for one Antwerp – New York voyage . The liner had several mishaps during her passenger career . On 2 March 1903 , an article in " The Washington Post " reported that " Merion " had run aground shortly after leaving Queenstown while en route to Liverpool from Boston . The ship was freed from her perch near Chicago Knoll by the rising tide , but when she got underway again became stuck fast in almost the same spot . At press time , two British Admiralty tugs had been dispatched to free the ship . Almost exactly a year later , " Merion " collided with the steamer " Clan Grant " off Tuskar Rock on 30 March 1904 and was damaged . On 24 December 1912 , " Merion " collided with a tanker off the Delaware coast and sustained damage which included two flooded compartments . The ship was beached below Cross Ledge , but was refloated and made way under her own power back to Philadelphia , after discharging her cargo and passengers . After the outbreak of World War I in Europe , " Merion " was equipped with four guns for defensive purposes . " Merion " was the subject of a protest by the German Consul at Philadelphia , when she docked at that port equipped with those guns , counter to rules regarding armed ships in neutral ports . The still - neutral United States required that the guns be removed before they would allow " Merion " to sail ; her guns were stowed belowdecks when she departed Philadelphia on 5 September 1914 . " Merion " s final voyage on the Liverpool – Philadelphia route began on 31 October , after which she was sold to the British Admiralty . " Merion " was employed as part of a program that disguised ocean liners to resemble Royal Navy capital ships . " Merion " was patterned after the British battlecruiser and deployed in the Mediterranean . For this duty , the liner was equipped with canvas - and - wood replicas of " Tiger " s guns , and her crew had to stow them whenever approached by neutral ships . The ship was also overloaded with ballast to make the ship ride lower in the water to match the profile of the real " Tiger " . On 29 May 1915 , the German submarine , apparently tempted by the prospect of sinking a British battlecruiser , allowed five loaded transports to sail past before launching a torpedo attack on " Merion " . One torpedo from " UB - 8 " struck the liner and exploded , sending some of the " cement and stones " used as ballast into the air . Some of " Merion " s crew that were knocked overboard by the explosion were able to float ashore on nearby Strati Island on remnants of the liner ' s false guns . Despite being severely overloaded , " Merion " did not immediately sink , remaining afloat more than 24 hours before finally succumbing to the attack on 31 May . There are no reports of any deaths during " Merion " s sinking .