USS Niagara may refer to:
The first USS Sturdy (SP-82) was a patrol boat acquired by the U.S. Navy for the task of patrolling the coastal waters of the U.S. East Coast during World War I. Her primary task was to guard the coastal area against German submarines by tending to antisubmarine nets in New York harbor.
USS Emeline (SP-175) was a yacht acquired by the U.S. Navy during World War I. She was outfitted with military equipment, including 3-inch guns, and was commissioned as a patrol craft, assigned to protect shipping in the North Atlantic Ocean. She saved the lives of survivors of shipwrecks, and provided escort protection from German submarines for commercial ships. Post-war she was sold to the highest bidder, who had the yacht sail to San Diego, California, for delivery.
USS Felicia is a name used more than once by the U.S. Navy:
USS Wacondah (SP-238) was an advanced-design yacht acquired by the U.S. Navy during World War I. She was outfitted as an armed patrol craft assigned to guard the New York City harbor against German submarines and to provide escort protection to commercial ships. Post-war she was sold and continued her maritime career as the yacht Intercolonial.
USS Joyance (SP-72) was an armed yacht that served in the United States Navy as a patrol vessel from 1917 to 1919.
USS Riette (SP-107) was an armed motorboat that served in the United States Navy as a patrol vessel from 1917 to 1919.
The third USS Mohican (SP-117), later USS SP-117, was an armed yacht that served in the United States Navy as a patrol vessel from 1917 to 1919.
USS Hoqua (SP-142) was an armed yacht that served in the United States Navy as a patrol vessel from 1917 to 1919.
USS Remlik (SP-157) was a yacht acquired by the U.S. Navy during World War I. She was converted into an armed patrol craft and assigned to protect ships from German submarines in the North Atlantic Ocean. Post-war she was decommissioned, stripped of naval ordnance and sold in Norfolk, Virginia.
USS Hopestill (SP-191) was a United States Navy patrol vessel in commission from 1917 to 1919.
USS Aileen—a yacht built in 1896 at the Delaware River Iron Ship Building and Engine Works shipyard in Chester, Pennsylvania, by John Roach & Sons—was purchased by the Navy on 28 April 1898; converted for naval service by the New York Navy Yard; and commissioned there on 14 May 1898.
USS Surf (SP-518) was a steam yacht that was offered to the United States Navy in 1917 but was never accepted.
USS Cigarette (SP-1234) was a patrol vessel that served in the United States Navy from 1917 to 1919.
USS Arcady (SP-577) was a United States Navy patrol vessel in commission from 1917 to 1919.
USS Owaissa (SP-659) was a United States Navy patrol vessel in commission from 1917 to 1919.
USS Rhebal (SP-1195) was a United States Navy patrol vessel in commission from 1917 to 1919.
The first USS Ardent (SP-680) was a United States Navy patrol vessel and minesweeper in commission from 1917 to 1921. Acquired upon the entry of the United States into World War I, the ship served in New England during the war, and was sold back into private ownership in 1921.
USS Linta (SP-721) was a United States Navy patrol vessel in commission from 1917 to 1919.
USS Elfrida, later USS Elfrida (SP-988), was a United States Navy patrol vessel in commission from 1898 to 1918. She served in the Spanish–American War and World War I.
United States