HMS Niger was a torpedo gunboat launched in 1892, converted to a minesweeper in 1909, and sunk in 1914 by the German submarine SM U-12 near Deal.
Niger
SM U-12 was a German submarine, built in 1911 and sunk off Scotland in 1915. It was the first submarine to launch a plane at sea.
U-12 was a Type U 9 U-boat built for the Imperial German Navy. Her construction was ordered on 15 July 1908 and her keel was laid down by Kaiserliche Werft in Danzig. She was launched on 6 May 1910 and commissioned on 13 August 1911.
SM U-12 with seaplane on deck
Submarine U-12 on left