Cyril Percy Ryan

Captain Cyril Ryan was the inventor of the hydrophone and captain of HMS Tarlair, naval research and experimental station.

During World War One, Aberdour on the Firth of Forth became home to a research station of great military and scientific significance. On a spit of land near to the village were several huts and temporary buildings that together made up Hawkcraig Experimental Station, usually known as HMS Tarlair after the fishing boat originally assigned to the base.

It was here that the British navy developed a range of tools and technologies to aid in the war effort, the best known of which was the hydrophone – an instrument used for the detection of enemy U-boats. Tarlair’s commanding officer during the war was Captain Cyril Percy Ryan, who had come out of retirement in order to develop the hydrophone technology and train sailors in how to use it.

Born in County Kilkenny, Ireland in 1874, Ryan joined the navy in 1889 and as an, ‘excellent all round officer’, worked his way up to the position of Commander. He was placed on the retired list in 1911 but during World War One, Ryan was called upon to work with the Hydrophone Service.

The first models that he developed were shore-based instruments for controlling minefields. In 1915, he developed a hydrophone for use from the shore, noting in his official report that a submerged submarine was easier to hear at a given horsepower than a surfaced one, that iron ships were more easily heard than wooden ones and that paddleboats were the easiest vessel to rule out.

In 1917 he was appointed to HMS Tarlair to lead the Hawkcraig Experimental Station. In total, several thousand permanent and temporary personnel were assigned to Tarlair over the course of the war before operations came to a conclusion in 1919. Ryan remained in Tarlair until 1920 when he was transferred to the Torpedo Training School, HMS Vernon, in Portsmouth where he remained until 1921.

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HMS Tarlair Heritage Project