High Quality Content by WIKIPEDIA articles HMS Hydra (Pennant Number A144) was a Royal Navy deep ocean hydrographic survey vessel, the third of the original three of the Hecla class. The ship was laid down as yard number 2258 on 14 May 1964 at Yarrow Shipbuilders, at Scotstoun on the River Clyde and launched on 14 July 1965 by Mary Lythall, wife of the then Chief Scientist (Royal Navy), Basil W Lythall CB (1919-2001). She was completed and first...