SS Viper was built at the Fairfield Shipbuilding & Engineering Co.'s yard in Govan in 1906 and was 315 feet in length. She had three steam turbines powering the triple screws, making her one of the company's fastest ships with a top speed of 22 knots. 

She served as a troop carrier during the 1st world war, but returned to normal duties in 1919. She was later sold to the Isle of Man Steam Packet Co in 1920 and renamed Snaefell