Built in 1945 by Everett-Pacific Shipbuilding of Everett, Washington as YTL-561 for the United States Navy.
In 1946, she was acquired by the General Construction Company of Seattle, Washington. Where the tug was renamed as the Ruby X.
The tug was later sold and renamed as the Pi Ken.
The tug was later acquired by Island Tug and Barge of Seattle, Washington, where she was renamed as Helen S.
In 2007 she was acquired by Stephen Tate of Suquamish, Washington, where the tug's name was returned to Ruby X.
In 2010, the tug was again acquired by Island Tug and Barge of Seattle, Washington, where her name reverted to Helen S.
In 2015 she was acquired by Northwest Marine Equipment Leasing of Anacortes, Washington, where the tug retained its name.