Etak ("Kate" spelled backwards) was built at the Friedrich Krupp Germaniawerft shipyard in Kiel, Germany, and launched in 1930.

Some of the ship's more colorful owners have been Adolph Dick of the Dick sugar and banking family of New York; Hans-Wilhelm Röhl, co-owner of the Rohl-Connolly Co. (builder of the Port of Los Angeles breakwaters) and investigated in 1942 for pro-Nazi sympathies; aviation pioneer Thomas F. Hamilton; Crane Co. heir Cornelius Crane; renowned Honolulu-based skipper Omer Darr; Stimson Lumber Company scion Harold Miller; Dutch financier (and kundalini yoga teacher) Pieter Schoonheim Samara; and Calisto Tanzi, ex-chairman of the Parmalat group.

Allegations were made that Army officers involved in construction of Pacific air ferry routes and bases prior to the war mismanaged the effort and had improper associations with Röhl, particularly with respect to the proposed charter of his yacht Vega as a survey vessel.

She alternated with other ships on patrol for the great circle route to Hawaii, sailing to and from her station some 500 miles west of Eureka, California.

Juniata was placed out of service at Treasure Island, San Francisco, California, on 1 January 1945, returned to the Maritime Commission, and sold to Thomas Hamilton in June 1945.