USS Housatonic (SP-1697)

El Rio was built for the Morgan Line in 1899 and served as a freighter until the United States Shipping Board took control of the vessel in 1917 for conversion to wartime naval use.

In 1935 the vessel was sold to Atlantic, Gulf & West Indies Lines (Agwilines) continuing freight service until sunk in a collision in 1942.

[6][2] El Rio was intended for service between New York City and Gulf of Mexico seaports of New Orleans and Galveston, Texas.

Housatonic was fitted out for United States Navy service at Tietjen & Lang's shipyard at Hoboken, New Jersey.

Stern ports were cut for launching the mines and the rudder quadrant was raised to give adequate clearance.

The main machinery was overhauled and auxiliary machinery was added for the elevators, for heating the berthing spaces, for refrigerated food storage, for additional fresh water distilling capacity, for magazine sprinklers and galley and washroom plumbing, and enlarged electric generators for lighting and radio communications.

[11] Brazos on 21 December 1932 had been involved in a collision determined to have been caused by mutual fault in fog off Galveston with Eglantine, a vessel owned by the United States, resulting in a lawsuit by Clyde-Mallory Lines regarding a two-year limitation period for such suits resulting in an appellate court ruling that the two year limitation should have applied.

[12][13] In 1935 the ship began operations with Atlantic, Gulf & West Indies Lines (Agwilines) with a signal letter change to WHCB.

[6][11][16] The collision with HMS Archer, an escort carrier transporting aircraft from Norfolk, Virginia to Kingston, Jamaica and suffering from steering and gyrocompass failures, occurred about two and a half hours before midnight.