Buena Ventura was transferred to the U.S. Navy on 25 July 1918. Assigned the naval registry Identification Number 1335, she was commissioned as USS Buena Ventura at Philadelphia, Pennsylvania on 26 July 1918 with Lieutenant Commander Howard Fitzsimons, USNRF, in command. Buena Ventura was assigned to the Naval Overseas Transportation Service on a U.S. Army account. After loading cargo at Philadelphia, she departed for New York City on 9 August 1918, then left New York in a convoy on 13 August 1918 bound for France. Steaming first to La Pallice and from there to Royan and Bordeaux, she proceeded to Le Verdon-sur-Mer to take on fuel for the return voyage to Philadelphia. Buena Ventura cleared Le Verdon-Sur-mer in ballast on 14 September 1918 as part of a 25-ship convoy bound for the United States. Seven escorts protected the convoy until that evening, after which the convoy continued across the Atlantic Ocean unescorted.
Loss
At about 20:45 on 16 September 1918, the GermansubmarineU-46 came across the unescorted convoy and fired two torpedoes into Buena Ventura. The first struck amidships, directly beneath the flying bridge about below the waterline and tore a hole that measured long by wide. The blast from the explosion coursed upward, splintering the lifeboat suspended in its davits just above and knocking the wireless out of commission. The second torpedo hit in the after end of the empty hold number four. Buena Ventura, mortally stricken, soon slowed in the rising swells, listing to port. Her siren blasted out the submarine warning signal while her after gun fired one shot. After throwing the confidential publications and codes overboard in weighted bags, the crew abandoned their rapidly sinking ship in the four undamaged lifeboats. Her commanding officer — Lt. Cdr. Fitzsimons — remained on board to be sure that everyone who could abandon ship had done so and, when thus assured, stepped into the last boat and ordered it lowered away. That boat, damaged in bumping against the side of the ship due to the Buena Venturas port list, required unceasing efforts to bale out the water that had gained entry through several leaks. Fitzsimons, his executive officer, and the 27 enlisted men in the boat, separated from the other three boats in the darkness and rising seas, steered in the direction of the Spanish coast. On 18 September, the French destroyer rescued 45 of Buena Venturas crew, while on the morning of 20 September, the Spanish coasterLola took Fitzsimons and his remaining sailors on board and landed them at Corunna, Spain on 22 September.
Louis Siegel's name appears in the U. S. Government publication, , with a death date of 27 September 1918, eleven days after the ship was torpedoed. His name is not listed on other records.
