German Submarine U-171 - Service History

Service History

U-171 departed Kiel on its first operational patrol on 17 June 1942, at the end of which it was to return to Lorient, where it would be based for future sorties.

On 26 July 1942, the submarine sank a 4,351 ton Mexican general cargo merchant ship, the SS Oaxaca at 28°23′N 96°08′W / 28.383°N 96.133°W / 28.383; -96.133 (Oaxaca (ship)) off Corpus Christi, Texas. The ship was at the time en-route from New Orleans to Tampico via Veracruz. The first spread of two torpedoes missed the ship, but a second spread, also of two torpedoes, was successful when one hit the port side near the fore of the ship. Six of the ship's crew of 45 died.

On 1 August 1942, while on patrol in the Gulf of Mexico, U-171 came under attack from a U.S. Coast Guard J4F-1 Widgeon aircraft, causing it little damage. However, for decades it was believed that the U-boat attacked that day was U-166, and the credit for the sinking of U-166 went to that aircraft.

In 2001, the wreckage of U-166 was discovered just a short distance from its last victim, the SS Robert E. Lee, meaning that the credit for the sinking of U-166 should have gone to the U.S. Navy patrol craft, PC-566, which had reported that they believed they were successful in their depth charge attack on the submarine following the U-boat's successful torpedoing of the Robert E. Lee, but were believed by investigating officials to have missed.

Having not been sunk, as had been believed by the Allies, the submarine continued its patrol. On 13 August 1942 it sank the 6,779 ton US tanker SS R. M. Parker Jr. at 28°50′N 90°42′W / 28.833°N 90.7°W / 28.833; -90.7 (R.M. Parker Jr. (ship)). The ship, which was carrying water ballast, was struck by two torpedoes; the submarine then surfaced and fired five rounds from its deck gun into the wreck. The whole crew of 44 survived, being picked up eight hours later by the United States Coast Guard auxiliary USS Pioneer.

On 4 September 1942, the submarine had its final success, the Mexican tanker SS Amatlan, 6,511 tons; again in ballast, at 23°27′N 97°30′W / 23.45°N 97.5°W / 23.45; -97.5 (Amatlan (ship)). This ship had evaded three spreads of two torpedoes each before being hit by a torpedo fired from U-171's stern tube. There were 10 dead and 24 survivors.

U-171 was sunk at 13:00 hours on 9 October 1942 in the Bay of Biscay near Lorient, in position 47°39′N 03°34′W / 47.65°N 3.567°W / 47.65; -3.567 (U-171 (ship)), by a mine. There were 22 dead and 30 survivors, including Commander Pfeffer (1914–1966).

The wrecked submarine was classified as a "military cemetery" in 1999 by the French authorities: divers are then warned that going inside the boat is strictly forbidden.