At 06.43 hours on 2 Mar, 1943, U-634 fired a spread of four torpedoes at the Meriwether Lewis (Master John Edward Beal), a straggler from convoy HX-227, and hit her with one torpedo after eight minutes. The ship sank bow first following two coups de grâce at 07.52 and 09.05 hours, after a heavy detonation in the forward part of the ship when the cargo of ammunition blew up.
Earlier the ship had been attacked and missed by U-759 (Friedrich), which then had troubles with the diesel engines and led the other U-boat to her target.
The US Coast Guard cutter USS Ingham (WPG 35) searched the area for two days and only located a trail of automobile tires that stretched for 30 miles. All eight officers, 36 crewmen and 25 armed guards (the ship was armed with one 4in, one 3in and eight 20mm guns) were lost.