Original caption: Coast Guard Cutter sinks sub. Heaved up from below by the force of a depth charge, the Nazi U-Boat 175 breaks surface as the U.S. Coast Guard Cutter SPENCER, guns ablaze, bears down on it, full speed ahead. The submarine was sunk on April 17, 1943, in the North Atlantic, as it was approaching inside a convoy of ships ready to attack with torpedoes.

National Archives Identifier: 205574156 https://catalog.archives.gov/id/205574156
Original caption: Coast Guard Cutter sinks sub. Coast Guardsmen on the deck of the U.S. Coast Guard Cutter SPENCER watch the explosion of a depth charge which blasted a Nazi U-Boat’s hope of breaking into the center of a large convoy. The depth charge tossed from the 327-foot cutter blew the submarine to the surface, where it was engaged by Coast Guardsmen. Ships of the convoy may be seen in the background.

National Archives Identifier: 205574168 https://catalog.archives.gov/id/205574168
USCGC Spencer (WPG-36), a 327-foot Treasury-class cutter, is shown above sinking KMS U-175, in position 47.53N, 22.04W, by depth charges and gunfire some 500 miles SW of Ireland. Assigned to 10. Flottille under skipper Kptlt. Heinrich Bruns, the Type IXC boat had chalked up over 40,000 tons of shipping before Spencer ruined her paint job. Some 41 Germans were picked up from the ocean that day and made POWs for the rest of the war while 13 rode the submarine to the bottom.

Official Caption: “NAZI SUBMARINE SUNK BY THE FAMED CUTTER SPENCER: Effect of the U.S. Coast Guard Cutter SPENCER’S fire are visible in this closeup shot of the U-Boat, taken as the battle raged. The Nazi standing by the stanchion amidships disappeared a moment after this picture was taken by a Coast Guard photographer. The U-Boat had been trying to sneak into the center of the convoy.” Date: 17 April 1943 Photo No.: 1512 Photographer: Jack January? Description: The “Nazi” mentioned in the above caption was probably in fact a member of the Coast Guard boarding team–one of the first Americans to board an enemy man-of-war underway at sea since the War of 1812.

Official Caption: “OFF TO RESCUE THEIR BEATEN FOES: A pulling boat leaves the side of a Coast Guard combat cutter to rescue Nazi seamen struggling in the mid-Atlantic after their U-Boat had been blasted to the bottom by the cutter’s depth charges. Two Coast Guard cutters brought 41 German survivors to a Scottish port.” Date: 17 April 1943 Photo No.: 1516 Photographer: Jack January Description: The men in this pulling boat were in fact a trained boarding team led by LCDR John B. Oren (standing in the stern and wearing the OD helmet) and LT Ross Bullard (directly to Oren’s left). With the assistance of the Royal Navy they had practiced boarding a submarine at sea in order to capture an Enigma coding machine and related intelligence material. They were forced to take a pulling lifeboat when the Spencer’s motor lifeboat was damaged by friendly fire.
As for Spencer, named for President Tyler’s T-secretary, she would survive the war and go on to complete a 40-year career.
Decommissioned 23 January 1974 she was used for a further six years as an Engineering Training School and berthing hulk at the CG Yard in Maryland then fully decommissioned on 15 December 1980 and sold the following year to the North American Smelting Company of Wilmington, Delaware.
Her name is currently carried by a 270-foot Bear-class high endurance cutter (WMEC 905), which has been with the Coast Guard since 1986, a comparatively paltry 35 years.