German submarine U-2513 was a Type XXI U-boat of Nazi Germany's Kriegsmarine, that was operated by the United States Navy for several years after World War II.

A year later, August 1946, U-2513 began an extensive overhaul in Charleston, South Carolina, which was completed late in September.

The Greater Underwater Propulsion Power Program (GUPPY) would be initiated because of the results of these tests.

The sub went 440 feet (130 m) below the surface with the President on board, and a demonstration was made to him of the German schnorchel (a specialized submarine snorkel).

She remained there until 8 September when she began six weeks of operations from Portsmouth and New London, Connecticut, under the auspices of the Commander, Submarines, Atlantic Fleet.

In mid-June 1949, the submarine moved from Key West north via Norfolk, Virginia, to Portsmouth, New Hampshire, where she was placed out of service in July 1949.