She went gallantly into action, rounded the point, and blazed away at the rebel batteries, but the latter were not idle, and all the guns that could be brought to bear—rifled and smooth bore — opened on her. Her tiller ropes were shot away, and she got some heavy shot into her sides. The pilot was killed at the wheel, and her commander took his place. All the men at the wheel were wounded, but Lieut. Bache escaped unharmed.When the Cincinnati took a direct hit and her steering was knocked out, her captain knew she was doomed. He was able to drive the ship onto the bank, where she was tied to allow for an easy evacuation. But before the men could be got on shore the ropes came loose and the Cincinnati was pushed out into the river again. She sank in 13 feet of water. Those who could swim jumped over and headed for shore, but many were trapped on board the ship. Four of the crew, Landsman Thomas E. Corcoran, Boatswain's Mate Henry Dow, Seaman Thomas Jenkins, and Seaman Martin McHugh, began helping their fellow crew members escape. They helped them swim to shore. For those badly wounded from the Confederate fire, they returned to the sinking ironclad and repaired a small boat, and loaded the casualties on board. These four swimmers were awarded the Medal of Honor for their conduct. The ship suffered 40 casualties in this disaster. She would later be raised in August, 1863 and return to service
She started up the river, as she made a great deal of water, rounded again the point of the peninsula opposite Vicksburg, and was struck by a plunging 10-inch smooth-bore or 7-inch rifled shot; she then commenced to sink, and her captain ran her inshore, where she sank to her hammock netting. The officers and crew saved nothing.