A dispatch dated 31 January 1941 expressed the Chief of Naval Operations' desire that Evelyn and Carolyn "be given a preliminary conversion to AK (cargo ship) in the shortest possible time."

A letter from the Chief of the Bureau of Ships elaborated on the "shortest possible time," when it stated on 12 February that the conversion and outfitting of the vessels was desired "by 1 March 1942."

They were to use their old identities when communicating with friendly vessels and stations; if enemy ships should challenge, reply should be made in accordance with International Procedure, using the identification SS Vill Franca, of Portuguese Registry, callsign CSBT.

At the outset, all connected with the program apparently harbored the view that neither ship "was expected to last longer than a month after commencement of [her] assigned duty."

According to the projected scenario, the submarine, having deemed the tramp unworthy of the expenditure of more torpedoes, would surface to sink the crippled foe with gunfire.

The U-boat, on the surface, began stalking Atik at 17:00, and at 19:37 fired one torpedo from 700 yd (640 m) away which struck the ship on her port side, under the bridge.

The Duty Officer in the Control Room had not been informed as to the secret nature of Carolyn, and consequently his only action was to forward the dispatch to Commander-in-Chief, United States Fleet (COMINCH).

A veritable hail of .50-caliber machine gun fire, though, ricochetted around the U-boat's decks as she put on speed to escape the trap into which Hardegen had fallen.

Gradually, the U-boat pulled out of range behind the cover of a smoke screen emitted by her straining diesels, and her captain assessed the damage.

Early the next morning, an Army bomber was sent to search the area from which Carolyn had sent her distress message; the destroyer Noa and the tug Sagamore were sent to assist.

The tug and the destroyer encountered such heavy weather that Sagamore was recalled; Noa searched the area until fuel shortage compelled her to return to New York on 30 March.

Asterion had intercepted the distress messages from Atik and proceeded directly to the area, Lieutenant Commander Legwen deeming his orders "sufficiently broad to proceed immediately to her assistance," but Asterion encountered difficulties with her steering gear, and only continued the search for 24 hours before being forced to put into Hampton Roads for repairs.

Twelve days later, CESF reported all known details to COMINCH on the "suspected sinking of the SS Carolyn," and concluded: "...it is believed that there is very little chance that any of her officers and crew will be recovered.