"U-570" spent three weeks at Hvalfjörður, being repaired and taking short sea trials to test the engines and steering. Between 23 and 26 September, she was carefully inspected by two US Navy officers who had been sent from the United Kingdom to Iceland for that purpose; one of the submarine's G7a torpedoes was off-loaded, handed over to the Americans, and later sent to the United States. An eyewitness recalled that at one point, a Hudson bomber flew low over "U-570" and HMS "Hecla", signalling with a Morse lamp, "This ****** is mine."