 On 4 July, the "U-539", attacked the 10,195 ton American Type T2 tanker "Kittanning", about 40 miles northeast of Cristóbal, Panama, and hit her with three torpedoes, ripping a hole 65 feet long and 20 feet high on her starboard side.The crew of 74 abandoned ship in four lifeboats, but the tanker remained afloat.Two Coast Guard cutters, and arrived to pick up the survivors and take the ship in tow to Cristobal.