At 19.25 hours on 28 Apr, 1941, U-96 fired three single torpedoes at three tankers in convoy HX-121 south of Iceland and reported the sinking of two tankers with 18.000 tons and damaging another with 6000 tons after observing three hits. The tankers Oilfield and the Caledonia were sunk and the freighter Port Hardy was hit and sunk after the torpedo had missed the intended target.

Seven crewmen of the 35 men and two gunners aboard the Caledonia (Master Ragnvald Andresen) died in the engine room. Five others jumped overboard and tried to get to the only launched lifeboat, but they drifted into the burning inferno around the nearby torpedoed Oilfield and died. The 25 men in the lifeboat desperately tried to rescue them, but this had to be given up because of the intense heat. The survivors were picked up by the British rescue ship Zaafaran and landed in Gourock on 1 May.