At 22.36 hours on 5 Februar 1942 U-136 fired a spread of three torpedoes at HMS Arbutus (K 86) (T/Lt A.L.W. Warren, DSC, RNR), which was escorting convoy ON-63 about 340 miles west-northwest of Erris Head, Ireland. The corvette was hit on the starboard side abreast the forward bulkhead of No. 1 boiler by one torpedo and sank immediately after breaking in two. The commander, three officers and 38 ratings were lost. 33 survivors were picked up by HMS Chelsea (I 35) (LtCdr A.F.C. Layard, RN) within two hours after the attack. Nine of them were in critical condition and one of whom succumbed during the night. The destroyer immediately proceeded to Londonderry to land the injured men there on 7 February and then landed the remaining survivors at Liverpool on 9 February.