U-boats U73, U69, U96, U107, U552, U97 and two Italian boats, Barbarigo and Bianchi, had lost contact on the evening of the 22nd, and had set up a new patrol line ahead of the convoys most likely course. During the 23rd, the U96, U69 and U107 had reacquired contact with the convoy, which had turned north to try and avoid this new patrol line, and now they started to close in.
On the night of 23-24 February, as the convoy had reached its dispersal point and they all took course for their various destinations, a pack of 6 boats, U69, U73, U95, U96, U107 and Bianchi fell upon the unescorted merchantmen.
U96, (Kapitanleutnant Heinrich Lehmann-Willenbrock) first sighted the Sirikishna at 23.46 hrs on the 23rd, when she was steaming at 9 knots on a north westerly heading. At 00.20 hrs on the morning of the 24th, U96 ran into the attack and fired one torpedo which struck the Sirikishna on her port side amidships, whereupon she stopped and blew off steam, and her master ordered the crew to abandon ship.

Although taking a list, the Sirikishna was still afloat over an hour later, so Kapitanleutnant Lehmann-Willenbrock decided to launch another attack. However, U96 had to strike down another torpedo from the upper deck since all those stowed below had been expended. This operation took quite some time, and it was not until 06.36 hrs that the second torpedo was fired, which hit the starboard side amidships, whereupon she broke in two, and sank in approximate position 59°N, 21°W.

Apparently none of the crew survived, even though they had managed to get away in the lifeboats.
There are three differing versions of what occurred that night. Chronology of the War at Sea states that she was sunk by one torpedo and gunfire, and Jurgen Rowher only mentions the latter attack with one torpedo. The above account is from the war log of U96, and is, in my opinion, the correct version of that tragic night from the only people alive to retell the event.
In all, OB288 lost 10 ships sunk by U-boats and 2 damaged by aircraft out of the 42 ships that had started out, yet very little is heard about this convoy, or any of the others that were badly mauled by wolf packs at this stage of the war. Official sources list these ships as sunk after the convoy had dispersed, so they were classed as independents and not under the protection of the Royal Navy. No ships were lost from this convoy whilst it was under Royal Navy escort, so the public could be assured that ships protected by the Royal Navy were safe on the high seas, and Britain still ruled the waves.
Three quarters of the crew were family men, and nearly half of these left their families with a debt to the ship owners, as all wages were stopped the day the ship was lost.
After the attack on OB288, U-96 was depth charged for nearly 12 hours, but does anybody know who the escorts were that carried this out.