On the 15th of July U-135 had been to forced to remain submerged all day due to the presence of enemy aircraft. When it surfaced it found itself in the midst of the convoy. It made its attack and immediately submerged again. the torpedo was seen intermittently breaking the surface as it passed between columns 10 and 11 of the convoy and finally struck HMS TWICKENHAM on the starboard side forward.
13 minutes later, HMS MIGONETTE gained contact and began an attack with the aid of HMS ROCHESTER and HMS BALSOM. When the counter attack began, U-135 was at 620 feet so it went deeper to 850 feet and then tried to surface as the attack had been particularly damaging. It succeeded in getting to 620 feet and then sank again to 720 feet. The attempt to surface was repeated with the same results, and on the third attempt, when the boat was at 230 feet coming to the surface, the last of 70 depth charges dropped during the attack exploded very close aboard.
The submarine then succeeded in coming to the surface at a steep angle and the Commanding Officer immediately jumped overboard without a life jacket, but attempted to steal one from one of his petty officers who was in the water nearby.
As soon as the submarine broke surface an American PBY Catalina flying boat which was over the scene, carried out a bombing attack and the submarine, although being abandoned, began steaming in circles as HMS MIGNONETTE prepared to ram her. This succeeded and the submarine sank. There were 42 survivors.
The captain at the time of U-135’s sinking was Chief Lieutenant Otto Luther. Captain-Lieutenant Friedrich Hermann Praetorius survived the war working as a captain on several German merchant ships. He died on April 16, 1956 in Lubeck. He was 52 years old.
U-135 did not report the sinking of the Gandia until a few days later. According to the war diary of the German Commander in Chief for Submarines, U135 reported on January 26th that it had ‘…sunk a 5000 ton freighter in BC9167 on 22nd January’.
The crew of the submarine would have to estimate the tonnage of their target from a distance in very rough conditions, perhaps this explains the slight errors in the Gandia’s size and position.
The following is an extract from a magazine published in Germany after the war. Mr Hubert was the Second Officer on board the ‘Gandia’, and was in charge of boat 4:
Upon composing this issue, Mr. Albert Hubert announced to us that after the war, they found in the archives of the “Wartime Marine” the following statement concerning the torpedoing of the Gandia’ :
“The convoy had the registration number 0N56. The Gandia was torpedoed on the 22nd of January 1942 at 22:21 hours, German time, in position Latitude 42.45 N – Longitude 53.00 W in the Kriegsmarine map square BC 9159, by a German submarine, the U- 135, in command of Captain-Lieutenant Friedrich Hermann Praetorius.
This U-boat was subsequently torpedoed on the 15th of July 1943, between Cape Juby and the Canary Islands , by three ships cooperating together, the British sloop HMS Rochester and the British corvettes HMS Mignonette and HMS Balsam”