Royal Navy anti U-boat tactics were being continuously developed. There was now much better co-ordination of the convoy escorts who worked together in persistently hunting down U-boats when they were located. Most importantly there were many more aircraft being employed with convoys, now that the ‘Escort carriers’ were taking over from the Hurricats. Inexperienced U-boat commanders now found the odds stacked against them:
According to prisoners’ accounts of operations up to this time “U 131” had been proceeding submerged since the break of day, but had surfaced for a quick look around at the very moment when a British aircraft was within visual range. This was at 0925. Baumann deduced correctly that the aircraft would draw British warships to his position, if he had been sighted, and he dived to 250 ft., after, it was stated, he had sighted approaching warships.
At 1108, as one prisoner stated, a number of depth charges exploded around the U-Boat. Three were particularly close and damage within the U-Boat was severe. A considerable quantity of water entered aft and, according to one prisoner, the U-Boat lay at an angle of nearly 40° and began to sink. A number of gauges in the control room were smashed and the electric motors damaged, although they did not become entirely useless. Oil from a leaking tank began to pour into the Diesel room. The hydrophones, which had been working at irregular intervals only, now went completely dead. The lights were not extinguished.
Prisoners alleged that “U 131” had sunk to a depth of over 600 ft. before she could be got under control. This statement must be taken with reserve; survivors are always inclined to exaggerate the depth to which they sink during attack. Steel plates were cracking, as if they would give way at any moment. Paint was peeling in blisters from the inside of the hull; locker doors were warped and jammed shut by the tremendous pressure. When all seemed lost Baumann managed to get some trim on the U-Boat and he ordered the tanks to be blown. “U 131” reached surface with only eight kilograms (17.5 lb.) of air pressure left.
Prisoners were of the opinion that, had they been able to remain a further half an hour submerged, they would certainly have escaped. As it was, they broke surface when “Stanley” was still near enough to sight them and she immediately reported to “Stork”; “Submarine on the surface bearing 060°.” “Stork” altered course by Blue Pendant to 060° and ordered ships to proceed at utmost speed. In the ensuing rush the two Hunt class destroyers drew ahead, followed by “Stanley,” then “Stork,” with “Pentstemon” only just astern.
At 1307 “Audacity’s” relief fighter, to whom the U-Boat’s position had been given, dived to attack the U-Boat.
“U 131,” unable to submerge again, had been straining her engines beyond all safety limits to produce her maximum possible surface speed, which prisoners alleged was over 20 knots. She was steering away from the distant destroyers and had hoped to escape out of sight without being seen. She saw the aircraft coming and manned her 2 cm. and 3.7 cm. guns. According to prisoners, they got the range of the aircraft and bullets from the 2 cm. gun struck the cockpit, probably killing the pilot. At the same moment a 3.7 cm. shell scored a direct hit and tore off one wing. The aircraft plunged into the sea.
The renewed lease of life which “U 131” had brought for herself by this success was short. Her best speed, even if she could maintain it, was not enough to out distance the destroyers and, at seven miles range, “Exmoor,” “Blankney” and “Stanley” opened fire, the former making particularly excellent shooting. “Stork” opened fire about five minutes later.
Baumann now recognized that his position was hopeless. His one effective gun at such range was trained forward and could not be brought to bear without a disastrous alteration of course. Accordingly, he ordered a signal to be sent to Vice-Admiral U-Boats, reporting the circumstances.
By this time shells were straddling “U 131” and Baumann therefore ordered the vents to be opened and the crew to abandon ship. When interrogated, Baumann stated that his ship was not actually struck by shells and that she was sunk by scuttling and not by explosive charges. All prisoners stated that although the shooting was very good, “U 131” was not hit.
“Stork” reported that “U 131” fired a few rounds at “Blankney” (a fact not confirmed by prisoners), but sank at 1330 on 17th December, 1941, in position 34° 30′ N. and 13° 45′ W. “U 131’s” entire crew was picked up.
The body of the British pilot was recovered by “Stork” and buried at sea the following day.
For the full report see U-Boat Archive.