Convoy HG 76

HMS Audacity

Audacity participated in the escort of convoy OG 76 of twenty merchant ships, which sailed from Liverpool for Gibraltar on 31 October. The escort carrier embarked 802 Naval Air Squadron (802 NAS) of the Fleet Air Arm with eight Martlets and ten pilots. The weather was atrocious and at times pitched the flight deck 65 ft (20 m) and rolled it 16°, with spray sweeping over the deck. Two Martlets took off on patrol and one managed a safe landing but the other touched down when the stern was rising and was thrown overboard, the pilot being rescued just before the Martlet sank.

On 8 November, Kampfgeschwader 40 (KG 40) sent six Focke-Wulf Condor aircraft to locate convoy SL 91, from Freetown in Sierra Leone bound for Liverpool. Near noon, the radar on Audacity detected two of the Condors and a Martlet patrol was sent to intercept. One Condor escaped in cloud but two Martlets caught the second, which shot down one Martlet before the other Martlet shot it down. About three hours later, another Condor was shot down by a head-on attack and a fourth Condor escaped. KG 40 had lost a third of its operational aircraft and failed to direct any U-boats onto either convoy, OG 76 making a safe arrival at Gibraltar late on 11 November. The presence of Audacity was now known to KG 40 and Befehlshaber der U-Boote (BdU, U-boat command headquarters and the title of the commander, Viceadmiral Karl Dönitz).

HG 76

HG 76 (convoy Commodore Vice-Admiral R. Fitzmaurice) comprised 32 ships homeward bound from Gibraltar, many in ballast, or carrying trade goods. The convoy had a strong escort, consisting of 36th Escort Group (Commander F. J. "Johnnie" Walker on his first voyage as commander), usually composed of two Bittern-class sloops (Stork and Deptford) and seven corvettes (Convolvulus, Gardenia, Marigold, Penstemon, Rhodedendron, Samphire and Vetch). This force was augmented by the new escort carrier Audacity, and her three escorting destroyers, Blankney, Stanley and Exmoor, plus the sloops Fowey and Black Swan and the corvettes Carnation and La Malouine; a total of 17 warships.

Seeräuber

Since August 1940, Dönitz had ended the practice of U-boats freelancing and sending only one report per day. U-boat commanders were ordered to signal whenever they found a convoy and shadow it rather than attack. The commander was to send short homing signals every thirty minutes, to guide other U-boats to the convoy. When the pack had assembled, Dönitz gave the order to attack, usually at night, so that the U-boats could fire their torpedoes on the surface. For the tactic to work, U-boats had to signal their positions to Dönitz at Kerneval (across the river from Keroman Submarine Base at Lorient in Brittany). Closer to land, when Condors on Fühlungshalter patrol sighted a convoy, the wireless operator reported its position and course to the BdU and relays of Condors remained over the convoy. When the position of a convoy was established, the information was passed to the senior officer of a group of U-boats organised for pack attacks, who ordered the boat nearest to the convoy to shadow it and guide the rest by wireless. When the pack had rendezvoused near the convoy, surface attacks would be made on successive nights, the U-boats withdrawing during the day. Dönitz assembled wolfpack Seeräuber (Pirate) of six U-boats, (U-67, U-107, U-108, U-131, U-434 and U-574). The pack was reinforced later by three more boats and was given orders to treat Audacity as a prime target.

14–15 December

HG 76 sailed from Gibraltar on 14 December 1941 and was reported almost immediately by German agents across the bay in neutral Spain, who reported the composition, escort strength and departure time of the convoy. HG 76 was also sighted later that day by U-74, en route to the Mediterranean but was lost in poor visibility, while BdU was confused by an agent report that the convoy had returned to port. Fairey Swordfish aircraft of RAF Gibraltar Command (Air Commodore Sturley Simpson) escorted the convoy and on three occasions during the night of 14/15 December, drove off U-boats. The wolf pack formed a patrol line south of Cape St Vincent but HG 76 passed through the line without detection. At 8:15 a.m. Lockheed Hudson and Consolidated Catalina aircraft took over from the Swordfish and for the next two days co-operated with the 802 NAS Martlets on Audacity, forcing U-boats to submerge. U-127 was detected on a routine anti-submarine sweep by a Short Sunderland from Gibraltar late in the day and next morning was detected on Asdic by the Australian destroyer HMAS Nestor and sunk at 11:00 a.m.

16–18 December

On 16 December, HG 76 was sighted and its position reported by a Focke-Wulf Condor patrolling from Bordeaux, which guided U-108 to the convoy to begin reporting its position to other U-boats. During the night of 16/17 December, the wolf pack closed in and by morning on 17 December, the convoy passed beyond the range of Gibraltar-based aircraft and four U-boats made contact. Just after 9:00 a.m. a Martlet from Audacity sighted a surfaced U-boat about 20 nmi (37 km; 23 mi) from the convoy and circled over the area to enable the escort ships to gain a good radar fix and a corvette made an Asdic attack to no apparent effect. At 12:47 p.m. Stanley sighted U-131 (Baumann) on the surface and Walker ordered a Martlet to attack, while Stork, with Penstemon and the three destroyers made their best speed to the location. The Martlet pilot dived towards the U-boat and both opened fire at the same time, the Martlet crashing and the pilot being killed. The British ships opened fire at extreme range and U-131 was driven to the surface and sunk. Observers saw the crew of U-131 abandon the vessel, before it sank at 1:30 p.m. Survivors said that they had been shadowing the convoy (claiming to have spent the previous night inside the convoy, homing other U-boats) and had been the U-boat attacked earlier.

On the night of 17/18 December, the U-boats attacked again but failed to torpedo any ships. At 9:06 a.m. on 18 December, Stanley gained an Asdic contact 6 nmi (11 km; 6.9 mi) and several ships dropped fifty depth-charges. After thirty minutes U-434 (Heyda) surfaced and the crew abandoned ship just before it rolled over and sank north of Madeira, 42 members of the crew being rescued and taken prisoner. Before noon, the radar on Audacity indicated two aircraft and Martlets were scrambled to intercept but the guns on both aircraft jammed and the Condors escaped. The rest of the day was quiet but the Admiralty signalled that three more U-boats were en route and after dusk, a corvette reported a surfaced U-boat. On the night of 18/19 December, Stanley sighted U-574 (Gentelbach) astern at 4:00 a.m., sent a sighting report and was hit by a torpedo and blew up. Stork following behind, swung behind the stern of Stanley, gained an Asdic contact and dropped a pattern of depth-charges, then turned after 0.5 nmi (0.93 km; 0.58 mi) to attack again.

A U-boat shot to the surface 200 yd (180 m) ahead and a chase began; Walker tried to ram the U-boat but found that it could turn inside the turning circle of Stork nearly as fast. The ship fired on the U-boat and illuminated it with snowflakes, managed to ram it just forward of the conning tower and scraped over the hull of the submarine. As the U-boat emerged from under the stern, depth-charges set for shallow were dropped and blew up U-574. The bows of Stork were crushed and bent sideways and the Asdic dome under the hull was smashed. Soon after, U-108 torpedoed the Ruckinge, which was abandoned and sunk later by Samphire. Focke-Wulf Condors arrived, one was shot down in another head-on attack and a second aircraft was damaged. When more Condors reached the convoy in the afternoon, a Martlet pilot made such a determined head-on attack, that he collided with the Condor and came back with its aerial round the tail-wheel; the night of 18/19 December was quiet.

19–21 December

At 7:30 a.m., a Condor appeared to shadow the convoy and a Martlet chased it away before returning for lack of fuel. In the afternoon a Martlet spotted two U-boats and the convoy made an emergency turn. The U-boats were forced to submerge and Martlets patrolled overhead keeping them down until having to return when low on fuel. It was so dark that the aircraft were guided to the flight deck with hand torches and again the night was quiet. On 21 December, 802 NAS could only keep three Martlets operational, take-off and landing was dangerous in the heavy swell and the pilots were very tired. After the last patrol, the comamder of Audacity ordered the ship out of the convoy 10 nmi (19 km; 12 mi) to the starboard as usual but no escorts could be spared. At 8:33 p.m. a ship at the rear of the convoy was torpedoed and nearby ships fired snowflakes, illuminating the area to both sides. Gerhard Bigalk in U-751 saw the silhouette of Audacity at close range and at 8:37 p.m. torpedoed Audacity which began to sink at the stern. Two more torpedoes from U-571 hit the escort carrier, a big explosion blew off the front end and the ship began to sink at the head. Audacity sank head first at 10:10 p.m., 500 nmi (930 km; 580 mi) west of Cape Finisterre.

22–23 December

At 12:40 a.m. on the night of 21/22 December, U-567 (Endrass) was sunk by Deptford, two hours after gaining an Asdic contact. Following this Deptford collided with Stork, damaging them both. During 22 December, U-71 and U-751 remained in contact, to be joined by U-125 (en route to America), while HG 76 was reinforced by the destroyers Vanquisher and Witch. At 10:54 a.m. a Consolidated Liberator of 120 Squadron, 19 Group Coastal Command based at RAF Nutts Corner in Ireland 750 miles (1,210 km) away, arrived over the convoy and saw off a Focke-Wulf Condor. After two hours the Liberator attacked a U-boat and at 4:20 p.m. was relieved by a second Liberator, which forced another three U-boats to submerge. The Liberator turned for home with minimal fuel but next day the convoy came into range of continuous air support. On 23 December, Dönitz, shaken by the loss of five U-boats and the lack of success against the convoy, called off the attack and U-67, U-107, U-108 and U-751 returned to bases in France.

Aftermath

Despite the loss of Audacity and the three other ships, the safe arrival of 30 ships and the destruction of three U-boats (U-127 was not included, and U-567 not confirmed until after the war) was judged to be an outstanding victory. It also confirmed Walker as the Royal Navy’s foremost expert in anti-submarine warfare. The loss of five of the nine U-boats and Endrass, one of the most experienced U-boat commanders, was considered a grievous blow by Dönitz.