Convoy TM 1

Convoy TM 1 was the code name for an Allied convoy during the Second World War. Nine tankers, escorted by Royal Navy warships, attempted to reach Gibraltar from Trinidad. The convoy was attacked by a U-boat wolf pack (Delphin) in the central Atlantic Ocean and seven of the nine tankers were sunk. This was one of the most successful attacks on Allied supply convoys of war.^[1] The convoy was defended by the destroyer HMS Havelock and three Flower-class corvettes, HMS Godetia, Pimpernel and Saxifrage. The two surviving tankers reached Gibraltar.^[2] Two U-boats were damaged during the attacks.

In 1942 1,664 Allied ships of 7,790,697 GRT had been sunk, 1,160 of the ships (6,266,215 GRT) by U-boats. Imports into Britain had been reduced by a third of the peacetime rate to 34,000,000 long tons (35,000,000 t) a year. The Prime Minister, Winston Churchill, formed and chaired a cabinet Anti-U-boat Warfare Committee on 4 November. By the end of the year there were only 300,000 long tons (300,000 t) of bunker fuel in Britain with monthly consumption at 130,000 long tons (130,000 t). The Admiralty had a reserve of 1,000,000 long tons (1,000,000 t) but this was for emergencies.^[3]

The unexpected delay in the capture of Tunisia after Operation Torch added to the drain on British fuel stocks as despatches of petroleum products to Tunisia for British forces in the theatre came from Britain. The need to begin convoys in US waters caused delays to taker sailings across the Atlantic and between 1 January and 31 December 1942, 218 tankers were sunk. Exceptionally stormy weather during the autumn and winter of 1942 was particularly damaging to tankers and by the end of the year, 1,700,000 DWT (25 per cent) of the British tanker fleet of 7,600,000 DWT was being repaired or out of service.^[4]

Churchill was told by Admiral Sir Dudley Pound, the First Sea Lord, that "An ample reserve of fuel on this side of the Atlantic is the basis of all our activities". The convoy cycle in the Atlantic was lengthened from eight to ten days and the saving in escorts was diverted to the Caribbean to escort 18 CU–UC tanker convoys from Aruba to Britain on a twenty-day cycle, to deliver1,200,000 long tons (1,200,000 t) of petrol products in 1943. A new convoy route direct to the Mediterranean (OT–TO) was organised to limit the drain on stocks of oil in Britain. The OY–TO convoys were to consist only of "Greyhounds" capable of at least 14.5 kn (26.9 km/h; 16.7 mph) and be escorted by modern USN destroyers; other Greyhounds were to sail independently to Britain.^[5]

German Type IX and Type VIID minelayers, U-boats operating in American waters had sufficient endurance but were not suitable for convoy attacks or crash-diving. Admiral Karl Dönitz the Befehlshaber der U-Boote (BdU, commander of U-boats) sent six Type VII U-boats to patrol off Natal in Brazil to attack the new convoy routes. The boats sailed from 17 to 22 December as Wolfpack (gruppe) Delphin to rendezvous with U-463 a Milchkuh supply submarine. B-Dienst, the code-breaking branch of the German Naval Intelligence Service notified Dönitz of a new UGS convoy route to the south of the Azores and gruppe Delphin was diverted to search to the south-west of the Azores. The search found nothing and on 2 January the boats were ordered to refuel from U-463 and resume the voyage to Natal.^[6]

Escort Group B5 (Commander Richard Boyle) had been on detachment to the Caribbean for six months and consisted of the H-class destroyer HMS Havelock and the Flower-class corvettes HMS Godetia, Pimpernel and Saxifrage. The US Eastern Sea Frontier commander had asked for the ships to be painted grey and there was no time to re-paint the ships in Western Approaches Command camouflage. Havelock and Saxifrage carried high-frequency direction finding apparatus (Huff-Duff) but the set on Havelock was unserviceable. The radar on Godetia failed on 2 January 1943 and after 8 January the set on Pimpernel lost efficiency.^[7]

The convoy sailed from Port of Spain, Trinidad on 28 December for Gibraltar but without Godetia that was escorting two tankers that were catching up with the convoy.^[a] The convoy was escorted by a Catalina flying boat and early on 29 December, the crew reported a surfaced U-boat (U-124) about 20 nmi (37 km; 23 mi) behind the convoy. The Catalina attacked the U-boat with depth-charges and mousetrap bombs, forcing it to dive and Godetia conducted a search as it closed on the convoy, to no avail. The tankers were fast but eking out the fuel of the corvettes in the escort limited its speed to around 8 kn (15 km/h; 9.2 mph), reduced further by headwinds and a contrary ocean current.^[9]

Attempts to refuel by the escorts were hampered by lack of training and poor equipment but Cliona managed to pass some fuel across to the escorts. After the first U-boat sighting, all was quiet for three days; during the afternoon of 3 January, when Convoy TM 1 was about 1,050 nmi (1,940 km; 1,210 mi) east of Trinidad, the convoy received a signal from the Admiralty that another U-boat was nearby and later on, the US Eastern Sea Frontier commander ordered a course change to just north of east. As night fell, a U-boat was spotted at long range and at 9:35 p.m. Havelock received an Asdic contact 3 mi (4.8 km) in front of the convoy.^[9]

On 3 January, having received an Asdic contact, Havelock accelerated towards a U-boat but then another one was detected by radar. At 9:46 p.m. the officer of the watch in British Vigilance spotted the outline of a U-boat ahead and then a torpedo hit the ship and its cargo of 11,000 long tons (11,000 t) of petroleum caught fire, illuminating U-514 as it passed the ship down its port side. Every gun in the tankers that could bear opened fire on the U-boat, Empire Lytton, the second ship in the third column, tried to ram U-514 and claimed around 200 hits with its two 20 mm Oerlikon guns at 200–300 yd (180–270 m) before the U-boat went out of sight; the crew of the 4-inch gun on Oltenia II claimed a near-miss.^[10]

Boyle ordered a Raspberry manoeuvre but only Pimpernel sighted anything, a disturbance in the water on the starboard side of the convoy that might have been from a submerging U-boat. Captain Evan Evans, the skipper of British Vigilance ordered abandon ship, he and 26 survivors went over the side and were picked up by Saxifrage. The other 27 crew were left on the wreck that drifted behind the convoy and burned out; three weeks later the hulk was sunk by U-105. The Huff-Duff set on Havelock was repaired and the escorts managed to take on fuel on 5 January, enabling several offensive sweeps but nothing was found until late evening of 8 January.^[10]

U-381 made contact with the convoy on 8 January and the five other U-boats of gruppe Delphin closed on the convoy. Dönitz diverted U-511 and U-522, outbound type IX boats of gruppe Seehund. U-128 and U-134 returning from patrols the South Atlantic and U-181 a long-range Type IXD2 submarine returning from the Indian Ocean. The orders from Dönitz sent five Type IX, seven Type VII and a U-cruiser into the attack on the convoy but U-125, U-128 and U-514 were too far from the convoy to catch up.^[11] At 9:35 p.m. Havelock was ahead of the convoy, to port and obtained a radar contact between it and the convoy. Havelock attacked at full speed, spotted a U-boat on the surface and attempted to ram but the U-boat submerged. An Asdic contact was picked up and five depth-charges were dropped. Explosions occurred in the convoy as Albert L. Ellsworth in position 1:1 and Oltenia II in position 6:1 were hit by torpedoes from U-436 of gruppe Delphin.^[2] Havelock damaged and drove off U-381, while Pimpernel and Godetia drove off U-571 and U-575 respectively.^[12] U-522 returned the following morning and damaged two tankers, Norvik and Minister Wedel, while U-442 damaged Empire Lytton. U-181 and U-134 attacked, but failed to hit any targets. Godetia damaged U-134 with depth charges.^[2]

U-620 kept in contact with the convoy and on the evening of 9 January, U-522 attacked Norvik and Minister Wedel, the tankers she had damaged earlier in the morning and sank both. U-442 returned to the damaged and drifting Empire Lytton, finishing her off with two torpedoes, while U-436 returned to the abandoned Albert L. Ellsworth and sank her with shells from her deck gun. U-511 came across William Wilberforce, a merchant ship sailing independently and sank her.^[2]

The attacks resumed on the night of 10/11 January, with U-522 torpedoing British Dominion. Her crew abandoned her but the ship did not sink until U-620 arrived and sank her with a torpedo and gunfire. Other attacks that evening and over the next two days, by U-571 and U-511, failed. The convoy was approaching Gibraltar and the destroyer HMAS Quiberon and the corvettes HMS Samphire and HMS Pentstemon were sent out to reinforce the escorts. Supported by Allied air cover, the convoy reached Gibraltar without further loss on 14 January. Cliona and Vanja, survived from the original nine. The final action came on 24 January, when the abandoned hulk of British Vigilance, torpedoed by U-514 on 3 January, was discovered by U-105 and sunk.^[13]

Clay Blair wrote in 2000 that it was hard for the BdU to assess the result of the operation against Convoy TM 1 but the U-boats had claimed hits on 25 ships, 15 having been sunk. Despite obvious over-claiming when U-boats had fired at the same ships Dönitz allowed the claims. Admiral [[[Erich Raeder]] sent congratulations to Dönitz and the crews of gruppe Delphin. The propaganda machine claimed 15 ships of 142,000 long tons (144,000 t) against seven tankers of nine being sunk for 56,453 long tons (57,359 t) that with the addition of William Wilberforce came to 61,457 long tons (62,443 t). The attack on Convoy TM 1 led to substantial changes in the December U-boat deployment plan. None of the U-boats intended for the Americas arrived; the patrol of gruppe Delphin to Natal was cancelled along with two U-boats intended for the West Indies. U-511 and U-522 had fired so many torpedoes and used so much fuel that they could not operate with gruppe Seehund due for Cape Town and the Indian Ocean. Gruppe Delphin with the four Type IX boats that had participated, U-125, U-511, U-514 and U-522 and five Type VII U-boats that sailed in January stayed near the Azores, taking the place of the defunct gruppe Westwall.^[14]

In 2004, Richard Woodman wrote that the conduct of Convoy TM 1 had been a disaster. The Germans thought that they inflicted fewer losses than was the case, claiming 15 tankers. In 1989 G. Hessler wrote that "The convoy escort...was unpractised and lacked perseverance".^[15] At the same time,

Preoccupation with torpedoes tankers and enemy depth-charge attacks soon caused many...to drop astern, so that after the second day only four boats were still in touch, and the pursuit was abandoned on the [sic] 11 January near Madeira.^[15]

The four drifting wrecks were sunk but none of the U-boats that sank tankers lasted long and this has been used to criticise Boyle and his escorts but this did not take account of the weakness of the escort and the trouble that RN crews were still having in refuelling at sea.^[15]

The Admiralty put Captain W. G. Parry of HMS Renown in charge of an inquiry. The inquiry considered whether the tanker Vanja that had allegedly given cause for suspicion with poor station-keeping and for being distant from ships that were torpedoed. The wireless operator in British Dominion claimed that he had heard homing signals on 500 kcs supposedly from Vanja and an officer on Narvik mentioned a rumour that his wireless operator had also heard the signals. The implications for the crew of Norwegian emigrés but the suspicions were confounded by the captain of Cliona who explained that Vanja was suffering from engine-trouble due to a cracked cylinder. Also considered was allegations of indiscipline on Empire Lytton, whose captain, Andrews, said that "he had never sailed with such a bad crew. Their behaviour when torpedoed was disgusting...". The Ministry of War Transport crewing vessels from a common pool, denying captains a choice of men, was blamed. Parry concluded that Vanja had trouble station-keeping because of the engine-trouble and that the insubordinate crew of Empire Lytton could not be blamed on the captain and officers. The inquiry blamed the inadequate number of escorts, made worse by the radar sets failing in Godetia and Pimpernel.^[16]

• Darman, Peter (2007). A Day-By-Day History: World War II. New York: Barnes & Noble. ISBN 978-1-84999-045-5.

• U-boat.net