WE MUST NOW RETURN to Home waters to assess the change in the maritime situation caused by the fall of France and the loss of Norway, Denmark, Belgium and Holland to Germany. Undoubtedly the most important feature was that the coast of France changed sides. This was more important than the loss of Norway and gave direct access for Germany to the oceans of the world. It gave them naval bases from which their surface warships and commerce raiders could sortie and it gave them U-boat bases which would substantially cut down their passage time to their operating areas and virtually increase their numbers by a third. Furthermore their U-boats would not have to run the gauntlet of our forces in the North Sea and in the Iceland-Faeroes gaps. Blockade-runners also had a much better chance to reach the open sea and return than before and they too could by-pass the Northern patrol. It also opened an Axis sea route to the Iberian Peninsula and provided another source of iron ore from Spain. Finally it turned the English Channel from an Allied lake into a front line battlefield. It could no longer be used as a major and safe approach route for merchant traffic to south or east coast ports and could not be used as a training and trials area for the Navy.

The measures to prevent the French Fleet falling in to the enemy's hands worked more satisfactorily in the Channel and on the Atlantic coast of France than they did in the Mediterranean. The nearly completed new battleships Richelieu and Jean Bart were got away to North Africa and the old battleships Courbet and Paris crossed the Channel to British harbours. We have already told how the French submarines, except Rubis, which fought with us in the Norwegian campaign, returned to France in late May and early June. We have also told how the submarine cruiser Surcouf came back with five other French submarines¹.

The first effect of the fall of France upon our submarines in Home waters was that in June all submarine and ant-submarine training had to be moved from the Channel to the west coast of Scotland. Here in July a new Seventh Submarine Flotilla was established at Rothesay based on the depot ship Cyclops under the command of Captain RLM Edwards RN. This flotilla took over all the training submarines formerly based at Portsmouth and Portland.

Anti invasion measures had been given a high priority by the Government and in July, C-in-C Western Approaches asked for submarines to patrol off Brest and the Biscay coast of France to guard against an invasion if it should be launched from that area against the United Kingdom or Eire. C-in-C Portsmouth also asked for submarines to patrol off the French coast in the Channel for the same purpose. VA(S) at once allocated the new submarines Tigris and Talisman, and Cachalot, which had just completed a long refit, to patrol in the Bay of Biscay. These submarines were based in the Clyde and attached to the new Seventh Submarine Flotilla. At first the Fifth Submarine Flotilla at Portsmouth had only L27 and H43 for patrols in the Channel that started in mid August.

On 16th July, Tigris (Lieutenant Commander HFB Bone RN) sailed from the Clyde to patrol off Bordeaux. Her aim was primarily to report any invasion forces sighted and she was only allowed to attack after she had reported them. She was, however, allowed to attack cruisers and above before making a report and other warships if she considered the compromising of her position to be justified. She sighted many French fishing vessels and some French merchant ships but little else. The German U-boats, however, had already started to use French bases, the first, U30, arriving at Lorient on 7th July. Tigris was relieved by Talisman (Lieutenant Commander PS Francis RN) and she landed two agents on 2nd August near Hourtin Lighthouse. She sighted large numbers of fishing vessels too and complained that they interfered with the efficiency of her patrol. On 19th August, Cachalot (Lieutenant Commander JD Luce RN), which followed Talisman laid fifty mines south of Penmarch and then continued her passage towards Bordeaux². Next day she gained a substantial success when she sighted U51 at night inward bound. She fired a full salvo of six torpedoes at a range of 1500 yards, hitting and sinking her. In her second patrol, Tigris was sent to the Isle de Croix area to watch Lorient where the U-boats were based. Here on 1st September she attacked what she thought to be a U-boat at night and sank it with a torpedo at a range of 300 yards. Unfortunately it turned out to be a trawler of 168 tons.

After the Norwegian campaign as we have already noted, the German U-boats had returned to the Atlantic and by now their successes were causing alarm. They sank 267,180 tons of shipping in June alone. C-in-C Western Approaches began to press for more anti U-boat patrols by our submarines, and in this C-in-C Home Fleet backed him. VA(S) was reluctant to use our submarines for this purpose because they had a larger silhouette than the U-boats and he believed them to be at a disadvantage at night. Nevertheless on 23rd August, Tribune (Lieutenant EF Balston RN) from the Second Flotilla at Rosyth was sent to patrol off the Rosemary Bank and Trident (Lieutenant Commander GM Sladen RN) to patrol thirty miles west of St Kilda.

Not very much happened in the northern North Sea during the last part of September and during October. The Netherlands submarines O21, O22, O23 and O24; the French Rubis; the Polish Wilk as well as Sunfish, Snapper and Sturgeon all persevered, generally in very bad weather. Snapper's ninth patrol was in the entrance to the Skagerrak and was blank. She saw only a few aircraft and was then caught in a gale. Rubis also had a blank patrol in September near the Dogger Bank and the weather was very bad. In October she had another blank patrol off Bomalfjord and Stavanger. Rubis was unable to lay mines in these patrols as the stock had run out. She was not really satisfactory for ordinary patrols as her torpedo armament was weak. She had only two bow torpedo tubes and a rotating tube aft⁶. O21 off Skudenes in the German records is said to have just missed U61 with torpedoes but there is no indication in British records that she fired torpedoes at this time. On 13th October, O23 (Luitenant ter zee le KI GBM van Erkel RNN) patrolling the northern entrance to Bergen grounded off Feje when she entered the Fjord; however she got off but found no targets. During October, Wilk (Komandor Podporucznik B Krawczyk) in the Lister area attacked a small steamer on 19th. She fired three torpedoes at 800 yards but she lost trim and missed the director angle. A tube also misfired and she did not obtain a hit. Wilk was, in spite of a refit in Dundee, in poor mechanical condition and her crew were in need of operational training. After two more short patrols in both of which she broke down, she was relegated to reserve and her ship's company used to commission the new British U-class submarine Urchin.⁷ On 29th October, O24 (Luitenant ter zee 2e KI O de Booy RNN) off Kors Fjord, missed a small merchant vessel with two torpedoes at a range of 4000 yards when the enemy took avoiding action. In the Bay during September, Porpoise (Commander PQ Roberts RN) laid 48 mines on 13th south of the Isle d'Yeu and Cachalot (Lieutenant Commander JD Luce RN), 50 mines off Lorient. Both submarines then went on to patrol in the area. These two mine-fields failed to sink any enemy ships.

On 28th September the German heavy cruiser Hipper sailed for St Nazaire where it was intended that she should be based. She broke down off Stavanger and, although radio intelligence gave her away, she got back to Kiel without being seen by any of our submarines. A month later the pocket battleship Scheer, which had been in the dockyard for modernisation since before the war, was now ready for sea. It was planned that she should sail from the Elbe on 23rd October to break out into the Atlantic. The Germans, however, received intelligence, probably through wireless intercepts, that the British knew of the impending sortie. Scheer was therefore held back for several days. The British had indeed some information, but it was of a movement from Norway to Germany. O24 and Seawolf were on patrol off the northern and southern entrances to Bergen and were to move to intercepting positions eighteen miles off the coast on 24th October. Scheer went east to Gdynia and then on 27th October returned through the Kiel Canal and broke out passing east of the declared area anchoring briefly at Stavanger on 28th October. She then made a passage inshore up the coast of Norway leaving it in latitude 63 N and passing in very bad weather out into the Atlantic by the Denmark Strait. O24 and Seawolf had by this time left their intercepting positions, which were in any case too far out, and although ordered to return to them were too late. However she must have passed quite close to Sturgeon during the night of 27th/28th October. Sturgeon (Lieutenant GDA Gregory DSO RN) had left Blyth to make the first of the occasional patrols in the Skagerrak. Off Obrestadt she sighted a number of ships and on the 3rd November, she fired three torpedoes at a range of 4000 yards at a small merchant ship off Oslo Fjord and missed. A quarter of an hour later she fired another three torpedoes at a merchant ship of 1331 tons, also at 4000 yards, obtaining one hit and sinking her. She then withdrew along the coast and next day she missed the 1200-ton Uly with two torpedoes at 1000 yards off the Lister Light. She continued to withdraw along the coast and on 6th November off Egersund, she fired another two torpedoes at a range of 1000 yards at the 1300-ton Delfinas hitting and sinking her with one of them. Sturgeon returned to Blyth on 8th November with only two torpedoes left and with valuable information about what was going on in the Skagerrak. Rubis (Capitaine de Corvette G Cabanier) was out again too, and on 3rd November, she landed an agent near Nappen. She then patrolled off Kors Fjord in very bad weather. Rubis had another blank patrol off Utvaer in December and then went into a refit in Dundee in which her mining tubes were to be modified to take the Vickers T3 mine. On 5th November O22 left Dundee to patrol off the Lister Light. Signals were sent telling her to patrol off the Naze, but it is now fairly certain that she struck a mine and was sunk on her passage out as she passed north of the German declared area. She was lost with all hands including her Commanding Officer, Luitenant ter zee 1e KI JW Ort RNN and the British Liaison Officer and two communication ratings. At the time the cause of her loss was uncertain⁸ and it was thought prudent to cancel a second foray into the Skagerrak by O24. On 25th November the Sealion (Lieutenant Commander B Bryant DSC RN), on patrol off the Norwegian coast fired two torpedoes at a range of 4000 yards in very rough weather at a large tanker. The ship was difficult to see and she altered course away during the attack and the torpedoes missed.

Further south, anti-invasion patrols were continued during September and October by training submarines of the H-class based ashore at Harwich. Their principal duty was still reconnaissance and attack should any invasion force sortie. There were plenty of tugs and barges assembled in the Dutch estuaries and harbours and up to mid September the Germans definitely planned to use them⁹. On occasion these submarines were able to interfere with the enemy coastal traffic, some of which was involved with preparations for an invasion. On 16th September, H49 (Lieutenant MA Langley RN) made a night attack on a large convoy in bright moonlight. She fired four torpedoes at 1400 yards range from the surface and then dived. She heard two hits and according to German recordssank a ship of 2186 tons. On 22nd September, H44 (Lieutenant JS Huddart RN) fired one torpedo in a submerged attack on a merchant ship but missed. She lost trim when firing and a second torpedo was not fired because by then she had a large bow down angle. On 1st October, H49 again attacked a convoy of six merchant ships at night firing four torpedoes at 4800 yards but at this long range, she missed. Finally on 11th October in a submerged attack, H28 (Lieutenant EA Woodward RN) fired two torpedoes at a small merchant ship at a range of 3000 yards but also missed. On 18th October, the enemy anti-submarine vessels UJ116 and UJ118 assisted by aircraft sank H49 and the Germans took one rating prisoner. The rest of the ship's company were lost including her Commanding Officer, Lieutenant RE Coltart DSC RN, three other officers and twenty-two men. It appears that H49 surfaced in poor visibility close to where the German ships lay stopped and in contact, and they sank her. By the end of October the threat of invasion had receded sufficiently to withdraw these patrols and to close the base at Harwich. The submarines were in any case urgently required for antisubmarine training for the forces defending our trade in the Battle of the Atlantic. Although the training submarines conducted attacks in this period, this was not really what they were on patrol to do. As our outer line of defence against invasion they were indispensable and while doing this duty they provided excellent operational training for their ship's companies who were destined to man the new submarines which were building.

It may seem a reflection on the training and efficiency of British submarines that all these attacks on U-boats missed. U-boats were, however, difficult targets. Three of the attacks were on submerged U-boats using asdic and the chance of success was very small. As has been pointed out before, there was no way to find the depth of the target and it was difficult, with step-by-step transmissions across the target, to aim the torpedoes accurately. Two more were at very long range with small chance to hit. Three were at night when our submarines, with their larger silhouettes, were at a disadvantage. For some reason, in the three day-attacks at reasonable range, full salvoes of torpedoes were not fired and this may have contributed to their failure. Post war German records reveal that during September and October sixty six movements of U-boats took place in and out of their bases, so that our submarines intercepted about 17% of them.

Meanwhile on 5th November, Scheer intercepted the Halifax convoy HX84 and sank its escort, the armed merchant cruiser Jervis Bay and five other ships. The Admiralty believed that Scheer would either return to Germany or to a French Biscay port and, among many other dispositions, submarines were placed to intercept her. Orders were sent to O22, Sturgeon and Rubis, who were already out, to patrol eighteen miles off the Norwegian coast. In the Bay, Usk, a brand new U-class submarine on passage from the Clyde to Portsmouth, was ordered to patrol off Brest while Trident, already on patrol, covered the entrance to St Nazaire and Tuna, also on patrol, guarded the Gironde. Scheer however continued her cruise in the Atlantic and normal patrols were resumed on 9th November. The Admiralty were understandably worried by Scheer's attack on HX84 and raised again the question of using submarines to escort Atlantic convoys. VA(S) was still opposed to submarines being used in this way. This was especially so as the Netherlands submarine O14 had just had a difficult time when crossing the Atlantic with HX79 which lost twelve ships to a pack attack by U-boats. He compromised, however, by suggesting that a submarine should be based on Halifax to escort convoys in the western part of their passage across the Atlantic where there were no U-boats operating and should return to Halifax before entering the area where U-boat attack was likely. The Admiralty agreed and on 18th November Porpoise was withdrawn from a patrol in the Bay of Biscay for this purpose and sailed for Canada on 30th. She was followed by Severn who had just completed a refit and she sailed on 9th January.

After anti invasion patrols in the Channel and southern North Sea had been discontinued at the end of October, submarines still found plenty to do in the Bay of Biscay and off the Norwegian coast. Although invasion was now considered unlikely if not impracticable for the rest of the winter, precautions were not relaxed entirely. Submarines, however, were used mainly for anti U-boat patrols and, when necessary, for operations against the German heavy units. They also kept up pressure on the enemy coastal traffic and did their best to prevent blockade running. It had now been decided that in addition to the four T-class that had already reinforced the Mediterranean, all new construction submarines should go there too. This included the remaining T-class of the pre-war construction programmes and the first twelve U-class ordered at the outbreak of war. The first six of the U-class had either been delivered or were nearing completion. The new U-class were originally to have been used in the North Sea based at Blyth but were diverted to the Mediterranean to answer C-in-C's call for smaller submarines.

In the last part of the year, submarine patrols in the Bay of Biscay, as well as watching for U-boats and German heavy units, began to be more active against coastal traffic and blockade-runners. On the 30th October the armed merchant raider Widder had returned to Brest after her first cruise without being seen. On 2nd November, Taku (Lieutenant JFB Brown RN) in a night attack fired eight torpedoes at a range of 800 yards at the inward bound tanker Gedania of 8923 tons west of the Isle d'Yeu and sank her. On 13th November, Tigris (Lieutenant Commander HF Bone RN) sank the barque Charles Edward of 301 tons by gunfire sixty miles west of the Gironde, missing with two torpedoes in the process. Both were fired at close range, one ran under and the other exploded short of the target. On 25th November off St Nazaire, Talisman (Lieutenant Commander PS Francis RN) fired six torpedoes in a day-submerged attack at a range of 6000 yards at a tanker escorted by three trawlers without success. One torpedo dived to the bottom and exploded and the others missed. Two more torpedoes slid out of their tubes as a result of the explosion and were lost. Talisman had been instructed to try and capture a tunny fisher of which there were many in the area, so that it could be used to land agents and. possibly to monitor U-boat movements. On 27th November she took Le Clipper of 40 tons and sent her into Plymouth. Much useful intelligence was obtained from her crew. On 30th November the blockade-runner Helgoland arrived at St Nazaire from Colombia. There were two submarines in the Bay at the time, Talisman off Lorient and Taku off the Gironde, but they did not see anything. On 15th December, Thunderbolt (Lieutenant Commander CB Crouch RN) off the Gironde fired six torpedoes in a day-submerged attack at a range of 4000 yards at the Italian submarine Tarantini escorted by three trawlers and sank her. She was counter attacked with depth charges but was undamaged. The next day Tribune (Lieutenant EF Balston RN) fired six torpedoes at a range of 4500 yards at a tanker escorted by two trawlers off the coast near the Isle d'Yeu. In spite of one torpedo diving to the bottom and exploding, she obtained one hit. The enemy, however, did not sink and was only damaged. The two trawlers counter attacked dropping thirty depth charges but Tribune emerged unscathed. On 18th December, Thunderbolt was detected and attacked close off the mouth of the Gironde by a sloop using an explosive sweep that went off when it snagged the submarine's jumping wire but fortunately did no damage. On the same day, Tuna (Lieutenant Commander MK Cavanagh- Mainwaring RN) in the early morning missed a U-boat off the Gironde. The range was 1500 yards and she fired six torpedoes but the enemy must have seen the tracks as she altered away and they missed. She then engaged with her gun claiming one hit. She also fired two more single torpedoes after the enemy who fired a torpedo back but there were no hits. Later the same day after dark, Tuna encountered the armed tug Ita and fired two torpedoes, one of which had a gyro failure and the other missed. She then sank the tug by gunfire. Finally Tribune in a day submerged attack fired six torpedoes at very long range (7500 'yards) at a large merchant ship escorted by a destroyer well out to sea off Lorient but failed to secure a hit.

This period of five months in the late summer, autumn and early winter of 1940, was a busy one for our submarines in Home waters. Their area of operations was greatly extended taking in the Dutch coast, Channel and Bay of Biscay as well as the North Sea, Norwegian coast and the Skagerrak. As we have seen they were employed for many purposes, the principal ones being anti invasion and anti U-boat patrols. They were also used in operations against the German heavy ships and armed merchant raiders as well as their blockade-runners. Almost as a sideline they also struck at the enemy coastal traffic whenever possible. Finally they were used to try and prevent the enemy occupying the Azores and at the very end of the period one submarine was diverted to escort convoys. The number of submarines was thirty-nine in early September but dwindled to twenty-two at the end of the period as the training submarines went back to their proper duties. Operations were, with the longer nights and the patrol areas in more open waters, less hazardous and our casualties were kept down to three boats. O22 and Swordfish were lost to mines and H49 to enemy air and surface antisubmarine craft. Against these losses, two U-boats were sunk as well as seven merchant ships of 30,124 tons, an anti-submarine trawler and an armed tug. These results involved a total of forty-three attacks and the expenditure of 174 torpedoes. Five torpedoes failed to run due to misfires or drill failures and nine malfunctioned after firing either diving straight to the bottom, exploding prematurely or suffering a gyro failure.

Medals for this period in Home waters were distributed, considering the results, fairly generously. No less than six Distinguished Service Orders were awarded as well as four Distinguished Service Crosses to Commanding Officers and also a Mention in Despatches. The DSOs went to Lieutenant Commanders Luce and Crouch of Cachalot and Thunderbolt for sinking the U-boats Usi and Tarantini. They also went to Lieutenant Commanders Bone and Cavenagh-Mainwaring of Tigris and Tuna and to Lieutenants Balston and Cowell of Tribune and Swordfish for their 'good services in recent patrols'. The DSCs went to Lieutenant Commander Sladen of Trident for damaging U31 and to Lieutenants Campbell and Langley of L27 and H49 for attacks on enemy supply vessels. Lastly the Mention in Despatches was for Lieutenant Commander Haggard of Truant for intercepting the Tropic Sea.

Losses of Allied submarines had been very heavy in 1940. During the year in all areas including the Mediterranean, twenty-six British submarines had been lost and strength fell to a total of forty-four boats. However the twelve U-class ordered at the outbreak of war were now coming into service and we had been joined by eleven boats of the Royal Netherlands Navy and four from France¹⁶.The greatest loss was in experienced submarine personnel and practically all of the lost crews were long service peacetime trained officers and men. They had not been diluted with newly trained men before being lost and it was going to be difficult to find enough experienced men to form the nucleus of the crews for the large number of new submarines building. For instance, a number of submarines had been lost with three and even four regular officers in their crews who would have been due to qualify as Commanding Officers within the next year or so.

At the outbreak of war after the completion of mobilisation, 3383 ratings were available to man our submarines. Of these 474 were of the Royal Fleet Reserve, that is former submarine ratings who had returned to civilian life. The great majority of officers and men serving in submarines were volunteers, only 108 of the total being 'pressed men'. After a year, that is on 3rd September 1940, the total had fallen to 3227 and 545 men had been killed in action and 115 taken prisoner of war. Up to the end of 1940, 1425 new ratings had been trained in submarines. These were nearly all long service men but included a few 'hostilities only' ratings enlisted for the duration of the war¹⁷.

It has already been noted that the Admiralty had decided to send all new construction submarines to the Mediterranean. Although no formal strategic decision in this matter was taken, there is no doubt that from the end of 1940, the Mediterranean became the most important station for submarines and the scale of operations at home declined. It is to the Mediterranean that we must now return to see how this came about.