WWII – Early Operations: 1939

Fleet Carrier Ark Royal

While Dönitz sought to employ groups of U-boats (wolf packs) against convoys in an effort to overwhelm their escorts by conducting a series of well-coordinated attacks against them (Rudeltaktik), Raeder looked to his capital ships to blow them and the merchant ships they were protecting out of the water. If his naval signals intelligence service the Beobachtungs-Dienst (B-Dienst) could unravel the basic British naval cipher – and it often could – he hoped to be in a position to deploy both U-boats and surface craft to interdict the convoys and savage them. Few in the Admiralty doubted the capacity of the German capital ships to destroy any convoy they fell upon and Churchill, restored at the outset of the war as first lord, was more anxious than most to ensure that these big gun surface ships should be hounded from the oceans of the world before they could do real damage to the British cause in the war. As a result, therefore, whenever the cryptanalysts at Bletchley Park – the Government Code and Cipher School (GC&CS) – could crack any of the German Naval Enigma codes and provide information concerning the movements of these capital ships, Churchill responded by forming groups of warships often backed by aerial assistance to hunt them down. His recurring nightmare was that these armed raiders would break out into the Atlantic and cause havoc on the convoy routes destroying much needed Allied supplies of war materiel. He was determined to prevent this from happening and never wavered from expending much time, effort and money on eliminating this threat whenever and wherever it was formed.

In these early days of the war the difficulty of detection, let alone destruction, of the submarine was experienced by both the surface fleets of the Royal Navy and its German counterpart. Unfortunately for the Admiralty, its confident prediction that Asdic could be relied upon to detect the underwater prowler and neutralise its threat soon proved to be unfounded. Asdic may have been good in ideal circumstances, such as calm seas and not extravagant depths, but its severe technical flaws – both in its limited range and blind spot potential – meant that those vessels equipped with this device would continue to face frustration in trying to find, let alone eliminate, the submarine predator. Only time would reveal the true extent of the problem, but in the meantime the Admiralty, taking its cue from Churchill, sought to grasp the initiative from the U-boats by hunting them down in specially assembled and Asdic-equipped task forces. Much misapplied effort had gone into this pursuit during the First World War, but its lack of success on that occasion did not faze the first lord at all. Once again the new version of the old initiative did not reap the rich rewards that its zealous promoter was looking for and was rapidly abandoned in the light of bitter experience. Three days after the fleet carrier Ark Royal had fortuitously survived a torpedo attack from U39 off the west coast of Scotland on 14 September, another carrier Courageous, working with two destroyers well out to sea off the southwest coast of Ireland, was not so fortunate. She was sunk by U29 at a range of less than 3,000 yards (2743m) with the loss of 514 hands. It was a case of the biter being bitten and Churchill didn’t need any more evidence to suspend the practice: carriers were far too precious to waste in this way.

Ark Royal’s charmed life persisted when she and other units of the Home Fleet were attacked by Junkers-88 and Heinkel 111 bombers as they were going to the aid of the crippled submarine Spearfish in the North Sea on 26 September. Apart from it being the first case of an aerial attack on a fleet at sea, this action also saw the first successful use of radar on board the British battleship Rodney and the light cruiser Sheffield to give early warning of an approaching enemy air strike. Although the Luftwaffe had achieved neither total surprise nor success in this venture they had come perilously close to doing so; registering a near miss against the carrier and hitting the Hood with a bomb that had actually bounced off the battlecruiser and fallen harmlessly into the sea. These initial failures appeared to offer hope for those both on shore and at sea who still clung to the outmoded belief in the primacy of the capital ship over anything that took to the skies. As someone who had consistently supported the Fleet Air Arm in the past, Churchill was far more astute. Despite being the political head of the ‘Senior Service’, he was only too well aware that once sufficient financial and industrial resources were channelled into the building of aircraft, the results were likely to demonstrate that air power would grow in importance and become a key element in the war at sea.

While these high profile incidents helped to shape naval policy on both sides of the North Sea, the Germans wasted no time in beginning mining operations both in what could be termed their home waters – where the establishment of an integrated system of contact mine barrages known as the ‘Westwall’ was devised to protect their major naval bases – and in British coastal waters and particularly outside harbour entrances on the east coast where the intention was to cause as much damage and disruption to sea traffic as possible. For their part the British put most of their own effort into mining the Strait of Dover in order to make it a no-go area for U-boats much as it had been when Sir Roger Keyes had introduced a split level mine barrage in these same waters in 1917