To begin with Russia-bound convoys would consist of fifteen or so merchant ships, concentrated in north-west Scotland at Loch Ewe and/or Icelandic ports; however as the situation became more pressing, the number of ships increased to thirty or more. The escort would usually consist of a distant force of heavy ships from the Home Fleet comprising (dependent upon availability) a battleship or battlecruiser, one or more heavy cruisers and a destroyer screen. An aircraft carrier should ideally have accompanied the heavy ships or the convoy itself to give air cover, but this was rarely possible due to the lack of carriers available to the fleet until the specifically designed escort carriers began to come on stream in 1943. The capital ships from the Home Fleet would operate some 300–400 miles[10] (552–742 km) from the convoy, but remain within high-speed striking distance in the hope of catching German surface raiders operating from northern Norway. The British heavy ships would not, however, proceed east of Bear Island (see map A p. 144), as this would bring them within range of U-boats and the Luftwaffe. Secondly, there would be a detached covering force, usually two light cruisers, which would shadow the convoy through the Barents Sea, remaining at some 30–40 miles (55–75 km) distance, also to avoid U-boats. Close escort and anti-submarine protection would be provided by destroyers supported by an assorted force of corvettes, trawlers, minesweepers and occasionally, during summer months when the Luftwaffe was active, an anti-aircraft cruiser.
By 1942 Hitler was becoming convinced that the Allies planned an invasion of Norway, and to counter this threat and bolster attacks on the Arctic convoys he ordered a concentration of German capital ships in Norwegian waters. The battleship Tirpitz was subsequently located by British reconnaissance in Aas Fjord, 15 miles (27 km) from Trondheim, on 23 January 1942; while on 11 February the battlecruisers Scharnhorst and Gneisenau, accompanied by the heavy cruiser Prinz Eugen and escorts, began their epic dash from Brest northward through the English Channel. British forces were slow to react and the ships got through undamaged by air and sea attacks; however Gneisenau hit a mine and Scharnhorst hit two. Both ships were able to proceed to German ports, where Gneisenau was further damaged by air attack while in dry dock at Kiel. Prinz Eugen continued on to Norway in company with the pocket battleship Admiral Scheer, and although the heavy cruiser was torpedo-damaged en route, a powerful German naval force was now building up.
In the meantime a further four convoys, PQ8, 9, 10 and 11, had by the last week of February delivered cargo from fifty-six merchantmen into Murmansk (Archangel being frozen during the Arctic winter), for the loss of one ship sunk, and one damaged but towed to the Kola Inlet (the entrance to Murmansk).
German actions against the convoys inevitably grew in intensity, and losses of both merchant and naval vessels in the Arctic began to mount, to the extent that the Admiralty proposed that sailings be suspended for the summer months, the period of perpetual Arctic daylight. Churchill, pressed by both Stalin and Roosevelt to increase not decrease shipments, vetoed the proposal. His memo of 17 May 1942 to General Sir Hastings Ismay, Chief of Staff to the Minister of Defence and liaison with the Chiefs of Staff Committee, explains the predicament:
1. Not only Premier Stalin but President Roosevelt will object very much to our desisting from running the convoys now. The Russians are in heavy action, and will expect us to run the risks and pay the price entailed by our contribution. The United States ships are queuing up. My own feeling, mingled with much anxiety, is that the convoy ought to sail on the 18th [of May]. The operation is justified if a half get through. The failure on our part to make the attempt would weaken our influence with both our major allies. I share your misgivings but I feel it is a matter of duty.
2. I presume all the ships are armed with AA guns and that not more than 25 would be sent.
3. I will bring the question before the Cabinet tomorrow (Monday) in your presence, but meanwhile all preparations should proceed.[11]
The convoy in question, PQ16, consisting of thirty-five merchant ships, subsequently sailed on 21 May and on 27 May was subjected to attacks by 108 torpedo bombers. These attacks continued for five days, but losses were kept down to six ships. Churchill had in some measure trusted to luck and that luck had held; however it was about to run out.
On Finnish and Norwegian airfields around the North Cape, the northernmost tip of Norway, the Luftwaffe assembled a formidable force of torpedo bombers, dive bombers, level bombers and fighter support. In addition Admiral Doenitz, C-in-C of the U-boat arm of the Kriegsmarine, received orders to increase the number of operational units in the Arctic to ten.
As all available Allied escorts were required for Operation Harpoon, a convoy for the relief of hard-pressed Malta, the next Russia convoy, PQ17, was scheduled for the end of June.
The Admiralty in general, and C-in-C Home Fleet Admiral Tovey in particular, were very well aware that running convoys through to Arctic Russia in the summer months of perpetual daylight would incur substantial risk of heavy loss in merchant and escort vessels and their crews. The chances of discovery by U-boats or round-the-clock Luftwaffe reconnaissance would be virtually certain.
Up to this point the German high command had used only U-boats and air attack against convoys, but Admiral Tovey and Admiral of the Fleet Sir Dudley Pound were convinced that surface raiders would also be brought into action, including the battleship Tirpitz. The upper echelons of Naval High Command had a wary respect for this powerful adversary, fearing disaster should she ever get loose. In conversations between the two men Sir Dudley Pound advised Admiral Tovey that if Tirpitz were to break out of her Norwegian base to intercept a convoy, he might well order it to scatter. Tovey was not in agreement with this approach, believing that nothing would be gained as the merchantmen would then be isolated and picked off at will by U-boat and aircraft attack. Keeping the convoy together, he maintained, would at least give the close escort some chance of harassing and delaying the attackers until British capital ships could be brought into action in support.
Convoy PQ17 comprised thirty-five merchantmen, and sailed on 27 June 1942 from the Icelandic port of Hvalfjord. Covering the passage to Russia, a powerful escort included with the Home Fleet distant-covering force the aircraft carrier HMS Victorious, and for the first time ships of the US Navy accompanying both the Home Fleet units and the detached cruiser force in the Barents Sea.
Also very aware of the improved prospects for attacking Russia-bound convoys which summer provided, Grand Admiral Erich Raeder fully intended to combine operations by Tirpitz and the German battle group in Norway with attacks by U-boats and the Luftwaffe. However, he also had his problems, not least of which was Hitler’s extreme reluctance to put his heavy ships at risk. Hitler insisted that before convoys were attacked by major German surface units, any British aircraft carriers with the supporting forces were to be attacked and destroyed by the Luftwaffe. This placed an impossible handicap on the German naval high command, and was compounded by the Führer’s orders that no attacks were to be made by any German heavy ships unless he personally gave the order for them to sail.[12] In an attempt to comply with these crippling restrictions, Raeder devised Operation Rosselsprung (‘Knight’s Move’), which was to be carried out in two phases. Upon detection of a convoy the German heavy ships were to sail from their bases along the Norwegian coast to concentrate at sortie ports in northern Norway, there to await Hitler’s final sanction for an offensive operation. This movement in advance of final attack orders would have a completely unforeseen outcome.
10
a From this point on ‘miles’ will refer to nautical miles, with the appropriate metric conversion, unless otherwise stated.