Arctic convoys The Soviet authorities had claimed that the unloading capacity of Arkhangelsk was , Vladivostok and by the
Persian Gulf route. When surveyed by British and US technicians, the capacity of the ten berths at Arkhangelsk was assessed as and the same from Murmansk from its eight berths. By late 1941, the convoy system used in the Atlantic had been established on the Arctic run; a
convoy commodore ensured that the ships' masters and signals officers attended a briefing before sailing to make arrangements for the management of the convoy, which sailed in a formation of long rows of short columns. The commodore was usually a retired naval officer, aboard a ship identified by a white pendant with a blue cross. The commodore was assisted by a Naval signals party of four men, who used lamps, semaphore flags and telescopes to pass signals, coded from books carried in a bag, weighted to be dumped overboard. In large convoys, the commodore was assisted by vice- and rear-commodores to direct the speed, course and zig-zagging of the merchant ships and liaise with the escort commander. Following
Convoy PQ 16 and the disaster to
Convoy PQ 17 in July 1942, Arctic convoys were postponed for nine weeks and much of the Home Fleet was detached to the Mediterranean for
Operation Pedestal, a
Malta convoy. During the lull, Admiral
John Tovey concluded that the Home Fleet had been of no great protection to convoys beyond Bear Island, midway between
Spitsbergen and the
North Cape. Tovey would oversee the operation from
Scapa Flow, where the fleet was linked to the Admiralty by landline, immune to variations in wireless reception. The next convoy should be accompanied by sufficient protection against surface attack; the longer-range destroyers of the Home Fleet could be used to augment the close escort force of anti-submarine and anti-aircraft ships, to confront a sortie by German ships with the threat of a massed destroyer torpedo attack. The practice of meeting homeward-bound QP convoys near Bear Island was dispensed with and Convoy QP 14 was to wait until Convoy PQ 18 was near its destination, despite the longer journey being more demanding of crews, fuel and equipment. The new
escort carrier (Commander Anthony Colthurst) had arrived from the United States and was added to the escort force.
First Protocol The Soviet leaders needed to replace the colossal losses of military equipment lost after the
German invasion, especially when Soviet war industries were being moved out of the war zone and emphasised tank and aircraft deliveries. Machine tools, steel and aluminium was needed to replace indigenous resources lost in the invasion. The pressure on the civilian sector of the economy needed to be limited by food deliveries. The Soviets wanted to concentrate the resources that remained on items that the Soviet war economy that had the greatest comparative advantage over the German economy. Aluminium imports allowed aircraft production to a far greater extent than would have been possible using local sources and tank production was emphasised at the expense of lorries and food supplies were squeezed by reliance on what could be obtained from lend–lease. At the Moscow Conference, it was acknowledged that 1.5 million tons of shipping was needed to transport the supplies of the First Protocol and that Soviet sources could provide less than 10 per cent of the carrying capacity. The British and Americans accepted that the onus was on them to find most of the shipping, despite their commitments in other theatres. The Prime Minister,
Winston Churchill, made a commitment to send a convoy to the Arctic ports of the USSR every ten days and to deliver a month from July 1942 to January 1943, followed by and another more than already promised. In November, the US president,
Franklin D. Roosevelt, ordered Admiral
Emory Land of the US Maritime Commission and then the head of the
War Shipping Administration that deliveries to Russia should only be limited by 'insurmountable difficulties'. The first convoy was due at Murmansk around 12 October and the next convoy was to depart Iceland on 22 October. A motley of British, Allied and neutral shipping loaded with military stores and raw materials for the Soviet war effort would be assembled at
Hvalfjörður in Iceland, convenient for ships from both sides of the Atlantic. From
Operation Dervish to
Convoy PQ 11, the supplies to the USSR were mostly British, in British ships defended by the Royal Navy. A fighter force that could defend Murmansk was delivered that protected the Arctic ports and railways into the hinterland. British supplied aircraft and tanks reinforced the Russian defences of Leningrad and Moscow from December 1941. The tanks and aircraft did not save Moscow but were important in the Soviet counter-offensive. The was by then reduced to 600 operational aircraft on the Eastern Front, to an extent a consequence of being sent to the Mediterranean against the British. Tanks and aircraft supplied by the British helped the Soviet counter-offensive force back the Germans further than might have been possible. In January and February 1941, deliveries of tanks and aircraft allowed the Russians to have a margin of safety should the Germans attempt to counter-attack. Post-war criticism of the quality of British supplies contradicted the praise offered to the
Foreign Secretary,
Anthony Eden, in Moscow in December, of the performance of
Hurricane fighters and
Valentine tanks;
Matilda tanks were admittedly inferior in snow but were expected to operate better in the summer. Deliveries helped to improve the long-term potential of the Soviet war economy, the of aluminium sent from Britain was the equivalent to the capacity lost in the Soviet Union in the six months from October 1941 and each of copper and rubber were generally useful to the Soviet economy, especially after rubber from Malaya was cut off by the
Malayan campaign (8 December 1941 – 15 February 1942).
Radar and
Asdic apparatuses improved Russian anti-aircraft defences and the naval protection of the Arctic ports. In the first winter of the war in Russia the British helped to tide the USSR over at some cost to British grand strategy; the 700 fighters and about 500 tanks sent to Russia in 1941 could have made a substantial difference to British fortunes in the
Middle East and
Far East. The Germans laid plans to stop the Arctic convoys in 1942.
Signals intelligence Bletchley Park The British
Government Code and Cypher School (GC&CS) based at
Bletchley Park housed a small industry of code-breakers and
traffic analysts. By June 1941, the German
Enigma machine Home Waters () settings used by surface ships and U-boats could quickly be read. On 1 February 1942, the Enigma machines used in U-boats in the Atlantic and Mediterranean were changed but German ships and the U-boats in Arctic waters continued with the older (
Hydra from 1942, Dolphin to the British). By mid-1941, British
Y-stations were able to receive and read
W/T transmissions and give advance warning of operations. In 1941, naval
Headache personnel, with receivers to eavesdrop on wireless transmissions, were embarked on warships and from May 1942, ships gained RAF Y
computor parties, which sailed with cruiser admirals in command of convoy escorts, to interpret W/T signals intercepted by the Headaches. The Admiralty sent details of wireless frequencies, call signs and the daily local codes to the computors, which combined with their knowledge of procedures, could glean fairly accurate details of German reconnaissance sorties. Sometimes computors predicted attacks twenty minutes before they were detected by radar.
B-Dienst The rival German (, Observation Service) of the (MND, Naval Intelligence Service) had broken several Admiralty codes and cyphers by 1939, which were used to help
Kriegsmarine ships elude British forces and provide opportunities for surprise attacks. From June to August 1940, six British submarines were sunk in the Skaggerak using information gleaned from British wireless signals. In 1941, read signals from the Commander in Chief Western Approaches informing convoys of areas patrolled by U-boats, enabling the submarines to move into "safe" zones. had broken Naval Cypher No 3 in February 1942 and by March was reading up to 80 per cent of the traffic, which continued until 15 December 1943. By coincidence, the British lost access to the
Shark cypher and had no information to send in Cypher No 3 which might compromise Ultra. ==Convoy organisation==