Recent from talks
Convoy PQ 18
Knowledge base stats:
Talk channels stats:
Members stats:
Convoy PQ 18
Convoy PQ 18 (2–21 September 1942) was an Arctic convoy of forty Allied freighters from Scotland and Iceland to Arkhangelsk in the Soviet Union during the Second World War. The convoy departed Loch Ewe, Scotland on 2 September 1942, rendezvoused with more ships and escorts at Iceland and arrived at Arkhangelsk on 21 September. An exceptionally large number of escorts were provided by the Royal Navy in Operation EV, including the first escort carrier to accompany an Arctic convoy. Detailed information on German intentions was provided by the code breakers at Bletchley Park and elsewhere, through Ultra signals decrypts and eavesdropping on Luftwaffe wireless communications.
The German B-Dienst code-breakers read some British signals and the Luftwaffe used the lull in convoys after Convoy PQ 17 (27 June – 10 July) to prepare a maximum effort with the Kriegsmarine. From 12 to 21 September Convoy PQ 18 was attacked by bombers, torpedo-bombers, U-boats and mines, which sank thirteen ships at a cost of forty-four aircraft and four U-boats. The convoy was defended by escort ships and the aircraft of the escort carrier HMS Avenger which used signals intelligence gleaned from Ultra and Luftwaffe wireless frequencies to provide early warning of some air attacks and to attempt evasive routeing of the convoy around concentrations of U-boats. United States Navy Armed Guard and British Naval and Royal Artillery Maritime Regiment gunners were embarked on the freighters to operate anti-aircraft guns and barrage balloons, which made air attacks more difficult and because of inexperience, occasionally wounded men and damaged ships and cargo, with wild shooting.
The convoy handed over its distant escorts and Avenger to the homeward bound Convoy QP 14 near Archangelsk on 16 September and continued with the close escort and local escorts, riding out a storm in the Northern Dvina estuary and the last attacks by the Luftwaffe, before reaching Archangelsk on 21 September. Several ships ran aground in the storm but all were eventually refloated; unloading the convoy took a month. Because of its losses and the transfer in November of its most effective remaining aircraft to the Mediterranean, to oppose Operation Torch, the Luftwaffe effort could never be repeated.
In October 1941, after Operation Barbarossa, the German invasion of the USSR, which had begun on 22 June, 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 1,200 tanks a month from July 1942 to January 1943, followed by 2,000 tanks and another 3,600 aircraft more than already promised. 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 Hvalfjordur, Iceland, convenient for ships from both sides of the Atlantic. 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 who directed the speed, course and zig-zagging of the merchant ships and liaised 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 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 HMS Avenger (Commander Anthony Colthurst) had arrived from the United States and was added to the escort force, to give the convoy air cover.
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 (Heimish) 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 Heimish (Hydra from 1942, Dolphin to the British). By mid-1941, British Y-stations were able to receive and read Luftwaffe W/T transmissions and give advance warning of Luftwaffe operations.
In 1941, naval Headache personnel, with receivers to eavesdrop on Luftwaffe 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 Luftwaffe W/T signals intercepted by the Headaches. The Admiralty sent details of Luftwaffe wireless frequencies, call signs and the daily local codes to the computors, which combined with their knowledge of Luftwaffe procedures, could glean fairly accurate details of German reconnaissance sorties. Sometimes computors predicted attacks twenty minutes before they were detected by radar.
The rival German Beobachtungsdienst (B-Dienst, Observation Service) of the Kriegsmarine Marinenachrichtendienst (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, B-Dienst 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. B-Dienst 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. In early September, Finnish Radio Intelligence deciphered a Soviet Air Force transmission which divulged the convoy itinerary and forwarded it to the Germans.
Hub AI
Convoy PQ 18 AI simulator
(@Convoy PQ 18_simulator)
Convoy PQ 18
Convoy PQ 18 (2–21 September 1942) was an Arctic convoy of forty Allied freighters from Scotland and Iceland to Arkhangelsk in the Soviet Union during the Second World War. The convoy departed Loch Ewe, Scotland on 2 September 1942, rendezvoused with more ships and escorts at Iceland and arrived at Arkhangelsk on 21 September. An exceptionally large number of escorts were provided by the Royal Navy in Operation EV, including the first escort carrier to accompany an Arctic convoy. Detailed information on German intentions was provided by the code breakers at Bletchley Park and elsewhere, through Ultra signals decrypts and eavesdropping on Luftwaffe wireless communications.
The German B-Dienst code-breakers read some British signals and the Luftwaffe used the lull in convoys after Convoy PQ 17 (27 June – 10 July) to prepare a maximum effort with the Kriegsmarine. From 12 to 21 September Convoy PQ 18 was attacked by bombers, torpedo-bombers, U-boats and mines, which sank thirteen ships at a cost of forty-four aircraft and four U-boats. The convoy was defended by escort ships and the aircraft of the escort carrier HMS Avenger which used signals intelligence gleaned from Ultra and Luftwaffe wireless frequencies to provide early warning of some air attacks and to attempt evasive routeing of the convoy around concentrations of U-boats. United States Navy Armed Guard and British Naval and Royal Artillery Maritime Regiment gunners were embarked on the freighters to operate anti-aircraft guns and barrage balloons, which made air attacks more difficult and because of inexperience, occasionally wounded men and damaged ships and cargo, with wild shooting.
The convoy handed over its distant escorts and Avenger to the homeward bound Convoy QP 14 near Archangelsk on 16 September and continued with the close escort and local escorts, riding out a storm in the Northern Dvina estuary and the last attacks by the Luftwaffe, before reaching Archangelsk on 21 September. Several ships ran aground in the storm but all were eventually refloated; unloading the convoy took a month. Because of its losses and the transfer in November of its most effective remaining aircraft to the Mediterranean, to oppose Operation Torch, the Luftwaffe effort could never be repeated.
In October 1941, after Operation Barbarossa, the German invasion of the USSR, which had begun on 22 June, 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 1,200 tanks a month from July 1942 to January 1943, followed by 2,000 tanks and another 3,600 aircraft more than already promised. 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 Hvalfjordur, Iceland, convenient for ships from both sides of the Atlantic. 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 who directed the speed, course and zig-zagging of the merchant ships and liaised 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 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 HMS Avenger (Commander Anthony Colthurst) had arrived from the United States and was added to the escort force, to give the convoy air cover.
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 (Heimish) 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 Heimish (Hydra from 1942, Dolphin to the British). By mid-1941, British Y-stations were able to receive and read Luftwaffe W/T transmissions and give advance warning of Luftwaffe operations.
In 1941, naval Headache personnel, with receivers to eavesdrop on Luftwaffe 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 Luftwaffe W/T signals intercepted by the Headaches. The Admiralty sent details of Luftwaffe wireless frequencies, call signs and the daily local codes to the computors, which combined with their knowledge of Luftwaffe procedures, could glean fairly accurate details of German reconnaissance sorties. Sometimes computors predicted attacks twenty minutes before they were detected by radar.
The rival German Beobachtungsdienst (B-Dienst, Observation Service) of the Kriegsmarine Marinenachrichtendienst (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, B-Dienst 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. B-Dienst 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. In early September, Finnish Radio Intelligence deciphered a Soviet Air Force transmission which divulged the convoy itinerary and forwarded it to the Germans.
Recent media