Soviet reaction to the failure of their operation against the Faroes was not long in coming. They had already observed by satellite, and confirmed by air reconnaissance, the approach of the First Support Group and the Norwegian reinforcement convoy. On D + 5, therefore, twenty
Rather more one-sided was the Soviet attack on the North Sea oil and gas installations. Appreciating that the most vulnerable, and least easily defended, elements in the supply from wells to shore were the pipelines on the sea-bed, the Russians had decided to cut these. It was not difficult to do this, except in the southern North Sea, which initially was not readily accessible to the attackers. In the north, six diesel-electric submarines, approaching via the deep water off the Norwegian coast, were deployed to predetermined positions, where they released special underwater manned vehicles, to locate and destroy the twelve most important pipelines. By using delayed action charges, the submarines were able to withdraw without detection.
Three of them, operating in the shallower areas, also laid mines in the vicinity of the pipelines, where the destruction would occur. Two NATO patrol ships, sent to investigate the explosions on 8 August, struck mines and sank. In order to distract attention from the submarine operations, sporadic air attacks, using stand-off missiles, were carried out on some of the oil and gas rigs themselves. The UK air defences took a heavy toll of the elderly
The final major event of the war at sea, during the opening phase of the Warsaw Pact onslaught, was the declaration by the Soviet government on 9 August that the Western Approaches was a War Zone, into which shipping of any kind entered at its peril. The only neutral countries within the War Zone were Sweden and Finland. The Swedes were told that the inconvenience they would suffer would not last long and that the action had been forced upon the Warsaw Pact by the aggressive intentions of NATO. The Soviet objective of neutralizing the Federal German Republic would soon be achieved. The correlation of forces made this inevitable. As to Finland, it was hardly necessary to seek her compliance.
The declaration of the War Zone was not regarded by the Soviet Union as sufficiently emphatic of itself. Certain of her submarines, which had been ordered to take up patrol positions and at all costs to remain undetected, were therefore ordered to attack with tactical missiles, after careful identification, certain important ships — oil tankers, container ships and dry cargo ships belonging to European NATO countries. Sailing weeks earlier from distant ports, along standard ocean routes, these ships had been ordered to continue at full speed, some towards the North Channel and some towards St George’s Channel, where they would be met and escorted into harbour. Ships which were more than five days’ steaming from Western Approaches coastal waters had been turned towards the nearest NATO friendly or neutral port or anchorage, to await further instructions.
Late on 9 August reports reached JACWA that two large oil tankers, two container ships and two dry cargo ships had been attacked without warning with submarine-launched missiles. The positions given, four in the Bay of Biscay and two west of Ireland, could not immediately be reconciled with the plotted positions of any Soviet submarines, as deduced from the various anti-submarine detection or surveillance systems. If ever the gravity of the Soviet submarine threat to shipping had been doubted, such doubts were now speedily removed. Against nuclear-powered submarines, aided by satellite and aircraft reconnaissance, even the fastest merchant ships were sitting ducks.