'Halfback (ii) was the British naval undertaking to facilitate the passage of the JW.64 convoy from Loch Ewe to the northern USSR (3/13 February 1945).

The close escort for this convoy of 26 laden ships as it departed Scottish waters comprised the destroyer Whitehall, the sloops Cygnet and Lark, and the corvettes Alnwick Castle, Bamborough Castle, Bluebell and Rhododendron, but this limited strength was boosted at sea by the arrival of Rear Admiral R. R. McGrigor’s force comprising the escort carriers Campania and Nairana, the light anti-aircraft cruiser Bellona, the destroyers Onslaught, Onslow, Opportune, Orwell, Serapis, Zambesi, Zealous, Zebra (forced to divert to the Færoe islands group), Zest and Canadian Sioux, the sloop Lapwing, the corvette Denbigh Castle, and the Free Norwegian armed whalecatcher Oksøy.

The two carriers' Fairey Swordfish warplanes were flown off to sweep the Leads off Vågsøy in an effort to spot and sink any German warships or U-boats that might interfere with JW.64’s passage a few days later. In the event the warplanes found little, and sank only one fishing vessel. At this time the Germans had decided to transfer three large destroyers from Narvik to the Baltic Sea from 26 January, and Admiral Sir Henry Moore, commanding the Home Fleet, learned of this movement on the following day, just after the escort carriers Campania and Nairana had departed for a sweep of the Leads near Vågsøy.

Moore believed that the German destroyers would probably follow the route inside the coastal islands, which was a practice much favoured by the Germans, and in that case it would be better for the warplanes of Air Vice Marshal S. P. Simpson’s No. 18 Group of Air Chief Marshal Sir William Sholto Douglas’s RAF Coastal Command to attack them by day than for warships to attempt interception in waters which were heavily mined and covered by numerous shore batteries. On the other hand, Moore had to take into consideration the fact that the Germans might have recourse to a high-speed night passage outside the Leads, although in that event it was doubtful that there was time for warships to be sortied from Scapa Flow to catch them. The Admiralty agreed that the inshore route was the more probable, but in case the Germans did in fact employ the offshore route Moore ordered Vice Admiral F. H. G. Dalrymple-Hamilton, with the light cruiser Mauritius and light anti-aircraft cruiser Diadem, to close the Norwegian coast in the area of Bergen, and then to sweep to the north in 'Halfback' (i).

Moore had no destroyers to send, unless he cancelled the carrier operation already in progress, a move which Moore did not consider justifiable. The two cruisers sighted the German destroyers at long range in bright moonlight just after 24.00 on 27/28 January, and in a high-speed pursuit severely damaged the leader, Z 31, and slightly damaged Z 38. The Germans fired torpedo salvoes without result, and then abandoned the attempt to break through, turning back to the north under cover of smoke. Though the British cruisers pursued them until they came under the fire of shore batteries, the superior speed of the destroyers enabled them to escape.

The three warships entered Bergen early on 28 January, and Z 31 went into dock. Z 33 and Z 38 sailed again the same evening, were attacked unsuccessfully by British warplanes on 29 January, and took shelter for the day in a fjord to the south of Stavanger. From here the two German warships finally reached Kiel safely on 1 February.

On the British side no one was satisfied with the inconclusive results of the encounter; but the truth was that the excellent visibility gave the Germans plenty of time to take evasive action, and it was hardly possible for large cruisers to force a conclusion with a faster opponent in the confined waters off the Norwegian coast.

On 6 February the JW.64 convoy was located by a German aeroplane on a meteorological reconnaissance sortie and reported, and a Junkers Ju 88 bomber was shot down by two Grumman Wildcat fighters from the escort carriers.

The 'Erasmus' U-boat pack, comprising U-286, U-307, U-425, U-636, U-711, U-716, U-739 and U-968, was deployed into the Bjørnøya Passage, and U-293, U-318, U-992 and U-995 to the area off the Kola inlet. On 7 February Oberstleutnant Georg Teske’s Kampfgeschwader 26 launched 48 Ju 88 bombers to attack the convoy, but missed the convoy and lost seven of its aircraft. On 8/9 February the Germans re-established temporary contact with the convoy by means of reconnaissance aircraft, and U-992 missed a destroyer on 8 February. On 10 February Major Rudolf Schmidt’s II/KG 26 and Major Wolf Harseim’s III/KG 26 launched another air attack, this time with 14 and 18 Ju 88 torpedo bombers respectively, but could find no way through the British fighters and anti-aircraft defences; five Ju 88 warplanes were shot down.

On 11 February the escort was strengthened with the arrival of the Soviet destroyers Trotsky, Karl Libknekht, Zhivuchiy and Zhestkiy, the patrol ship Grosz, two minesweepers and six submarine-chasers, and this Soviet escort took 12 transports and three tankers through to the White Sea.

The U-boats were unable to attack in face of an escort as strong as this, and were moved to the area off the Kola inlet. When the convoy entered the inlet on 13 February, Oberleutnant Hans Falke’s U-992 torpedoed the corvette Denbigh Castle, which was taken in tow by the Soviet salvage ship Bureaucratise, but ran aground, capsized and was written off as a total loss.

On 14 February Kapitänleutnant Hans-Günther Lange’s U-711 torpedoed the 7,200-ton US Horace Gray, which sank under tow from two Soviet tugs, and Oberleutnant Otto Westphalen’s U-968 torpedoed the 8,129-ton Norwegian tanker Norfolk, which ran aground and, perhaps hit by another torpedo from U-992, became a total loss.

U-995 had meanwhile missed the Norwegian steamship Ideogram in the harbour at Kirkenes on 9 February.