Luftflotte 5 (Air Fleet 5), the Luftwaffe force in Norway, was reinforced with bombers and torpedo-bombers in early 1942 and reorganised to attack convoys as they passed between the Norwegian coast and the ice of the Arctic, which was still close to its southern winter limit.

The sun remained above the horizon at this time of year and the deck crews of the ships found the perpetual daylight fatiguing and stressful; glare from sunshine reflecting off ice being particularly difficult for observers.

The USSR turned out to lack the ships and escorts and the British and Americans, who had made a commitment to "help with the delivery", undertook to deliver the supplies for want of an alternative.

The main Soviet need in 1941 was military equipment to replace losses because, at the time of the negotiations, two large aircraft factories were being moved east from Leningrad and two more from Ukraine.

In winter, polar ice can form as far south as 50 mi (80 km) of the North Cape and in summer it can recede to Svalbard, forcing ships closer to Luftwaffe air bases or being able to sail further out to sea.

[9] Despite the views of the Navy, Churchill came under pressure from the president of the United States, Franklin D. Roosevelt and the Soviet leader, Joseph Stalin, bowed to political reality and ordered the dispatch of a larger convoy to reduce the backlog, The operation is justified if half gets through.

Failure on our part to make the attempt would weaken our influence with both our major allies.The British Government Code and Cypher School (GC&CS) based at Bletchley Park housed a small industry of code-breakers and traffic analysts.

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.

Fliegerführer Nord (West) was based at Sola and was responsible for the early detection of convoys and attacks south of a line from Trondheim westwards to Shetland and Iceland, with 1./(F) 22, the Kondors of 1./KG 40, short-range coastal reconnaissance squadrons 1./Küstenfliegergruppe 406 (1./Kü.Fl.Gr.

[17] As soon as information was received about the assembly of a convoy, Fliegerführer Nord (West) would send long-range reconnaissance aircraft to search Iceland and northern Scotland.

In April, the spring thaw grounded many Luftwaffe aircraft and in May bad weather led to contact being lost and convoys scattering, being impossible to find in the long Arctic night.

[24] The convoy formed nine columns with a close escort of the minesweeper HMS Hazard and the naval trawlers St Elstan, Lady Madeleine, Northern Spray and the Free French Retriever, which had to return after three days, being too slow to keep up.

The convoy sailed eastwards in a moderate sea breeze but the endless daylight continued to affect the crews above decks, making them more tense and fatigued.

[29] A BV 138 took over the shadowing from the Kondor and the first air attack began at 7:10 p.m. Several Ju 88s and 9 Heinkel 111 torpedo-bombers from 3./KG 26 (Hauptmann Eicke), six of which turned back due to the clear sky.

The convoy hugged the pack ice and by mid-morning was able to change course to the east but the diversion had brought PQ 16 closer to the German air bases in northern Norway.

With the cruiser covering force gone, only Alynbank and Martin could elevate their main armament for anti-aircraft action; the other destroyers and corvettes had to wait until aircraft were within range of their lighter guns.

[34] The crew of Alynbank counted 108 attacks during the day and near noon, Stary Bolshevik, carrying ammunition and vehicles, was hit forward by a bomb and set on fire.

A and B guns were knocked out along with an Oerlikon, some smoke floats were set alight and dumped overboard and the wireless aerials were brought down, requiring Lady Madeleine to sail alongside to relay messages from Ashanti.

The ship was strafed and dive-bombed as Honeysuckle rescued the survivors; Lowther Castle burned for another eight hours before exploding astern of the convoy in a big plume of smoke.

As Hyderabad had recovered survivors from Empress Purcell it had been ordered to transfer ammunition from John Randolph to Hybert and Pieter de Hoogh also requested replenishment.

Ocean Voice, carrying the convoy commodore, was hit by a bomb which blew a hole in the hull close to the waterline near the forward hold and caused a fire.

The flotilla was to escort the six ships bound for Archangelsk along with Martin and Alynbank, depriving PQ 16 of its best long-range radars, just as the convoy was about to enter an area patrolled by U-boats.

The detached section reached the estuary of the Northern Dvina and met the icebreaker Stalin off Sozonoya, spending the next forty hours following it in line astern, during which they were attacked by Ju 87 dive-bombers to no effect.

[20] In 2001 Adam Claasen wrote that the losses inflicted on PQ 16 amounted to half the number of ships sunk by the Luftwaffe during April and May, the reinforcement of Luftflotte 5 and the longer hours of daylight, putting Arctic convoys at an increasing disadvantage.

[45] In 2004, Richard Woodman wrote that PQ 16 had mainly had to defend itself from air attack and that in Onslow's judgement, despite the exemplary performance of Alynbank, most of the escorts were lacking in anti-aircraft firepower.

[47] Dönitz wrote in his war diary, My opinion as to the small chances of success for U-boats against convoys during the northern summer...has been confirmed by experience with PQ 16....This must be accounted a failure when compared with the results of the anti-submarine activity for the boats operating.

[48]Dönitz thought that the Luftwaffe would be more effective during the summer months, somewhat misled by the exaggerated claims of the bomber and torpedo-bomber pilots, despite the convoy being shadowed for much of the journey by reconnaissance aircraft.

[50] When at action stations many sailors had been seriously injured by explosions throwing them upwards into the deck above and Ransome Wallis followed the general order to lie down instead, until he realised, somewhat to his embarrassment, that no-one did this on Martin.

[51] Ransome Wallis took the SBA and two Neil Robertson stretchers; the Russian ship was 300 yd (270 m) away and as the whaler was rowed across more German aircraft appeared and Stary Bolshevik got under way.

Everyone in the whaler worked an oar as German bombs fell around, soaking the occupants, who rapidly caught up with the ship and tied onto a rope ladder on the port side.