JW51B: the big picture

It is December 1942 and the Allies are striving to get merchant convoy JW51B to Murmansk with valuable supplies for the Russians.

British details are here: sheriff
German details are here: obelisk
Stacks Image 343

Preliminary plans

Rear Admiral Choke is commanding the Royal Navy assets in the area. His forces consist of:

Air cover - from the carrier Victorious, limited to the region around Bear Island
17th DD Flotilla - consisting of the destroyers Cameron, Churchill, Newport, Comet, Caesar, and Cossack.

Force 12 - cruisiers Belfast and Ajax and the destroyers Encounter and Whirlwind
Distant cover - battleship Prince of Wales, cruiser Devonshire, destroyers Ashanti, Javelin, and Jackal. This is limited to the area to the W of the red line on the map.
Submarines Graph and Seadog.

Choke's plan (see below) is for convoy JW51B, with 17 DD flotilla escorting, to travel to Murmansk along a route approximately halfway between the edge of the ice pack and the northern coast of Norway.

Distant Cover shadows the convoy to its south.

The two submarines patrol just beyond the reach of German aircraft, moving back and forth to try and intercept any forces leaving Alten Fjord.

Force 12 makes best speed from Murmansk, meeting the convoy at "Neptune", before escorting it to Murmansk.

After Force 12 begins escorting JW51B, Distant Cover moves south to support the two submarines.
Stacks Image 344
The German commander is Admiral zur See Klaus von Steinfinkel, operating from the battleship Graf Spee. His forces are:

Force A - cruiser Admiral Hipper, destroyers Leberecht Maas and Max Shultz
Force B - battleship Graf Spee (flagship), destroyers Richard Beitzen and Paul Jacobi
Force C - cruiser Koln and destroyers Wolfgang Zenker and Hans Lody
U-boot - U255, U345, U586, U625

The submarines are at sea, with all other forces at Alten Fjord.
Steinfinkel's submarines form a line across the route of the convoy. The other forces are to leave Alten Fjord in sequence, reinforcing the line. The line will then slowly sweep to the west, searching for the convoy.
Stacks Image 345

30 Dec 1942 1200 - "SIGNIFICANT NAVAL ACTIVITY"

Stacks Image 346

30 Dec 1942 2330 - "CONTACT!"

The three German surface groups sailed north, 20 nm apart, directly towards the patrol area of HMS Seadog. Luckily for them Seadog's patrolling took it back and forth between the groups of ships and they were not even detected.

The German forces were just reaching their positions for their synchronised turn to the west when Force 12 approached the German Force A from the SW.

Both groups detected each other, despite the Force 10 gale in the area, reporting to their commanders.

Admiral Choke immediately ordered Force 12 to investigate the contacts, and his own Distant Cover force to intercept. He ordered JW51B to divert 50 nm to the north to avoid the threat. He also requested that HMS Victorious be released from the Bear Island region to support him, but the request was denied.
Admiral Steinfinkel was slower responding. His ships only received their new orders after they had begun their slow westward sweep.

He incorrectly assumed that the contacts were the convoy itself and ordered Force A to engage the contacts and the rest of his forces (other than U256) to converge on a point to the E, where he anticipated "the convoy" being at the time of intercept.

Both the German Force A and the British Force 12 attempted to engage each other, without success because of the foul weather conditions in the area rendering movement (especially by the destroyers) almost impossible.
Stacks Image 347

31 Dec 1942 0000 - The weather improves...

Stacks Image 348
The storm drops from Force 10 down to Force 7, allowing the German Force A and British Force 12 to engage.

Combat is between:

German Force A: Admiral Hipper, Leberecht Maas, Max Shultz

British Force 12: Force 12 (Captain Robert Likely) Belfast CL, Ajax CL, Encounter DD, Whirlwind DD

Weather: Force 7, visibility 10,000 yards (50 cm), no squalls,

Speed changes:
  • BA-CS (-5 kt, up 1 row on gunnery),
  • DD (25 kt max, up 2 row on gunnery). Sensor +3 to ADR.
Forces are separated by 80 cm (16,000 yards) .
Three German blips, two British blips.
Force 7 winds, no RDF.
Forces aligned N to S.

Battle is detailed here: X17A
Battle completed 00:36.

31 Dec 1942 0200 - Some near misses

Force 8 winds
U625 and Seadog miss each other in the bad weather (BB16-CC16).
U586 misses Force 12 too (Y15, X16)

31 Dec 1942 0300 - Some near misses

Force 7 winds
Progress game. No contacts. Request further orders from both sides.

31 Dec 1942 0400 - A report

Force 7 winds
Possible contact
British Distant Cover X18
German U586 W19
U586 detects but cannot attack.
Reports back to German HQ, who order all forces to move to X21.

31 Dec 1942 0500

Force 8 winds
Possible contact
German U255 S20
British Force 12 T20 (Belfast, Ajax, Encounter)
Neither side spots

31 Dec 1942 0600

Force 7 winds
Possible contact
German U625 X21
British Distant Cover Y20
Submarine no contact.


Weather

30/12/42


1200 04 Force 04 ****
1300 08 Force 07 *******
1400 04 Force 04 ****
1500 02 Force 03 ***
1600 03 Force 04 ****
1700 04 Force 04 ****
1800 05 Force 05 *****
1900 07 Force 07 *******
2000 09 Force 07 *******
2100 06 Force 05 *****
2200 07 Force 07 *******
2300 12 Force 10 **********

01/01/43


0000 08 Force 07 *******
0100 10 Force 08 ********
0200 06 Force 05 *****
0300 08 Force 07 *******
0400 09 Force 07 *******
0500 10 Force 08 ********
0600 08 Force 07 *******
0700 06 Force 05 *****
0800 08 Force 07 *******
0900 09 Force 07 *******
1000 10 Force 08 ********
1100 08 Force 07 *******
1200 06 Force 05 *****
1300 06 Force 05 *****
1400 04 Force 04 ****
1500 08 Force 07 *******
1600 06 Force 05 *****
1700 04 Force 04 ****
1800 02 Force 04 ***
1900 06 Force 05 *****
2000 06 Force 05 *****
2100 06 Force 05 *****
2200 06 Force 05 *****
2300 06 Force 05 *****