These were supported by an Ocean escort of eight Home Fleet destroyers led by Onslow (Capt.JA McCoy commanding).
Following the Battle of the North Cape on 26 December, which resulted in the sinking of the German battleship Scharnhorst, the threat from German surface units was, for the time being, eliminated, and RA 55B dispensed with the usual distant cover by heavy units of the Home Fleet.
RA 55A was however threatened by a U-boat force of some thirteen boats in a patrol line, code-named Eisenbart, in the Norwegian Sea, which had operated against all the December convoys.
German air reconnaissance was unable to find RA 55B in the gloom of the polar night, and although several Eisenbart boats made contact, their attacks were ineffectual.
The eight ships of RA 55B arrived in Britain without loss, while all German attempts to attack the convoy had failed.