Cossack's first action was on 16 February 1940, under the command of
Philip Vian. This was the
Altmark Incident in
Jøssingfjord,
Norway which resulted in the freeing of the
Admiral Graf Spee's prisoners who were being held aboard the supply ship
Altmark and the death of eight crew members of the German ship.
In the Incident the German tanker rammed her with the stern in an angle of about 30° at the altitude of her bridge and pressed the destroyer towards the fiord wall. The Norwegian officers present later reported, that only the mass of ice piled up averted the destroyer to crash onto the rocky shore. The powerful engines of the destroyer made her escape from the squeeze possible.
[3] Cossack arrived at
Leith on 17 February with the 299 freed prisoners.
[4] She had to be docked for her propellor and A-brackets to be checked in case they had been damaged by the thick ice in the fiord. They were unharmed, but her stern plating had to be repaired where it had been bumping against
Altmark.
[5]