After the K-21 attack, the German ships continued on their original course for approximately five hours before turning back.
Notes on verification
Confirmed by Wikipedia's account of the Tirpitz K-21 attack and corroborated by an independent operational timeline (kbismarck.com), with consistent timing details.
Sources
- Attack on the battleship Tirpitz by submarine K-21 (en.wikipedia.org)
- https://www.kbismarck.com/tirpitz.html (kbismarck.com)
- https://www.worldnavalships.com/forums/thread.php?threadid=10818 (worldnavalships.com)
- https://uboat.net/allies/warships/ship/3559.html (uboat.net)
- https://www.globalsecurity.org/military/world/europe/history/kms-tirpitz.htm (globalsecurity.org)