|Ordered||14 Oct 1941|
|Laid down||7 Dec 1942||Blohm & Voss, Hamburg (werk 197)|
|Launched||18 Aug 1943|
|Commissioned||23 Sep 1943||Oblt. Hans Lehmann|
|Successes||1 ship sunk, total tonnage 1,603 GRT|
1 warship sunk, total tonnage 105 tons
1 ship damaged, total tonnage 4,287 GRT
Surrendered on 9 May 1945 at Narvik, Norway (Waller & Niestlé, 2010).
Transferred to Loch Eriboll, Scotland, on 19 May and later to Loch Ryan for Operation Deadlight.
Operation Deadlight (post-war Allied operation, info)
The U-boats that were in the Narvik area at the end of the war were all moved to the Skjomenfjord upon Allied orders to avoid conflicts with the Norwegians on 12 May. On 15 May, a German convoy of five ships (the fleet tender Grille with the staff of FdU Norwegen aboard, the fleet oiler Kärnten, the repair ship Kamerun and the depot ships Huascaran and Stella Polaris) and 15 U-boats (U-278, U-294, U-295, U-312, U-313, U-318, U-363, U-427, U-481, U-668, U-716, U-968, U-992, U-997 and U-1165) left for transfer to Trondheim, but was intercepted after two days by the 9th Escort Group off the Norwegian coast and officially capitulated. While the ships were allowed to proceed to Trondheim, the U-boats were escorted to Loch Eriboll, Scotland, arriving on 19 May. All U-boats were later that month transferred to Lisahally or Loch Ryan for Operation Deadlight.
U-997 operated with the following Wolfpacks during its career:
Grimm (31 May 1944 - 6 Jun 1944)
Trutz (17 Aug 1944 - 1 Sep 1944)
Grimm (13 Sep 1944 - 1 Oct 1944)
Regenschirm (14 Oct 1944 - 16 Oct 1944)
Panther (16 Oct 1944 - 8 Nov 1944)
Stier (21 Nov 1944 - 25 Dec 1944)
Hagen (15 Mar 1945 - 21 Mar 1945)
Attacks on this boat
5 Nov 1944
U-997 was attacked by an escort and sustained so much damage that she was forced to return to base.
1 recorded attack on this boat.
General notes on this boat
21 Apr 1945. On 21 April, 1945, in the Arctic Sea, an Allied U-boat hunter group attacked U-997 with depth charges. Due to some damage to the periscope, the boat had to return to base.
Men lost from the boat
24 Feb 1945
The boat lost a man overboard in the Arctic Sea. [Bootsmaat Erich Sachse]
Related: For more info on such losses see - Men lost from U-boats -