Nummer: 20812b
| Area : | Arctic Ocean |
| Sea area : | North Norway |
| Date of attack : | 24.08.1944 |
| Time of attack : | 01:53 |
| Nationality of U-boat : | German |
| U-boat : | U 997 |
| Commander : | Lehmann |
| Grid : | AC 5499 |
| presumed target type : | Destroyer |
| presumed result : | sunk |
| Number of torpedoes/mines : | 1 |
| Used weapon(s) : | Acoustic homing torpedo (gnat) |
| Convoy : | JW.59 |
| Actual tonnage : | ---- -- |
| Actual result : | hit not ascertained |
| Footnote : | U-997 heard two gnat (end-of-run) detonations after 7:00 min and 9:00 min. U-668 attacking at the same time heard gnat detonations after 1:35 min and 3:25 min. |
| related attacks : |
| Convoy : | JW.59 |
| Route of convoy : | Loch Ewe - (Iceland) - Kola Fjord - (Arkhangelsk) |
| Remark to convoy : | Since Dec 1942, former PQ (counter traffic = RA) |