Nummer: 17204a
| Area : | Western Area |
| Sea area : | Central Atlantic |
| Date of attack : | 21.09.1943 |
| Time of attack : | 20:01 |
| Nationality of U-boat : | German |
| U-boat : | U 123 |
| Commander : | Schroeter |
| Grid : | EP 4488 |
| presumed target type : | Tanker |
| presumed result : | damaged |
| Used weapon(s) : | Torpedo(es) |
| Convoy : | unknown |
| Footnote : | U-123 heard two hits and three additional detonations on a tanker and one Liberty ship. |
| related attacks : | Angriff 1 |
| Convoy : | unknown |