Nummer: 13710c
| Area : | Western Area |
| Sea area : | North Atlantic |
| Date of attack : | 18.11.1942 |
| Time of attack : | 04:13 |
| Nationality of U-boat : | German |
| U-boat : | U 521 |
| Commander : | Bargsten |
| Grid : | AK 4858 |
| presumed target type : | Steam Freighter |
| presumed tonnage : | 5000 BRT |
| presumed result : | damaged |
| Used weapon(s) : | Torpedo(es) |
| Convoy : | ONS.144 |
| Footnote : | U-521 heard two detonations after 8:10 min, another after after 12:02 min, and one more after 9:50 min. |
| related attacks : | Angriff 1 Angriff 2 |
| Convoy : | ONS.144 |
| Route of convoy : | United Kingdom - North America |
| Remark to convoy : | 1st series: Jul 1941 to Mar 1943 ON and ONS combined, later ON mit continuing and ONS with new numbering (counter traffic HX and SC) |