Nummer: 00722
| Area : | Western Area |
| Sea area : | North Sea |
| Date of attack : | 06.12.1939 |
| Time of attack : | 07:54 |
| Nationality of U-boat : | German |
| U-boat : | U 31 |
| Commander : | Habekost |
| Grid : | AN 5341 |
| presumed target type : | Steam Freighter |
| presumed tonnage : | 2000 BRT |
| presumed result : | sunk |
| Number of torpedoes/mines : | 1 |
| Used weapon(s) : | Torpedo(es) |
| Date of last departure : | 05.12.1939 |
| Nationality of target : | Estonian |
| Actual type of target : | Steam Freighter |
| Name of target : | Agu |
| Year of launch : | 1885 |
| Actual tonnage : | 1575 BRT |
| Actual result : | sunk |
| Position of target : | Tyne - Gothenburg |
| Footnote : | The attack by U-31 could not have accounted for "Föina", which did not leave port until Dec.7th. Additionally "Föina" was en route Sarpsborg, Norway to Grangemouth (Firth of Forth). See FN.158 |
| updated on: | 00.00.0000 |
| Remark: | Föina (Anm.4) |
| Changes: | 1) Zimmermann, 9.1996 2) Kolbicz Liste 2002: Föina (Anm.4) |