Nummer: 02910b
| Area : | Western Area |
| Sea area : | North Atlantic |
| Date of attack : | 20.09.1940 |
| Time of attack : | 21:23 |
| Nationality of U-boat : | German |
| U-boat : | U 138 |
| Commander : | Lüth |
| Grid : | AM 5365 |
| presumed target type : | Steam Freighter |
| presumed tonnage : | 6500 BRT |
| presumed result : | sunk |
| Number of torpedoes/mines : | 1 |
| Used weapon(s) : | Torpedo(es) |
| Convoy : | OB.216 |
| Date of observation : | 20.09.1940 |
| Time of observation : | 20:24 |
| Nationality of target : | Panamanian |
| Actual type of target : | Steam Freighter |
| Name of target : | Boka |
| Year of launch : | 1920 |
| Actual tonnage : | 5560 BRT |
| Actual result : | sunk |
| Position of target : | 55.54n 07.24w |
| related attacks : | Angriff 1 Angriff 2 |
| Convoy : | OB.216 |
| Route of convoy : | Liverpool - North America (out) |
| Remark to convoy : | Sep 1939 to Jul 1940 via South Ireland, Jul to Okt 1940 via North Cannel, then ON. |