Nummer: 05801a
| Area : | Western Area |
| Sea area : | North Atlantic |
| Date of attack : | 27.06.1941 |
| Time of attack : | 01:55 |
| Nationality of U-boat : | German |
| U-boat : | U 564 |
| Commander : | Suhren |
| Grid : | AK 2432 |
| presumed target type : | Steam Freighter |
| presumed tonnage : | 8000 BRT |
| presumed result : | sunk |
| Number of torpedoes/mines : | 3- |
| Used weapon(s) : | Torpedo(es) |
| Convoy : | HX.133 |
| Date of observation : | 26.06.1941 |
| Time of observation : | 23:53 |
| Nationality of target : | Dutch |
| Actual type of target : | Steam Freighter |
| Name of target : | Maasdam |
| Year of launch : | 1921 |
| Actual tonnage : | 8812 BRT |
| Actual result : | sunk |
| Position of target : | 60n 30.35w |
| related attacks : | Angriff 1 Angriff 2 |
| Convoy : | HX.133 |
| Route of convoy : | (New York) - Halifax - United Kingdom |
| Remark to convoy : | Sep 1939 to Sep 1942 ab Halifax, then from New York (counter traffic = ON), vgl. HXF und SC. |