Nummer: 04211b
| Area : | Western Area |
| Sea area : | North Atlantic |
| Date of attack : | 09.02.1941 |
| Time of attack : | 04:30 |
| Nationality of U-boat : | German |
| U-boat : | U 37 |
| Commander : | Clausen |
| Grid : | CG 7555 |
| presumed target type : | Steam Freighter |
| presumed tonnage : | 4500 BRT |
| presumed result : | sunk |
| Number of torpedoes/mines : | - |
| Used weapon(s) : | Torpedo(es) |
| Convoy : | HG.53 |
| Date of observation : | 09.02.1941 |
| Time of observation : | 04:35 |
| Nationality of target : | British |
| Actual type of target : | Steam Freighter |
| Name of target : | Estrellano |
| Year of launch : | 1920 |
| Actual tonnage : | 1983 BRT |
| Actual result : | sunk |
| Position of target : | 35.53n 13.13w |
| related attacks : | Angriff 1 |
| Convoy : | HG.53 |
| Route of convoy : | Gibraltar - United Kingdom (home) |
| Remark to convoy : | Sep 1939 to Sep 1942, then MKF und MKS |