Nummer: 27812
| Area : | Pacific Ocean |
| Sea area : | |
| Date of attack : | 24.12.1941 |
| Nationality of U-boat : | Japanese |
| U-boat : | I-21 |
| Commander : | Matsumura |
| presumed target type : | Tanker |
| presumed result : | sunk |
| Used weapon(s) : | Torpedo(es) |
| Date of observation : | 23.12.1941 |
| Time of observation : | 05:45 |
| Nationality of target : | American |
| Actual type of target : | Steam Tanker |
| Name of target : | Montebello |
| Year of launch : | 1921 |
| Actual tonnage : | 8272 BRT |
| Actual result : | sunk |
| Position of target : | 35.35n 121.16w |