Nummer: 27018a
| Area : | Indic Ocean |
| Date of attack : | 10.09.1943 |
| Nationality of U-boat : | Japanese |
| U-boat : | I-27 |
| Commander : | Fukumura |
| presumed target type : | Steam Freighter |
| presumed result : | sunk |
| Used weapon(s) : | Torpedo(es) |
| Date of observation : | 09.09.1943 |
| Time of observation : | 17:00 |
| Nationality of target : | British |
| Actual type of target : | Motor Freighter |
| Name of target : | Larchbank |
| Year of launch : | 1925 |
| Actual tonnage : | 5151 BRT |
| Actual result : | sunk |
| Position of target : | 07.38n 74.00e |
| Footnote : | With "Larchbank" the MTB-284 and MTB-285 were lost. |
| related attacks : | Angriff 1 Angriff 2 |