Nummer: 13521b
| Area : | Western Area |
| Sea area : | West African Coast |
| Date of attack : | 11.11.1942 |
| Time of attack : | 19:55 |
| Nationality of U-boat : | German |
| U-boat : | U 173 |
| Commander : | Schweichel |
| Grid : | DJ 2519 |
| Used weapon(s) : | Torpedo(es) |
| Convoy : | UGF.1 |
| Date of observation : | 11.11.1942 |
| Time of observation : | 19:55 |
| Nationality of target : | American |
| Actual type of target : | Fleet Oiler |
| Name of target : | Winooski (AO.38) |
| Year of launch : | 1941 |
| Actual tonnage : | 10600 BRT |
| Actual result : | damaged |
| Position of target : | 33.45n 07.22w |
| Footnote : | U-173 heard three detonations and assumed one hit. No optical observations were made because of ASW operations. |
| related attacks : | Angriff 1 Angriff 2 |
Fleet Oiler Winooski (AO.38) ex American Calusa (bis 1941)
| Convoy : | UGF.1 |
| Route of convoy : | U.S.A. - Gibraltar (fast) |
| Remark to convoy : | Since Oct 1942, initially for Op. Torch, then to ports in Northwest-Africa |