| Navy | The US Navy |
| Type | Minesweeper |
| Class | Auk |
| Pennant | AM 105 |
| Built by | Pennsylvania Shipyards Inc. (Beaumont, Texas, U.S.A.) |
| Ordered | |
| Laid down | 30 Oct, 1941 |
| Launched | 26 Jul, 1942 |
| Commissioned | 27 Feb, 1943 |
| End service | 8 Jul, 1946 |
| Loss position | |
| History | Decommissioned 8 July 1946 at San Diego, California Struck from the Naval Register 1 July 1972 Sold to Mexico 19 September 1972 and renamed Leandro Valle (C 70) |
| Noteable events involving Pioneer include: 26 Nov, 1943 |